Bio-efficacy of different post-emergence herbicides in mungbean

Weeds result in a significant yield loss in mungbean (Vigna radiata [L.] R. Wilczek). However, post-emergence (POST) herbicides are limited in mungbean for broad-spectrum weed control. Therefore, we evaluated the efficacies of different herbicides in mungbean to find a suitable broad-spectrum POST herbicide. Nine herbicides, weed-free check, and unweeded control treatments were tested in a randomised block design with three replications for two consecutive years. Among the tested herbicides, clodinafop-propargyl + sodium-acifluorfen 122.5 g a.i. ha(-1) applied at 15 days after sowing (DAS) reduced the broad-leaved weed dry weight at 35 DAS and harvest by 55.8% and by 58.6% (p < 0.05) compared with the unweeded control respectively. Notably, it minimised the total weed dry weight by 23.1%-30.3% compared with the recommended herbicide pendimethalin 1 kg a.i. ha(-1) - quizalopfop-p-ethyl 100 g a.i. ha(-1) (p <= 0.05). Clodinafop-propargyl + sodium-acifluorfen had higher weed control index (58.2% at 35 DAS and 62.1% at harvest) over the remaining tested herbicides. Unweeded controls resulted in 51% yield loss compared with the clodinafop-propargyl + sodium-acifluorfen that did not differ from pendimethalin - quizalofop-p-ethyl for seed yield of mungbean. Decreasing order of meaherbicide efficacy comprised the weed-free check clodinafop-propargyl + sodium-acifluorfen and pendimethalin - quizalofop-p-ethyl, imazethapyr + imazamox, tembotrione, topramezone for grain yield. Application of clodinafop-propargyl + sodium-acifluorfen led to the greatest increase in soil microbial biomass carbon, indicating higher levels of soil biological and rhizospheric activity. We suggest that clodinafop-propargyl + sodium acifluorfen is a suitable broad-spectrum option for weed management of mungbean.