Pest succession studies in pigeonpea

摘要

Pest succession studies were conducted during kharif season of 2003 and 2004 in pigeonpea crop. Among various insect pests, termites and aphid colonised the crop during the seedling stage. Leafhopper appeared during the later vegetative stage, whereas, the gram pod borer appeared at 14 weeks after sowing (WAS), reaching its peak activity at 20 WAS. Subsequently, pod bug, pod fly and tur plume moth appeared simultaneously as single group in the crop at 15 WAS. Pod fly remained active from pod fillingtill harvesting. During the reproductive stage of the crop, incidence of thrips was noticed. Initially, it multiplied slowly and later on increased at faster rate leading to the peak level at 20 WAS, Among two predators, ladybird beetle was the first toappear and reached its maximum intensity during the peak incidence of aphid. Later on, Chrysoperla swung into action when the leafhopper colonised the crop. Thus, the activity of majority of pests was confined between 12 and 20 WAS.