Population dynamics of insect pests on short duration pigeon pea in relation to weather parameters

Population dynamics of insect pests on short duration pigeon pea was studied in relation with weather parameters during kharif 2016 and 2017. Spotted pod borer, Maruca vitrata (F.) and blister beetle, Mylabris pustulata Thunberg were observed to be major pests in Delhi environment during both the years while, low incidence of other pests viz., gram pod borer, Helicoverpa armigera (Hubner) andpod bug, Clavigralla gibbosa Spinola were also recorded. Spotted pod borer population peaked during 41st standard meteorological week. Blister beetle incidence commenced during 36 th standard meteorological week and peaked during 37th standard meteorological week. Maximum temperature of 1-lag week was found to have non-significant positive correlation with gram pod borer (r= 0.64) and spotted pod borer (r = 0.52) larval population. The built-up of pod bug population had highest significant negative correlation with minimum temperature (r=-0.82) of current week and also with relative humidity (r = -0.93) of current week.