Seasonal incidence of major insect pests of chilli crop and their correlation with abiotic factors

Abstract

A field experiment was conducted during rabi season in the year 2018 at Vegetable Research Centre, Pantnagar to study the seasonal incidence of major insect pests of chilli crop in relation to weather parameters. The results depicted the first incidence of aphids, thrips on the 43rd SMW, whitefly appeared on 45th SMW while borers (Helicoverpa armigera and Spodoptera litura) were recorded in the trial field on 1st SMW. The predators (spiders and ladybird) were reported in the field on 44th SMW. The sucking pest complex (aphids, thrips and whitefly) attained their peak on 6th SMW while the borer reached their peak densities on 7th SMW. The predator populations were maximum on 6th SMW. Aphids and thrips were positively correlated with mean temperature (r= 0.503* and r= 0.393), mean relative humidity (r= 0.218 and r= 0.251) and rainfall (r= 0.296 and r= 0.284). Borers (Helicoverpa armigera and Spodoptera litura) showed positive and significant correlation (r= 0.491* and r= 0.476*) with rainfall. Maximum temperature (r= -0.663** and r= -0.632**) and sunshine hours (r= -0.604** and r= -0.570**) had highly significant and negative influence on spiders and ladybird population.