Variation in Productive Characteristics and Diversity Assessment of Garlic Cultivars and Lines Using DNA Markers

Garlic cultivars Egyptian, Chinese, and Elephant, and sex Chinese lines were evaluated for their productivity in two field experiments during 2004/2005 and 2005/2006 winter seasons. The results indicated that the maximum plant height was 70.5 and 70.8 cm for Egyptian cultivar in both seasons, respectively. The maximum value of leaves area per plant were observed with Elephant cultivar and Chinese line (L2). Elephant cultivar was superior on the other cultivars and lines in plant fresh weight, while, the Chinese line (L4) had the maximum plant dry weight and the highest chlorophyll content. Bulb fresh and dry weight of Egyptian cultivar (Balady) was the lowest among the cultivars and lines tested. On the other hand, Egyptian cultivar (Balady) produced more cloves number compared with the other cultivars and Chinese lines. Elephant and Chinese cultivars gave the highest mean values of bulb diameter compared with Egyptian cultivar. Also, Chinese lines (L2 and L5) gave higher mean values of bulb diameter compared with the other Chinese lines. The same trend was observed for clove weight. Total soluble solid (TSS) content of cloves was highest in Egyptian cultivar (Balady) and Chinese line 5. Marketable yield (g/m2) showed that Elephant cultivar and Chinese line 5 (L5) produced the highest yield, while Egyptian cultivar (Balady) and Chinese line 6 (L6) produced the lowest yield. Two types of molecular markers, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR), were assayed to determine the genetic diversity of sex garlic lines and three garlic cultivars. A high level of polymorphism among garlic cultivars and lines was found with both RAPD and ISSR markers, while, ISSR revealed higher polymorphism among Chinese lines than RAPD. The UPGMA dendrogram generated from RAPD data clearly indicated four main clusters. The dendrogram generated from ISSR data clearly indicated five clusters. Chinese line (L6) was separated from the other Chinese lines and this line gave the lowest yield and total soluble solid content compared to the other lines and Chinese cultivar. Polymorphic ISSRs are abundant in garlic and demonstrated genetic diversity among related lines. Therefore, ISSR is an additional tool for fingerprinting and detailed assessment of genetic relationships in garlic