Efficacy of herbicides in wheat (Triticum aestivum) with special reference to wild oat (Avena sterillis ludoviciana) in vertisols

A field experiment was conducted during winter season of 2004–05 and 2005–06 at Jabalpur to assess the efficacy of clodinafop-propargyl, sulfosulfuron and isoproturron as post-emergence in wheat (Triticum aestivum L. emend. Fiori & Paol.). Clodinafop @ 60 g/ha significantly reduced the density and dry matter of wild oat (Avena stereillis ssp. ludoviciana Dur.), but could not combat the problem of broad-leaved weeds, viz., Medicago hispida Gaertn., Lathyrus aphaca L., Chenopodium album L. and Vicia sativa L. Sulfosulfuron 25 g/ha provided effective control of both wild oat and broad-leaved weeds. Isoproturon 1,000 g/ha did not cause significant reduction in he population and dry matter of wild oat, but significantly reduced the problem of broad-leaved weeds. Infestation of weed throughout the crop-growth period caused 48.8% reduction in grain yield of wheat. Higher yield attributes and maximum grain yield (47.6 q/ha) of wheat were recorded from two hand-weedings at 30 and 60 days after sowing (DAS). Amongst herbicidal treatments, application of sulfosulfuron 25 g/ha (43.6 q/ha), being on a par with that of clodinafop 60 g/ha (41.5 q/ha), 120 g/ha (43.4 q/ha) and 240 g/ha (44.5 q/ha), significantly increased the grain yield of wheat and recorded the maximum net return (Rs 11,940/ha).