Weed control in mungbean (Vigna radiata L.) with residue mulch, pre- and post-emergence herbicides

Abstract

Mungbean in the rice-wheat cropping system of northwest India faces severe competition from complex weed flora, resulting in reduced yield. Therefore, there is a need for effective and sustainable weed control measures in mungbean to enhance its productivity. Field experiments were conducted in 2022 and 2023 to evaluate the effectiveness of 15 weed control treatments in mungbean. The study assessed the impact of residue mulch and various pre-emergence (PRE) and post-emergence (POST) herbicides on mungbean. In both years, mungbean yield was improved with imazethapyr at 100 g ai ha⁻¹ (by 74–78 %) and pendimethalin at 750 g ai ha⁻¹ (by 69–74 %) applied as pre-emergence treatments, as well as with propaquizafop at 100 g ai ha⁻¹ (by 68–76 %) and quizalofop-ethyl at 50 g ai ha⁻¹ (by 63–64 %) applied as POST treatments, achieving over 75 % weed control compared with the nontreated control. A ready mixture of clodinafop + sodium acifluorfen (165 + 80 g ai ha⁻¹) applied POST resulted in 95 % and 96 % higher yields in 2022 and 2023, respectively, compared with the nontreated control by providing excellent weed control (>90 %). Wheat residue mulch (6 t ha⁻¹) increased mungbean yield by 59 % and 73 % in 2022 and 2023, respectively, compared with the nontreated control, by effectively reducing weed biomass. Pre-emergence herbicide (flumioxazin 250 g ai ha⁻¹, imazethapyr 100 g ai ha⁻¹, pendimethalin 750 g ai ha⁻¹, and pyroxasulfone 127 g ai ha⁻¹) treatments supplemented with wheat straw mulch did not provide an additional advantage for yield when compared to these herbicide treatments without mulch. Halosulfuron at 67 g ai ha⁻¹ applied POST initially caused the crop's toxicity, later recovered and thus resulted in improved yield by 27 % and 42 % in 2022 and 2023, respectively, compared with the nontreated control. These results suggest that pre-emergence herbicides such as imazethapyr and pendimethalin, and POST herbicides such as clodinafop + sodium acifluorfen, propaquizafop, and quizalofop-ethyl can be used in mungbean as a herbicide rotation program for sustainable weed control. Further, these results suggest that residue mulch can be used for effective weed control in the organic production of mungbean. Future research could focus on integrating these herbicide strategies with cultural techniques such as row spacing, seeding rate, etc., to further enhance weed management efficiency and crop productivity.