Weed management effect on density, growth parameters and yield of cowpea

Cowpea suffers badly due to weed invasion which cause wide range of yield reduction. Therefore, an experiment was planned to determine the effect of different pre- and post-emergence herbicides, stale seedbed techniques and hand weeding in cowpea (Vigna unguiculata L.) during summer season of 2019 and 2020. The average yield losses due to crop-weed competition in cowpea was estimated by 71.32%. The relative density of monocot, dicot and sedges observed in weedy plot were 55.1, 34.3 and 10.6 no./m², respectively. Plant height, branches/plant, pods/plant and seeds/pod were significantly higher under application of pendimethalin 30 EC 750 g/ha fb HW at 30 DAS, being at par with weed free (HW at 20 and 40 DAS) and pendimethalin 30 EC 750 g/ha fb imazethapyr 10 SL 60 g/ha at 30 DAS. This subsequently produced higher seed (1.37 t/ha) and stover yield (2.07 t/ha) and net return ( 65799/ha) of cowpea. Considering the labour shortage conditions and econiomics, pendimethalin 30 EC 750 g/ha PE fb imazethapyr 10 SL 60 g/ha at 30 DAS ( 64627/ha) was endorsed for weed management to produce comparable cowpea yield with highest B: C ratio (3.17).