Efficacy of some botanical extracts against Callosobruchus maculatus in cowpea seeds and an evaluation of their toxicity


S.I. AhmedA and A.A. GazzyB

A Pesticides Department, Faculty of Agriculture, Kafr El-Sheikh University, 33516, Egypt.

B Biology Department, Faculty of Science, Kafr El-Sheikh University, 33516, Egypt.


Abstract

Extracts of seven plant species were tested under laboratory conditions for their ability to protect cowpea seeds against the insect Callosobruchus maculatus. The insect was reared and tested on whole cowpea seeds with respect to the adult’s mortality, hatchability of laid eggs and emergence. Gas chromatography-mass spectrometry (GC–MS) analysis was carried to identify the chemical components of the most effective plant extracts against C. maculatus. Furthermore, the safety of the most effective plant extracts was evaluated with respect to biochemical and histological changes in rats.

The results revealed that Euonymus japonicus and Cassia fistula extracts were the most effective against C. maculatus with respect to insect mortality and progeny relative to the control. The GCMS analysis of these extracts showed the presence of different bioactive compounds. These extracts also showed low toxicity on treated rats. The results suggest that these extracts may be a safe alternative to insecticides.

Keywords: Stored products, malathion, cowpea.

 

Plant Protection Quarterly (2011) 26 (4) 130-5.