Author(s)

Roxelle Ethienne Ferreira Munhoz, Thaís Souto Bignotto, Naiara Climas Pereira, Cláudia Regina das Neves Saez, Rafaela Bespalhuk, Verônica Aureliana Fassina, Graziele Milani Pessini, Mayarha Patrícia Dequigiovanni Baggio, Lucinéia de Fátima Chasko Ribeiro, Rose Meire Costa Brancalhão, Shunsuke Mizuno, Willian Shigeaki Aita, Maria Aparecida Fernandez

Departamento de Biotecnologia, Genética e Biologia Celular, Universidade Estadual de Maringá, Maringá, Brasil;.
Fia??o de Seda Bratac S. A. Bastos, S?o Paulo, Brasil.
Universidade Estadual do Oeste do Paraná, Cascavel, Brasil.

The silkworm Bombyx mori feeds exclusively on mulberry leaves and is highly sensitive to pesticides in general. Although mulberry plantations are free of agrochemicals, pesticide drift can occur. Chlorantraniliprole, a novel insecticide of the anthranilic diamides class, has been used to control pests in field crops. In this study, we investigated the biological effects of different concentrations of chlorantraniliprole on B. mori silkworm commercial Brazilian hybrids. To evaluate the toxicity of chlorantraniliprole, bioassays were carried out and data on the lethal concentrations, symptomatology, morphology and variables of silk production were collected. Results indicated that B. mori is extremely sensitive to chlorantraniliprole, even in low concentrations. The highest silkworm mortality rates were observed in the two highest chlorantraniliprole concentrations, 0.2 and 0.1 ppm. Although lower chlorantraniliprole concentrations did not cause death of all the silkworm larvae, various symptoms of toxicity were observed: feeding cessation, regurgitation, late development and incomplete ecdysis. Such symptoms reflect the morphological changes we observed in the midgut epithelium, which affected nutrient uptake and metabolism, and even the production of cocoons. Exposed larvae also produced thin-shelled cocoons, which constitutes a serious economic problem because this type of cocoon is not useful for the silk industry. The results provided herein confirm the toxicity of chlorantraniliprole in silkworm larvae. Therefore, we strongly suggest that, competent authorities of the National Health Surveillance Agency, in pesticide management should take measures to reduce or eliminate the use of chlorantraniliprole in areas nearest to silkworm cultivation.

Silkworm, Pesticide Drift; Mortality; Symptomatology; Chlorantraniliprole

Munhoz, R. , Bignotto, T. , Pereira, N. , Saez, C. , Bespalhuk, R. , Fassina, V. , Pessini, G. , Baggio, M. , Ribeiro, L. , Brancalhão, R. , Mizuno, S. , Aita, W. and Fernandez, M. (2013) Evaluation of the toxic effect of insecticide chlorantraniliprole on the silkworm Bombyx mori (Lepidoptera: Bombycidae). Open Journal of Animal Sciences, 3, 343-353. doi: 10.4236/ojas.2013.34051.