Comparison of rapeseed and mustard agronomical traits response to nitrogen amounts under after cropping

In order to investigate of nitrogen amounts and harvest time effect on qualitative and quantitative traits of canola and mustard forage under after cropping, a split plot experiment as base of randomized complete design with 3 replications was conducted in Qazvin, during summer and autumn 2012. Experimental factors included nitrogen (N1: recommended nitrogen rate, N2: 25% more than recommended nitrogen rate and N3: 50% more than recommended nitrogen rate) as main plot and two species (S1: rapeseed and S2: mustard) as sub plot were considered. Investigations showed that the grain yield was increased with elevation of nitrogen fertilizer consumption. So that the highest grain yield was gained from 300 kg/ha with mean of 1103 kg/ha and the lowest value also was belonged to 200 kg/ha with mean of 601.6 kg/ha. Comparison of two species also revealed that rapeseed with mean of 1116 kg/ha was superior to rapeseed with mean of 916.3 kg/ha, significantly.