Production potential of wheat (Triticum aestivum) as affected by varying population densities of wild oat (Avena ludoviciana)

A field experiment was conducted during 2007–08 and 2008–09 at Ludhiana, Punjab, to study the effect of varying population densities of wild oat (Avena ludoviciana) (0–250 plants/m²) on the production potential of wheat [Triticum aestivum (L.) emend. Fiori & Paol.] crop and to find out the critical population level of Avena ludoviciana in wheat crop for guiding the farmers to take proper control measures to keep the population level of this weed below economic threshold level. As the plant population density of Avena ludoviciana increased, the dry matter production, effective tillers (reduced by more than 50% in presence of 250 plants/m²) and ultimately yield of wheat decreased exponentially. Even presence of 15 plants/m² of Avena ludoviciana resulted in significant decrease (10– 14%) in grain yield. Reduction in yield was mainly caused by the reduction in effective tillers, number of grains per spike and 1,000-grain weight.