Impact of multi mix herbicide on growth and weed indices in irrigated groundnut (Arachis hypogaea L.)

Abstract

Food and nutritional security for the country India depends on the agriculture sector. Groundnut is an important food legume cum oilseed crop and weed infestation is the major problem causing yield reduction. Therefore, the field experiment study was conducted during the winter season of 2022 at Central farm, Agriculture College and Research Institute in Madurai to evaluate the newer multi-mix herbicide combinations and find out the appropriate weed management practices for yield enhancement and weed suppression in irrigated groundnut (Arachis hypogaea L.). The experiment consisted of twelve treatments (T₁ to T₁₂) laid out in a randomized complete block design. Among the weed flora, almost two third of the weed infestation was documented as broad-leaved weeds (51%), followed by grassy weeds (36%) and less infestation by sedges (13%) in groundnut at the experimental site. Application of pre-emergence alone and post-emergence alone does not suppress the weed infestation efficiently. For that, this study focused on using multi-mixed herbicides along with hand weeding to determine herbicide's efficacy on weed control and growth parameters. Among the weed control methods, weed-free check (T₁₂) increased the growth parameters viz., Plant height (65.3 cm), Leaf Area Index (4.34) and Dry matter accumulation (5536 kg ha^-1) and higher weed control efficiency (99.2%). Among the herbicidal treatments, pre emergence application of pendimethalin + imazethapyr (ready mix) followed by hand weeding at 40 days after sowing (T₇) gave significantly (P=0.05) higher results in growth components of groundnut and weed suppression compared to other herbicidal treatments.