Study oil seed and seed protein of two rapeseed(Brassica napus L.) and relations of them with oil yield and protein yield

In order to determine the effects of water deficit and different nitrogen levels on oilseed, seed protein and relations of them with oil yield and protein yield in rapeseed,two field experiments were conducted using a factorial split-plot in randomizedcomplete block design in 2005 and 2006 growing seasons at Seed and PlantImprovement Institute, karaj. In this study, two cultivars (Zarfam and Modena), threewater regimes (irrigation after 40, 60 and 80 percent depletion of soil water) and fournitrogen levels (0, 75, 150 and 225 Kg/ha) were studied that irrigation and nitrogentreatments were in main plots and cultivars were in sub plots. Results showed thatincreasing the nitrogen rate from 0 to 225 kg/ha and increasment in soil water, causedincreasing seed yield, oil yield and protein yield. In water stress condition the seed oildecreased (7.17%) but the seed protein increased (8.31%). Increasing nitrogen usedcaused to decreasing seed oil (10.08%) and increasing seed protein (25.19%). Oilyield had strong and significant correlation with seed yield and oil percent. Also,protein yield had positive and significant correlation with seed yield. In contrast thetwo varieties, Zarfam had a higher nitrogen uptake and mobilization under normalirrigation and severe water stress conditions, and also in higher and lower nitrogenconditions.