Genetic Diversity and Mating Type Distribution of Ascochyta rabiei Populations Affecting Chickpea

Chickpea Ascochyta blight, Ascochyta rabiei is the most important disease of chickpea in many countries. Understanding the genetic diversity of the pathogen is very important to identify resistance sources to virulent populations in national and international chickpea breeding programs. Moreover, knowledge on the existence of mating types can help to fine tune Ascochyta blight management practices. Eight simple sequence repeats (SSR) markers were used to estimate the genetic diversity of 96 isolates collected from four countries (Uzbekistan, Syria, Lebanon, and Turkey). A total of 29 bands were recorded of which 26 were polymorphic. The study showed that the isolates were genetically diverse and isolates from Uzbekistan showed the highest diversity. Following phylogenetic analysis, the isolates were clustered into four groups and isolates from Uzbekistan were distributed in all groups. The two mating types were found in the four countries and no significant deviation from 1:1 ratio for Turkey and Uzbekistan isolates. Keywords: Ascochyta rabiei, SSR markers, diversity, mating type.