Shelf-Life Assessment of Wettable Powder (WP) Formulations of the Entomopathogenic Fungi Nomuraea rileyi (Farlow) Samson

Studies on the effect of storage on viability of developed Nomuraea rileyi (Farlow) Samson 5 % WP formulation A(N₃₀S_1/1) and B(N₃₀T_1/2G_2/1H_1/1) (comprising adjuvants, fungus and kaolinite) and N.rileyi alone in kaolinite (control) on viability of the fungus are undertaken. At 10 DAI, surface coverage varied from 100 to 36.67, 100 to 33.33 and 100 to 0.0 per cent in formulation A, B and control, respectively from 0 to 300 days storage samples. The formulations A and B stored upto 150 days showed cent per cent surface coverage against the 71.70 per cent in control.Cfu count varied from 24.33 to 1.33x10⁸, 23.67 to 1.33x10⁸ and 23.33 to 0x10⁸cfu/ml in formulation A, B and control, respectively from 0 to 300 days storage. Formulation A and B maintained their superiority over the control viability of the inoculums, while formulation without adjuvants recorded decline in viability. The reduction in cfu was rapid from 270 to 300 days. Considering surface coverage (%), biomass produced and viability (cfu/g) the N.rileyi 5%WP formulation A, B and control could be stored upto 10, 10 and 7 months, respectively for maximum cfu count of 1x10⁸/g for WP formulations as per norms.