Garlic biodiversity and genetic resources

Garlic clones exhibit a wide variation in vegetative traits, flavor and pungency; bolting capacity, and fertility. Cultivar characteristics differ considerably with the location of cultivation, and climate has a significant impact on garlic bulbing, florogenesis and flavor. All cultivated garlic clones are sterile, thus an increase in genetic variation is possible only via random or induced mutations, somaclonal variation and introduction of new genetic variation using modern molecular techniques. Conservation of garlic germplasm began about 30 years ago. Since then, field genebanks were established in Germany, Israel, Poland, Czech Republic, Russia, and the USA. Yet, only limited effort has been invested in systematic collection and preservation of wild Allium species of potential economic value. Isozyme and molecular analyses show considerable genetic diversity within the garlic species complex, and AFLP technology facilitates the evaluation of genetic diversity in garlic collections. Biochemical and molecular studies suggest that the highest level of heterogeneity occurs within the Central Asian gene pool, which may contain genes of interest for future use in genetic studies, as well as for plant improvement programs. Until recently, however, this genepool did not attract much attention by researchers from outside the region. An international effort aimed at immediate collection and preservation of this heritage is imperative. It should be followed by an intensive evaluation effort and accompanied by substantial preservation projects, to halt the rapid and irreversible erosion of the Central Asia genepool of garlic landraces and wild populations