Vol. 4, Issue 1, Part B (2022)

Cowpea beetle, Callosobruchus maculates (Fabricius) (Coleoptera: Chrysomelidae: Bruchidae), is the most notorious store grain pest. Pulses constitute the major source of protein in most of the developing countries including India. The stored grain pests are difficult to control because of chemical insecticides if used causes health hazards to us. Adult C. maculates were exposed to 4, 8, 12 and 16ml concentration of extract/Kg grains of mung bean (Phaseolus aureus (Roxb) and were homogenized separately.
After the treatment with acetone extract the mortality was recorded at 4ml concentration of extract per kg grains of mung bean, was observed i.e. 50%. The number of eggs laid were 115±5.00, grains infected were 109.33±3.21 and adult emerged were 98±3.00 respectively while at above 12 ml concentration of extract per kg grains of mung bean, the adult mortality was high i.e. 100%. There was no infestation and emergence of adults recorded. In chloroform and ethanol extracts of Argemone mexicana L seed the adult mortality was high 100%, there was no infestation and emergence of adult recorded at all concentrations per kg grain of mung bean. Methanol extract had very poor toxic effect and low inhibitory effect on the reproductive activity and hence, large number of the adults emerged out, they can damage the P. aureus grains severely in the forthcoming generations.
As the concentration increases, significant reduction in adult emergence takes place. Seed extract of A. mexicana L. in acetone, chloroform and ethanol solvent shows highest mortality, no infestation and no adult emergence as compared with control while based on these findings, it can be used to control the infestation of stored grain pest C. maculatus F.