Population dynamics of gram pod borer (Helicoverpa armigera Hübner) on chickpeas

The present investigation was carried out at research farm of Tirhut College of Agriculture, Dholi, Muzaffarpur, Bihar during Rabi 2017-18. The larval population was initially recorded in 7th standard week (third week of February) (2.33 larva/plant) with a peak in 13th standard week (2nd week of April) (5.33 larva/plant). Mean larval population of Helicoverpa armigera on chickpea variety KPG-59 was found positively correlated with maximum temperature (0.495), whereas minimum temperature and relative humidity (7 Hrs and 14 Hrs) shows negative and non-significant correlation (-0.055), (-0.553), respectively. Correlation between rainfall and larval population was found negative and significant (-0.666). However, all the weather parameters together contributed 80.7 percent towards Helicoverpa armigera larval population.