Sclerotium rolfsii (Sacc.), causing collar rot (CR) of chickpea is one of the most perilous soil-borne pathogens that parasitize chickpea at a very
early stage, therefore, leading to huge yield loss. The present experiment aimed to study the relative changes in defence-related enzymes and
phenolics which take place in chickpea (both in resistant and susceptible genotypes) upon CR infection. Emphasis was given to study the changes
in total soluble proteins, peroxidase and total phenol content at 7, 14, and 21-days post inoculation (dpi). The experiment was set up by taking
moderately resistant (MR), moderately susceptible (MS), susceptible (S) and highly susceptible (HS) genotypes and the experiment was conducted
under both inoculated and non-inoculated conditions. The results indicated that total phenol content was signicantly higher (3 folds) at 7dpi and
then declined gradually upto 21dpi. MR cultivars had higher phenol content than the (MS) and the susceptible non-inoculated control. Total soluble
protein content decreased with the days after post-inoculation and this reduction is greater in the susceptible cultivar as compared to the MR
cultivars. Total soluble protein content was 3 times higher in the inoculated cultivars than in the in-inoculated control. Peroxidase (POD) activity
was also decreased from 7dpi to 21dpi and maximum POD activity was recorded at 7dpi in MR cultivars (12.61 g-1 fresh wt.) than the susceptible
one (1.31 g-1 fresh wt.). Scanning electron microscopy (SEM) was also done to compare the extent of the mycelial network within the xylem
vessels of inoculated MR, MS and susceptible cultivars.