SEASONAL INCIDENCE AND INFLUENCE OF WEATHER FACTORS ON POPULATION DYNAMICS OF GRAM POD BORER, HELICOVERPA ARMIGERA HUB. IN GRAM ECOSYSTEM

摘要

A study was conducted to assess the population dynamics of Gram pod borer, Helicoverpa armigera (Hub.) during the two rabiseason 2010-11 and 2011-12 under field condition. It revealed that occurrence of Helicoverpa armigera was less severe in 14th (0.4) and 1" (0.9) during 2010-lland 2011-12 and more severe during 48th (5.6) and ll* (6.2 mean larva! population/meter length) standard week. The larval population density varied from 0.4-6.2 mean population per meter length. From the present investigation, it is evident that the Helicoverpa population on gram had a positive correlation with maximum temperature (0.5202 during 2010-11 and 0.6339 during 2011-12) and negative correlation with relative humidity (-0.3536 during 2010-11 and -0.4151 during 2011-12) and rain fall (-0.14966 and -0.3343 during 2010-11 and 2011-12).