Biological effects on silkworm larvae fed by mulberry leaves treated with carbendazim fungicide

The biological effects on silkworm larvae fed on mulberry leaves contaminated with 0.5 and 1 mg/ml carbendazim were analyzed in different periods. The fungicide was sprayed on trees with 0, 1, 2, 4 and 8 days intervals before the first feeding of second instar larvae. Carbendazim decreased the larval weight and the highest reduction was 4.5% decrease compared to control. One mg/ml of fungicide used immediately after treatment caused a significant decrease in female cocoon characteristics such as cocoon weight, pupa weight and shell weight by 8.4, 8.5 and 7.8, respectively. The rate of hatching had also decreased in some treatments. Economical traits of male insects and the number of laid eggs by females were not affected. In total, the mean of cocoon shell percentage in both sexes did not have any difference with control. Feeding from the leaves contaminated with carbendazim residue did not have significant effects on larval mortality and utilization of the leaves sprayed by this fungicide two days after application is recommended.