Response of canola grain and oil yields, oil and protein contents to different levels of nitrogen and boron fertilizers in Ahwaz region

In order to investigate the effect of different levels of nitrogen and boron fertilizers on canola grain protein, oil and yield, in Ahwaz region, an experiment was conducted in 2005-2006 cropping season in Ramin Agriculture and Natural Resources University. The experimental design was a randomized complete blocks with three N rates (150, 200 and 250 kg/ha) and four B rates (0, 2.5, 5 and 10 kg/ha). All treatments were replicated four times. Result showed that with increasing nitrogen rates, grain and oil yield significantly increased. Application of boron also significantly influenced grain yield. Nitrogen × boron, on grain and oil yield was not significant. However, highest grain and oil yield was obtained from 250 and 10 Kg/ha N and B, treatment. With comparison of treatments it was observed that 200 Kg N/ha with 10 Kg B/ha produced grain and oil yield higher than 250 Kg N/ha without Boron. Grain protein and oil contents with increasing of nitrogen levels were significantly increased and decreased, respectively. But boron application had no effect on grain protein and oil contents. Results also showed that relationship between grain yield and grain oil and protein contents can be showed with a logarithmic equation. These relationships was significantly affected by nitrogen levels. With increasing of nitrogen rates, reduction of grain oil and protein contents, were slower in higher levels of grain yield. Although, effect of boron were small on this traits, but grain oil and protein contents in higher levels of grain yield was less than lower yields.