Incidence of chewing pests in okra in north eastern hill region of India

Abstract

An experiment was conducted to study the incidence of chewing insect pest populations in okra ecosystem in north eastern hill region of India. The results revealed that a peak population of Nodostoma spp. was noticed during July (56.46 per 5 plants). Maximum relative humidity had a significant positive correlation with Nodostoma spp. (r = 0.672*). When there was an abrupt fall in minimum and maximum relative humidity coupled with increase in maximum and minimum temperature, a build-up in Nodostoma spp. population was recorded. A peak population of Mylabris pustulata recorded during July (3.81 per 5 plants). The highest population build-up of M. pustulata was observed an increase in minimum and maximum temperature and a decrease in minimum and maximum relative humidity. The highest population of Alcidodes affaber was observed during July (2.57 per 5 plants). A peak population of A. affaber was recorded as soon as maximum and minimum temperatures crossed 24 and 32°C, respectively and minimum and maximum relative humidity was below 80 and 95%, respectively. Correlation between chewing pests indicated that Nodostoma spp. recorded positive significant correlation with M. pustulata (r = 0.285) and A. affaber (r = 0.533). Similarly, M. pustulata showed strong positive significant correlation with A. affaber (r = 0.581).