This research in order to evaluate the effect of different levels of irrigation regime on yield and yield components of soybean in Urmia region at the Urmia agricultural high school Research during 2012 using split plot based on a randomized complete block design with three replications. Drought treatments (optimum irrigation 60 mm, moderate drought stress 110 mm and severe drought stress 160 mm evaporation by evaporation pan Class A) were included in main plots and the Cultivars (Clark, Williams and Onion) were allocated in subplots. The results of variance analysis showed that the effect of drought stress on seed yield, oil and protein content was significant (P<0.01), so that the maximum and minimum oil and protein value obtained by optimum irrigation and severe drought stress conditions, respectively. However, for relative water content and leaf chlorophyll, there was no significant difference. Severe drought stress reduced the grain yield by 63 and 45% compared to the optimum irrigation and moderate stress conditions, respectively. In optimum irrigation and severe drought stress conditions, the highest seed yield, oil yield and protein yield, obtained by Onion genotype. A Clark genotype in comparison with other cultivars had the minimum seed yield, in severe drought stress conditions.

In order to study the effects of different levels of sulfur along with Thiobacillus and zinc on qualitative and quantitative growth of canola cv RGS003, a factorial experiment was conducted based on an RCBD with three replications at the Agricultural Research Station of Gonbad in 2013. The first factor was the application of sulfur with Thiobacillus at four levels, i.e. without sulfur and Thiobacillus (S0), 500 kg sulfur ha^-1 + 10 kg Thiobacillus ha^-1 (S1), 1000 kg sulfur ha^-1 + 20 kg Thiobacillus ha^-1 (S2) and 2000 kg sulfur ha^-1 + 40 kg Thiobacillus ha^-1 (S2). The second factor consisted of two levels of zinc: without zinc (control) and 20 kg zinc sulfate ha^-1. The results showed that all traits studied were significantly affected by sulfur with the exception of pod length. The effect of zinc was significant at 0.01 probability level of biological yield, seed yield, harvest index, straw yield, oil percent and oil yield. With an increase in application of sulfur mixed with Thiobacillus up to 1000 kg sulfur ha^-1 + 20 kg Thiobacillus ha^-1 (S2), all yield components increased except oil percent, but their further increase resulted in reduction of seed yield and yield components of canola cv RGS003. With the exception of oil content, the other traits studied were not affected by the interaction of sulfur by zinc.