The effect of biological fertilizers on yield, yield components and seed oil contents of three cultivars of canola (Brassica napus L.)

Canola is the world third oil crop with 25 to 55 percent oil content (Hezbavi & Minaei، 2008). In recent years، tendency towards expansion of the acreage of canola in Iran has been increasing and for the years 2010-2011 an area of 93000 ha with a total production of 190000 tons has been reported (Ministry of Jihad of Agriculture، 2013). Application of biological fertilizers which are environmentally friendly agents have been reported to enhance yield and quality of different crops (Shoghi Kalkhoran et al.، 2012; Afrasiabi et al.، 2011). The purpose of the present study was to investigate the effects of biological fertilizers on quantitative and quality criteria of canola. For this study، a factorial arrangement based on randomized complete block design and three replicates was used. The experimental treatments were three canola cultivars namely Okapi، Zarfam and Modena which was combined with four levels of biological fertilizers: Nitroxin، Phosphat solubilizing bacteria (PSB)، Nitroxin+PSB and a control. Seeds were planted in plots of 2×3 m2. All field managements were carried out based on conventional practices. The measured criteria were plant height، number of pods per plant، 1000- seed weight، biomass yield، harvest index، oil content and yield. The results showed that in all studied criteria except 1000- seed weight there were significant differences between cultivars. Different fertilizer treatments had a significant effect on all criteria except 1000- seed weight and HI. Modena cultivar had the highest oil yield and quantitative characteristics. Composition of phosphate solubilizing bacteria+nitroxin also had the highest oil yield and quantitative characteristics. The interactions between biofertilizer treatments and cultivars in all criteria were not significant. The result of this experiment indicated the effectiveness of use of biofertilizers.