Molecular analysis of Ascochyta rabiei (Pass.) Labr., the pathogen of ascochyta blight in chickpea

Genetic diversity in Ascochyta rabiei (Pass.) Labr., the causative agent of ascochyta blight of chickpea, was determined using 37 Indian, five America n (USA), three Syrian, and two Pakistani isolates. A total of 48 polymorphi c RAPD markers were scored for each isolate and the data used for cluster a nalysis. Most of the isolates clustered in the dendrogram essentially accor ding to geographic origin. Based on the two major clusters A and B, Indian isolates were grouped into two categories, type-A and type-B. Isolates of A . rabiei within the Punjab state were more diverse than isolates from other states in northwestern India. A DNA marker (ubc756(1.6 kb)), specific to I ndian isolates was identified. This is the first report of a molecular dive rsity analysis of Indian isolates of A. rabiei. The information may assist Indian chickpea breeders in the proper deployment of blight-resistant culti vars and in disease management.