Response of Pre and Post emergence herbicide on green gram (Vigna radiata L.) and associated weeds

Abstract

A field experiment was conducted during the summer 2022 at Crop Research Centre of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut (U.P.) to study “Response of Pre and Post-emergence herbicide on Green Gram (Vigna radiata L.) and associated weeds”. The soil of the experimental field was well drained, sandy loam in texture, low in organic carbon and available nitrogen, medium in available phosphorus, potassium and slightly alkaline in reaction. Ten weed management treatments i.e. Pendimethalin (1 kg ai ha-1) at 2-3 DAS, Pendimethalin fb imezathapyr (1 kg ai fb 75g ai ha-1) at 2-3 fb 12-15 DAS, Imazthapyr (75g ai ha-1) at 12-15 DAS, Chlorimuron-ethyl (9 g ai ha-1) at 12-15 DAS, Quizalofop - ethyl + imezathapyr (50 + 75g ai ha-1) at 12-15 DAS, Imazathapyr + imazamox (70 g/ha) at 12-15 DAS, Propaquizafop + imezathapyr (50 + 75 g ai ha-1) at 12-15 DAS, Cycloxydim + imezathapyr (80+75g ai ha-1) at 12-15 DAS, Weed free and Unweeded control were tested in randomized block design with three replication. Green gram Virat was sown on 3st August, 2022 and harvested on 10th October, 2022. Recommended package of practices were adopted during crop period except treatments. The experimental field was infested with Echinochloa colonum, Cynodon dactylon and Digitaria sanguinalis among the grassy weeds, Commelina benghalensis, Amaranthus viridis and Parthenium hysterophorus among broad leaved weeds and Cyperus rotundus among the sedge as major weeds. Among the different herbicidal treatments significantly lowest population and dry weight of weeds were found in the treatment Pendimethalin fb imezathapyr (1 kg ai fb 75g ai ha-1) at 2-3 fb 12-15 DAS. Experimental results shows that all weed control practices were effective for controlling weeds in green gram and gave significantly higher grain yield over weedy check. Based on different weed control treatments, manual weeding still proved to be the efficacious to keep the plot weed free followed by Pendimethalin fb imezathapyr (1 kg ai fb 75g ai ha-1) at 2-3 fb 12-15 DAS. Highest growth parameters, yield attributes, yield and nutrient uptake of green gram was observed with weed free, which was found statistically at par with the application of Pendimethalin fb imezathapyr (1 kg ai fb 75g ai ha-1) at 2-3 fb 12-15 DAS. Among herbicidal treatments, Pendimethalin fb imezathapyr (1 kg ai fb 75g ai ha-1) at 2-3 fb 12-15 DAS was found excellent in gross return, net return and B: C ratio. Although the maximum net return was obtained in weed free treatment but non-availability of human power may be a constraint therefore chemical weed management will be a better option. Therefore, the application of Pendimethalin fb imezathapyr (1 kg ai fb 75g ai ha-1) at 2-3 fb 12-15 DAS seems better for higher productivity and profitability of green gram crop.