Department of Entomology and Agril. Zoology, Tirhut College of Agriculture, Dholi, Muzaffarpur-843121, Bihar, (India).
1A part of the approved Ph.D. thesis submitted by senior author to the Rajendra Agricultural University, Pusa, Samastipur-848 125, Bihar, (India).
Field studies on population build-up and relative abundance of major pod borers viz., Maruca testulalis Geyer., Melanagromyza obtusa Mall., Apion clavipes Gerst, and Helicoverpa armigera Hb. on pre-rabi season pigeonpea cv. Sharad, were carried out in two crop seasons. The crop, throughout March, experienced the maximum biotic pressure due to the composite larval population of the various pod-borers. Among these borers, M. obtusa predominated numerically as well as functionally in both the years of under study, with its peak population (15.60 larvae/plant) in the last week of March, when the crop approached near maturity.
