Littlcsecd canarygrass (Phalaris minor Retz.) is a problematic weed of wheat under irrigated rice-wheat cropping system of lndo-Gangetic plains (IGP) of India. Due to its morphological similarity with wheat, herbicides are the best-suited method for its control. However, continuous use of same herbicide along with monocropping leads to development of multiple-herbicide resistance. To tackle this problem, an experiment was conducted at CCS Haryana Agricultural University, Hisar during 2016-17 and 2019-20 to find out the suitable herbicide combinations for management of resistance Phalaris minor, its regression and correlation studies with wheat. The finding revealed that increase in weed density and dry weight displayed a strong negative linear relationship with grain yield. Linear regression equation represented that increase in every one unit of density and dry weight of P. minor led to reduction in wheat yield by 0.027 and 0.0102 times, respectively. Among the herbicidal treatments, sequential application of pendimethalin + pyroxasulfone (tank-mix, TM) fb mesosulfuron + iodosulfuron (ready-mix, RM) (1500 + 102 g/ha) prc-enicrgence, (PE) Jb 14.4 g/ha post-emergence, (PoE) or pendimethalin + metribuzin (I'M) fb mesosulfuron + iodosulfuron (RM) (1000 + 175 g/ha) PE Jb 14.4 g/ha PoE led to significantly control of P. minor, broad-leaved weeds (BLWs) and total weeds. This resulted in better crop growth, higher yield attributes, 37.6-51.9% higher grain yield and 80-81% higher net return as compared to unwecded control. However, PE or PoE herbicide applied alone recorded poor efficacy towards P. minor and other weeds and resulted in poor yield. Correlation studies indicated strong positive association of grain yield with visual weed control, crop dryweight and its height and negative association with weed density and dry weight. Therefore, for effective management of resistant P. minor along with other weed flora, herbicide combination with its sequential application is cf nrime importance for optimum yield in wheat.
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