Effect of nitrogen levels and cultivation arrangements on yield and yield components of wheat, Triticum aestivum L.

In order to optimizing nitrogen fertilizer and cultivation arrangements to increase wheat (cv. Dabira) yield in Khuzestan province of Iran, an experiment was conducted in Dezful Agricultural Research Center as randomized complete block design (RCBD) based on split plot with three replications during 2008-2009 growing season. The main factor consisted of nitrogen at four levels (0, 75, 150 and 225 kg ha -1 ) and seven cultivation arrangements including two and three rows cultivation on 40, 50 and 60 cm furrows apart with each other and one flat cultivation treatment with 20 cm rows apart were allocated to subplots. Results showed significant differences among studied cultivation arrangements in yield, 1000 seeds weight, number of ears per square metre, seed number in an ear and biomass. Also, there was significant difference among nitrogen levels for grain yield, 1000 seeds weight, biomass, number of ears in square metre and number of seeds in an ear. Regarding to the studied quantitative and qualitative characteristics, the highest yield was observed in treatments with two and three cultivation rows on 60 cm furrows apart. The yield was also increased by increasing nitrogen fertilizer level up to 150 kg ha -1 . The treatment of two cultivation rows on 60 cm furrows apart with 150 kg ha -1 nitrogen application was recognized as the best treatment with 5860 kg ha -1 yield and 12.47 percent protein.