Evaluation of promising herbicide combinations for weed management in rajmash (Phaseolus vulgaris L.) under dry temperate conditions of Himachal Pradesh.

Alachlor at 1.0 kg ha−1+ pendimenthalin 1.0 kg ha−1, alachlor at 1.0 kg ha−1+ pendimethalin at 0.75 kg ha−1 and alachlor at 0.75 kg ha−1+ pendimethalin at 1.0 kg ha−1 were the most effective herbicide combinations in controlling weeds (Digitaria sanguinalis, Polygollum alarum and Gallillsoga parvijlora). Their effectiveness was similar to hand weeding twice in increasing pods plant−1, seeds pod−1, 1000-seed weight and seed and haulm yields. None of the herbicides alone or in combination controlled Equisetum spp. Alachlor at 1.50 kg ha−1 was not effective against broad-leaved weeds. Lowest control costs (Rs. 1291 ha−1) and highest marginal benefit: cost ratio (MBCR) were obtained due to alachlor at 1.50 kg ha−1. The different herbicide combinations evaluated recorded 3–4 times higher MBCR over the farmer's practice of hand weeding twice.