Latent Effects Of Emamectin Benzoate Formulations On Spodoptera Littoralis Boisd. (Lepidoptera: Noctuidae)

Document Type : Original Article

Authors

Department of Economic Entomology and Pesticides, Faculty of Agriculture, Cairo University, 12613 Giza, Egypt.

Abstract

Chemical control is used as a rapid and reliable method for insect control, but there is an ongoing need to
replace older conventional insecticides with new insecticides to maintain efficacy and environmental
protection. Emamectin benzoate is a bioinsecticide insecticide, which is used widely for the control of
lepidopteran insects. In the present study, the latent effects of four emamectin benzoate formulations
including; Absoluota 5% microencapsulated emulsion (ME), Emi-Mainar 5.7% Water Dispersible granule
(WG), Camaro 5% Emulsifiable concentrate (EC), and Proclaim 5% Water Soluble Granules (SG). Second
instar larvae of Spodoptera littoralis that survived after exposure to LC10, or LC50 values of each formulation
were maintained in the laboratory for larval and pupal development, reproductive activity, and oxidative stress
enzymes assessed. Results exhibited that Emi-Mainar was more toxic (LC50= 0.007 μg/ml) than Absoluota
and Proclaim (0.015 and 0.019 μg/ml). The toxicity of Camaro was comparable with the other formulations.
The activity of superoxide dismutase (SOD) was significantly high when 2nd instar larvae were treated with
LC50 concentrations of Emi-Mainar and Camaro formulations and significantly low with LC50 values of
Absoluota, Proclaim and LC10 concentrations of Emi-Mainar, Camaro, and Absoluota formulations. While no
effect was observed in the catalase enzyme (CAT) activity in all tested larvae with LC10 and LC50 of all
formulations. Moreover, all tested formulations increased the development times of larval and pupal stages.
The results suggest that Emi-Mainar formulation may have the largest impact on S. littoralis populations
compared to other tested form of emamectin benzoate formulations.

Keywords