Effect of weed management options and nitrogen scheduling on weed dynamics and yield of wheat (Triticum aestivum) under Central Plain Zone of Uttar Pradesh

A field experiment was conducted during the winter (rabi) seasons of 2014–2015 and 2015–16 at Kanpur, Uttar Pradesh, to study the effect of weed-management options and nitrogen scheduling on weed dynamics and yield of wheat (Triticum aestivum L.). Common infesting weeds which appeared in wheat field were Phalaris minor Retz. and Cynodon dactylon (L.) Pers. among grasses, and Chenopodium album L., Anagallis arvensis L., Melilotus alba Medik. and Convolvulus arvensis L. as broad-leaf weeds. Moreover, among sedges, only 1 species, Cyperus rotundus L. was observed. Among the weed-management options, mesosulfuron-methyl + Iodosulfuron-methyl sodium (400 g/ha) with higher dose of nitrogen (150 kg N/ha) applied in 3 spilt applications [50% as basal + 25% at crown-root initation (CRI) + 25% at flowering] proved significantly superior in minimizing the density (33%) and biomass of weeds (34%) at 60 days after sowing (DAS). The former treatment increased the leaf-area index (LAI) and SPAD values that elevated the production of wheat grain yield. Among time of nitrogen application, 3 splits (50% as basal + 25% at CRI + 25% at flowering) enhanced the nutrient-uptake efficiency (27.4%) and total nutri ent uptake (40.2%) by crop than 3 equal splits at sowing (basal), CRI and flowering. Higher dose of nitrogen (150 kg N/ha) resulted in higher yield (15.7%) and nutrient uptake (13.4%) than its lower dose. Thus, application of ready-mixed post-emergence herbicides, i.e. mesosulfuron + iodosulfuron (400 g/ha) with higher dose of nitrogen (150 kg N/ha) applied 50% as basal and 25% top-dressed at CRI and 25% at flowering was most effective with re spect to weed-suppression, yield and economics of wheat.