Changes in detoxifying enzymes and carbohydrate metabolism associated with spinetoram in two field-collected strains of Spodoptera littoralis (Biosd.)

Fahmy, Nedal M.; Dahi, Hassan F.

doi:10.21608/eajbsf.2009.17549

Changes in detoxifying enzymes and carbohydrate metabolism associated with spinetoram in two field-collected strains of Spodoptera littoralis (Biosd.)

Document Type : Original Article

Authors

Plant Protect. Res. Instit, Agric. Res. Center, Dokki, Giza, Egypt

10.21608/eajbsf.2009.17549

Abstract

This study was conducted to investigate the biochemical defensive mechanisms in larvae of S. littoralis (Biosd.) (Lepidoptera: Noctuidae) collected from cotton fields in two Egyptian Governorates (Kalyobia and Behira), sprayed with spinetoram as well as its impact effect upon carbohydrate metabolism. The role played of spinetoramon different major defensive enzymes like glutathione S-transferases (GSTs) , non specific esterases and acetylcholinesterase(AChE) was discussed. It seems that these enzymes are not greatly involved in the detoxifying process of spinetoram except a marked over production of AChE reached up to 18.7% as well as the concentration of its substrate, ACh with an increase reached up to 42.8%. Spinetoram had also a prominent effect upon carbohydrate metabolism as in glycogen content which was decreased by 34.9%, LDH also was inhibited to 55.7% while trehalase had an elevated activity by 22.8%.In general, Behira Governorate was more affected and more sensitive to spinetoram rather than Kalyobia Governorate. The present work is an introductory study to understand the outline of the mechanism of this bioinsecticide as well as the resistance mechanisms may arise in the future.

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