Efficiency of certain miscible oils and chlorpyriphos methyl insecticide against the soft scale insect, Kilifia acuminata Signoret (Homoptera: Coccidae) and their toxicities on rats

Abstract

The toxicity and efficacy of using three miscible oils; cabl-2, citrole and bio-dux and a chemical insecticide (chlorpyrifos-methyl) were studied against a soft scale insect, Kilifia acuminata (Signoret) infesting mango trees. The sub-chronic toxicity of tested chemicals on white albino rats was also studied. Considering the general mean number of K. acuminata stages after 3 months post spraying, chlorpyrifos methyl and capl-2 were the most efficient compounds followed by citrol and bio-dux in descending order. Chlorpyrifos-methyl was the most effective treatment for all months after spraying, the mean reduction percentage being 94.10, 91.63 and 92.00% while it gave the highest toxic effect after three months; 90.27, 87.84 and 89.73% reduction in infestation on pre-adult, adult and gravid female stages, respectively. Results also indicate that the general mean percent reduction in K. acuminata infestation were 82.62, 86.67, 78.87 and 89.28% in treated trees by citrole, cabl-2, bio-dux and chlorpyrifos-methyl, respectively. Citrole, bio-dux, cabl-2 and chlorpyrifos-methyl caused significant increase in WBCs counts, ALT and AST activities of treated rats after 15 and 30 days from treatment comparison with control. Changes occurring in the creatinine concentration showed a significant increase in rats treated with the tested chemicals 30 days from treatment, except in the case of bio-dux oil, while there were no significant changes after 15 days in rats treated with tested oils. On the contrary, tested chemicals caused a significant decrease in RBCs count and hemogobin values after 15 and 30 days form treatment, except in rats treated with bio-dux oil. Hemoglobin content showed no significant changes over the same periods.