Bioefficacy of four essential oils against Callosobruchus analis (F.) (Coleoptera: Bruchidae), A seed pest of stored legumes world wide
Jyotika Brari, DR Thakur
Laboratory bioassay of the essential oils extracted from Z. armatumR. rugosaA. maritima and C. oppositifolia by hydrodistillation was carried out against the major bruchid pest C. analis to evaluate their oviposition deterrency, ovicidal activity and progeny deterrency. There was a significant difference in the number of eggs laid on treated and control and among the different treatments of essential oils. Z. armatum at 100 µl/ml allowed the bruchid to lay only 19.15±3.6 eggs as compared to 82.35±4.5 in control and proved to be most effective treatment with 76.74% oviposition deterrency. R. rugosa and A. maritima oil were found most effective in reducing the egg hatchability to 48.00±3.2 and 49.52±2.2% respectively at a lowest dose of 10 µl/ml. Egg hatching inhibition percentage increased with an increase in concentration in all the treatments. R. rugosa oil at 100 µl/ml proved to be most effective in reducing the adult emergence with 85.48% progeny deterrence followed by A. maritima showing 81.67% deterrency. All the tested essential oils revealed a wide range of bioactivities against the insect pest.