Effects of wheat and barley intercropping ecosystem on the prevalence of aphid (Hemiptera: Aphididae) population in canola (Brassica napus L.) crop

Abstract

For the enhancement of cultural control, the agricultural practices such as intercropping can profoundly affect the insect pest populations. Studies were undertaken to examine the effects of intercropping wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) with canola (Brassica napus L.) on the incidence of aphid (Hemiptera: Aphididae) population and related crop yield. Study observed that aphid Myzus persicae (Sulzer), was the most abundant insect pest at the experimental sites and its population differences existed between treatments. Canola intercropped with cereals supported smaller number of aphid per plant and enhanced seed yield than monoculture. Decreased aphid numbers occurred in wheat from intercropping than resulting from barley that led to similar impacts in corresponding crop yield. Increased aphid populations occurred in wheat and barley grown alone than resulting from intercropping with canola leading to similar reduction in corresponding grains yield. Studies on aphid population dynamics with reference to crop phenological stages investigated that the invasion of M. persicae was originated during flowering or pod formation stage and peak population was generally found during seed filling growth stage. Further, the ecological factors contributed variations in aphid infestation levels during crop season. Implications of these results for the control of aphid in canola using cereals or vice versa could be argued that can be suitable integrated pest management strategy in agro-ecosystem.