Estimation of losses in three different cruciferous oilseed Brassica crops due to the aphid complex in Himachal Pradesh (India).

摘要

In a field study in Himachal Pradesh, the avoidable yield losses caused by aphid complex comprising Lipaphis erysimi, Brevicoryne brassicae and Myzus persicae to three different cruciferous oilseed crops Brassica campestris var. toria, B. campestrisvar. sarson and B. juncea were estimated. The yield losses were 67.61, 62.51 and 50.00% on toria (cv. DK-1), sarson (cv. BSH-1) and B. juncea (cv. Varuna), respectively. Most of the losses occurred when the infestation was prevalent during the floweringstage. These losses were checked by the application of 750 ml/ha of methyl demeton (25 EC) at the initiation of flowering.