Impact of Herbicides and Microbial Inoculants on Weed Infestation in Soybean (Glycine max L.)

Abstract

A field experiment was conducted during the Kharif season of 2024–25 at the Research Farm, R. A. K. College of Agriculture, Sehore, Madhya Pradesh, to evaluate the impact of herbicides and microbial inoculants on weed dynamics in soybean. The experiment was laid out in a Split Plot Design with five main plot treatments of herbicides and four sub-plot treatments of microbial strains, replicated thrice. The predominant weed species were Echinochloa colona, Cyperus rotundas, Commelina benghalensis, and Digera arvensis. Results revealed that hand weeding at 20 and 40 DAS recorded the lowest weed density and maximum weed control efficiency (95.42%), followed closely by Diclosulam @ 26 g a.i. ha⁻¹ applied pre-emergence followed by Propaquizafop 2.5% + Imazethapyr 3.75% @ 2.0 L ha⁻¹ at 15–20 DAS. Among microbial treatments, combined inoculation of Bradyrhizobium daqingense + Bacillus aryabhattii reduced weed proliferation by improving crop competitiveness. The study concludes that integrated herbicide and microbial management strategies are effective in minimizing weed infestation, reducing competition stress, and promoting sustainable soybean cultivation.