Study on the Genetic Diversity of Ascochyta rabiei Isolates, Cause of Chikpea Blight Disese in Lorestan Province Using SSR Marker

Ascochyta blight caused by Ascochyta rabiei is one of the most destructive diseases affecting chickpea (Cicer arietinum). To study the genetic diversity of the fungus، fifty three isolates were rendomly collected from chikpea fields in eight different regions of Lorestqn Province namely Azna، Aleshtar، Broujerd، Poldokhtar، Chegeni، Khoorramabad، Koohdasht، Noorabad. The isolates were cultured and purified on specific chickpea seed meal dextrose agar medium. Genetic diversity among the population was assayed، employing SSR marker and using five specific primer pairs. Similarity of the isolates was determined using Dice''s coefficient and UPGMA clustering method. Cluster analysis of data revealed that isolates with genetic similarity distance equal to 3% were placed in 9 distinct genetic groups. PCoA analysis of data was done employing Jaccard similarity matrix in NTSYS software. According to the acquired data، from among 53 components، 15 components stood within an Eigenvalue greater than 1 with 90. 49 % of variation being justified. Analysis of mOlecular vAriance (AMOVA) revealed the highest genetic variation (96%) within populations while distributed among populations by 4%. The results finally indicated that there is considerable genetic diversity among and between the isolates collected from different regions of the province.