Occurrence of Aphis odinae van der Goot and its natural enemies in cashew

Abstract

Aphis odinae, a polyphagous aphid, was found infesting cashew trees in Puttur, Karnataka. The damage symptoms caused by these aphids, their seasonality and their natural enemies were recorded in this study. The incidence of aphids was observed from August and April every year. The aphids infest emerging flushes, inflorescences and developing nuts. Severe damage to inflorescence resulted in the drying of flowers and the premature fall of tiny nuts. However, medium-sized cashew nuts usually mature or tolerate the aphid infestation without any damage. The size and germination percentage of aphid infested matured nuts, and healthy nuts indicated not much variation. Under field conditions, four species of coccinellids and three species of syrphids were found predating on different stages of aphids and brought their population under control within a short period. The species of ants associated with aphids were also documented. Considering the incidence and severity of the damage, it is a minor pest of cashew in the study area.