Evaluation of genetic diversity and phenotypic description of garlic (Allium sativum L.) from the Czech field collection

The main objective of gene banks is the rescue, preservation, and evaluation of genetic resources. The gene bank in Olomouc houses a collection of garlic (Allium sativum L.) that is significant in Europe. This study focused on the diversity of the garlic collection at the genotype and phenotype levels. While the phenotypic description data allowed only the distinction between bolting and nonbolting garlic varieties, cluster and population structure analyses calculated from the microsatellite analysis data revealed that there were six genetic populations in the data: four populations of bolting garlic cultivars and two nonbolting cultivars. The bolting garlic genetic populations K1-K4 were more differentiated (Fst = 0.38) and showed higher overall diversity (I = 0.94) than the nonbolting garlic genetic populations. A high correlation was found between genotype and phenotype (R = 0.88; p <= 0.01). Descriptors Ability to produce scapes, Number of bulbils, Colour of the bulb skin, and 100-bulbil weight play the major role in the K1-K6 genetic grouping. Yield study showed that Weight of clove contributes more to higher average bulb weight than the trait Average number of cloves. The highest yield showed genetic populations K5 and K6. The study also showed that for some genotypes, the environment changed the phenotypic expression of the garlic type regardless of the genetic background.