The Use of Herbicides to Control Weeds in Soybean Crops (Glycine max L. Merrill)

An experiment was conducted at ‘The Research Farm, College of Agriculture, Tikamgarh, during the kharif season, 2016-17. The field was mainly infested with monocot weeds like Brachiaria ramosa, Commelina benghalensis, Cyperus rotundus and Echinochloa crusgalli. Dicot weeds Digera arvensis, Phyllanthus niruri and Mollugo pentaphylla were less dominant in the soybean ecosystem. The treatments comprised of pre-emergence herbicides; clomazone @ 1 kg/ha, pendimethalin @ 1 kg/ha and alachlor @ 1 kg/ha and post-emergence herbicides; imazethapyr @ 75 g/ha, imazethapyr + imazamox @ 70 g/ha, quizalofop-p-ethyl @ 50 g/ha+ chlorimuron-ethyl @ 9 g/ha,quizalofop-p-ethyl @ 50 g/ha, chlorimuron-ethyl @ 9 g/ha, two hand weeding at 20 and 40 DAS and weedy check., dry matter and weed index. It was also found superior in respect of various growth and yield attributes. The highest seed yield (825 kg/ha) and straw yield (1152 kg/ha) of soybean and maximum gross return (₹ 37,611 ha-1) and net return (₹ 23,951 ha-1) were also recorded in imazethapyr + imazamox 70 kg/ha as postemergence with highest B:C ratio of 2.75. It was also found responsible for the highest N, P and K uptake by soybean crops and the lowest uptake of these plant nutrients by weed plants.