In order to investigate the effect of Nitrogen on quantitative and qualitative characteristics of spring type of forage canola in summer cultivation, this experiment was conducted in Ghazvin at 2012. This experiment was done in split plot form and with a randomized complete block design with three replications. The main factor included five levels of Nitrogen (N) :( 0, 75, 150, 225 and 300 kg\h). The sub factor included two varieties of spring type of Canola including RGS003 and SARIGOL. The impact of Nitrogen (p≤0/05) on final fresh forage and final dry forage was significant. The highest fresh forage yield was obtained from applying 300(kg/h) Nitrogen and RGS003 variety with the average of 46382.42(kg/h). The highest forage Glucosinolate content was obtained from using 300(kg/h) and SARIGOL variety with the average of 29.80(mg/g) where as the lowest forage Glucosinolate content was approached from non using of Nitrogen fertilizer and RGS003 variety with average of 12.20(mg/g). The highest protein percentage was obtained from using 300(kg/h) with average of 13.17(%). The RGS003 variety with average of 12.76(%) compared to SARIGOL variety with the average of 12.30(%) produced more protein .The highest fat percentage was obtained from using 150(kg/h) of Nitrogen with average of 2.56(%). Increasing or decreasing in Nitrogen application resulted to decreasing in forage oil percentage.
