Toxicological and genotoxic evaluation of dichlorvos on multivoltine races of silkworm (Bombyx mori L.)

The silkworm Bombyx mori L. is essential for silk production. This species may be at risk from dichlorvos (DDVP), an organophosphate pesticide commonly used in agriculture and sericulture. This study evaluates the harmful effects of dichlorvos on the Pure Mysore and C-nichi multivoltine races of B. mori. We exposed larvae to sublethal doses of dichlorvos at 2, 5, 10, and 15 ppm using a leaf-dip method. We measured protein content, adult lifespan, dominant lethal mutations, and economic traits like larval weight, cocoon and shell weight, shell ratio, and filament length. The results showed a dose-dependent decline in economic traits and total protein concentration, with C-nichi being more sensitive than Pure Mysore. The adult lifespan gradually decreased with higher doses of Dichlorvos. Dominant lethal experiments confirmed significant genotoxic effects at 10 and 15 ppm. These findings suggest that even low levels of Dichlorvos can harm silkworm health, productivity, and genetic integrity. The study highlights the importance of responsible pesticide use in sericulture and the role of Bombyx mori as a useful bioindicator for pesticide toxicity in ecosystems.