Effect of different sulfur levels plus Thiobacillus on yield and yield components of Canola (Brassica Napus L.) cultivars in Gorgan, Iran

In an effort to determine the effect of different sulfur levels plus Thiobacillus (Thiobacillus sp.) bacteria on yield, yield components and protein content of canola cultivars, a factorial experiment was conducted in a randomized complete block design with three replications in 2014-2015. The experimental treatments consisted of three hybrid genotypes of winter canola (Hyola401, RGS003 and Gerry) and sulfur at five levels (0, 250, 500, 750 and 1000 kg ha-1, plus Thiobacillus). The results indicated that various cultivars of canola and different values of sulfur plus Thiobacillus had a significant effect on studied factors. As Hyola 401 contained the highest number of pods per plant, 1000 grain weight, grain yield and shoot dry matter. Gerry genotype also had the maximum height to the first branch and number of branches, while the largest diameter of main stem was observed in RGS003 and Gerry. Moreover, the 1000 kg S ha-1 treatment achieved maximum height to first branch and harvest index, while the highest number of pods per plant, number of branches, grain yield and shoot dry mass were found in 750 and 1000 kg S ha-1 treatments. In the interactions, the highest grain yield was observed in the interaction of Hyola401 in 1000 kg S ha-1, while the highest protein content in the interaction of Gerry cultivar was obtained in 750 and 1000 kg S ha-1. In conclusion, sulfur and thiobacillus supplementation could be lead to better crop performance and significant increment in protein level of canola seeds.