Evaluation of Some Environmentally Safe Cemicals Against Spodoptera littoralis

Document Type : Original Article

Authors

1 Central Laboratory of Pesticides, Sabahia, Alexandria, A.R.C.

2 Pesticide Chemistry Dept., Fac. of Agrie., Alex., Univ.

Abstract

Toxicity effect of Dipel-2X, and three insect growth regulators IGRs: Diflubenzuron; Spiromesifen and Pyriproxyfen, were determined against 2nd larval instar of Spodoptera littoralis. The results showed that Diflubenzuron was the most potent toxicity followed by Spiromesifen; Pyriproxyfen, and Dipel-2X. The effect of LC50 of the tested IGRs on the in vivo inhibition of chitinase from Spodoptera littoralis was assayed. The interaction effect of Dipel-2X with IGRs was investigated. Results proved that pretreated of Dipel-2X with IGRs caused more toxicity effect than single treatment. The sensitivity of chitinase activity to the three tested IGRs was measured by the I50 values. The I50 values of Diflubenzuron; Spiromesifen and Pyriproxyfenon Lab strain larval chitinase are 0.54, 0.60 and 0.73µM respectively. While the I50 values are 0.60, 0.72 and 0.81µM respectively against Field strain. The results proved that chitinase was sensitive to the IGRs. Generally, Dipel-2X pretreated with IGRs will produce a new trend so as increase toxicity of the bioinsecticide, enhance the role of beneficial insects. The results of the present study may add some forward steps to use bioinsecticide as alternative to conventional insecticides especially against this insect. So, the tested compounds can be involved in important steps necessary for successful IPM programmes applied against S. littoralis.

Files

Share

How to cite

Statistics