Pathogenicity of entomopathogenic bacteria isolated from white grub Brahmina coriacea on its lifestages

Six highly potential bacterial strains viz., Bacillus cereus strain CPRI14, Psychrobacter pulmonis strain CPRI4, Bacillus pumilus strain CPRI8, Bacillus psychrodurans strain CPRI3, Novosphingobium capsulatum CPRI12 and Paenibacillus tylopili strain CPRI7 isolated from grubs of Brahmina coriacea were evaluated on second and third instar grubs of B. coriacea. Bacillus cereus, P. pulmonis, B. pumilus and B. psychrodurans were evaluated on adult and egg stages of B. coriacea. Pathogenicity tests were performed at 1.0x 10⁸ cfu/ml of broth. Mortality levels observed were 92.59% and 100% with B. cereus and 67.41 and 81.85% with P. pulmonis within 30 and 45 days, respectively. Similar trend was observed with third instar grubs and no or only few adults emerged from these. After 15 days, 83.33% beetle mortality was observed due to B. cereus.