Taxonomy of the Garlic (Allium sativum L.) according to Cronquist System
Superdominium/Superdomain: Biota
Dominium/SuperKingdom: Eucariota Whittaker & Margulis,1978
Regnum/Kingdom: Plantae Haeckel, 1866
Subregnum/Subkingdom : Viridaeplantae Cavalier-Smith, 1998 (Green Plants)
Superdivisio/Superdivision: Spermatophyta Gustav Hegi, 1906
Divisio/Division or Phylum: Tracheophyta Sinnott, 1935 ex Cavalier-Smith, 1998 -
Subdivisio/Subdivision: Magnoliophytina Frohne & U. Jensen ex Reveal, 1996
Classis/Class: Liliopsida Brongn., 1843
Subclassis/Subclass: Liliidae J.H. Schaffn.,1911
SuperOrdo/SuperOrder: Lilianae Takht., 1967
Ordo/Order: Amaryllidales Bromhead, 1840
Familia/Family: Alliaceae J. Agardh, 1858
Subfamilia/Subfamily: Allioideae Herb., 1837
Tribus/Tribe: Allieae Dumort., 1827
Subtribus/Subtribe: Alliinae Parl, 1852
Genus: Allium L. 1753
Species: Allium sativum L. 1753

Taxonomy of the Garlic (Allium sativum L.) according to APG System
Clade: Eucariotae Whittaker & Margulis,1978
Regnum/Kingdom: Plantae Haeckel, 1866
Clade: Angiospermae
Clade: Monocots
Clade: Unassigned monocots
Ordo: Asparagales
Familia/Family: Alliaceae J. Agardh, 1858
Subfamilia/Subfamily: Allioideae Herb., 1837
Tribus/Tribe: Allieae Dumort., 1827
Subtribus/Subtribe: Alliinae Parl, 1852
Genus: Allium L. 1753
Species: Allium sativum L. 1753

The ancestry of cultivated garlic is not definitively established. According to Zohary and Hopf "A difficulty in the identification of its wild progenitor is the sterility of the cultivars", though it is thought to be descendent from the species Allium longicuspis Regel, 1875 , which grows wild in central and south-western Asia.Allium sativum L. 1753 grow in the wild in areas where it has become naturalised. The "wild garlic", "crow garlic", and "field garlic" of Britain are members of the species Allium ursinum L. 1753, Allium vineale L. 1753, and Allium oleraceum L. 1753, respectively. In North America, Allium vineale L. 1753 (known as "wild garlic" or "crow garlic") and Allium canadense L.1753, known as "meadow garlic" or "wild garlic" and "wild onion", are common weeds in fields. One of the best-known "garlics", the so-called elephant garlic, is actually a wild leek (Allium ampeloprasum L. 1753), and not a true garlic. Single clove garlic (also called “Pearl garlic” or “Solo garlic”) also exists, originating in the Yunnan province of China.

Statistical and economical data
The world production of garlic has been attested in 2009 on 16.593.073 tons on a surface of 1.242.674 hectares (FAO, 2009). The main producers are: China (12,575,036 t), India (645,000 t), South Korea (375,463 t), Russia (226,670 t) and United States of America (194,230 t).
Europe is interested for 25% and has produced 304,040 t on 40.850 hectares; between the Member States of UE the Spain predominates that, with 142.400 t, produces 47% of garlic of all the European Union. Italy follows with 26,958 t (10%) and France with 19,500 t (9%). In table 1, the data regarding the garlic are reported for the main farmer of the world, with refer to the surface, the amount of production (in ponderal terms and in economic value) and to the yield.

Table 1 – Surface expressed in ectars (ha), quantity of production of bean dry in tons (t), value of the production noticed in thousands of dollars ($1000), yields, expressed in tons per ectar (t/ha), for the main Countries of the world (FAO, 2009).
Country Surface (ha) Production Yield (t/ha)
Quantity (t) Value ($1000)
Federazione Russa
United States of America

In the 2008, the Italian production was 26.800 t, obtained on a surface of 3.032 ectars (Table 2).

Table 2 - Surface and productions of garlic in Italy (ISTAT, 2008).

Regions Surface
Emilia and Romagna
Other regions

Allium pekinense Prokhanov, 1929 is one of the synonyms of the garlic.
The common names with which this species is named in the world are the following:

Botanical characteristics, biology and physiology
Botanically the garlic is a herbaceous perennial plant, but it is practically cultivated like annual (figure 1a).
The leaves (figure 1b) are basal, wrapping the stem and, on the contrary of that it happens in the onion, they do not work such as supply organs. The leaves are formed tangling round up it for along feature as well as that often they come exchanged like a cylindrical stem. The part of the not wrapping leaf have a linear form and it is wide till 3 cm, ending with one spiky tip and can catch up a total length of 80 cm.
The stem is a small plate of few millimetres thick, 2-3 cm long and 1-2 cm wide (figure 1c).
When come up, the flowers are carried from floral steles tall from the 40 up to 80 cm that carry to the top an umbel inflorescence (figure 1d). The flowers are small and they are carried on court peduncle. All the flowers, forming a head named spate, are also edible and they are most often consumed while immature and still tender being milder in flavour than the bulbs. The flowers are white tending to the red-pink and often they are not opened and they often abort still in bud.
Garlic is a plant carrying bulbs (figure 1e), cultivated for its flavour. The garlic plant's bulb is the most commonly used part of the plant. With the exception of the single clove types, the bulb is divided into numerous fleshy sections called cloves (figure 1f). The bulbs are covered with sterile membranous leaves named “sterile tunic” of different colour and having exclusively a protecting function (figure 1g).
The clove, that it represents the multiplication organ, is attacked directly to the stem. Each bulb contains from 6 to 14 cloves tight around.
The cloves freshly harvested are not able to germinate being, in fact, in a state of dormancy. To germinate they need to go through a series of physiological stages related to weather.
The cloves are used for consumption (raw or cooked), or for medicinal purposes, and have a characteristic pungent, spicy flavour that mellows and sweetens considerably with cooking.
The seeds (figure 1h) are formed very rarely. They are obtained from fertile inflorescences. The seeds are very important in genetic improvement programs in order to fix useful traits selected for progeny, according to the concepts of heritability (the fraction of the total phenotypic variance due to additive gene action).
Garlic is supplied from 40 to 60, superficial roots such as a rope that do not get a deeper knowledge beyond first 30 cm of soil. The root cluster attached to the basal plate of the bulb is the only part not typically considered palatable in any form.
The sticky juice within the bulb cloves is used as an adhesive in mending glass and porcelain in China. Dating back over 6,000 years, it is native to Central Asia, and has long been a staple in the Mediterranean region, as well as a frequent seasoning in Asia, Africa, and Europe. It was also highly-prized mostly in Egypt, it was even used as currency.

Figure 1 – a) garlic cultivated in open field; b) garlic plants, whose leaves are basal and wrapping the stem; c) bulbs cultivated while growing up in the open; d) typical inflorescence of the Liliaceae; e) plate-stem with cloves narrow and winding. We also show two young inflorescences most often consumed while they are immature and still tender, such as for Sulmona’s red garlic variety; f) closeup of a bulb with cloves wrapped in sterile leaves (tunics) that give color to garlic; g) garlic seeds obtained from fertile inflorescences.

Cultivation cycle
The bulb crop to maturity, when the leaves are partially dried, is at the dormant state, that is, unable to even germinate if placed under thermal and humidity favorable. The length of the period of dormancy depends on the variety and the storage temperature of cloves.
When the dormancy was overcome thanks to a suitable storage, place the clove into the soil gives the roots and sprouts at the expense of reserve substances accumulated in it. The phase of germination can last from a few days (spring plants) to 30-45 days (autumn plants with low thermal regimes).
After germination you have the progressive emission of the leaves, in variable number from 8 to 20, according to the cultivar, the climatic conditions and the age of the plant.
The bulbification, that is the formation of bulbils that differentiate in the axils of the leaves with foil, is induced by high temperatures and long day. The threshold values of these factors vary according to the variety.
The size of the future bulb depend on the number and size of the bulbils that constitute it, and these characteristics are related, respectively, with the number of leaves (the bulbils differ fact axils of leaves with foil) and with the leaf surface (proportional the duration of the vegetative phase and to the vigor of the plant). The little dormant varieties planted in the fall, having a long duration of vegetative growth, have higher productive potential. The bulbification ratio, that is the ratio between the maximum diameter of the bulb and the minimum diameter of the collar, increases from about 1.2 during the vegetative phase to 5 or more in the mature plants.
The beginning of the bulbification can be externally identified when the bulbification ratio is ≥ 2.
After the production of the leaves, the meristematic apex positioned at the center of the bulb-mother disk may abort or develop in the flowering stem. The formation of the flowering stem depends on the variety and environmental conditions: the varieties with strong dormancy and bulbification relatively early have a greater predisposition to bloom which is priviliged by the storage of the mother bulbs at very low temperatures (from -2 up to 2 C) and temperatures of 0-10 C combined with long day at the beginning of the bulbification.
In practice, the local populations have been selected to have a low aptitude for the formation of the flowering stem. In the case in which it is formed, the flowering stem is rapidly suppressed to avoid competition with the cloves in formation or growth. In this case, the basal part of the flowering stem, however, remains at the center of the bulb and dries.
In the final phase of the cycle, the leaves begin to turn yellow and dry progressively until the collar loses turgidity determining the sway of the leaf apparatus under its own weight.
The harvest, generally, takes place when the leaves are yellow or dry them in the upper third and with the collar still partially swollen.
The cycle of garlic is very long in relation to the climatic conditions and the variety. It start from October to February and ends from June up to July.

Photoperiodic and temperature requirements
The garlic in the resting phase can withstand very low temperatures (down to - 15 C).
The dormancy of bulbils is stopped by relatively cool temperatures: therefore, the optimal storage temperature of the bulb-mother is 7 C for about 8-16 weeks, although the optimum temperature for induction to bulbificazione is 2-4 C. The dormancy is instead induced or maintained by both the low (0-1 C) by high (18-25 C) temperatures.
Growing degree days (GDD), also called growing degree units (GDUs), are a heuristic tool in phenology. GDD are a measure of heat accumulation used by horticulturists, gardeners, and farmers to predict plant and animal development rates such as the date that a flower will bloom or a crop (such as the garlic) reach (physiological or commercial) maturity.
In the absence of extreme conditions such as unseasonal drought or disease, plants grow in a cumulative stepwise manner which is strongly influenced by the ambient temperature. Growing degree days take aspects of local weather into account and allow gardeners to predict (or, in greenhouses, even to control) the plants’ pace toward maturity.
Unless stressed by other environmental factors like moisture, the development rate from emergence to maturity for many plants depends upon the daily air temperature. Because many developmental events of plants and insects depend on the accumulation of specific quantities of heat, it is possible to predict when these events should occur during a growing season regardless of differences in temperatures from year to year. Growing degrees (GDs) is defined as the number of temperature degrees above a certain threshold base temperature, which varies among crop species. The base temperature is that temperature below which plant growth is zero. GDs are calculated each day as maximum temperature plus the minimum temperature divided by 2 (or the mean temperature), minus the base temperature. The relation is:

Taverage = (Tmax + Tmin)/2

For the garlic, the temperature base is:

Tbase = 0 C

GDUs are accumulated by adding each day’s GDs contribution as the season progresses.
GDUs can be used to: assess the suitability of a region for production of a particular crop; estimate the growth-stages of crops, weeds or even life stages of insects; predict maturity and cutting dates of forage crops; predict best timing of fertilizer or pesticide application; estimate the heat stress on crops; plan spacing of planting dates to produce separate harvest dates. Crop specific indices that employ separate equations for the influence of the daily minimum (nighttime) and the maximum (daytime) temperatures on growth are called crop heat units (CHUs). GDD are calculated by taking the average of the daily maximum and minimum temperatures compared to a base temperature, Tbase, estimated of 0 C for garlic). As an equation:
(Taverage - Tbase )

The GDD (acronymus of Growing Degree Days), the daily sum of the temperature degrees during the vegetative phase must be equal to 95 and it by the equation above
If the mean daily temperature is lower than the base temperature then GDD=0.
In practical terms, if the thermal sum is greater than zero means that the temperature was on average higher than that required for optimal growth of the species , while if the thermal sum is less than zero then the temperature was too low . Its value can be put in relation to other parameters, such as the irrigation necessary. Obviously if the sum thermal deviates too much from zero occur risks for the crop. It is rather the opposite is true , that is, a sum thermal near or equal to zero does not exclude changes in temperature, positive and negative, such as to damage the crop.
During their life cycle plants require a certain amount of heat (energy) for the various stages of their growth. The vegetative cycle duration is generally shorter the greater is the amount of energy received which is in turn correlated with the average daily temperature . You can go back then , with a certain approximation, the duration of the life cycle , knowing the amount of useful degrees of temperature for the day and the total requirements required by the plants. In addition, you may provide any advances or delays of the period of cycle growth or the bulb maturation, for example, as a function of seasonal trends warmer or colder than average.
If the daily average temperature is equal or less to vegetation zero, GDUs are not accumulate.
In synthesis and for specifying better, a degree day is a measure of heating or cooling. Total degree days from an appropriate starting date are used to plan the planting of crops and management of pests and pest control timing. Weekly or monthly degree-day figures may also be used within an energy monitoring and targeting scheme to monitor the heating and cooling costs of climate controlled buildings, while annual figures can be used for estimating future costs.
A degree day is computed as the integral of a function of time that generally varies with temperature. The function is truncated to upper and lower limits that vary by organism, or to limits that are appropriate for climate control. The function can be estimated or measured by one of the following methods, in each case by reference to a chosen base temperature: A zero degree-day in energy monitoring and targeting is when either heating or cooling consumption is at a minimum, which is useful with power utility companies in predicting seasonal low points in energy demand.
Heating degree days are typical indicators of household energy consumption for space heating. The air temperature in a building is on average 2 C to 3 C higher than that of the air outside. A temperature of 18 C indoors corresponds to an outside temperature of about 15.5C. If the air temperature outside is 1 C below 15.5 C, then heating is required to maintain a temperature of about 18 C. If the outside temperature is 1 C below the average temperature it is accounted as 1 degree-day. The sum of the degree days over periods such as a month or an entire heating season is used in calculating the amount of heating required for a building. Degree Days are also used to estimate air conditioning usage during the warm season such as in the greenhouse crop protection.
The bulbification is induced by high temperatures (18-20 C) and from day long.
The minimum duration of the day depends on the place of variety origin. The minimum thresholds for the duration of the day effective for bulbification garlic should be as follows:
- in tropical regions the length of the day should be 11.5 to 12.0 hours;
- in the South Mediterranean should be 13.0 to 13.5 hours;
- in the Central Mediterranean must be 14.0 to 14.5 hours;
- in the North Mediterannean the length of the day should be 15.0 hours.
Flowering is favoured by long days and temperatures low enough, however, below 18 C.
The photoperiodic and thermal regime during storage and field also leads to complex effects on the growth and development of garlic, with obvious repercussions on quality aspects. For example, relatively low temperatures during storage of the mother bulbs, followed by low temperatures and short day in the field (after the induction to the bulbification) predispose the plant to the formation of side shoots and bulbils and therefore of malformed bulbs; photoperiod long and high temperatures, immediately after the planting, promote the formation of a bulb consisting of a single clove of large sizes.

The garlic, being a plant sexually sterile, is unable to produce vital seed, for which it is multiplied by vegetative via (bulbils said improperly "seeds"). This has encouraged the spread of ecotypes, that is local populations, that were cultivated for a long time in the same area were mildly selected (for example, during the genetic selection, elimination of out kind individuals, not required by the market, and sick ones) and are now well adapted to certain climatic conditions and well differentiated between them.
The local people, who often take the noun or the adjective of the origin place (for example, between those Italian: White of Piacenza, Red of Sulmona, Genoa Garlic, White of Piedmont, Veneto, Pescia, Fucino, Neapolitan, Sicilian), are commonly called varieties and are now quite stable but relatively heterogeneous. The garlic varieties cultivated can be classified into 8 groups according to their biology (need in the cold for the elimination of dormancy and growth start of the axillary apex, photoperiodic requirements for bulbification) and their morphology (colour of the tunics, structure of the bulb).
Group 1 - large variety bulbs, do not form flowering stem; variable colouring with outer skins from white to mauve, bulbils from ivory white to violet. 75% of French production and about 10% of Spanish and Italian are to be included in this grouping;
group 2 - variety in medium or small bulbs, do not form flowering stem; dormancy high; staining of cloves and tunics fairly constant from white to ivory white. About 80% of Italian production, 15% of French production and small amounts of Spanish production have the varietal characteristics of this group;
Group 3 - bulb varieties of medium size, form flowering stem; dormancy medium to strong, highly variable coloration with tunics from white to mauve and cloves from ivory white to purple, sometimes striated white/red. About 10% of French production and almost all Spanish varieties fall into this group;
group 4 - varieties that have some needs in cold and require a reduced day length for bulb growth. The types of tropical mountain grown in Mexico and Peru have characteristics of this group;
5th group - varieties that have no requirement for cold and require a short day length for bulb growth. The types of tropical lowland belong to this group;
6th group - spherical variety with small bulbs formed by 4-6 cloves of good structure, often in dark red robes. Types common in the Far East belong to this group;
7th group - varieties similar to those of group 6, but with an open structure like many Chinese varieties;
8th group - cultivar similar to those of group 1, but with flowering stem, as most of the Japanese varieties.
There are numerous cultivars mostly derived from selection with the local populations. Simply we can distinguish them in garlic with white tunic and with red tunic.

• Varieties with white tunics, with silver-white tunics, regular bulbs with 14-15 cloves, late, to strong dormancy, suitable for autumn plants. They are the most common types (representing approximately 90% of the garlic grown) due to the considerable size, good and constant production and adaptability to different environmental conditions:
- “White of Piacenza” or “Ottolini garlic” (figure 2);
- “Big Venetian”;
- “White of the Fucino”;
- “White of Naples” (figure 4);
- “White of Calabria”;
- “White Polesano”;
- “White of Voghiera” (figure 5), white bulbs with bright and uniform.

•Varieties with a pink tunic, with bulbs less regular than white and consist of several bulbils (more than 20). It is not much preservable for which it is consumed fresh. It is earliest of the white garlic of about 20 days and it has less than the dormancy characteristics. It has limited diffusion and it is considered less valuable of the white garlic. At this varieties belong to the following types:
- “Pink Neapolitan”;
- “Garlic of Vessalico” (figure 6);
- “Pink of Agrigento” (figure 7).

•Varieties with a red tunic:
- “Red of Sulmona” (figure 8 and figure 9), it is an ecotype that has intermediate characteristics between the two groups because it has the outer skin of the bulb white, while those of cloves of purple, this ecotype always develops the flowering stem that is removed and eaten fresh.
- “Red of Nubia”: from the name of a district of Trapani, it is Slow Food presidium. The bulb typically consists of twelve cloves, with white outer tunics and the internal tunics of bright red. It is traditionally packaged in braids for about one hundred bulbs. Starting from the local population in the past decade has begun a systematic selection that gave rise to clonal varieties are characterized by a more uniform morpho-biological characteristics, good productivity, good storage, no virus thanks to the work of restoration techniques facilitated by in vitro culture. An example of what is now called the variety Serena White of Piacenza.
The main varieties officially listed in the Italian National Register and selected from national ecotypes are:
- “White of Piacenza" (figure 2), medium-late varieties of garlic (maturing from July 7 up to 15), medium size and regular, average production of about 10 t/ha of dry matter, long-term storage in the refrigerator, pronounced flavour, planting in October. It is perhaps the best white garlic good size grown in Italy, famous for its quality of taste and good shelf life. It contains high amounts of allycin and essential oils that make it an excellent aid against many diseases such as hypercholesterolemia and against the increase in blood pressure;
- “Red of Sulmona” (figure 8 and figure 9), a variety with white bulb and with red cloves, the presence of flowering stem , medium-early maturing (20-30 June), medium size and smooth, discreet productivity (6.5-7 t/ha of dry product), good storage in the refrigerator, spicy aroma and flavour, planting in late November to December;
- “Serene”, a medium-late variety of garlic (maturing July 10 to 17), virus-free, regular and large size, good production potential (12-14 t / ha), long-term storage in the refrigerator, pronounced flavour, “sowing” in October;
- “Cristop”, of French origin, garlic white medium-late (maturing July 5 to 15), the presence of the flowering stem , size medium-large and irregular, good production, media storage in the refrigerator, pronounced flavour, “sowing” in October. The variety is free from viruses.

Figure 2 – “”White of Piacenza””, l’ ecotype more widespread in Italy.

Figure 3 - "White of Monticelli" has obtained the designation of protection originated under Regulation (EEC) No. 2081/92. The area of production and packaging of this garlic ecotype falls in the province of Piacenza and includes the entire territory of the municipalities of Besenzone, Cadeo, Caledon, Caorso, Castelvetro, Cortemaggiore, Fiorenzuola Gossolengo, Gragnano Trebbiense, Monticelli, Piacenza, Podenzano, Pontenure, Rottofreno, Sarmato, San Pietro in Cerro, Villanova and part of the territory of the municipalities of Agazzano Alseno, Borgonovo Val Tidone Carpaneto Piacenza, Castell'Arquato, Castel San Giovanni, Gazzola, Ponte dell'Olio, Rivergaro, San Giorgio Piacentino, Vigolzone.

Figure 4 – “White of Naples”, a cultivar characterized by pink tunics and a high content of essential oils. Garlic di Naples mature in June and traditionally it is harvested in occurs on the religious feast of St. Anthony of Padua, June 13. After harvesting, the bulbs are cleaned and left to dry for about ten days until June 24 feast of St. John, we proceed interweaving of traditional plaits, which can be found in every Naples home.

Figure 5 – “White of Voghiera”, a cultivar of Ferrara, which produces more than 50% of the production of the whole Province. The product has a good size and homogeneous, the colour is bright white and the yield per hectare is good and now coming up to about 100 q. In 2000, it were formed the Consortium of Producers of the Voghiera’s Garlic. The objectives of the Consortium are: to treat the study of the method of production, reducing costs and streamlining processes, promote agricultural experimentation and research programs directed to the enhancement of the garlic; promote agricultural experimentation and research programs directed to the productive reconversion of associated companies for retrofitting; cure, in collaboration with national, regional and local Services, the diffusion of data and information.

Figure 6 – “Vessalico’s Garlic” is a cultivated variety in the 11 municipalities that make up the territory of the Arroscia Valley. The name is related to the Fair (Fera) which is held in the valley in the municipality of Vessalico (a document Liber Decretorum Communitatis Vessatici makes it back to the year 1760). The main features of this variety are the intense aroma accompanied by a delicate taste, garlic is a very digestible and has a good shelf life. These characteristics are given by the mild climate (the Arroscia Valley lies at the foot of the Alps, at the same time still suffers from the influence of the climate of the Ligurian coast) and from soils particularly suited to this crop. “Vessalico’s Garlic” has a compact bulb consists of an average of ten cloves, with the outer tunics of white-pink (with red-purple streaks just harvested) and the cloves in white. This variety of garlic has not inflorescence.

Figure 7 – “Agrigento’s Pink Garlic” has outer tunics white-pink. The shape of the bulbs is huge, with more than 20 segments, smaller and less regular than white garlic, fresh and consumed mainly because it has less shelf life, about 3-4 months.

Figure 8 – "Red of Sulmona" is an ecotype grown for centuries in Abruzzo (Peligna Valley) in the province of L'Aquila (whose main centre is Sulmona). It is a product of excellent quality, well appreciated in the market, which has given rise to high export flows, but has followed the downward trend of the culture in Italy, where the surfaces are reduced and are now estimated at about 150 hectares. The marketable production is 10,000 q of dry product with a value of approximately € 2 million. In this situation, was born in July 2009, the Consortium of Producers that promotes all efforts to defend, protect, enhance and commercialize garlic “Red of Sulmona”. The results achieved in just 3 years of work demonstrate that the path is re-launching and qualifying the production “Red of Sulmona” garlic.

Figure 9 – The typical braid of the variety "Red of Sulmona" garlic. In fact, this particular variety of garlic is processed in braids with 54 heads of two lines, which are then hung in the pantry, such as it is done with the chilli pepper. The "Red of Sulmona" has characteristics that qualify the national level. Its name comes from the colour of the last tunic that protects the clove, which is a nice red colour intense wine, with homogeneous diffusion and strong, but it can also yellowish-white streaks more or less marked. The conformation of the bulb is regular and well tightened its consistency, for which are absent the supernumerary cloves or those extratunicates. Maturation takes place between the third week of June and the first half of July, in an intermediate period of harvest between the pink garlic of the Southern Italy and those white ones of the North. The shelf life at room temperature is high, so that the bulb is kept firm and compact until the following spring and they have a delayed pre-shooting. The ecotype is known in Italy for the high spiciness and aroma due to its high content in essential oils typical of garlic (disulphide and diallyldisolphure), which provide both a flavour organoleptic specific that high pharmacological properties. Finally, it is the sole Italian variety in which the regular issue of the flowering stem, which can be eaten both fresh both in oil.

Garlic hailing from abroad
“Pink of Lautrec” French garlic (figure 10)
Probably originated from a local mutation of plants. Legend has it that the plants were given in exchange for a meal to be a pilgrim without money passed through Lautrec. The pink garlic of Lautrec French is sometimes marketed in Italy as pink garlic. It is a misconception, because the garlic with trade mark named “Label Rouge” since from 1966 - the first certification system for quality products applied in France - comes from an area of about 360 acres on the slopes of clayey limestone of the Tarn, where Lautrec is the most important City. Area with mild climate, thanks to the double influence of the Mediterranean Sea and the Atlantic Ocean where the pink garlic is cultivated since the Middle Ages. Since 1996 this garlic obtained the IGP trade mark. The features of this product certainly justify the price high: sweet and intense aroma without being aggressive, with low persistence over time, therefore can be used without problems known as social consequences. The slogan with which it is advertised Ne dites pas ail avant de l'avoir gout (do not say garlic up to you have it tasted).
The heads of garlic are regular and full, with well separated cloves, strong and suffused pink colour, listed by darker signs.
The plant must be removed from the ground whole, without being deprived of leaves and roots, and hung to dry in a ventilated and shaded, where will lose a quarter of its weight. Only when the cloves are ready, the roots and the leaves are eliminated, except the last which allow to keep the head cohesive without hiding the colour.
At this point we package in manouille, not in braids, but in bunches with stems of different lengths side by side so as to obtain the same effect of the braids. The drying process is natural and takes long time, but allows to keep the cloves still full from year to year.
To give garlic its distinctive characteristics are essentially four elements:
- The starting material.
- The mild climate that allows for early cultivation.
- The nature of the soil clayey limestone.
- The conformity with the instructions of cultivation indicated by the product specification.
The seeds produced by flowers are sterile so the pink garlic is grown only from the cloves, which must be placed in the ground in the months of December and January. At the beginning of the month of June provides, through plant to plant, to remove the flowering stem. The harvest is make at the end of the month. In the cultivation of the crop, the main operation that weed control should be carried out with a light hoeing the soil and eliminating manual. The hoeing also serves to break the crust of the soil that can be formed with the swing action of the rain, keep soft and permeable soil, interrupt the capillary rise of water from the deep layers.
The irrigation is carried out only during periods of water scarcity, always wet the foot of the plants with small quantities of water, and never saturate the soil. Do not water the crop in the vicinity of the harvest. All operations should be conducted avoiding to compact the soil by pounding.
Figure 10 – “Pink of Lautrec” French garlic. We observe the typical braid adopted for this French variety, obtained by tying bunches of garlic with different length of the stems.

A special type of garlic is that belonging to the range Black Garlic product by the English organization. Black garlic (Figure 11) is obtained by letting the garlic fermented at high temperatures for a few weeks, it tastes spicy and balsamic, but leaves no aftertaste garlic typical and bad breath, it has double the amount antioxidants, compared to the normal garlic, low in fat and is rich in natural sugars. In general, the strength of this product is that its production process is completely natural, without the use of preservatives or other chemical additives added, presenting a long shelf life. Moreover, its essential trace elements are multiplied exponentially (up to 10 times!) by the fermentation process. This manufacturing process finish in approximately thirty days and decreases 97% the typical pungent flavour. The final product has a sweeter flavour profile, reminiscent that of a plum.
The black garlic is used as an ingredient in all kinds of dishes, like a spice, although it can also be eaten raw. The range of the Black Garlic consists of bulbs (both single and double pack), peeled in jars from 50 to 150 grams and will soon be introduced on the market the cream of black garlic. The company currently imports wholesale product from the United States and then package it in the United Kingdom (Figure 12). Black Garlic supplies when the chains Tesco, Waitrose, Sainsbury's and Budgens, as well as many individual firms in England. The number of wholesalers is continuing to grow.
Figure 11 – Garlic of the range od Black Garlic, presented to the Fruit Logistica in Germany (Berlino, february 8-10, 2012).

Figure 12 – Method of packaging of the range Black Garlic.

Between the end of July and throughout the month of August 2013 has arrived in Italy Chinese garlic, without, however, meet with great enthusiasm, as the prices are lower than garlic of national origin and to import Spanish, although not in a significant. It also notes a growing alienation of the consumer against Chinese garlic, although the price is lower, the preference is always more to Italian products and the Spanish one. By now, the biggest consumers of Chinese garlic are the countries of Northern Europe, mainly Britain.
The Spain is the main country from which the Italy imports garlic. The Spain this season has produced a good quality product and good gauge of the type variety Spring . However, the contrary, the varieties of garlic traditional white again present problems of drying and curing, due to the phenomenon known as "Waxy Breakdown", attributable to infection by Fusarium proliferatum , now generalized and evident in three producing countries (Spain, France, and Italy). This rot is still widespread exclusively white garlic and not the kind of red or pink. Quality problems, but of a different nature, they are also found on the variety "Morado" in Spain, with the presentation of bulbs quite irregular and deformed with few coats of finish and colour of the coating films of the segments very faded and tending to white. In practice, the characteristics that differentiate these varieties from garlic white this year are less obvious and so the market is experiencing a decrease in the selling price and low demand.
The average import price in 2013 varies around 1.00 to 1.50 €/kg, depending on the caliber and quality class. The demand is still low and the interest in the product is really non-existent.
The future prospects are the biggest problem and the great unknown of the segment. First of all, this year there will be enough unsold product and the average farmer will surely be tempted to replant it, a likely result of a further increase in production not only in Europe but also in China, where the great production this season has created the same issues of European market.
In addition, the phenomenon of the spread of "Waxy Breakdown" is moving more and more towards the choice of farmers variety of early type and is creating some concern in the purchase of seed certified free of viruses which, however, does not guarantee safety production and the subsequent placement of this market. Until September of 2013 are still available quantities of garlic of the last campaign, both Spanish origin, both Argentine, so to sell old stocks, the price will decrease even at the expense of the product of the new crop. Easily it is expected a surplus of goods which can be marketed in the coming year, if well maintained in the fridge.
The new crops of South America (Figure 13) will be available before the end of the year. If the European market will not be able to absorb this product definitely not worth it to import it. Operators who in the last campaign imported garlic from Argentina have had to cope with major losses, so you have to wonder if it is worth to realize new imports.

Figure 13 – Import of garlic from Argentina. The production of Italian garlic barely meets 20% of domestic needs. The bulk of consumption is met by garlic imported mainly from abroad, and particularly from China, Spain, Argentina and from third countries in the Mediterranean. At this time in the domestic market and is available only Argentine garlic, in small part, of the former Italian countryside, which had been preserved and the stocks of which, incidentally, are now being depleted.

In concluding this section on types of garlic imported must report on an abnormal form of commercialization of this important plant vegetable garden. The garlic import is subject to a customs duty of 9.5% and this has caused a boom in illegal trafficking to evade taxes giving rise to crime, which unfortunately is very profitable in the European Union. According to the European Anti-Fraud Office is the China (the main producer of garlic, with a global share of 80%), the country star of this black market, which is concentrated mainly in Great Britain, Italy and Poland. Therefore, it is desirable that the points of sale of this product will ensure the quality of fruit and vegetables, inviting will choose rigorously the Made in Italy (Figure 14).
Figure 14 – Commercial kits and packages of Italian garlic (top and center) and workers who work on the industrial process (below).

Soil environment
The recommended values for the soil parameters, referring to the rhizosphere, for garlic cultivation are the follows:
Climatic environment
The recommended values for the climate parameters in the cultivation of garlic are as follows:
The minimum interval between two successive cycles must not exceed 4 years. The crops are not recommended in the lawn and precession are those who keep pests such as sclerotinia garlic and nematodes.

It is recommended during the summer a plowing up to 40 cm combined with subsoiling in case there are problems of poor drainage.
It is recommended that the preparation of the seed bed, with harrows during the months of July-August for the summer-autumn sowing.

It is recommended that the choice of implant technique in relation to of the:
It is recommended sowing manual which gives the best yield of production, even if, from the economic point of view, this technique, which allows a greater yield in the order of 13-14 quintals per hectare, it is not easy to implement for the increased need labor (Figure 15) . The "seeding" is performed by hand, using bulbils from bulbs healthy, free from rotting, of average weight above 2 g, disposed with the apex pointing upwards, at a depth of approximately 5 cm. The cloves are placed on small furrows previously performed with a rotary tiller equipped with a small furrow opener. II budding occurs at the expense of reserve substances and is more rapid when the cloves are large and at a temperature of 15-20 C. For the investment of an hectare of garlic are needed q 6-7 of cloves in average. The planting distance can vary from 10 to 15 cm on the row and from 25 to 40 cm between rows, in relation to the mechanization of the farm.

Figure 15 - Manual "seeding" of cloves placed in the soil with the apex pointing upwards, at 5 cm depth.

For mechanical planting we recommend the use of the following machines:
- Semi-automatic drill-seeder: involves the use of five working units that they drop the cloves by adductor pipes in furrows which are then covered;
- Seeder automatic, pneumatic type, which distributes the cloves by controlled pressures, through adductor pipes, in furrows (figure 16).
It should also be emphasized that, while with the planting manual it is arranged in the in furrows where the cloves with the radical part facing downwards, with the seed, usually, the clove have randomly, mostly horizontally or sometimes inverted, with the so that, in the process of germination, the seedlings often have trouble getting the right position.

Figure 16 – Mechanical pneumatic seed drills for sowing of garlic cloves. The use of these machines ensures uniformity of sowing and a considerable saving of manual labor. However, their use often causes a delay in the emergency, since the bulblli are placed, randomly, in different positions. However, this does not reduce the productive yield.

Propagation material
As propagation material we recommend the use of cloves obtained by shelling the bulbs. For the shelling, which must be done a few days before planting, we recommend the use of special equipment or handicraft of high precision. An essential element of this outfit is the heating of the cloves before shelling (which restricts problems microferite). Once shelled it is advisable to clean the cloves from the roots, outer tunics, cloves and bulbils external power to the bulb (teeth). Normally the cloves are not permitted because the production is downgraded.

Disinfection of bulbils
Once the cloves have been cleaned up it is advisable to disinfect them with specific formulations to prevent it in the ground , especially if wet and very low temperatures , are infected by parasitic fungi ( Penicillium spp ) leading them to death. We recommend cleaning or disinfecting bath (Figure 16).

The planting pattern, the density of the investment and the depth of planting represent some important parameters to consider with the garlic planting. If the soil prepared for planting is very loose and dry before you start planting the garlic cloves is advisable to perform a soil roll to make it more compact and more leveled and accordingly apply the desired planting depth.
The particulars of the planting pattern and the depth of the plant are:

Nutritional requirements and mineral fertilization of garlic
The purpose of fertilization is ensure the availability to the garlic cultivation during the entire life cycle, the primary nutrients in amounts and in forms appropriate to the plant and in compliance with the quality requirements of the product and of the environment.
Nitrogen, in general, causes to an increase in the vigor of the plants with the early growth of the vegetative apparatus, a prerequisite for obtaining high production. An excessive availability of this element in the soil retards the bulb growth and at the end of the cycle delays the ripening of the bulbs and decreases its shelf life. With nitrogen deficiency, however, the leaves are growing much more slowly, developing a light green color and a more erect deportment, having a more rapid senescence and the formation of bulbs is accelerated.
The deficiency of phosphorus and potassium cause stunted growth, more rapid leaf senescence, delayed maturation and lateness of the harvesting, formation of bulbs with short appressed tunics, with a low dry residue and scarce life-shelf.
The availability of sulphur in the soil promotes the synthesis of sulphur compounds responsible for the characteristic flavor and aroma of the garlic, although it appears that the absorption of sulphur causes a depressive effect of ammonium ions and chlorine, which therefore tend to sweeten the bulbs.
Buyers indicative nutrients garlic (kg of nutrient per tonne of bulbs) are shown in Table 3.

Table 3 - Requirements for principal nutrients of garlic cultivation (kg of nutrient per tonne of bulbs).
Nutrient kg/t of bulbs
Nitrogen (N)
Phosphorus (P2O5)
Potassium (K2O)
Calcium (CaO)
Sulphur (S)
Magnesium (MgO)
10,0 ÷ 11,0
3,0 ÷ 4,5
8,0 ÷ 10,0
2,5 ÷ 3,0
1,0 ÷ 5,0
0,1 ÷ 0,5

The rate of nutrient absorption is not uniform throughout the cycle of the crop, but varies with the different phenological stages. The demand for nitrogen is high especially during the vegetative stage of formation and emission of the leaves and then become very moderate during the bulb growth. In the final stage of the nitrogen cycle it is even harmful to the delay of ripening and for the reduction of shelf life of bulbs. Buyers of phosphorus and potassium, however, are particularly high in the phase of bulb magnification and increasing the sizes.
The knowledge of the physico-chemical characteristics of the soil is essential to establish an adequate program of fertilization and the need to verify whether or not fertilization enrichment. While the physical-mechanical analysis can be made ​​only once, the chemical should be repeated at least every 3-4 years.
By inserting the fertilization of garlic in the balance of fertilization of the rotation, you have to take into account that the crop residues (leaf blades) represent more than 15% of dry matter, or are insignificant. Therefore, with reference to the requirements calculated for an expected production of 10 t/ha, equivalent to 110 kg/ha of N, 45 kg / ha of P2O5 and 90 kg/ha of K2O, these quantities of nutrients need to be considered all effectively removed from soil with bulbs.
Then it will be analyzed in more detail the fertilizer relative to the three macronutrients following a chronological order of application: first, phosphorus and potassium with the basic fertilization and after with the nitrogen fertilization in the vicinity of the plant and/or soil coverage.
In garlic organic fertilization is not recommended because it increases the sensitivity of the bulbs to different rot agents and causes disruption of nitrogen nutrition in the final phase of the cycle with delayed of ripening and deterioration of shelf life.

The dose to be administered should be determined on the basis of the allocation of available phosphorus in the soil. Therefore, it is necessary to perform the chemical analysis of the soil in order to measure, in the layer of soil affected by the roots of the garlic the amount (in ppm) of total phosphorus (P) and of assimilable phosphorus (P2O5) and then to perform an assessment agronomic about the quantitative level of nutrient useful for garlic plants. The levels are as follows, in view of the fact that the values ​​expressed in ppm (parts per million), lower interval refers to sandy soils, loamy soils in the higher ones, to medium soils assume intermediate values:
  • Very low level of phosphorus (06 ppm of P and 015 ppm P2O5): the response to phosphate fertilization is certain for all crops. It is recommended fertilization enrichment, with doses ranging from 2 to 2.5 times the excise culture. Fertilization enrichment must continue until you reach the level of sufficiency for all crops in the rotation.
  • Low level (7 to 12 ppm P and 16 to 30 ppm P2O5): the response to phosphate fertilizer for all crops is likely. The fertilization is recommended that enrichment; doses to be made vary from 1.5 to 2 times the excise culture.
  • Intermediate level (13 to 20 ppm P and 31 to 45 ppm P2O5): the response to phosphate fertilization is less likely. It is recommended maintenance fertilization: they must be reinstated the excise culture with any increases (up to 1.5 times the excise) to account for the fraction of available phosphorus that, in almost all soils, undergoes retrograde to the presence of limestone or for pH <5.5.
  • High level (21 to 30 ppm P and 46 to 70 ppm P2O5): the response to phosphate fertilization is generally not likely, but it is suggested that a moderate intake of phosphorus for crops demanding for this item. The doses to be made to vary from 0.5 to 1 time the excise culture.
  • Very high level of phosphorus (>70 ppm P2O5): the response to phosphate fertilization is unlikely, therefore it is advisable not to administer the basics of phosphorus fertilizers. The allocation of available phosphorus in the soil can be considered normal when it meets the needs of all crops in the rotation, starting with the most demanding. Considering the low mobility of this element, it is good to bury the entire dose would be working with the principal to bring in the layer of soil affected by the mass of roots. To accelerate the development of the root system and the initial growth of the crop, it is recommended to apply a starter fertilizer. Such fertilization is generally carried out with ammonium phosphate at a dose of about 50 kg/ha of phosphorus pentoxide, suitably localized below the seed and seedling.

    The needs of the garlic for this element are averages and the maximum requirements on verify during the enlargement of the bulb.
    The doses required are not high or low but medium and must be calculated, such as for the phosphorus, considering the allocation of land in exchangeable potassium and agronomic evaluation of the chemical analysis of the soil provides this envelope, in relation to the needs of the crop. The table shows the following levels of potassium, expressed in ppm and CEC (Cation-Exchange Capacity ) that is the amount of exchangeable cations, expressed in milliequivalents per 100 grams (meq/100g), that a material with adsorption properties may retain for ion exchange:
  • Very low level of potassium (0 50 ppm of K and 0 to 60 ppm of K2O). The response to potassium fertilization is certain. It is recommended the enrichment fertilization with doses of 1.1 to 1.5 times the potassium removals from the garlic culture.
  • Low level (51 100 ppm of K, 61 to 120 ppm of K2O, < 2% of CEC as K CEC % ). The response to potassium fertilization it is probable for all crops. Fertilization recommended it is that of enrichment with doses ranging from 0.8 to 1.1 times the removals of the garlic culture.
  • Intermediate level (101 150 ppm of K, 121 to 180 ppm of K2O, 2 % to 5 % CEC as K CEC %). The response to potassium fertilization is generally unlikely . The fertilization is recommended is that of maintenance doses of 0.5 to 0.8 times the removals of the culture.
  • High level ( 151 200 ppm K, 181 to 240 ppm of K2O, > 5 % CEC as K CEC %). The response to potassium fertilization is not, in general, likely, so you should not fertilize. The potassium may be necessary for demanding crops and capable of high production , the dose should not exceed 0.5 times the the removals of the culture.
  • Very high (> 200 ppm K, > 240 ppm K2O). the response to the administration of potassium fertilizers is highly unlikely and, therefore, you should not fertilize. Considering the low mobility of this element, it is good to bury the entire dose would be working with the principal to bring in the layer of soil affected by the mass of roots.

    Nitrogen is the nutrient that most influences the production of garlic. The use of nitrogen fertilizers, however, unlike what happens with those phosphatic and potassic, requires particular attention, especially in determining the optimal dose to be administered, because incorrect interventions, both in defect is in excess, are paid in terms of loss of quantity and/or quality of the production.
    In addition, the high degree of mobility in the soil of certain forms of nitrogen makes it necessary precautions to protect the environment (pollution of groundwater by nitrate nitrogen). The nitric form, finally, can accumulate in the tissues of plants, including edible parts, causing health risks to consumers. Nitrates, in fact, once ingested can be transformed into nitrite which, in turn, may combine with free amines and form nitrosamines, carcinogenic compounds. Garlic fortunately has a low tendency to accumulate nitrates in the bulb. Despite numerous studies on nitrogen balance in agriculture, we must say that is not easy to find a sufficiently simple and accurate method to determine the doses of nitrogen to be distributed to a culture.
    The need for nitrogen fertilization can be calculated as the difference between the amount collected by the crop during the crop cycle and the amount of mineral nitrogen available in the soil at the beginning of the cycle more than that becomes available during the spring and summer, for mineralization humus and crop residues incorporated into the soil. In addition, one must consider that not all the nitrogen fertilizer is distributed absorbed by the plant, but depending on the type of soil, the climatic conditions, the formulation used (fertilizers, slow effect) and the mode of distribution (in all over the field, in bands, fertirrigation) the absorption efficiency of nitrogen fertilization may also vary widely so the dose technique made must be suitably increased. From the above it follows that: Nitrogen is the nutrient that most affects the production of garlic. The use of nitrogen fertilizers, however, unlike what happens with those phosphatic and potassic , requires particular attention , especially in determining the optimal dose to be administered, since errors, both in the defect is in excess, are paid in terms of loss of quantity and / or quality of the production. In addition, the high degree of mobility in the soil of certain forms of nitrogen makes it necessary precautions to protect the environment ( pollution of groundwater by nitrate nitrogen ) . The nitric, finally, can accumulate in the tissues of plants, including edible parts , causing health risks to consumers. Nitrates , in fact, once ingested can be transformed into nitrite which , in turn , may combine with free amines and form nitrosamines , carcinogenic compounds . Garlic fortunately has a low tendency to accumulate nitrates in the bulb . Despite numerous studies on nitrogen balance in agriculture , we must say that is not easy to find a sufficiently simple and accurate method to determine the doses of nitrogen to be distributed to a culture . The need for nitrogen fertilization can be calculated as the difference between the amount collected by the crop during the crop cycle and the amount of mineral nitrogen available in the soil at the beginning of the cycle more than that becomes available during the spring and summer , for mineralization humus and crop residues incorporated into the soil. In addition, one must consider that not all the nitrogen fertilizer is distributed absorbed by the plant , but depending on the type of soil, the climatic conditions , the formulation used (eg fertilizers, slow effect ) and the mode of distribution ( in all over the field , in bands , fertigation ) the absorption efficiency of nitrogen fertilization may also vary widely so the dose technique made ​​must be suitably increased. From the above it follows that:

    Nitrogen fertilization = (taken N - available N) / Efficiency fertilization

    It is been said that, for an expected production of 10 t/ha, the crop must have access to approximately 110 kg of nitrogen. In ordinary conditions, for example in the case where the preceding crop is represented by wheat, which is known to leave a reduced amount of residual nitrogen in the soil, and the organic matter content of the soil is relatively poor (1-1.3 %), is can therefore reasonable to estimate that the crop has available in the soil about 50-70 kg/ha of nitrogen for which the remaining 40-60 kg/ha should be made with fertilizing. If one considers that, because of the radical apparatus surface, the absorption efficiency of nitrogen fertilization with distributions all over the field is approximately 50%, it will be necessary to increase the dose up technique to make about 80-120 kg/ha of nitrogen.
    Obviously, the dose to make changes if they change the terms of nitrogen balance:
  • Late cultivars were irrigated and growth, production requirements and higher.
  • Crop residues of precession may contain varying amounts of nitrogen, which may in part be available at the beginning of the cycle.
  • If it applied a starter fertilizer, the greater development of the root system increases the efficiency of nitrogen uptake.
  • Similarly, if the distribution of nitrogen fertilizer is localized in bands along the row the absorption efficiency increases. In order to follow the rhythms of absorption of the crop, reducing the risk of leaching and to avoid an excess of nitrogen in the maturation phase of the bulbs, the intended dose of nitrogen should be fractionated into 3 times: 1/3 to the planting, 1/3 to the stage of 3-4 leaves, and 1/3 with at enlarged of the bulbs.
    The most commonly used nitrogen fertilizers are ammonium sulphate plant (also to make sulfur) and ammonium nitrate or urea in coverage.
    Finally, it should be noted that fertilization must be carried out exclusively with mineral fertilizers and not organic fertilizers because this last can cause plant root rot. Therefore, you should make a organic fertilizer to the previous crop garlic.

    Water requirements and irrigation
    In the early stages of growth the garlic do not need irrigation.
    The satisfaction of crop water requirements is a key factor both in terms of quantity and quality of production.
    Insufficient availability of water, in fact, entails a reduced growth, the increase of bulbs undersize and in summary lower production. On the contrary, an excess water is a waste of water, it causes the leaching of nutrients and phenomena of asphyxia of roots, promotes a greater susceptibility to pest attacks, and if it occurs in the final phase of the cycle, a retardation of ripening, a worsening of the shelf life of the bulbs and the qualitative characteristics such as lowering of the dry aroma and distinctive flavour, less "dressing" (tunics) of the bulbs.
    In our growing environments, the rains that fall in autumn, winter and spring are generally sufficient to meet most of the water needs of the crop (which in our environments, it is estimated that on average in 1.500-2.500 m3/ha).
    During the enlargement of the bulb, which occurs during the spring period (April-June ) may be required, depending on the growing environment and the seasonal trend, 2-3 irrigation interventions with individual volumes of irrigation intervals of about 400 m3/ha. Do not water in the vicinity of the harvest.
    Research carried on garlic irrigation have shown that:
  • Water requirement = 425 mm.
  • No difference in yield between 100 and 125% ETc.
  • Significant difference below 100% ETc.
  • Peak Kc (Crop coefficient) = -1.3.
    Data regarding the effects of different irrigation type on garlic cultivation they are reported in Table 4.

    Tabella 4 - Means of soluble solids and bulb weight by irrigation system.
    Irrigation Type Soluble Solids (%) 100 Bulb Weight (kg) SE (bulb weight)
    Surface Drip
    Subsurface drip
    SE (SS%)
    35.94 a
    35.58 a
    36.89 b
    4.82 a
    4.98 ab
    5.22 b
    Means not followed by the same letter are significantly different (p<0.5) by Tukey’s multiple range test.

    Market Yield, total weight, cull weight an soluble solids by irrigation level they are reported in Table 5.

    Table 5 - Market yield, total weight, cull weight an soluble solids by irrigation level.
    Irrigation Level
    (% ETc)
    Market Yield
    Total Weight
    Cull Weight
    Soluble Solids
    *Significantly < 100% ETc by Dunnett’s one tailed test (p<0.05).

    Irrigation has been around for as long as humans have been cultivating plants. Man's first invention after he learned how to grow plants from seeds was probably a bucket. Ancient people must have been strong from having to haul buckets full of water to pour on their first plants. Pouring water on fields is still a common irrigation method today, but other, more efficient and mechanized methods are also used.
    Early man would have used this "low-tech" method of irrigating crops. Collecting water in a bucket and pour it onto the fields. Today, this is still one of the most popular methods of crop irrigation. The system is called flood irrigation. Water is pumped or brought to the fields and is allowed to flow along the ground among the crops. This method is simple and cheap, and is widely used by societies in less developed parts of the world. The problem is, about one-half of the water used ends up not getting to the crops. Traditional flood irrigation can mean a lot of wasted water.
    A large part, about 70%, of all the fresh water used in the world goes to irrigate crops. After use, much of this water cannot be reused because so much of it evaporates and transpires in the fields. If you consider that the majority of irrigation occurs where water is relatively scarce, you can see how important it is for farmers to find the most efficient methods of using their irrigation water.
    Here are some things that farmers are doing to be more efficient:
    • Leveling of fields: flood irrigation uses gravity to transport water, and, since water flows downhill, it will miss a part of the field that is on a hill, even a small hill. Farmers are using leveling equipment, some of which is guided by a laser beam, to scrape a field flat before planting. That allows water to flow evenly throughout the fields. (Actually, this method of levelling a field is also used to build flat tennis courts).
    • Surge flooding: traditional flooding involved just releasing water onto a field. In using surge flooding, water is released at prearranged intervals, which reduces unwanted runoff.
    • Capture and reuse of runoff: a large amount of flood-irrigation water is wasted because it runs off the edges and back of the fields. Farmers can capture the runoff in ponds and pump it back up to the front of the field where it is reused for the next cycle of irrigation.
    For irrigating fruits and vegetables the drip irrigation method is much more efficient than flood irrigation. Water is sent through plastic pipes (with holes in them) that are either laid along the rows of crops or even buried along their rootlines. Evaporation is cut way down, and up to one-fourth of the water used is saved, as compared to flood irrigation.
    Spray irrigation is a more modern way of irrigating, but it also requires machinery. This system is similar to the way you might water your lawn at home - stand there with a hose and spray the water out in all directions. Large scale spray irrigation systems are in use on large farms today. These systems have a long tube fixed at one end to the water source, such as a well. Water flows through the tube and is shot out by a system of spray-guns.
    A common type of spray-irrigation system are the center-pivot systems. They work in the same way you might water your yard. If you placed a faucet in the center of your yard, you could take a hose, punch holes all along it, and attach a spray gun at the end. Turn the water on, pull it tight, and start spraying (water is also spraying from the holes in the hose at the same time). While you are spraying you are also walking around in a circle (with the faucet at the center of the circle). Using this method you can get a very large circle of lawn watered with just a short hose.
    The center-pivot systems have a number of metal frames (on rolling wheels) that hold the water tube out into the fields. And there can be a very big water gun at the end of the tube. Electric motors move each frame in a big circle around the field (the tube is fixed at the water source at the center of the circle), squirting water.
    If you've been in an airplane you can easily locate center-pivot irrigation systems on the ground. You can't miss them, just look for green circles of irrigated land below.
    Better spray irrigation is by use of traditional spray irrigation, water basically is just shot through the air onto fields. In the dry and windy air, a lot of the water sprayed evaporates or blows away before it hits the ground. Another method, where water is gently sprayed from a hanging pipe uses water more efficiently. This method increases irrigation efficiency from about 60% (traditional spray irrigation) to over 90 percent. Plus, less electricity is needed.

    Hoeing and Weed Control
    Hoeing is best done when the weeds are very small seedlings or newly emerged shoots of perennial weeds. This allows shallow hoeing to kill the weeds without bringing new seeds to the soil surface. Shallow hoeing also reduces root damage to the crop. Stirrup hoes (shuffle hoes) are ideal for shallow weeding. A garden rake moved in an oval motion covers large areas. Traditional chopping type hoes are sometimes useful for hacking back weeds in untilled corners of the garden, but in loose soil they tend to dig too deep, damage crop roots and bring up more weed seeds. If the weeds are so large that a traditional hoe is needed, hand pulling or digging them out may be more efficient in the long run.
    One objective of hoeing should be the creation of a dust mulch. This is a layer of very loose soil crumbs, typically 0.5 to 1.5 inches thick. It can be achieved with most tools that work the soil shallowly including a rake, garden claw or stirrup hoe. Weeds seeds need good contact with the soil for germination just like crop seeds. Since most individuals of most annual weed species emerge from the top inch of soil, maintenance of a dust mulch greatly decreases weed density. Obviously, a dust mulch is impossible to maintain during wet weather, but when it is feasible, a dust mulch is a highly effective weed management technique.
    Hoeing is best done when the soil is slightly dry and the weather is warm and sunny. First, such conditions are ideal for drying out uprooted weeds and producing a dust mulch. Second, the hoeing will do less damage to soil structure under such conditions than when the soil is wet. Third, hoeing in rainy, or foggy conditions is likely to spread disease, both on your clothing and by bringing soil into contact with crop foliage.
    The performance of mechanical weeding in the alleyways can be useful in the early stages of development on the ground with a tendency to form crust and when you want to eliminate weeds at different times of the growing cycle. The weeding in the intermediate and final stages of the cycle, however, frequently damaging the already reduced and shallow root system, and sometimes are too risky for the integrity of the bulbs. With the weeding should avoid reporting the ground in the vicinity of the bulb, but rather to leave slightly the base of the plant, especially in humid years, so as to reduce the incidence of rots.
    The mechanical control of weeds is done with hoeing surface, performed with small tillers, not to cause damage to root, very shallow.
    Often weeding are integrated with the chemical weeding in post-emergence, with Oxyfluorfen or Setoxydim to the stage of 3-4 leaves.
    The weeding, as well as removing weeds, serve to reduce the loss of water by evaporation and then to keep the water reserves are very useful in the phase of enlargement of the bulbs, when you have the greatest demand for water.
    Therefore, under dry and low rainfall, especially during the spring, the weeding assume greater importance for which the chemical weed control, although less expensive than machining, it can not completely replace the need to reduce water losses. In the event that the company has availability irrigation can be performed in an emergency irrigation phase of enlargement of the bulb (April-May), especially in dry years.
    In May you manually delete the floral scapes when they reach an inch in length, to facilitate the enlargement of the bulbs, since the beginning of the production ceases vegetative activity. The elimination of floral scapes is also required for the packaging of garlic in braids, while for packaging nets seems that the presence of the flowering stem makes it easier to keep the garlic.
    Very important is the control of perennial weeds. Many perennial weeds have deep storage roots or rhizomes that resprout after the tops are cut or pulled (e.g., hedge bindweed, Canada thistle. etc.). Since the storage roots or rhizomes are too deep in the soil to damage with normal spading or rototilling, your best hope for organically controlling these weeds is to exhaust the storage organs by repeated removal of top growth. Generally, the net flow of nutrients is from the root until formation of the third or fourth leaf, so time your removals accordingly. Typically, eradication of deep-rooted perennials requires about 6-8 well-timed weedings the first year followed 3-5 the second.
    Integrated control of weeds garlic is summarized in Table 6.

    Table 6 - Summary information on the integrated control of weeds of the garlic cultivations.
    Time Weeds Active principle (a.p.) % di a.p. L/ha or Kg/ha

    Graminaceae and
    Gluphosinate ammonium

    Graminaceae and

    Winter Graminaceae and
    Annual Dicots

    Dicots Ioxynil 33,20 0,1-0,6

    Graminaceae Propaquizafop
    Quizalofop-ethyl isomer D

  • Glyphosate (N-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide used to kill weeds, especially annual broadleaf weeds and grasses known to compete with commercial crops grown around the globe. It was discovered to be a herbicide by Monsanto chemist John E. Franz in 1970.[3] Monsanto brought it to market in the 1970s under the trade name "Roundup", and Monsanto's last commercially relevant United States patent expired in 2000. Glyphosate was quickly adopted by farmers, even more so when Monsanto introduced glyphosate-resistant crops, enabling farmers to kill weeds without killing their crops. In 2007 glyphosate was the most used herbicide in the United States agricultural sector, with 180 to 185 million pounds (82,000 to 84,000 tonnes) applied, and the second most used in home and garden market where users applied 5 to 8 million pounds (2,300 to 3,600 tonnes); additionally industry, commerce and government applied 13 to 15 million pounds (5,900 to 6,800 tonnes). With its heavy use in agriculture, weed resistance to glyphosate is a growing problem. While glyphosate and formulations such as Roundup have been approved by regulatory bodies worldwide and are widely used, concerns about their effects on humans and the environment persist. Glyphosate's mode of action is to inhibit an enzyme involved in the synthesis of the aromatic amino acids tyrosine, tryptophan and phenylalanine. It is absorbed through foliage and translocated to growing points. Because of this mode of action, it is only effective on actively growing plants; it is not effective as a pre-emergence herbicide. Some crops have been genetically engineered to be resistant to glyphosate (i.e., "Roundup Ready", also created by Monsanto Company). Such crops allow farmers to use glyphosate as a post-emergence herbicide against both broadleaf and cereal weeds, but the development of similar resistance in some weed species is emerging as a costly problem. Soy was the first "Roundup Ready" crop.
    Glyphosate is an aminophosphonic analogue of the natural amino acid glycine, and the name is a contraction of gly(cine) phos(phon)ate. The molecule has several dissociable hydrogens, especially the first hydrogen of the phosphate group. The molecule tends to exist as a zwitterion where a phosphonic hydrogen dissociates and joins the amine group. Glyphosate is soluble in water to 12 g/L at room temperature. Main deactivation path is hydrolysis to aminomethylphosphonic acid (AMPA).
    Glyphosate kills plants by interfering with the synthesis of the aromatic amino acids phenylalanine, tyrosine and tryptophan. It does this by inhibiting the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), which catalyzes the reaction of shikimate-3-phosphate (S3P) and phosphoenolpyruvate to form 5-enolpyruvyl-shikimate-3-phosphate (ESP). ESP is subsequently dephosphorylated to chorismate, an essential precursor for the amino acids mentioned above. These amino acids are used in protein synthesis and to produce secondary metabolites such as folates, ubiquinones and naphthoquinone. X-ray crystallographic studies of glyphosate and EPSPS show that glyphosate functions by occupying the binding site of the phosphoenolpyruvate, mimicking an intermediate state of the ternary enzyme substrates complex. The commercially important enzyme that glyphosate inhibits, EPSPS, is found only in plants and micro-organisms. EPSPS is not present in animals, which instead obtain aromatic amino acids from their diet. However, glyphosate has also been shown to inhibit other plant enzymes, and also has been found to affect animal enzymes. Glyphosate is absorbed through foliage. Because of this mode of action, it is only effective on actively growing plants; it is not effective in preventing seeds from germinating.
    About environmetal problems, glyphosate adsorbs strongly to soil and is not expected to move vertically below the six inch soil layer; residues are expected to be immobile in soil. Glyphosate is readily degraded by soil microbes to AMPA and carbon dioxide. Glyphosate and AMPA are not likely to move to ground water due to their strong adsorptive characteristics. However, glyphosate does have the potential to contaminate surface waters due to its aquatic use patterns and through erosion, as it adsorbs to soil particles suspended in runoff. If glyphosate reached surface water, it would not be broken down readily by water or sunlight. The median half-life of glyphosate in soil ranges between 2 and 197 days; a typical field half-life of 47 days has been suggested. Soil and climate conditions affect glyphosate's persistence in soil. The median half-life of glyphosate in water varies from a few days to 91 days. According to the National Pesticide Information Center fact sheet, Glyphosate is not included in compounds tested for by the Food and Drug Administration's Pesticide Residue Monitoring Program, nor in the United States Department of Agriculture's Pesticide Data Program, however a field test showed that lettuce, carrots, and barley contained glyphosate residues up to one year after the soil was treated with 3.71 pounds of glyphosate per acre.
    Glyphosate is effective in killing a wide variety of plants, including grasses, broadleaf, and woody plants. It has a relatively small effect on some clover species.[21] By volume, it is one of the most widely used herbicides. It is commonly used for agriculture, horticulture, viticulture and silviculture purposes, as well as garden maintenance (including home use). Prior to harvest glyphosate is used for crop desiccation (siccation) to increase the harvest yield. In many cities, glyphosate is sprayed along the sidewalks and streets, as well as crevices in between pavement where weeds often grow. However, up to 24% of glyphosate applied to hard surfaces can be run off by water. Glyphosate contamination of surface water is highly attributed to urban Glyphosate is one of a number of herbicides used by the United States and Colombian governments to spray coca fields through Plan Colombia. Its effects on legal crops and effectiveness in fighting the war on drugs have been disputed. There are reports that widespread application of glyphosate in attempts to destroy coca crops in South America have resulted in the development of glyphosate-resistant strains of coca nicknamed "Boliviana Negra", which have been selectively bred to be both "Roundup Ready" and larger and higher yielding than the original strains of the plant.However, there are no reports of glyphosate-resistant coca in the peer-reviewed literature. In addition, since spraying of herbicides is not permitted in Colombian national parks, this has encouraged coca growers to move into park areas, cutting down the natural vegetation, and establishing coca plantations within park lands. Glyphosate is the active ingredient in herbicide formulations containing it. However, in addition to glyphosate salts, commercial formulations of glyphosate contain additives such as surfactants which vary in nature and concentration. Laboratory toxicology studies have suggested that other ingredients in combination with glyphosate may have greater toxicity than glyphosate alone. Toxicologists have studied glyphosate alone, additives alone, and formulations. Glyphosate has a United States Environmental Protection Agency (EPA) Toxicity Class of III (on a I to IV scale, where IV is least dangerous) for oral and inhalation exposure. Thus, as with other herbicides, the EPA requires that products containing glyphosate carry a label that warns against oral intake, mandates the use of protective clothing, and instructs users not to re-enter treated fields for at least 4 hours. Glyphosate does not bioaccumulate in animals; it is excreted in urine and faeces. It breaks down variably quickly depending on the particular environment. Human acute toxicity is dose related. Acute fatal toxicity has been reported in deliberate overdose. Epidemiological studies have not found associations between long term low level exposure to glyphosate and any disease. The EPA considers glyphosate to be noncarcinogenic and relatively low in dermal and oral acute toxicity. The EPA considered a "worst case" dietary risk model of an individual eating a lifetime of food derived entirely from glyphosate-sprayed fields with residues at their maximum levels. This model indicated that no adverse health effects would be expected under such conditions. Glyphosate is present in human urine samples from 18 European countries. Malta showed the highest test results with the chemical showing up in 90% of samples and the average for all countries was 43.9%. Diet was stated as the main source. The European Commission's review of the data conducted in 2002 concluded that there was equivocal evidence of a relationship between glyphosate exposure during pregnancy and cardiovascular malformations; however, a review published in 2013 found that the evidence "fails to support a potential risk for increased cardiovascular defects as a result of glyphosate exposure during pregnancy Health, environmental and food chain effects from alteration of gut flora by wide use of glyphosate are largely unexplored.
  • Glufosinate or its ammonium salt DL-phosphinothricin is an active ingredient in several nonselective systemic herbicides such as Basta, Rely, Finale, Ignite, Challenge, and Liberty. It interferes with the biosynthetic pathway of the amino acid glutamine and with ammonia detoxification. It has been used in pre-harvest crop desiccation. Some plants have been genetically modified for resistance to glufosinate. The gene which gives resistance to glufosinate is a bar or pat gene which was first isolated from two species of Streptomyces bacteria. There are glufosinate-resistant transgenic varieties of several crops, including cotton, canola, corn, soybean, sugarbeet, and rice. Of these, canola, cotton, soybean and maize are currently on the market. This includes Bayer's LibertyLink genes, used in over 100 hybrids. Glufosinate was found to be toxic to reproduction and was included in a biocide ban proposed by the Swedish Chemicals Agency and approved by the European Parliament on January 13, 2009.Phosphinothricin is an glutamine synthetase inhibitor that binds to the glutamate site. Glufosinate-treated plants die due to a buildup of ammonia and corresponding decrease in pH in the thylakoid lumen, leading to the uncoupling of photophosphorylation. The uncoupling of photophosphorylation causes the production of reactive oxygen species, lipid peroxidation, and membrane destruction.
  • Pendimethalin protects crops like wheat, corn, soybeans potatoes, cabbage, peas, carrots and asparagus. It is used to control annual grasses and certain broadleaf weeds which interfere with growth, development, yield and quality of agricultural and horticultural crops by competing on nutrients, water and light. In areas where weed infestation is particularly high, yield losses can render wheat production economically unviable. In addition to wheat, a large number of crops are grown in Europe that are a relatively small percentage of total agricultural output. Herbicide options are limited for these minor crops, with few effective herbicides available in the vegetable sector. Long-term field studies performed in Germany by governmental research and advisory institutes together with farmers rank Pendimethalin as an efficient herbicide to control blackgrass, regarding to weed control efficacy, crop yield, treatment costs and environmental impact. Pendimethalin acts both pre-emergence, that is before weed seedlings have emerged, and early post-emergence. Pendimethalin inhibits root and shoot growth. It controls the weed population and prevents weeds from emerging, particularly during the crucial development phase of the crop. Its primary mode of action is to prevent plant cell division and elongation in susceptible species. In the HRAC classification of herbicides according their mode of action, pendimethalin is listed in group K1. Herbicide resistance typically increases production costs and limits options for herbicide selection, cultivations and rotations. Up to now Pendimethalin does not show resistance. It is not cross-resistant with other grass weed herbicides. This means that Pendimethalin supports the effects of other supplementary grass weed herbicides that use a different mode of action. Pendimethalin is registered globally for a wide range of crops, according to human and environmental safety standards by the European Commission, US-EPA, Canada-PMRA, Japan, Brazil-ANVISA and others.
  • Metazachlor is a residual herbicide used to control broad leaved weeds and annual grasses. It is a synthetic compound and a member of the chloroacetamide chemical family. It was first manufactured by BASF as an herbicide and is now commonly used on its own and in combination with other plant protection products, such as clomazone and quinmerac. Metazachlor is applied directly to the soil and is not suitable as an aerial spray. It can be applied to all soil types expect sand, very light soils and soils containing more than 10% organic material. The compound is absorbed through the roots of the target weeds to the growing points of the plant. Here it inhibits VLCFAs, thereby inhibiting cell division. Metazachlor can be applied to sown oilseed rape, vegetable crops such as brassicas, like Brussels sprouts, cauliflowers, cabbage, broccoli and calabrese as well turnips and Swedes. It can also be used on ornamentals, nursery stock, in forestry and on wood land.
  • Oxyfluorfen is a member of the diphenyl ether group of herbicides. 4Farmers Oxyfluorfen 240 EC Herbicide has the inhibitor of protoporphyrinogen oxidase mode of action. For weed resistance management Oxyfluorfen 240 EC Herbicide is a Group G herbicide. Some naturally occurring weed biotypes resistant to Oxyfluorfen may exist through normal genetic variability in any weed population. The resistant individuals can eventually dominate the weed population if these herbicides are used repeatedly. These resistant weeds will not be controlled by Oxyfluorfen. Since the occurrence of resistant weeds is difficult to detect prior to use, 4Farmers Pty Limited accepts no liability for any losses that may result from the failure of Oxyfluorfen to control resistant weeds. For optimum residual weed control, Oxyfluorfen should be applied to the soil surface prior to weed emergence after all other agricultural operations have been completed, such as mechanical cultivation and reshaping of irrigation furrows. The area should be left undisturbed during the period of desired weed control. When applied to seedling weeds, they should be young and actively growing. Weed control for up to 6 months is expected but spot treatment, with knockdown herbicides, for escape weeds and perennial grassemay be necessary.Spray equipment should be calibrated before use. Oxyfluorfen should be applied uniformly as a directed treatment to the base of tree and vine crops using flat fan or off-centre nozzles. Complete coverage of seedling weeds is required for maximum knockdown effect. A water volume of 250 to 500 litres per hectare is recommended for treatments of bare soil. A spray volume of 100 to 1,350 litres per hectare is recommended where seedling weeds (4 to 6 leaf) are present. Ensure both the weed foliage and the soil surface are sprayed. Use higher volumes for high weed density. Tank mixtures of 75mL/ha of Oxyfluorfen with Glyphosate 450 or Glyphosate 360 herbicides should be applied in 30 to 200 litresspray volume per hectare. For maximum residual control Oxyfluorfen should not be incorporated or disturbed after application.
  • Ioxynil: main names are Totril, Preskil . It is efficient against broad leaf weeds at rates of about 500 g.a.i/ha. However, it may be marginally selective and may be used in repeated applications at lower rates, such as 100 to 200 g a.i./ha. Mixtures of bromoxynil and ioxynil exist on the market (Oxytril) : extreme care should be taken in using these mixtures. Use rates that will bring a maximum of 100 g.a.i. bromoxynil per ha in repeated applications (2 or 3 applications with one week interval).
  • Quizalofop-ethyl isomer D : known as Targa D, Pilot or Assure, it is efficient against grasses at rates between 60 g.a.i/ha (annuals) and 150 g.a.i/ha(perennials). It should be applied after 3 leaves until tillage (grasses). The addition of oil or surfactant is highly recommended (type Agral).
  • Propaquizafop is a synthetic compound of the chemical family the aryloxyphenoxypropionate. Propaquizafop acts as a systemic herbicide of annual and perennial grasses. It is applied as a foliar spray and, being quickly absorbed through the leaves and translocated to the meristematic growing regions of the plants, where it inhibits cell growth and division through the inhibition of ACCase inhibition. Propaquizafop can be used on a wide range of broad-leaved crops, including sugarbeet, oilseed rape, soybeans, sunflower, other field crops, vegetables, fruit trees, vineyards and forestry.
  • It is important to note that a non chemical control is possible at Pre-emergence weed control. We recommend the use of machines which perfectly controls the working depth and performs a shallow cultivation that will avoid bringing deep weeds into the top soil layer. It will also facilitate an even weed emergence. When soil preparation is necessary, we try to work the soil as shallow as possible. Because of an excellent working depth control it can finetune the soil preparation, incorporate the residues in the top soil layer or make the right finish. It will also avoid bringing deep weeds in the top layer (essential for non-competitive crops such as onion, garlic) and facilitate an even weed emergence (easier to destroy). It may be fitted either with disks placed up front or ripper tines with the levelling cross board system. When a large amount of crop residues has to be handled, a front straw harrow may be fitted in front of the discs. In some cases we might recommend the use of a shallow cultivation tool in combination with the seeder automatic machines.
    Pulling weeds is a last resort when other methods of management have failed, or when a few escapes need to be removed to prevent seed production. For some small seeded, slow establishing crops like carrots or parsnips that do not transplant well, hand pulling is sometimes necessary to remove small weeds from around the young crop. In the latter case, the amount of hand weeding can be reduced by sowing slow emerging crops in relatively weed free areas of the garden and preceding planting with a short period of clean fallow to reduce weed density.
    The best technique for pulling weeds depends on the type of weed and the situation. Small weeds are easiest to pull when the soil is wet (i.e., too wet for tillage). Keeping your weight off of the soil at such times is critical, however, to avoid destroying soil structure (Stay of soil). To pull small weeds from among small, fragile crop plants like young carrots, place a finger on the ground on both sides of the weed and pull with the other hand. This holds the soil in place, and prevents uprooting the crop along with the weed.
    Species with strong taproots are also easiest to pull when the soil is wet, but again, care should be taken to avoid trampling the soil. Also, the crop should be dry to avoid spreading disease. Grasp the weed by the top of the taproot rather than by the stem or foliage. Then slowly pull straight up with a slight twisting motion. This will break the feeder roots free from the taproot and allow the taproot to be pulled up whole. A jerking pull will tend to break the root. Removing most of the root is critical since the plant will resprout from dormant buds in any large pieces that remain in the soil. The resulting complex root system will be impossible to pull and you will have to dig to remove it. Maintaining a high state of tilth is critical for hand pulling weeds with taproots (Tilth & weeding). If the soil is moist, loose and has a good crumb structure, even large dandelions can be pulled whole. If the soil is not in good condition or is not wet enough or the weed is really large, an asparagus knife, long trowel or narrow spading fork may be needed to get the whole root. If the plant is so large that you have to hand pull it, it may reroot if the soil is moist or rain is expected. Also, if the plant is flowering, it may make seeds even after you uproot it. Consequently, carrying along a couple of 5 gallon buckets to use for removing the weeds from the garden may help reduce subsequent weeding. Weeds that are unlikely to set seeds can be left on a hard surface like concrete or boards until thoroughly dead and then composted.
    Fibrous rooted species like annual grasses and plantains are easiest to pull when the soil is starting to dry. If the soil is dry and hard, the shoot will tend to break off, leaving the root system to resprout, whereas if the soil is moist, a lot of soil will cling to the roots. If the soil is moderately dry, hitting the root crown against any hard object will knock most of the soil off the roots. This will decrease likelihood of the weed rerooting if it is left on the ground and avoid exporting your precious topsoil if it is removed from the garden.
    If a few weeds with spreading rhizomes or root systems are encroaching from the edge of the garden, pulling the shoots is more effective than hoeing. Hoeing cuts the shoots near the surface whereas pulling the shoot usually brings up a long white underground shoot. This depletes the underground root-rhizome system more quickly than hoeing. Canada thistle is one such species. Since the base and underground portion of the shoot is free of thorns, the plant can be pulled from this point without heavy gloves.

    Harvesting of the garlic
    Physiological maturity is manifested by the presence of yellow leaves and dried. Garlic is generally ready for harvest when the leaves are yellow or dried in their upper third and start to bend on the ground. If the harvest get too early tunics are bad dried, while if the harvest is delaied the bulbs are often invaded by saprophytic organisms that confer them a blackish colour.
    The harvest for fresh starts from April to May, while that for the product for storage in plaits or grappes from June (Southern Italy) to August (Northern Italy) . If the garlic is prematurely harvested the product destinated to storage is undergoes to rapid dehydration.
    The harvest is commonly done by machine. But especially in southern Italy, the machines are not much used and this for the farm pulverization and because the farm sizes are too small and for the individualistic causes of the farmers and for different needs related to the type of business and the marketing methods.
    They are available the facilitator machines and the integral harvester machines.

    Facilitator machines for the garlic harvest
    They are divided into two main groups: Integral harvesting machines
    They are dig-harvesing-tying single row, trained by tractor. The harvesting head (lateral or rear) is constituted of a excavation plowshare, a shaking device for the separation of soil from plants and by a device that holds the plants for the leaf apparatus. The plants are then accompanied to a device binder that binds the plants in bundles of 30-40 plants and their deposition on the ground. These machines operate on a single row and have a working capacity very limited (from 0.9 up to 0.12 ha/hour) but completely eliminate the subsequent phases of cleaning and packaging. The harvesting, cleaning of decks, loading and transportation account for about 40 hour-man/ha.
    In our campaigns, drying, cleaning and packaging of garlic from storage are traditionally carried out in the field for which the use of harvesting grains seems primarily intended for garlic for fresh consumption. The average production of garlic are of the order of 10-12 t/ha in a white bulb types and 7-8 t/ha in the red ones. The production of tip frequently reach 20 t/ha.
    Follow the exposure of some machines used for the harvest of the garlic (figures 17, 18, 19 and 20):

    Figure 17 - 1-row garlic harvester-binder. Lifting is done by a blade which passes under the garlic bulbs and by two belts which pull up the garlic by the leaves. The garlic is carried by the belts, passing through a vibrator, to an automatic bundle binding system. The bundles of garlic are then removed by a conveyor belt. The machine is operated by one person. Lateral movement is ensured hydraulically. The machine has setting systems allowing it to be adapted to various types of planting. Sideways movement of the machine to align it on the row to be harvested, share depth, height of the lifting belts, binding height, string tension, bundle size adjustment.
    The characteristics are: 1-row per machine; carried by 1 person; distance between rows: 40 cm minimum; nominal speed: 4 km/h; tractor power: 50 hp; sideways movement between rows: 130 cm.
    The technique characteristics are: a mass of 800 kg; the length of 3.400 mm; the wide 2.100 mm; height 1.600 mm.

    Figure 18 - 2-row garlic harvester-binder. Similar to the previous described. The machine is carried by two people. The operating characteristics are: machine 2 rows; minimum distance between rows 43 cm; maximum distance between rows 55 cm; speed 4 km/h; tractor power 70 hp; lateral displacement between rows: 130 cm; mass 1,430 kg; length 3,400 mm, width 2,000 mm, height 2,000 mm.

    Figure 19 - Harvester sharp. Similar to the previous described. The machine is run by two people. The main operating characteristics are: machine 2 rows; minimum distance between rows 43 cm; maximum distance between rows 55 cm; speed 4 km/h; tractor power 70 hp; lateral displacement between rows 70 cm; mass 1,280 kg; length 4,100 mm, width 2,750-3,500 mm, height 2,450 mm.

    Figure 20 - 3 or 4 or 5 row garlic harvester-topper SAC.wmv. Double chassis, towed machine. It is hydraulically powered by pumps which are driven by the tractor's power take-off. The lifting system is identical and independent for each row. The bulb is lifted by a blade and the leaves are grabbed between two belts. The garlic is carried to the topping system after passing through a vibrator. A second set of belts levels off all the bulbs and two disks cut the leaves. A conveyor belt carries the bulbs to one side of the machine. After being cut, the leaves fall on to the ground behind the machine. The machine is operated by one person, and it has setting systems allowing it to be adapted to various types of planting. Lateral guidance is hydraulically controlled. technical characteristics: 3-, 4- or 5-row machine; minimum setting between rows 43 cm; maximum setting between rows 50 cm; nominal speed 3 km/h; tractor power 70 hp; lateral displacement between rows 70 cm; mass 2,400, 2,800, and 3,400 kg; length (fixed) 4,700 mm; width 2,000, 2,200, and 3,500 mm, depending from row number (3,4 or 5 rows); height (fixed) 2,300 mm.

    After being extirpated the garlc must undergo a natural drying that can occur in the open field or farmyard. The finished product must be marketed between July 30 and 31 May of the following year. The drying can also be forced, when air produced by a fan is forced through a grid, some times even heated (depending on air humidity), or through dedicated boxes with grids where fresh garlic was placed.

    Chemical composition
    Garlic has a high energy value (140 cal per 100 g of the edible part) and a high content of potassium, iodine, zinc, manganese, vitamin B.
    The dry matter content of garlic is generally high and can vary, according to the cultivar from 30 to 56%.
    The bulb is almost devoid of starch, but it accumulates carbohydrates, under form of fructans (long-chain polymer of fructose).
    A protein content of 4-6% is commonly low according with the high content of dry matter, while it is very low in fat even if it contains, an essential oil rich in sulphur compounds (0.1-0.25%). The characteristic odour and flavour are conferred by some volatile sulphur compounds (mainly allicin) that are formed from some precursor odourless and non-volatile (alliin) of the bulb when the plant tissues are damaged (cut, crushed).
    Allicin features the thiosulphinate functional group, R-S(O)-S-R. The compound is not present in garlic unless tissue damage occurs, and is formed by the action of the enzyme alliinase on alliin. Allicin is chiral but occurs naturally only as a racemate. The racemic form can also be generated by oxidation of diallyl disulphide:


    Alliinase is irreversibly deactivated below pH 3; as such, allicin is generally not produced in the body from the consumption of fresh or powdered garlic. Furthermore, allicin can be unstable, breaking down within 16 h at 23 C.
    Several animal studies published between 1995 and 2005 indicate that allicin may reduce atherosclerosis and fat deposition, normalize the lipoprotein balance, decrease blood pressure,[11][12] have anti-thrombotic and anti-inflammatory activities, and function as an antioxidant to some extent. Other animal studies have shown a strong oxidative effect in the gut that can damage intestinal cells, though many of these results were obtained by excessive amounts of allicin, which has been clearly shown to have some toxicity at high amounts, or by physically injecting the lumen itself with allicin, which may not be indicative of what would happen via oral ingestion of allicin or garlic supplements. A randomized clinical trial funded by the National Institutes of Health (NIH) in the United States and published in the Archives of Internal Medicine in 2007 found that the consumption of garlic in any form did not reduce blood cholesterol levels in patients with moderately high baseline cholesterol levels. The fresh garlic used in this study contained substantial levels of allicin, so the study casts doubt on the ability of allicin when taken orally to reduce blood cholesterol levels in human subjects.
    In 2009, Vaidya, Ingold and Pratt clarified the mechanism of the antioxidant activity of garlic, such as trapping damaging free radicals. When allicin decomposes, it forms 2-propenesulfenic acid, and this compound is what binds to the free-radicals. The 2-propenesulfenic formed when garlic is cut or crushed has a lifetime of less than one second.
    Allicin has been found to have numerous antimicrobial properties, and has been studied in relation to both its effects and its biochemical interactions. One potential application is in the treatment of methicillin-resistant Staphylococcus aureus (MRSA), an increasingly prevalent concern in hospitals. A screening of allicin against 30 strains of MRSA found high level of antimicrobial activity, including against strains that are resistant to other chemical agents. Of the strains tested, 88% had minimum inhibitory concentrations for allicin liquids of 16 mg/L, and all strains were inhibited at 32 mg/L. Furthermore, 88% of clinical isolates had minimum bactericidal concentrations of 128 mg/L, and all were killed at 256 mg/L. Of these strains, 82% showed intermediate or full resistance to mupirocin. This same study examined use of an aqueous cream of allicin, and found it somewhat less effective than allicin liquid. At 500 mg/L, however, the cream was still active against all the organisms tested—which compares well with the 20 g/L mupirocin currently used for topical application.
    A water-based formulation of purified allicin was found to be more chemically stable than other preparations of garlic extracts. They proposed that the stability may be due to the hydrogen bonding of water to the reactive oxygen atom in allicin and also to the absence of other components in crushed garlic that destabilize the molecule.
    Although there are preliminary studies indicating some potential benefit of garlic in treating the common cold, a 2012 report in the Cochrane Database of Systematic Reviews concluded that "there is insufficient clinical trial evidence regarding the effects of garlic in preventing or treating the common cold. A single trial - The trial that relied on self reported episodes of the common cold but was of reasonable quality in terms of randomisation and allocation concealment, suggested that garlic may prevent occurrences of the common cold but more studies are needed to validate this finding. Claims of effectiveness appear to rely largely on poor-quality evidence". Similar conclusions are voiced in a 2013 report, which states "Garlic as a preventative or treatment option for the common cold" and still "could not be recommended, as only one relatively small trial evaluated the effects separately. Garlic might be effective in some areas of clinical practice, but the evidence levels were low, so further researches should be well designed using rigorous method to avoid potential biases".
    Alliin is a sulfoxide that is a natural constituent of fresh garlic. The formula is (IUPAC name) (2R)-2-amino-3-[(S)-prop-2-enylsulfinyl]propanoic acid. It is a derivative of the sulphurate amino acid named cysteine. When fresh garlic is chopped or crushed, the enzyme alliinase converts alliin into allicin, which is responsible for the aroma of fresh garlic. Garlic has been used since antiquity as a therapeutic remedy for certain conditions now associated with oxygen toxicity, and, when this was investigated, garlic did indeed show strong antioxidant and hydroxyl radical-scavenging properties, it is presumed owing to the alliin contained within.
    Alliin has been found to affect immune responses in blood.
    Alliin was the first natural product found to have both carbon- and sulfur-centered stereochemistry.
    The composition and the energy value of garlic is given in Table 7

    Table 7 – Composition and energy value of 100 g of fresh bulb.

    Substance Value Substance Value Substance Value
    Edible part
    Carbohydrates available
    Dietary fiber
    75,0 %
    80,0 g
    6,4 g
    0,6 g
    8,4 g
    2,1 g
    141 kcal
    17,0 mg
    401,0 mg
    1,5 mg
    181,3 mg
    153,2 mg
    1,2 mg
    14,2 µg
    Niacin (vit. B3)
    Vitamina C
    Thiamine (vit. B1)
    Riboflavin (vit. B2)
    Pantothenic acid (vit. B5)
    Pyridoxine (Vit. B6)
    Folate (vit. B9)
    0,7 mg
    31,2 mg
    0,2 mg
    0,1 mg
    0,6 mg
    1,2 mg
    3,0 µg

    By analyzing the biomolecular composition of garlic, it has been observed that garlic displays a plethora of biological effects including immunomodulation. Although some immunomodulatory proteins from garlic have been described, their identities are still unknown. The present study was envisaged to isolate immunomodulatory proteins from raw garlic, and examine their effects on certain cells of the immune system (lymphocytes, mast cells, and basophils) in relation to mitogenicity and hypersensitivity. Three protein components of approximately 13 kD (QR-1, QR-2, and QR-3 in the ratio 7:28:1) were separated by Q-Sepharose chromatography of 30 kD ultrafiltrate of raw garlic extract. All the 3 proteins exhibited mitogenic activity towards human peripheral blood lymphocytes, murine splenocytes and thymocytes. The mitogenicity of QR-2 was the highest among the three immunomodulatory proteins. QR-1 and QR-2 displayed hemagglutination and mannose-binding activities; QR-3 showed only mannose-binding activity. Immunoreactivity of rabbit anti-QR-1 and anti-QR-2 polyclonal antisera showed specificity for their respective antigens as well as mutual cross-reactivity; QR-3 was better recognized by anti-QR-2 (82%) than by anti-QR-1 (55%). QR-2 induced a 2-fold higher histamine release in vitro from leukocytes of atopic subjects compared to that of non-atopic subjects. In all functional studies, QR-2 was more potent compared to QR-1. Taken together, all these results indicate that the two major proteins QR-2 and QR-1 present in a ratio of 4:1 in raw garlic contribute to garlic's immunomodulatory activity, and their characteristics are markedly similar to the abundant Allium sativum agglutinins (ASA) I and II, respectively.
    It is recently demonstrated that the immunomodulatory proteins present in garlic are identical to the garlic lectins ASA I and ASA II (Clement F, Pramod SN, Venkatesh YP. Int. Immunopharmacol. 2010; 10: 316-324). In this study, the stability of garlic lectins as a function of pH, temperature and denaturants has been examined in relation to biological activity (hemagglutination and phagocytosis). Stability of garlic lectins in simulated gastric fluid (SGF) was assessed by their hemagglutination activity, immunoreactivity, and intactness by SDS-PAGE. Garlic lectins were moderately stable in SGF for up to 30 min; while they retained hemagglutination activities, immunoreactivity with the respective rabbit antiserum decreased immediately (0.5 min) to 10-30%. ASA I retained ~80% hemagglutination activity in the pH range 2-12; however, ASA II retained only 40% in the pH ranges 2-4 and 10-12. Garlic lectins exposed to 60 C (30 min) and pepsin (1 and 2 min) retained hemagglutination and phagocytic activities. Urea (4M) and Gdn.HCl (2M) did not affect hemagglutination. The immunogenicity of garlic lectins upon oral feeding in BALB/c mice was examined. A lectin-specific serum IgG response was seen in mice comparable to the oral immunogen, phytohemagglutinin. The recovered lectin in feces of mice administered with garlic lectins showed antigenicity identical to that of the administered proteins. The stabilities of the garlic lectins, their ability to withstand the gastrointestinal passage, and their recognition by the immune system upon oral feeding reinforce the reported presence of natural antibodies to garlic proteins in normal human sera.
    Further observations on the biomolecular composition of the garlic induces us to consider some studies that demonstrate the possible use of substances constituting the garlic in various fields. In particular, the lectins of the garlic are promising candidate molecules for crop protection against pest insects that have an mug chewer apparatus (Lepidoptera larvae) or an mug apparatus stinging and sucking such as aphid and many other Homoptera.
    Molecular mechanism of toxicity and interaction of lectins with midgut receptor proteins has been described in many reports. Lectins show its effect right from sensory receptors of mouth parts by disrupting the membrane integrity and food detection ability. Subsequently, enter into the gut lumen and interact with midgut glycosylated proteins like alkaline phosphatase (ALP), aminopeptidase-N (APN), cadherin-like proteins, polycalins, sucrase, symbionin and others. These proteins play critical role in life cycle of insect directly or indirectly. Lectins interfere with the activity of these proteins and causes physiological disorders leading to the death of insects. Lectins further transported across the insect gut, accumulated in various body parts (like haemolymph and ovary) and interact with intracellular proteins like symbionin and cytochrome p450. Binding with cytochrome p450 (which involve in ecdysone synthesis) might interfere in the development of insects, which results in growth retardation and pre-mature deat

    Adversities of the garlic

    Diseases of the garlic


  • Garlic rust
  • :

    Causal agents: Puccinia allii Rudolph, 1829; Puccinia Pers., 1801 spp.

    - Taxonomy of Puccinia allii
    Nature: Natura, C. Linnaeus, 1758
    Physical world: Mundus, Plinius
    Natural bodies: Naturalia, Plinius
    Natural bodies: Biota
    Domain: Eukaryota, Whittaker & Margulis,1978
    Kingdom: Fungi, T.L. Jahn & F.F. Jahn, 1949 ex R.T. Moore, 1980 - Fungi
    Subkingdom: Dikarya, D.S. Hibbett et al., in D.S. Hibbett et al., 2007
    Phylum: Basidiomycota, H.C. Bold, 1957 ex R.T. Moore, 1980 – Basidiomycetes
    Subphylum: Pucciniomycotina, R. Bauer et al., 2006
    Class: Urediniomycetes, R. Bauer et al., 2006
    Order: Uredinales, Clem. & Shear, 1931
    Family: Pucciniaceae
    Genus: Puccinia Pers., 1801
    Specific descriptor: allii(DC.) F. Rudolph, 1829
    Scientific name: Puccinia allii F. Rudolph, 1829
    Synonyms: Puccinia blasdalei Dietel & Holw. 1893; Puccinia mixta Fuckel 1870; Puccinia porri (Sowerby) G. Winter 1882; Uredo ambigua Dc. 1815; Uredo porri Sowerby 1810; Uromyces ambiguus (Dc.) Lv. 1847; Uromyces durus Dietel 1907.

    - Symptomatology, identification and control of the disease
    In Italy, generally, garlic rust is not considered an economic problem. In some case, in relation to climatic conditions we can observe a severe infection of the disease caused an average 51% reduction in yield throughout the state.
    The rust pathogen is comprised of genetically distinct sub-groups which differ in different parts of the world. Most attacks occur from mid-summer until late autumn. The symptoms interest the leaves. Bright orange pustules on both sides of infected leaves. These are initially enclosed by the surface tissues of the leaf, but break open to release dusty, orange, airborne spores Severe attacks may cause leaves to shrivel prematurely and will reduce vigour.
    Infection is worse on nitrogen-rich soils with low potassium, so take care with fertiliser applications. Do not crowd plants, as this raises humidity and increases the likelihood of infection. Dispose of all plant debris at the end of cropping.
    Suppliers sometimes claim a degree of resistance for certain varieties, check the latest catalogues for those currently available.
    The rust fungi are described as biotrophs; that is, they grow within the living tissues of the plant and extract nutrients from the cells without killing them. However, although they do not kill tissues, heavy attacks by rusts can cause the leaves to shrivel and die prematurely and can depress vigour.
    Garlic rust and all the rusts are not able to survive on dead plant material, so must either alternate with a different, perennial host, or produce resting spores to pass the dormant season.
    The garlic rust pathogen seems to fulfil its entire life cycle on garlics, without the need for an alternate host. On some other Allium species the fungus begins to produce dark resting spores within the orange pustules as the foliage dies down . These resting spores have been observed occasionally on garlic, but the role that they play in the disease on this crop is currently unknown. It is likely that there are simply sufficient garlic in the ground at all times of the year to ensure continuity of infection, without the need for resting spores.
    Puccinia allii has been confirmed as being seed-borne, but this is not currently thought to be of any great significance in the spread of the disease.
    It is thought that a number of strains of Puccinia allii exist, varying in their ability to infect different Allium species.
    Research carried out demonstrated that the weight of harvested bulbs is 25% to 60% smaller than the average weight in the previous year, and soluble solids were reduced by an average of 15%. Until recently, garlic varieties that are resistant or highly tolerant to rust have not been grown in garlic production fields. Open pollinated progenies derived from 3 Plant Introduction (PI) accessions of the U.S. Dept. of Agriculture-Agricultural Research Service germplasm collection were inoculated with a suspension of urediniospores (1, 2 105/mL) isolated from rust infected garlic leaves obtained from production fields. Inoculations were carried out in a replicated experiment in the field under plastic covers, where 12 hours of misting was applied. The disease symptoms were scored on all leaves of the inoculated plants. The size of observed lesions varied from <1 to 280 mm2. Of the 118 plants evaluated, 9.3% had an average leaf area with rust symptoms of less than 1%. The majority of the plants (83.1%) had 1 to 5% of leaf area infected, and over 6% of plants had symptoms on 5 to 25% of their leaf surface. The highest number of plants with a low percent of rust symptoms on leaves was observed on progenies produced from PI 493099. While all maternal plants used to produce the seeds showed rust symptoms, the presence of progenies with ≤0.5% of leaf area infected indicated that a tolerance source to Puccinia allii may exist in the Allium sativum NPGS, germplasm collection.

    - Prevention and treatments
    Agronomic interventions: Chemical measures:

  • Downy Mildew of the garlic:
  • Causal agent: Peronospora destructor (Berk.) Casp. ex Berk., 1860

    - Taxonomy of Peronospora destructor (Berk.) Casp. ex Berk., 1860
    Nature: Natura, C. Linnaeus, 1758
    Physical world: Mundus, Plinius
    Natural bodies: Naturalia, Plinius
    Natural bodies: Biota
    Domain: Eukaryota, Whittaker & Margulis,1978
    Kingdom: Fungi, T.L. Jahn & F.F. Jahn, 1949 ex R.T. Moore, 1980 - Fungi
    Subkingdom: Dikarya, D.S. Hibbett et al., in D.S. Hibbett et al., 2007
    Phylum: Oomycota, Winter, 1897
    Subphylum: Peronosporomycotina, Winter, 1897
    Class: Peronosporomycetes, Dick, 2001
    Subclass: Peronosporomycetidae, Dick et al., 1984
    Order: Peronosporales, Clem. & Shear, 1931
    Family: Peronosporaceae
    Genus: Peronospora
    Specific descriptor: destructor (Berk.) Casp. ex Berk.
    Scientific name: Peronospora destructor (Berk.) Casp. ex Berk., 1860
    Synonyms: Peronospora destructor (Berk.) Casp. ex Berk., Botrytis destructor Berk., 1841, Peronospora schleideni Unger, 1847

    - Symptomatology, identification and control of the disease
    Downy mildew is a fungal disease affecting garlic’s and related species, including weedy species. Leaves initially develop pale, elongate patches. The spots may be water-soaked at first, and then later appear somewhat purplish. The spots become covered with a downy, greyish or white fungal growth. Affected leaves often die back. Bulbs of affected plants are smaller than normal and of poor quality. Infected bulbs may become shrivelled and discoloured in storage, or may sprout prematurely. Cool, damp weather favours spread of the disease.
    Downy mildew can develop from an initial infection by airborne spores into an epidemic very quickly if humidity and temperature conditions (1.5 to 7 hours of leaf wetness and 6 C to 27 C) are favourable. Spores can travel long distances in moist air, but are quickly killed by dry conditions. Initial sources of disease can be infected bulbs, sets, seeds, and plant debris.
    The downy mildew pathogen can survive for many years in the soil as oospores. In order to spread and infect plants, they need to have moist conditions. One spore stage of the pathogen is motile (it can swim) so free water is necessary for infection and spread. Additionally, spores may also be spread under windy rainy conditions
    Sporangiophores first appeared as outgrowths from stomata on abaxial leaflet surfaces 4-6 h after infected, glass-house-grown plants were exposed to high humidity, at temperature range of 4-25 C. Sporangiophores continued to develop over the next 6 h, first as simple elongating hyphae, then branching from a single axis (monopodially) to produce multiple, terminal sporangia (that measure 40-72 x 18-29 μm), which developed synchronously and polyblastically on each sporangiophore. Sporangia had smooth surfaces during development, were finely echinulate when mature, and were delimited by septa at the ends of terminal sporangiophore branches. Gametangia (oogonia and antheridia) developed extensively on inner surfaces of field-grown garlic leaves from smooth, bulbous hyphae adhering to the host epidermis. Each oogonium was surrounded by several antheridia. Oospores within leaf tissue of field-grown plants were enclosed by oogonial membranes. Each oospore had a heavily reticulate outer wall enclosing cytoplasm and liquid, possibly lipid. Cryofixation and low temperature scanning electron microscopy have provided new insights into the morphology of reproduction in garlic.

    - Prevention and treatments
    Agronomic interventions or Cultural Control: Chemical measures:
    spray at the first sign of disease; fungicides may be applied on a 7-day schedule, if necessary. For all fungicides, thorough coverage of foliage is important in the control of downy mildew. Below is a list of fungicides to be administered only in case of absolute necessity. It must be remembered that the shape and the presence of waxy substances on leaves Liliaceae make difficult the application of fungicides that tend to slip away before having explicate effective action. It is therefore must be careful to the formulation of crop protection and in particular the presence of wetting and other additives. To prevent the emergence of resistance phenomena is also recommended to alternate the active ingredients used.

    Forecasting Models:
    The first approach to warning systems consisted of the definition of periods favourable for the disease in Bulgaria (Vitanov, 1971). A similar approach was followed by Palti et al. (1972) who tried to define mildew-free periods analysing 10-year records of weather conditions in relation to the dates of onion mildew outbreak in Israel.
    In 1975, a bioclimatological model, based on microclimatic conditions, was developed in the Netherlands to define potential infection dates (Weille, 1975). In the following year, Stenina (1976) tried to forecast the disease in the Krasnodar region (Russia) using weather data.
    The first model based on disease cycle was developed by Jesperson and Sutton (1987) in Canada and called DOWNCAST. It defines whether primary infections are, or are not, possible on the basis of the meteorological conditions which are necessary for sporulation, infection and spore survival. A more detailed approach was followed by Battilani et al. (1996). They applied systems analysis to the onion-downy mildew pathosystem and they obtained ONIMIL, a model able to determine, for each day, the probability of establishing an infection caused by Peronospora destructor and its infection level, compared with the maximum. For practical use, it gives a forecasting of primary infection 7-14 days before its real appearance. Further studies improved the model, pointing out that plants are only sensitive from growth stage F (senescence of the first leaf, appearance of fifth - seventh leaf) (De Visser, 1990). Presence of the inoculum near the field is always necessary for the establishment of infection on seeded onion fields (Battilani et al., 1998).

    Basal Rot and White Rot:

    Causal agent: Fusarium spp. Link, 1809; Helmintosporium spp., Link ex Fries, 1821; Sclerotium cepivorum, Berk (Coley & Smith, 1987); Penicillium spp., Link, 1809.

    - Symptomatology, identification and control of the diseases
    The symptoms of basal rot are slow to develop. Often, they are seen as a yellowing and eventual dieback of the leaves. Sometimes one can also see white fungal growth at the bulb base, which will lead to both pre and post-harvest rotting. Postharvest rotting can include single, several or all of the cloves in the garlic bulb.
    The symptoms of white rot may look almost identical to basal rot, with the exception that the process of disease initiation to plant death is more rapid. Early symptoms include white, fluffy fungal growth on the stem that extends around the bulb base. Small, dark, over-wintering structures called sclerotia form in the decayed tissue.
    The fungus that causes basal rot prefers high temperatures. It is often considered a weak pathogen, as it will attack plants already damaged by other diseases or insects. Initial infection often occurs through the basal plate, but not all infected bulbs show disease symptoms. The pathogen is often spread through fields by infected seed or through movement of soil and other debris, transfer from tools or equipment, and in irrigation water.
    The fungus that causes white rot prefers temperatures, below 24C. In northern climates, it attacks plants in the spring. The sclerotia can survive in soil for indefinite periods of time in the absence of garlic or other hosts. Sclerotia are stimulated to germinate in the presence of organic sulphur compounds produced by the plants. Once the plants become infected, disease and rot rapidly ensue, either killing the plant outright or causing rot of bulbs later in storage.

    - Prevention and treatments

    Agronomic interventions or Cultural Control:
    If possible, work in clean fields prior to working in fields where infections or infestations have been found. Clean equipment between fields to avoid moving infested soil from one field to another. Additionally, as with any crop, it is important to plant clean healthy seed. For most of the mentioned diseases (Basal Rot, White Rot, Downy Mildew and Nematode infestation), once the pathogen is established in a field, rotation away from Allium spp. for several years is an essential management tool. Schematically:
    Chemical measures:
    To realize with the disinfection of cloves, carried out with the following products which are to be used only for this purpose: BACTERIAL DISEASES
    There are numerous bacterial diseases reported on the garlic. They are of limited importance, even if sometimes, under certain environmental conditions, can cause serious damages.
    The bacteriosis can be classified as follows: - Taxonomy of the genera of bacteria causal agents of the mentioned garlic diseases
    Nature: Natura, C. Linnaeus, 1758
    Physical world: Mundus, Plinius
    Natural bodies: Naturalia, Plinius
    Superdomain: Biota
    Domain: Prokaryota
    Kingdom: Bacteria
    Phylum: Proteobacteria
    Class: Gamma Proteobacteria
    Order: Enterobacteriales
    Family: Enterobacteriaceae
    Genus: Pantoea Gavini et al. 1989
    Genus: Erwinia Winslow et al. 1920
    Genus: Dickeya Samson et al. 2005
    Genus: Enterobacter Hormaeche & Edwards 1960

    Nature: Natura, C. Linnaeus, 1758
    Physical world: Mundus, Plinius
    Natural bodies: Naturalia, Plinius
    Superdomain: Biota
    Domain: Prokaryota
    Kingdom: Bacteria
    Phylum: Proteobacteria
    Class: Gamma Proteobacteria
    Order: Pseudomonadales
    Family: Pseudomonadaceae
    Genus: Pseudomonas Migula 1894

    Nature: Natura, C. Linnaeus, 1758
    Physical world: Mundus, Plinius
    Natural bodies: Naturalia, Plinius
    Superdomain: Biota
    Domain: Prokaryota
    Kingdom: Bacteria
    Phylum: Proteobacteria
    Class: Gamma Proteobacteria
    Order: Xanthomonadales
    Family: Xanthomonadaceae
    Genus: Xanthomonas Dowson 1939

    Nature: Natura, C. Linnaeus, 1758
    Physical world: Mundus, Plinius
    Natural bodies: Naturalia, Plinius
    Superdomain: Biota
    Domain: Prokaryota
    Kingdom: Bacteria
    Phylum: Proteobacteria
    Class: Beta Proteobacteria
    Order: Rhizobiales
    Family: Rhizobiaceae
    Genus: Burkholderia Yabuuchi et al. 1993 emend. Gillis et al. 1995


  • Iris yellow spot tospovirus (IYSV)
  • :

  • Leek yellow stripe virus (LYSV)
  • :

  • Garlic common latent carlavirus (GCLV)
  • :

  • Onion yellow dwarf virus (OYDV)
  • :

    Mosca della cipolla e dell’aglio
    Nome scientifico: Delia antiqua Meigen, 1826

    - Inquadramento sistematico di Delia antiqua
    Regno: Animalia
    Phylum: Arthropoda
    Classe: Insecta
    Ordine: Diptera
    Famiglia: Anthomyiidae
    Genere: Delia
    Specie: Delia antiqua

    Il danno provocato dal dittero antomide Delia antiqua il cui adulto (circa 6-7 mm di lunghezza) ha il corpo di colore grigio-nerastro. La larva, apoda e giallognola, presenta il corpo che si restringe verso l’estremit cefalica. La Mosca della cipolla infesta i bulbi distruggendone i tessuti di cui si nutre; inoltre i bulbi infestati vengono invasi da batteri che ne determinano la decomposizione.
    La Delia antiqua sverna come pupa, nel terreno. All’inizio della primavera sfarfallano gli adulti; le femmine, dopo l’accoppiamento, depongono le uova sui bulbi ed alla base delle piante. Da queste uova, dopo circa una settimana, fuoriescono le larve che penetrano all’interno del bulbo, dove rimangono fino al raggiungimento della maturit; questa viene raggiunta in un arco di tempo che varia da 3 a 6 settimane, a seconda delle temperature ambientali. Raggiunta la maturit le larve abbandonano il bulbo, per andare ad impuparsi nel terreno. Nell’arco dell’anno si possono compiere anche 3-4 generazioni, per cui l’insetto, nei climi pi miti, pu rimanere in campo anche nell’autunno inoltrato. Inoltre, i bulbi una volta infestati vengono attaccati da batteri che determinano la morte della pianta.
    La lotta contro la Mosca della cipolla e di tipo agronomico e di tipo chimico. La lotta agronomica consiste essenzialmente nell’attuazione di semine posticipate, per evitare i danni della 1a generazione che la pi pericolosa. La lotta chimica pu essere di tipo preventivo e consiste nella disinfezione del terreno, specialmente nelle zone dove la presenza del fitofago costante. Inoltre, si pu attuare una lotta chimica anche con colture in atto; in questo caso si interviene o sugli adulti in fase di sfarfallamento o sugli stadi giovanili originati.

    Mosca (Suillia univitata)
    Interventi specifici:- catture con attrattivi alimentari degli adulti svernanti.

    Verme rosso
    Nome scientifico: Dyspessa ulula Borkhausen, 1790

    - Inquadramento sistematico di Dyspessa ulula
    Regno: Animalia
    Phylum: Arthropoda
    Classe: Insecta
    Ordine: Lepidoptera
    Famiglia: Cossidae
    Genere: Dyspessa
    Specie: Dyspessa ulula

    E’ un lepidottero della famiglia dei Cossidae, le cui larve attaccano i bulbi in campo attraverso una galleria che riempiono di escrementi durante la fase di maturazione e quando l'infestazione pi grave svuotano buona parte dei bulbi. L’attivit delle larve continua in magazzino passando da un bulbo all’altro, riuscendo a causare notevoli danni. Gli adulti sfarfallano dalla met di giugno a met luglio, si accoppiano e depongono le uova alla base delle piante. Le larve penetrano nei bulbi praticando un foro nelle tuniche e scavando una galleria completano lo sviluppo dopo circa 40 giorni, si incrisalidano nelle anfrattuosita dei magazzini o nel terreno per poi sfarfallare in primavera.
    La difesa basata su misure agronomiche consistenti nella distruzione dei bulbi infestati al momento della raccolta e immagazzinando separatamente la produzione sospetta o lievemente infestata.
    Dei buoni risultati sono stati ottenuti con Spinosad, intervenendo, al massimo, una volta all’anno, oppure con Etofenprox al massimo 1 intervento all'anno che efficace anche contro la mosca.

    Culinary uses
    Garlic is widely used around the world for its pungent flavour as a seasoning or condiment. It is a fundamental component in many or most dishes of various regions, including eastern Asia, south Asia, Southeast Asia, the Middle East, northern Africa, southern Europe, and parts of South and Central America.
    The flavour varies in intensity and aroma with the different cooking methods (figure 21). It is often paired with onion, tomato, or ginger. The parchment-like skin is much like the skin of an onion and is typically removed before using in raw or cooked form. An alternative is to cut the top off the bulb, coat the cloves by dribbling olive oil (or other oil-based seasoning) over them, and roast them in an oven.
    Garlic softens and can be extracted from the cloves by squeezing the end of the bulb (root), or individually by squeezing one end of the clove. In Korea, heads of garlic are fermented at high temperature; the resulting product, called black garlic, is sweet and syrupy, and is now being sold in the United States, United Kingdom and Australia.
    Garlic may be applied to breads to create a variety of classic dishes such as garlic bread (bread topped with garlic and olive oil or butter, figure 22), garlic toast, bruschetta, crostini and canap (figure 23).

    Figure 21 – Garlic being crushed using a garlic press. Figure 22 – Bread topped with garlic and olive oil or butter. Figure 23 – Garlic being rubbed onto slice of bread.

    Oils can be flavoured with garlic cloves. These infused oils are used to season all categories of vegetables, meats, breads and pasta.
    In some cuisine, the young bulbs are pickled for 3–6 weeks in a mixture of sugar, salt, and spices. In eastern Europe, the shoots are pickled and eaten as an appetizer.
    Immature scapes are tender and edible. They are also known as "garlic spears", "stems", or "tops". Scapes generally have a milder taste than the cloves. They are often used in stir frying or braised like asparagus. Garlic leaves are a popular vegetable in many parts of Asia. The leaves are cut, cleaned, and then stir-fried with eggs, meat, or vegetables.
    Mixing garlic with egg yolks and olive oil produces aioli (garlic mayonnaise). Garlic, oil, and a chunky base produce skordalia. Skordalia is a thick puree (or sauce, dip, spread, etc.) in Greek cuisine made by combining crushed garlic with a bulky base - which may be a pure of potatoes, walnuts, almonds, or liquid-soaked stale bread - and then beating in olive oil to make a smooth emulsion. Blending garlic, almond, oil, and soaked bread produces ajoblanco. The ajoblanco is a popular Spanish cold soup typical from Granada and Mlaga (Andalusia). It is also a common dish in Extremadura (Ajo Blanco Extremeo). This dish is made of bread, crushed almonds, garlic, water, olive oil, salt and sometimes vinegar. It is usually served with grapes or slices of melon
    Garlic powder has a different taste from fresh garlic. If used as a substitute for fresh garlic, 1/8 teaspoon of garlic powder is equivalent to one clove of garlic.

    Domestically, garlic is stored warm (above 18 C) and dry to keep it dormant (so that it does not sprout). It is traditionally hung; softneck varieties are often braided in strands, called "plaits" or grappes. Garlic is often kept in oil to produce flavoured oil; however, the practice requires measures to be taken to prevent the garlic from spoiling. Untreated garlic kept in oil can support the growth of deadly Clostridium botulinum. Refrigeration will not assure the safety of garlic kept in oil. Peeled cloves may be stored in wine or vinegar in the refrigerator. Commercially prepared oils are widely available, but when preparing and storing garlic-infused oil at home, there is a risk of botulism if the product is not stored properly. To reduce this risk, the oil should be refrigerated and used within one week. Manufacturers add acids and/or other chemicals to eliminate the risk of botulism in their products. Two outbreaks of botulism related to garlic stored in oil have been reported. Commercially, garlic is stored at 0 C, in a dry, low humidity environment. Garlic will keep longer if the tops remain attached. Ready peeled garlic cloves sold in a plastic container (figure 24).

    Figure 24 – Ready peeled garlic cloves sold in a plastic container.

    Historical uses
    Garlic has been used as both food and medicine in many cultures for thousands of years, dating at least as far back as the time that the Giza pyramids were built. Garlic is still grown in Egypt, but the Syrian variety is the kind most esteemed now.
    Garlic is mentioned in the Bible and the Talmud. Hippocrates, Galen, Pliny the Elder, and Dioscorides all mention the use of garlic for many conditions, including parasites, respiratory problems, poor digestion, and low energy. Its use in China was first mentioned in A.D. 510.
    It was consumed by ancient Greek and Roman soldiers, sailors, and rural classes (Virgil, Ecologues ii. 11), and, according to Pliny the Elder (Natural History xix. 32), by the African peasantry. Galen eulogizes it as the "rustic's theriac" (see F. Adams' Paulus Aegineta, p. 99), and Alexander Neckam, a writer of the 12th century (see Wright's edition of his works, p. 473, 1863), recommends it as a palliative for the heat of the sun in field labour.
    In the account of Korea's establishment as a nation, gods were said to have given mortal women with bear and tiger temperaments an immortal's black garlic before mating with them.
    This is a genetically unique six-clove garlic that was to have given the women supernatural powers and immortality. This garlic is still cultivated in a few mountain areas today.
    In his Natural History, Pliny gives an exceedingly long list of scenarios in which it was considered beneficial (N.H. xx. 23). Dr. T. Sydenham valued it as an application in confluent smallpox, and, says Cullen (Mat. Med. ii. p. 174, 1789), found some dropsies cured by it alone. Early in the 20th century, it was sometimes used in the treatment of pulmonary tuberculosis or phthisis. dropsies Garlic was rare in traditional English cuisine (though it is said to have been grown in England before 1548) and has been a much more common ingredient in Mediterranean Europe. Garlic was placed by the ancient Greeks on the piles of stones at crossroads, as a supper for Hecate (Theophrastus, Characters, The Superstitious Man). A similar practice of hanging garlic, lemon and red chilli at the door or in a shop to ward off potential evil is still very common in India.
    According to Pliny, garlic and onions were invoked as deities by the Egyptians at the taking of oaths. Pliny also states that garlic demagnetizes lodestones, which is not factual.
    The inhabitants of Pelusium, in lower Egypt (who worshiped the onion), are said to have had an aversion to both onions and garlic as food.
    To prevent the plant from running to leaf, Pliny (N.H. xix. 34) advised bending the stalk downward and covering with earth; seeding, he observes, may be prevented by twisting the stalk (by "seeding", he most likely meant the development of small, less potent bulbs).

    Medicinal use and health benefits
    In test tube studies, garlic has been found to have antibacterial, antiviral, and antifungal activity. However, these actions are less clear in humans. Garlic is also claimed to help prevent heart disease (including atherosclerosis, high cholesterol, and high blood pressure) and cancer. Garlic is used to prevent certain types of cancer, including stomach and colon cancers. In fact, countries where garlic is consumed in higher amounts, because of traditional cuisine, have been found to have a lower prevalence of cancer.
    Animal studies, and some early investigational studies in humans, have suggested possible cardiovascular benefits of garlic. A Czech study found that garlic supplementation reduced accumulation of cholesterol on the vascular walls of animals.
    Another study had similar results, with garlic supplementation significantly reducing aortic plaque deposits of cholesterol-fed rabbits. Another study showed that supplementation with garlic extract inhibited vascular calcification in human patients with high blood cholesterol.
    The known vasodilative effect of garlic is possibly caused by catabolism of garlic-derived polysulfides to hydrogen sulphide in red blood cells, a reaction that is dependent on reduced thiols in or on the RBC membrane. Hydrogen sulphide is an endogenous cardioprotective vascular cell-signaling molecule.
    Although these studies showed protective vascular changes in garlic-fed subjects, a randomized clinical trial funded by the National Institutes of Health (NIH) in the United States and published in the Archives of Internal Medicine in 2007 found that the consumption of garlic in any form did not reduce blood cholesterol levels in patients with moderately high baseline cholesterol levels.
    According to the, "despite decades of research suggesting that garlic can improve cholesterol profiles, a new NIH-funded trial found absolutely no effects of raw garlic or garlic supplements on LDL, HDL, or triglycerides... The findings underscore the hazards of meta-analyses made up of small, flawed studies and the value of rigorously studying popular herbal remedies."
    In 2007, the BBC reported that Allium sativum may have other beneficial properties, such as preventing and fighting the common cold. This assertion has the backing of long tradition in herbal medicine, which has used garlic for hoarseness and coughs. The Cherokee also used it as an expectorant for coughs and croup.
    Allium sativum has been found to reduce platelet aggregation and hyperlipidemia.
    Garlic is also alleged to help regulate blood sugar levels. Regular and prolonged use of therapeutic amounts of aged garlic extracts lower blood homocysteine levels and has shown to prevent some complications of diabetes mellitus. People taking insulin should not consume medicinal amounts of garlic without consulting a physician.
    In 1858, Louis Pasteur observed garlic's antibacterial activity, and it was used as an antiseptic to prevent gangrene during World War I and World War II. More recently, it has been found from a clinical trial that a mouthwash containing 2.5% fresh garlic shows good antimicrobial activity, although the majority of the participants reported an unpleasant taste and halitosis.
    Garlic cloves are used as a remedy for infections (especially chest problems), digestive disorders, and fungal infections such as thrush.
    Garlic has been found to enhance thiamine absorption and therefore reduce the likelihood for developing the thiamine deficiency beriberi.
    In 1924, it was found that garlic is an effective way to prevent scurvy, because of its high vitamin C content.
    Garlic has been used reasonably successfully in AIDS patients to treat cryptosporidium in an uncontrolled study in China. It has also been used by at least one AIDS patient to treat toxoplasmosis, another protozoa disease.
    Garlic supplementation in rats, along with a high protein diet, has been shown to boost testosterone levels.
    A 2010 double-blind, parallel, randomised, placebo-controlled trial involving 50 patients whose routine clinical records in general practice documented treated but uncontrolled hypertension. Concluded that "Our trial suggests that aged garlic extract is superior to placebo in lowering systolic blood pressure similarly to current first line medications in patients with treated but uncontrolled hypertension."

    Adverse effects and toxicology
    Garlic is known for causing halitosis as well as causing sweat to have a pungent 'garlicky' smell which is caused by allyl methyl sulphide (AMS). AMS is a gas which is absorbed into the blood during the metabolism of garlic; from the blood it travels to the lungs (and from there to the mouth causing bad breath) and skin where it is exuded through skin pores. Washing the skin with soap is only a partial and imperfect solution to the smell. Studies have shown that sipping milk at the same time as consuming garlic can significantly neutralize bad breath. Mixing garlic with milk in the mouth before swallowing reduced the odour better than drinking milk afterward. Plain water, mushrooms and basil may also reduce the odour; the mix of fat and water found in milk, however, was the most effective.
    Raw garlic is more potent; cooking garlic reduces the effect. The green dry 'folds' in the centre of the garlic clove are especially pungent. The sulphur compound allicin, produced by crushing or chewing fresh garlic produces other sulphur compounds: ajoene, allyl sulphides, and vinyldithiins.
    Aged garlic lacks allicin, but may have some activity due to the presence of S-allylcysteine.
    In a rat study, allicin was found to be an activator of TRPA1. The neurons released neurotransmitters in the spinal cord to generate pain signals and released neuropeptides at the site of sensory nerve activation, resulting in vasodilatation as well as inflammation. Allicin is released only by crushing or chewing raw garlic and cannot be formed from cooked garlic.
    Some people suffer from allergies to garlic and other plants in the allium family. Symptoms can include irritable bowel, diarrhea, mouth and throat ulcerations, nausea, breathing difficulties, and in rare cases anaphylaxis. Garlic-sensitive patients show positive tests to diallyl disulfide, allylpropyldisulfide, allylmercaptan and allicin, all of which are present in garlic. People who suffer from garlic allergies will often be sensitive to many plants in the lily family (Liliaceae), including onions, garlic, chives, leeks, shallots, garden lilies, ginger, and bananas.
    Garlic can also cause indigestion, nausea, vomiting, and diarrhea. It thins the blood (as does aspirin); this had caused very high quantities of garlic and garlic supplements to be linked with an increased risk of bleeding, particularly during pregnancy and after surgery and childbirth, although culinary quantities are safe for consumption. There have been several reports of serious burns resulting from garlic being applied topically for various purposes, including naturopathic uses and acne treatment, so care must be taken to test a small area of skin using a very low concentration of garlic.On the basis of numerous reports of such burns, including burns to children, topical use of raw garlic, as well as insertion of raw garlic into body cavities, is discouraged. In particular, topical application of raw garlic to young children is not advisable. The side effects of long-term garlic supplementation, if any exist, are largely unknown, and no FDA-approved study has been performed. However, garlic has been consumed for several thousand years without any adverse long-term effects, suggesting that modest quantities of garlic pose, at worst, minimal risks to normal individuals. Possible side effects include gastrointestinal discomfort, sweating, dizziness, allergic reactions, bleeding, and menstrual irregularities. The safety of garlic supplements had not been determined for children.; some breastfeeding mothers have found their babies slow to feed and have noted a garlic odour coming from their baby when they have consumed garlic. Garlic may interact with warfarin (an blod anticoagulant, antiplatelets ) (antiaggregant of blood), saquinavir (antiretroviral), antihypertensives, calcium channel blockers, and hypoglycemic drugs, as well as other medications. Members of the allium family might be toxic to cats or dogs.
    Some degree of liver toxicity has been demonstrated in rats, particularly in extremely large quantities exceeding those that a rat would consume under normal situations.

    When crushed, Allium sativum yields allicin, an antibiotic and antifungal compound (phytoncide, that are antimicrobial allelochemic volatile organic compounds derived from plants). It has been claimed that it can be used as a home remedy to help speed recovery from strep throat or other minor ailments because of its antibiotic properties. It also contains the sulphur containing compounds such as alliin, ajoene, diallylsulfide, dithiin, S-allylcysteine, and enzymes, vitamin B, proteins, minerals, saponins, flavonoids, and maillard reaction products, which are non-sulphur containing compounds.
    Furthermore a phytoalexin called “allixi” was found, a non-sulphur compound with a γ-pyrone skeleton structure with anti-oxidative effects, anti-microbial effects, anti-tumor promoting effects, inhibition of aflatoxin B2 DNA binding, and neurotrophic effects.
    Allixin showed an anti-tumor promoting effect in vivo, inhibiting skin tumor formation by TPA and DMBA initiated mice. Analogs of this compound have exhibited anti tumor promoting effects in in vitro experimental conditions. Herein, allixin and/or its analogs may be expected useful compounds for cancer prevention or chemotherapy agents for other diseases.
    The composition of the bulbs is approximately 84.09% water, 13.38% organic matter, and 1.53% inorganic matter, while the leaves are 87.14% water, 11.27% organic matter, and 1.59% inorganic matter.
    The phytochemicals responsible for the sharp flavour of garlic are produced when the plant's cells are damaged. When a cell is broken by chopping, chewing, or crushing, enzymes stored in cell vacuoles trigger the breakdown of several sulphur-containing compounds stored in the cell fluids. The resultant compounds are responsible for the sharp or hot taste and strong smell of garlic. Some of the compounds are unstable and continue to evolve over time. Among the members of the onion family, garlic has by far the highest concentrations of initial reaction products, making garlic much more potent than onions, shallots, or leeks. Although many humans enjoy the taste of garlic, these compounds are believed to have evolved as a defensive mechanism, deterring animals like birds, insects, and worms from eating the plant.
    A large number of sulphur compounds contribute to the smell and taste of garlic. Diallyl disulfide is believed to be an important odour component. Allicin has been found to be the compound most responsible for the "hot" sensation of raw garlic. This chemical opens thermoTRP (transient receptor potential) channels that are responsible for the burning sense of heat in foods. The process of cooking garlic removes allicin, thus mellowing its spiciness.
    Because of its strong odour, garlic is sometimes called the "stinking rose". When eaten in quantity, garlic may be strongly evident in the diner's sweat and breath the following day. This is because garlic's strong-smelling sulphur compounds are metabolized, forming allyl methyl sulphide. Allyl methyl sulphide (AMS) cannot be digested and is passed into the blood. It is carried to the lungs and the skin, where it is excreted. Since digestion takes several hours, and release of AMS several hours more, the effect of eating garlic may be present for a long time.
    This well-known phenomenon of "garlic breath" is alleged to be alleviated by eating fresh parsley. The herb is, therefore, included in many garlic recipes, such as pistou (or just pistou, is a cold sauce made from cloves of garlic, fresh basil, and olive oil), persillade (a sauce or seasoning mixture of parsley chopped together with seasonings including garlic, herbs, oil, and vinegar), and the garlic butter spread used in garlic bread (figure 13). However, since the odour results mainly from digestive processes placing compounds such as AMS in the blood, and AMS is then released through the lungs over the course of many hours, eating parsley provides only a temporary masking. One way of accelerating the release of AMS from the body is the use of a sauna.
    Because of the AMS in the bloodstream, it is believed by some to act as a mosquito repellent.
    However, there is no evidence to suggest that garlic is actually effective for this purpose.

    Community rules for the quality of garlic (CEE rule n. 2288/97)


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