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Virulence analysis of 64 isolates of Fusarium oxysporum f. sp. ciceris causing chickpea wilt collected from major chickpea growing states of India on 14 varieties, including 10 international differentials revealed that the isolates from each state were highly variable. Based on the reactions on international differentials, more than one race was found to be prevalent in every state. Majority of the isolates were not matched with the race specific reactions. Therefore, some of the cultivars, namely, GPF 2, DCP 92-3, and KWR 108 should be included as new differentials to obtain clear-cut differential responses. Randomly amplified polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR), and simple sequence repeat (SSR) markers were used to assess the genetic diversity of these isolates. Unweighted paired group method with arithmetic average (UPGMA) cluster analysis was used to divide the isolates into distinct clusters. The clusters generated by RAPD grouped all isolates into three categories at 25% genetic similarity and into two major categories at 30% genetic similarity. ISSR and SSR analyses also grouped all the isolates into two major categories. Majority of the isolates from Punjab and a few from Rajasthan were grouped in one category while the isolates from all other states were grouped in another suggesting the existence of diverse genetic populations of the pathogen at the same location. Some of the RAPD (OPM 6, OPI 9, P 17, OPN 4, OPF 1, P 17, P 21, and SC 1), ISSR (ISSR 7, ISSR 11, and ISSR 12) and SSR (MB 17) markers clearly distinguished area specific isolates.

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Genetic diversity of 89 isolates of Rhizoctonia solani isolated from different pulse crops representing 21 states from 16 agro-ecological regions of India, 49 morphological, and 7 anastomosis groups (AGs) was analyzed using 12 universal rice primers (URPs), 22 random amplified polymorphic DNA (RAPD), and 23 inter-simple sequence repeats (ISSR) markers. Both URPs and RAPD markers provided 100 % polymorphism with the bands ranging from 0.1 to 5 kb in size, whereas ISSR markers gave 99.7 % polymorphism with the bands sizes ranging from 0.1 to 3 kb. The marker URP 38F followed by URP13R, URP25F, and URP30F, RAPD marker R1 followed by OPM6, A3 and OPA12 and ISSR3 followed by ISSR1, ISSR4, and ISSR20 produced the highest number of amplicons. R. solani isolates showed a high level of genetic diversity. Unweighted pair group method with an arithmetic average (UPGMA) analysis grouped the isolates into 7 major clusters at 35 % genetic similarity using the three sets of markers evaluated. In spite of using three different types of markers, about 95 % isolates shared common grouping patterns. The majority of the isolates representing various AGs were grouped together into different sub-clusters using all three types of markers. Molecular groups of the isolates did not correspond to agro-ecological regions or states and crops of the origin. An attempt was made for the first time in the present study to determine the genetic diversity of R. solani populations isolated from different pulse crops representing various AGs and agro-ecological regions.