Legume Research

Pulse beetle, Callosobruchus maculatus is the most serious pests in stored legumes in majority of tropical countries. Attention has been given to the possible use of plant products or plant dry powders as promising alternatives to synthetic insecticides in controlling insect pests of stored products. Present study seven plant species evaluated for their bio activity to pulse beetle.

Laboratory studies were conducted at Department of Crop Protection, Agricultural College and Research Institute, Valavachanur, Thiruvannamalai district to study the effect of various plant powders tested against, Callosobruchus maculatus (F.) infesting stored black gram. The experiments were conducted two sets, first experiment (insecticidal action) and second on ovipoistion, egg hatchability, adult emergence and seed weight loss.

The Piper nigrum 2 per cent seed powder was found to be significantly the best compared to other treatments and caused 100 per cent mortality at one day after treatment. At seven days after treatment, Azadirachta indica (87.77%), Coccinia indica (80.50%), Abutilon indicum (73.50%), Acalypa indica (73.33%) and whereas untreated control recorded only 36.66 per cent mortality was recorded. Piper nigrum was significantly superior than all other treatments in complete inhibiting the oviposition, adult emergence and seed weight loss showed in P. nigrum 2 per cent seed powder treated black gram seeds as compared to untreated control higher numbers eggs laid (107 eggs), adult beetle emergence (90 adults) and seeds weight loss (34.26%) at 30 DAT, (39.22%) at 45 DAT and (45.28%) at 60 DAT. Different concentration of P. nigrum seed powder experiment results concluded that all the four doses (0.50, 1.00, 1.50 and 2.00%) highly effective against C. macultus viz., mortality, oviposition adult emergence and seed weight losses.