Interactive Effects of Nitrogen and Row Spacing on Growth and Yield of Cotton Varieties

Response of different cultivars of cotton namely Sahel, N200 and Shirpan539 to different levels of row spacing 40 cmx 20 cm and 80 cm x 20 cm and 0, 75, 150 and 225 kg ha-1 nitrogen fertilizer was studied at Gharakhil Agricultural research Station, North of Iran in 2010. Different row spacing influenced height and number of boll and different nitrogen levels significantly influenced yield and yield components of cotton. Application of 150 kg.ha-1 nitrogen fertilizer produced maximum yield, number of boll and maturity coefficient as compared to another nitrogen rates. In level of 225 kg.ha-1 nitrogen fertilizer we observed maximum height, number of node, weight of boll and number of sympodial branch as compared to the another nitrogen rates. The varieties N200 and Sahel provided maximum yield as compared to Shirpan539.