Impact of diverse weed management strategies on soil microbial population dynamics in maize

Field experiment was conducted at Eastern block farm, Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore during 2018-19 and 2019-20 to evaluate different weed management practices on soil microbial dynamics in maize. Experiment was laid out in randomized completely block design with three replications and ten treatments comprised of pre emergence atrazine fb (followed by) hand weeding at 20 DAS, pre emergence atrazine fb power weeder at 20 DAS, pre emergence atrazine at + pendimethalin at (tank mix), pre emergence atrazine + pendimethalin (tank mix) fb hand weeding at 20 DAS, early post emergence topramezone at 20 DAS, pre emergence atrazine fb early post emergence topramezone at 20 DAS, early post emergence tembotrione at 20 DAS, pre emergence atrazine fb early post emergence tembotrione at 20 DAS, hand weeding twice at 20 and 45 DAS and control. Maize was raised during kharif season of 2018 and 2019 followed by the residual crop of sunflower in rabi season of 2018-19 and 2019-20. The crops were raised under irrigated conditions. The results shown that microbial population was significantly lower in pre emergence atrazine fb either early post emergence topramezone at 20 DAS or early post emergence tembotrione at 20 DAS from 3 DAS to 60 DAS, later the microflora started increasing, but it was lesser than control. Unweeded control did not affect the soil microflora from initial to harvest stage of the maize crop.