Evaluation of different plant leaf extracts against mustard aphid [Lipaphis erysimi (Kalt.)] in rapeseed field

Abstract

Rapeseed is highly vulnerable to attack by various insect pests. The use of botanicals for control of insect pests is an eco-friendly practice, more compatible with the environmental components, and non-hazardous to human beings. This experiment was conducted to evaluate the effects of different plant leaf extracts against Mustard aphid (Lipaphis erysimi Kalt.) from November 2016 to March 2017 at research field of Institute of Agriculture and Animal Science, Lamjung Campus, Lamjung, Nepal. Five different plant leaf extracts derived from Neem, Bakaino, Hattibar, Khirro, and Bojho, along with Cypermethrin 10% EC@ 1.5 ml/L of water; and control (without treatment) were evaluated against Mustard aphids. The experiment was conducted in a randomized complete block design with three replications. Morang-2 variety of Rapeseed was planted in the field and the Rapeseed plant was sprayed with prepared plant leaf extracts on 30 days after sowing (DAS), 45 DAS and 60 DAS, and aphid number was counted after 5, 10 and 15 days of each spray from 10 cm apical shoot. The results showed that the application of Cypermethrin 10% EC @ @ 1.5 ml/L of water significantly reduced the aphid population followed by the Complete mixture and the mixture without Khirro. The highest grain yield (1436.75 kg/ha) was found in Complete mixture treated plots. It was concluded that all these plant leaf extracts showed insecticidal properties against aphid in rapeseed crops and successfully be integrated as a part of Integrated Pest Management.