Effect of weed management practices on weed control efficiency, yield, nutrient uptake and economics of summer maize (Zea mays) under humid tropic conditions ​

Abstract

Weed management is the most challenging component of summer maize cultivation. Weeds that are not controlled compete for light and the crop’s nutrient and water resources, and yield losses may be up to 70% of the potential yield. The critical time for weed control in maize is between crop emergence and canopy closure. Therefore, a field experiment was conducted during summer, 2019 at the N. M. College of Agriculture Farm, Navsari Agricultural University, Gujarat, India to find effective weed management practice in summer maize cultivation. The treatments included various weed management strategies where pre and post emergence herbicides were either sprayed or integrated with hand weeding. The results revealed significantly higher grain and straw yield (6473 and 8041 kg/ha, respectively) with weed free, which was statistically at par with pendimethalin (CS) @ 1.5 kg/ha as pre-emergence (PE) + 1 hand weeding (HW) at 30 days after sowing (DAS). Among the weedicide treatments, minimum weed population at harvest, least dry weight of weeds, lowest weed index, highest weed control efficiency and maximum benefit cost ratio was recorded in pendimethalin (CS) @ 1.5 kg/ha as PE + 1 HW at 30 DAS) which was followed by treatment T5 (Pendimethalin EC @ 1.0 kg/ ha as PE +1 HW at 30 DAS). Maximum nitrogen, phosphorus and potassium content in grain and straw was recorded in weed free plots which was statistically at par with treatment T6 where Pendimethalin (CS) @ 1.5 kg/ha was applied as pre-emergence and integrated with one hand weeding thirty days after sowing.