Field experiments were conducted during the winters of 1986–87 and 1987–88 at Haryana Agricultural University, Hisar, India to classify the ability of winter wheat cultivars to compete with wild oat. Wild oat reduced winter wheat grain yield by 17 to 62% depending upon cultivar. WH-147 and HD-2285 were the most competitive cultivars. Winter wheat dry matter accumulation and grain yield were negatively correlated with wild oat dry matter. A high number of tillers, particularly in HD-2009, WH-291, and S-308, did not always translate into grain yield advantage in wild oat-infested plots. Wheat height and dry matter accumulation per unit area during early crop growth were better characters than number of tillers for predicting the competitive ability of wheat cultivars to wild oat.

Field experiments were conducted during the winters of 1987–88 and 1988–89 at Haryana Agricultural University, Hisar, India to evaluate the response of winter wild oat to sowing date and isoproturon application time in wheat. In another experiment, the effect of sowing time on emergence and growth of winter wild oat and wheat sown separately was studied. The treatments that provided more than 75% control of winter wild oat were: isoproturon at 0.75 kg ha−1applied at the 2-leaf stage of winter wild oat; isoproturon 1 kg ha−1applied at the 4-leaf stage of winter wild oat in the November 30 planting; and isoproturon 0.50 kg ha−1applied at the 1- to 2-leaf stage of winter wild oat in the December 20 sowing. Isoproturon did not provide more than 50% control of winter wild oat in the November 10 sowing. Mortality of winter wild oat increased from 38 to 72 to 87% in November 10, November 30, and December 20 sowings, respectively. Mortality of winter wild oat was similar in November 30 and December 20 sowings but higher grain yield was recorded in November 30 sowing. Due to vigorous growth of winter wild oat in the November 10 sowing, isoproturon did not provide good control. December 20 sowing favored wheat growth due to lower density and late emergence of winter wild oat but reduction in wheat grain yield was greater. When averaged over isoproturon treatments, the grain yield of wheat was 4607, 5297, and 4457 kg ha−1in the November 10, November 30, and December 20 sowings, respectively.

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Field experiments were done during winter seasons of 1988-89 and 1989-90 at Haryana Agricultural University, Hisar, India. Wild oat (Avena ludoviciana) was effectively controlled at 20 and 30 d.a.s. with 0.25 to 0.35 kg/ha tralkoxydim. The average reduction of wild oat population by 0.30 and 0.35 kg/ha tralkoxydim was 73.5 and 85.4%. Significantly better efficacy of tralkoxydim was obtained with spraying than broadcasting it with urea or sand at both the stages of application. An increase in the concentration of tralkoxydim enhanced control of wild oat. On an average of application times and methods, tralkoxydim at 0.25 kg/ha gave poor wheat yields. Tralkoxydim application at 30 d.a.s. produced significantly better crop yields than its earlier application.