Cyanide production was assessed on YEMA medium supplemented with glycine and inverted with filter paper impregnated with picric acid and sodium carbonate placed in the lid of each Petri plate.Change in colour after incubation from yellow to light brown or reddish brown indicated HCN production (Plate 1). Out of 20 soil and chickpea nodule isolates along with reference Mesorhizobium spp. LGR 33 tested, 33% isolates were found positive for HCN production (Table 2). Siderophore production was tested by streaking soil and chickpea nodule isolates on CAS agar medium. Appearance of clear halo zones around the colony due to chelation of iron bound to CAS dye indicated the production of siderophore zone after 48 h of incubation (Plate 2). Out of 20 isolates of soil and chickpea nodules including LGR 33 (reference), 43% were able to produce siderophores (Table 2). Out of 20 isolates of soil and chickpea nodules 57% (12) were able to produce protease on skim milk agar and 62% (13) were able to produce cellulase on CMC agar media (Table 2).
The antagonistic e