Economics, Herbicides, Turfgrass, Weed management
A field experiment was conducted to test the efficacy of different weed control treatments on control of turfgrass weeds in the established lawn of Bermuda grass ‘Selection No. 1’ at Punjab Agricultural University, Ludhiana during winter and summer seasons of 2021. The experiment was laid out in a randomized complete block design with 15 treatments i.e., post-emergence application (PoE) of isoproturon 0.937 kg/ha, mesosulfuron + iodosulfuron 0.014 kg/ha, clodinafop + metribuzin 0.216 kg/ha, 2,4-D amine 0.50 kg/ha, bispyribac-sodium 0.025 kg/ha, metribuzin 0.120 kg/ha, metsulfuron 0.005 kg/ha, carfentrazone-ethyl 0.020 kg/ha, metsulfuron + carfentrazone-ethyl 0.025 kg/ha, metsulfuron-methyl + chlorimuron-ethyl 0.004 kg/ha, ethoxysulfuron 0.018 kg/ha, halosulfuron 0.050 kg/ha, atrazine 1.0 kg/ha, hand weeding twice at 15 days interval and weedy check. The PoE of isoproturon 0.937 kg/ha, mesosulfuron + iodosulfuron 0.014 kg/ha, clodinafop + metribuzin 0.216 kg/ha, bispyribac-sodium 0.025 kg/ha, metribuzin 0.120 kg/ha and ethoxysulfuron 0.018 kg/ha provided complete control of Poa annua, a winter season weed, which was at par with hand weeding twice, whereas, in summer season, clodinafop + metribuzin 0.216 kg/ha PoE reduced the density and biomass of Digitaria sanguinalis and Dactyloctenium aegyptium. Bispyribac-sodium 0.025 kg/ha was found effective against Dicanthium annulatum. Metsulfuron + carfentrazone-ethyl 0.025 kg/ha PoE provided complete control of broad-leaved weeds, viz. Gnaphalium purpureum, Oxalis corniculata, Desmodium triflorum, Coronopus didymus in winter season and Boerhavia diffusa and Alysicarpus vaginalis in summer season. Halosulfuron 0.050 kg/ha PoE effectively controlled Cyperus rotundus upto 45 days after spray (DAS) during winter season. Metsulfuron + carfentrazone-ethyl 0.025 kg/ha PoE recorded highest weed control efficiency (WCE) (72.9 %) during winter, whereas in summer clodinafop + metribuzin 0.216 kg/ha PoE recorded highest WCE. Sward height and dry biomass of turfgrass were found negatively correlated with the weed biomass in both of seasons. Phyto-toxicity was observed with clodinafop + metribuzin (0.216 kg/ha) PoE, however, the grass recovered after 35 DAS in winter season.