Annals of Plant Protection Sciences

The most destructive among the biotic stresses in chick-pea is the blight caused by Ascochyta rabiei. Variability in isolates of Ascochyta rabiei both in terms of virulence analysis and molecular characterization was studied. The nine morphologically alike isolates of A. rabiei representing different geographical regions were subjected to virulence analysis on differential chick pea genotypes. These were divided into seven distinct pathotypes based on their disease reaction. The isolates from Kashmir ArK₁ and ArK₂ were found to be least virulent while ArG₁ from Gurdaspur was most virulent. Rapid amplification of polymorphic DNA (RAPD) was carried out based on (UPGMA) clustering analysis; the isolates were divided into two major groups. The least virulent isolate ArK₁ and ArK₂ were separated from rest of the isolates, which showed that correlation existed between virulence analysis and RAPD pattern. The investigation also resulted in identification of useful molecular markers for separation of different isolates.