Synthesis, Quality Assay and Assessment of Fly Ash-Based Chemical Pesticides for Efficacy against Pests of Crops, Stored Commodities and in Urban Areas

Four fly ash-based insecticides, viz. Fly ash + Endosulfan 4% Dust, Fly ash + Chlorpyriphos 1.5% WDP, Fly ash + Imidacloprid 2.15% Tablet and Fly ash + Fipronil 0.05% Tablet, were synthesized. Fractions of lignite fly ash particles obtained through the ball mill grinder were characterized and fractions which were nearer to nanoparticle (less than 50 μm) were subjected to tests in various experiments. Maximum mean per cent mortality was found in Fly ash + Endosulfan 4% Dust 50% conc. against major pests of rice such as leaf folder, skipper, grasshopper, green horned caterpillar, green leafhopper and brown planthopper followed by Fly ash + Chlorpyriphos 1.5% WDP @ 0.25% which recorded mortality of leaf folder, rice skipper, grasshopper, green horned caterpillar, green leafhopper and brown planthopper. Maximum mortality was found in Fly ash + Endosulfan 4% Dust 50% conc. against major pests of cotton such as spotted bollworm, red cotton bug, aphid, mealy bug and whitefly followed by Fly ash + Chlorpyriphos 1.5% WDP @ 0.25% which recorded higher mortality of spotted bollworm, red cotton bug, aphid, mealy bug and whitefly. In brinjal, Fly ash + Endosulfan 4% Dust 50% conc. controlled major pests such as Epilachna beetle, aphid, mealy bug and lace wing bug followed by Fly ash + Chlorpyriphos 1.5% WDP @ 0.25%. Fly ash + Endosulfan 4% Dust @ 50% conc. gave better control of storage pests such as Tribolium castaneum (Herbst) and Callosobruchus chinensis L. followed by Fly ash + Chlorpyriphos 1.5% WDP @ 0.25%. In the choice test, cockroaches did not accept the test product FA + Imidacloprid, whereas they accepted the product FA + Fipronil to some extent and maximum number of cockroaches got attracted to groundnut candy (>3) in both the experiments and biscuits 2.62 in experiment one and 3.13 in experiment two compared to fipronil (1.5). Overall the preference tests had showed that the out of the two new fly-ash products, FA + Fipronil was found to be potential; however, it might be further enhanced through suitable refinement in the formulation.