Field Evaluation of Some Insecticides for Controlling Black cutworm, Agrotis ypsilon and Their Effect on Some Histological Aspects.

Document Type : Original Article

Authors

1 Plant Protection Res. Inst., ARC, Dokki, Giza.Egypt.

2 Plant Protection Res. Inst., ARC, Dokki, El Sharkia, Egypt

Abstract

Field experiments were carried out to evaluate the efficacy of certain insecticides, Lambada cyhalothrin (5% EC) as Affact power, Lambada cyhalothrin (10.6%) + Thiamethoxan (14.1%) as Anjio (24.7% SC) and Chlorantraniliprole formulated as Coragen (20% SC) belonging to different groups against Agrotis ypsilon larvae in potato crop in Egyptian governorate; El Qalyubia during two successive seasons, February 2018 and 2019 under field conditions. All the tested plots showed a highly significant reduction in Agrotis ypsilon population after 3 days post-treatment with all tested insecticides as poison baits. The reduction was higher in the second season 2019 than the first season 2018 with Coragen and Affact power. The most effective insecticides by the mean of reduction % in the two seasons were Coragen and Anjio by 92.91 and 92.26%, respectively while Affact power by 88.68%. Semi-field technique was used to study the histological changes of two sub-lethal rates 50 and 25% of these compounds on the 4th and 5th instars midgut structure post three days of treatments. The midgut structure was affected with all the treated rates of insecticides with various degrees that concluded in separation or disappearing and lysis of basement membrane which led to separate the epithelial cells from it with undistinguished shapes. The peritrophic membrane was separated or destructed and lysis led to mixing of the lumen content with lysis cells. All or some of these changes led to the loss of the midgut function, nutrition, and digestion; so they could be used in the integrated pest management control against Agrotis ypsilon

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