Assessment of Herbicide and Sorgaab-Based Integrated Weed Management in Mungbean (Vigna radiata (L.) Wilczek) under Arid Agro-Climatic Conditions

Abstract

Mungbean [Mungbean] is an important pulse crop widely cultivated in the arid and semi-arid regions of India because of its high nutritional value and ability to improve soil fertility through biological nitrogen fixation. However, its productivity in Rajasthan remains low due to severe weed infestation during the early growth stages. Weeds compete with the crop for nutrients, moisture, light, and space, especially during the critical crop-weed competition period of 15–30 days after sowing (DAS), causing significant yield losses. Manual weeding is effective but labour-intensive and costly, while excessive herbicide use may create environmental and resistance problems. Therefore, integrated weed management (IWM) involving herbicides, hand weeding, and allelopathic approaches offers a sustainable solution. Sorghum water extract (sorgaab), containing allelochemicals such as phenolics and flavonoids, has shown potential in suppressing weeds. The present study was conducted to evaluate different integrated weed management practices in mungbean under western Rajasthan conditions. A field experiment was conducted during Kharif 2024 at the Instructional Farm, College of Agriculture, Jodhpur, Rajasthan. The experiment was laid out in a Randomized Block Design with ten treatments replicated three times. Treatments included combinations of herbicides, hand weeding, and sorgaab application. The mungbean variety GM-4 was sown following recommended agronomic practices. Observations on weed density, weed dry matter accumulation, weed control efficiency (WCE), weed index, and economics were recorded at different crop growth stages. The results revealed that integrated weed management practices significantly reduced weed density and weed dry matter accumulation compared to the weedy check. Among the dominant weeds, Digera arvensis, Dactyloctenium aegyptium, and Cyperus rotundus were effectively controlled by herbicide-based integrated treatments. Application of fluazifop-p-butyl 11.1% + fomesafen 11.1% SL @ 220 g ha⁻¹ at 20 DAS followed by hand weeding at 30 DAS (T₆) proved most effective and recorded the lowest weed density and weed dry matter accumulation at all growth stages. This treatment also achieved the highest weed control efficiency (97.11% at harvest) and the lowest weed index (6.04%), indicating minimum yield loss due to weeds. Treatments involving sodium-acifluorfen + clodinafop-propargyl and imazethapyr + imazamox integrated with hand weeding also performed effectively and remained statistically comparable. Sorgaab alone was comparatively less effective; however, its integration with hand weeding or herbicides improved weed suppression considerably. Economic analysis showed that the highest benefit-cost ratio (3.66) was obtained with fluazifop-p-butyl + fomesafen followed by hand weeding, followed by sodium-acifluorfen + clodinafop-propargyl + hand weeding (3.58). Thus, integrated use of herbicides with hand weeding proved to be the most effective and economical weed management strategy for mungbean cultivation under western Rajasthan conditions.