Description
Garlic (Allium sativum) is a species of bulbous flowering plant in the genus Allium. Its close relatives
include the onion, shallot, leek, chive, Welsh onion and Chinese onion. It is native to Central Asia and northeastern Iran and has long been used as a seasoning worldwide, with a history of several thousand years of human consumption and use. It was known to ancient Egyptians and has been used as both a food flavoring and a traditional medicine.


Properties
Fresh or crushed garlic yields the sulfur-containing compounds allicin ,ajoene ,diallyl polysulfides ,vinyldithiins , and S-allylcysteine ; as well as enzymes, saponins, flavonoids, and Maillard reaction products, which are not sulfur-containing compounds.

Diseases
Garlic plants are usually hardy and not affected by many pests or diseases. Garlic plants are said to repel rabbits and moles .The California Department of Food and Agriculture (CDFA) conducts a certification program to assure freedom from nematode and white rot disease caused by Stromatinia cepivora , two pathogens that can both destroy a crop as well as remain in the soil indefinitely, once introduced. Garlic may also suffer from pink root, a typically non-fatal disease that stunts the roots and turns them pink or red; or leek rust,The larvae of the leek moth attack garlic by mining into the leaves or bulbs.
Botrytis neck and bulb rot is a disease of onion, garlic, leek and shallot.
Botrytis allii and Botrytis aclada cause this disease in onion and Botrytis porri causes it in garlic. “ Initial symptoms usually begin at the neck, where affected tissue softens, becomes water-soaked, and turns brown. In a humid atmosphere, a gray and feltlike growth (where spores are produced) appears on rotting scales, and mycelia may develop between scales. Dark-brown-to-black sclerotia (the resting bodies of the pathogen) may eventually develop in the neck or between scales.
Adverse effects and toxicology
Garlic is known to cause bad breath (halitosis) and body odor, described as a pungent garlicky smell to sweat.
This is caused by allyl methyl sulfide (AMS). AMS is a volatile liquid which is absorbed into the blood during the metabolism of garlic-derived sulfur compounds; from the blood it travels to the lungs (and from there to the mouth, causing bad breath; see garlic 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 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 odor better than drinking milk afterward. Plain water, mushrooms, and basil may also reduce the odor; the mix of fat and water found in milk, however, was the most effective.
The green, dry "folds" in the center of the garlic clove are especially pungent.
The sulfur compound allicin, produced by crushing or chewing fresh garlic, produces other sulfur compounds: ajoene, allyl polysulfides, and vinyldithiins. Aged garlic lacks allicin, but may have some activity due to the presence of S-allylcysteine.
Some people suffer from IRAN to garlic and other species of Allium. Symptoms can include irritable bowel, diarrhea, mouth and throat ulcerations, nausea, breathing difficulties, and, in rare cases, anaphylaxis. Garlic-sensitive people show positive tests to diallyl disulfide, allylpropyldisulfide, allylmercaptan, and allicin, all of which are present in garlic.
People who suffer from garlic allergies are often sensitive to many other plants, including onions, chives, leeks, shallots, garden lilies, ginger, and bananas.
If higher-than-recommended doses of garlic are taken with anticoagulant medications, this can lead to a higher risk of bleeding.
Garlic may interact with warfarin, saquinavir, antihypertensives, calcium channel blockers, the quinolone family of antibiotics such as ciprofloxacin, and hypoglycemic drugs, as well as other medications.The American Veterinary Medical Association does not recommend feeding garlic to your pets.