Effect of wild oat (Avena fatua L.) population and nitrogen levels on some agronomic traits of spring wheat (Triticum aestivum L.)

A field experiment was conducted to determine the effect of wild oat (Avena fatua) densities on wheat (Triticum aestivum) yield, its components and protein content under varying nitrogen regimes, at the Agricultural Research Farm, North West Frontier Province Agricultural University, Peshawar, Pakistan, during winter 2004-5. The experiment comprised 3 nitrogen levels (75, 100, and 125 kg ha-1) assigned to main plots and 5 wild oat densities (0, 10, 20, 30, and 40 plants m-2) kept in sub-plots. The data were recorded on some agronomic and physiological parameters of wheat and wild oats. The statistical analyses of the data exhibited nonsignificant differences for nitrogen levels in all the parameters studied, while oat density and the interaction of density with nitrogen levels were significant for all the parameters studied. Less than 1 wild oat plant m-2 inflicted a 1% reduction in wheat yield, while a 30% reduction in yield was predicted with the infestation of 15, 17, and 16 plants m-2 under 75, 100, and 125 N kg ha-1 fertiliser regimes. We also discovered a wild oat density related reduction in grain protein content, which is a cause for further alarm. About 16 wild oat plants m-2 reduced protein content by 1%, which is alarming for countries with vegetable-based diets, like Pakistan. © TÜBİTAK.