Herbicide mixtures for weed control in dual purpose tall wheat and pendimethalin residue in wheat fodder and soil

Weeds are the biological constraints to increase wheat productivity in Asia. A field experiment was conducted during the Rabi seasons of 2015–16 and 2016–17 to evaluate the efficacy of pendimethalin, pinoxaden, metsulfuron, sulfosulfuron, clodinafop under sole, mixture and their sequential application against control of mixed weed flora in dual purpose wheat at area of farm CCS HAU Hisar (Haryana). The season-long growth of weeds reduced wheat yield up to 55.4 and 59.3% during 2015–16 and 2016–17, respectively. Before cutting of wheat for fodder, among herbicidal treatments, pre-emergence (PE) application of pendimethalin 1500 g/ha significantly reduced grassy (P minor) and broad-leaf weeds dry weight at 25 and 55 days after sowing (DAS) during both the years. After cutting, weed dry weight at 85, 115 DAS and at harvest was significantly reduced under sequential application of pendimethalin 1500 g/ha fb pinoxaden + metsulfuron (50 + 4) at 2 week after cutting (WAC) at 55 DAS, pendimethalin 1500 g/ha fb sulfosulfuron + metsulfuron (30 + 2) at 2 WAC and pendimethalin 1500 g/ha fb clodinafop + metsulfuron (60 + 4) at 2 WAC as compared to alone application of post-emergence (PoE). Among herbicidal treatments, significantly higher weed control efficiency, plant height, total tillers, grain yield and B:C ratio was observed under sequential application of herbicides than alone application of herbicides during both the years of study. Wheat fodder could be used safely for livestock as no residue was reported.