Histoarchitectural alteration in midgut of Dysdercus koenigii (Fabricius) (Hemiptera: Pyrrhocoridae) treated with chlorpyrifos

Dysdercus koenigii is a species of true bug in the family Pyrrhocoridae. It is a serious pest of cotton crops. This study aimed to investigate the midgut of adult D. koenigii at the ultrastructural level using light microscopy. Insecticide chlorpyrifos of the concentration 0.0002% and 0.0008% were provided in food to adult bugs to examine the alteration from normal histology of midgut. This study indicated that midgut was highly affected after 24h post-treatment and the intensity of the histopathological effects was dependent on the concentration used. On applying insecticide, deformation in the shape of midgut was seen. Midgut gets more deformed in 0.0008% as compared to 0.0002% concentration. In midgut, epithelial layer gets detached from muscular layer and this detachment was more pronounced at higher concentration. Degeneration was observed in basement membrane. The results suggest that chlorpyrifos could be used as an effective insecticide for the control of D. koenigii.