Department of Entomology, Himachal Pradesh Krishi vishvavidyalaya, Palampur-176 062, H.P. (India).
*Assistant Entomologist, HPKV, Research Sub-station, Salooni-176 320, District Chamba, Himachal Pradesh (India).
The avoidable losses caused by aphid complex comprising Lipaphis erysimi Kalt., Brevicoryne brassicae Linn. and Myzus persicae Sulzer to three different cruciferous oilseed crops, viz., Brassica campestris var. toria; B. campestris var. sarson and raya, Brassica juncea Linn. were estimated during rabi season in the field. The percentage losses were 67.61, 62.51 and 50.00 on toria (var. DK-1), sarson (var. BSH-1) and raya (var. Varuna), respectively. The losses caused by the aphid complex during the flowering stage in these crops were more, being 14.39, 9.5, and 2.08 per cent, respectively, as compared to vegetative stage. To avoid these losses, spraying of such crops with methyl demeton (25 EC) at the rate of 750 ml/ha should be done at the Initiation of flowering stage and, if required, repeated after 15 days interval.
