Effect of fertility levels and weed-management practices on weed-control efficiency, yield and nutrients uptake in summer mung bean (Vigna radiata)

A field experiment was conducted in a split-plot design during the summer season (zaid) of 2016 at the Norman Borlaug Crop Research Centre, Pantnagar, Uttarakhand, to evaluate the influence of various fertility levels and weed-management practices on weeds, crop yield and nutrients uptake in summer mung bean [Vigna radiata (L.) R. Wilczek]. All fertilizer treatments showed significant effect on grain yield, while weed-control treatments significantly reduced the weed growth and nutrient removal by weeds compared with the weedy check. Among the fertilizer treatments, an application of 18 kg N + 48 kg P₂O₅ + 24 kg K₂O/ha (recommended dose of fertilizer) along with micronutrients (Zn-EDTA 0.045% + boric acid 0.1% + ammonium molybdate 0.1%) as foliar spray at 20 and 40 days after sowing (DAS) resulted in significantly higher grain yield (853 kg/ha) than rest of the treatments. However, pre-emergence application of pendimethalin (1 kg/ha) followed by 1 hand-weeding (HW) at 30 DAS significantly reduced the weed density and weed dry-matter, with highest weed-control efficiency (63.4%). This combination resulted in the highest grain yield (1,064 kg/ha) with 147% increase over the weedy check and the lowest nutrient removal by weeds, and thus proved to be the best weed-control option in summer mungbean.