Preying capacity of different established predators of the aphid Lipaphis erysimi (Kalt.) infesting rapeseed-mustard crop in laboratory conditions

Experiments on the preying capability of different stages of larvae of coccinellid and syrphid flies on the mustard aphid, Lipaphis erysimi (Kalt.), were conducted in a laboratory during the winter cropping seasons of 2009-2010 and 2010-2011. Results revealed that grubs of the Coccinella septempunctata Linn. preyed the highest number of mustard aphids (average 61.42 aphids/day) followed by Syrphus confrater Wied (34.81 aphids/day), Syrphus balteatus Deg. (32.26 aphids/day) and Ischiodon scutellaris Fab. (27.76 aphids/day) during their larval span. Among the larval stages of the coccinellid and syrphid predators, it was also analysed that the last juvenile stage of the predators was proved the mightiest devourer against the aphid L. erysimi. These predators could be used effectively for the management of L. erysimi on rapeseed-mustard crop.