Phenotypic characterization and quality traits of Greek garlic (Allium sativum L.) germplasm cultivated at two different locations

Abstract

In the present study, we examined the phenotypic diversity of Greek garlic (Allium sativum L.) genotypes using morphological descriptors derived from IPGRI and UPOV. Thirty-four garlic genotypes were cultivated at two different locations: (a) Velestino, Magnesia, Region of Thessaly, and (b) Kavasila, Ilia, Region of Western Greece. The garlic genotypes were characterized using twenty-seven morphological descriptors and four quantitative characters, namely bulb dry matter, chlorophyll content in the leaf, yield and total soluble solids (°Brix) of plants and raw bulbs. The Shannon–Weaver (H′) phenotypic diversity index varied among the genotypes, although identical mean values (0.79) were recorded for both fields. Traits, such as flowering stem length, bulb skin color, skin color of the clove presented low (H′) values indicating a high coefficient of heritability and less environmental effect. Principal component analysis based on morphological characters showed that the first seven axes could explain 71.49% and 75.86% of total variation for Kavasila and Velestino fields respectively. Significant differences were also observed among the garlic genotypes for the quantitative characters studied. Furthermore, significant statistical correlations were recorded for specific characters between the two cultivation sites e.g. yield with weight of cloves (r = 0.55 and r = 0.62) and number of cloves per bulb with weight of cloves (r = −0.51 and r = −0.55), which could be exploited further in future breeding programs. In conclusion, the high phenotypic diversity observed among the garlic genotypes could be attributed to various factors such as the genotype, the cultivation practices and the environmental conditions.