Influence of season and crop stage on incidence of banana pseudostem weevil, Odoiporus longicollis

Abstract

A study investigating the impact of season and crop stage on the incidence of the banana pseudostem weevil in the Mysuru region of Karnataka revealed that the pest's presence persisted throughout the year. However, two distinct peak periods of infestation were observed: one during August-September and another during March-April. The infestation levels varied from 11.50% to 41.75% regardless of the crop stage. In ratoon crops, the percentage of infestation ranged from 12.00% to 54.50%, whereas in fresh crops, it varied from 11.00% to 32.00%. Notably, the percentage of infestation in ratoon crops was observed to be higher than that in fresh crops. This trend can be attributed to the fact that the banana pseudostem weevil tends to infest crops that are more than five months old. In several fresh crop fields, the infestation levels were negligible or non-existent. The correlation study between various weather parameters and the percentage of infestation revealed consistent findings. Specifically, maximum temperature exhibited a negative correlation with the infestation percentage across all crop stages, while other weather parameters such as minimum temperature, minimum and maximum relative humidity, and rainfall showed a positive correlation with the infestation rate.