Efficacy of Three Bioinsecticide and A methomyl Insecticide Against Cotton Leafworm Larvae, Spodoptera littoralis under Controlled Semi-field Conditions at El-Behara Governorate

Document Type : Original Article

Author

Cotton Leafworm Research Department, Plant Protection Research Institute, Dokki, Giza, Egypt

Abstract

In order to evaluate the effect of time elapse and field conditions on the efficacy of three bioinsecticides and a methomyl insecticide against cotton leafworm, Spodoptera littoralis, 2nd and 4th instar larvae, a semi-field experiment was designated. The study was carried out throughout 2015 and 2016 growing seasons at El-Dakhaly village, the western side of Rashid branch, Kom Hamada Center, Beheira Governorate. Obtained results showed gradual increased mortality rates when 2nd and 4th instar larvae of S. littoralis fed on treated cotton leaves with LC50 of tested bioinsecticides until reaching the 5th day post application. Starting from the 6th day post application a gradual increased larval mortality rates were observed in both 2nd and 4th instar larvae in both growing seasons. Obtained data also showed gradual decrease in mortality rates was observed along nine days post application with LC25 of Kuik® in both 2015 and 2016 growing seasons.

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