Population dynamics of Helicoverpa armigera in pearl millet

Abstract

:Population dynamics of Helicoverpa armigera in pearl millet was studied during Kharif 2015 at Instructional Farm, Junagadh Agricultural University, Junagadh. The study revealed that the pest incidence commenced from seventh week after sowing in variety GHB-558 and was found active from August to September in the crop. The pest population increased in the last week of August and reaching to a peak level of 1.56 larvae per ear head. Then it was decreased (0.82 larvae/ear head) during the first week of September and remained active steady upto second week of September. Among the different parameters, maximum temperature and mean bright sunshine hours showed positive correlation whereas minimum temperature, morning relative humidity showed negative correlation with population of this pest but did not reached at significant level. However, the correlation between the pest population and evening relative humidity was significant and negative. Rainfall exhibited a non-significant and negative correlation with the pest population.