Effect of mycorrhizal fungi and rhizobium bacterial on qualitative and quantitative traits of soybean in response to drought stress

In order to investigate the effect of drought stress and inoculation with mycorrhizal fungi and rhizobium bacteria on quality and quantity of soybean yield, an experiment was conducted as a split-plot factorial in a RCBD with three replications at research farm of Agricultural Highschool of Urmia during 2017 cropping season. Main plot was drought stress including optimum irrigation, moderate drought stress and severe drought stress and sub plots were mycorrhizal fungi in three levels (without mycorrhiza and inoculation with Glomus mosseae and G. intraradices) and Rhizobium japonicum in two levels (without inoculation and inoculation with R. japonicum). In response to moderate drought stress, protein percentage increased but increasing severity of drought stress reduced protein and oil percent. Irrigation along with inoculation with mycorhizal fungi specially G. mosseae enhanced number of seeds per plant, protein percentage and protein yield. Under three irrigation conditions, inoculation with bacteria compared to non-inoculation led to increase seed yield, oil yield and protein yield. Inoculation with bacteria and mycorhizal fungi increased seed yield and oil yield. Study of correlation coefficient showed that there was a positive and significant correlation between seed yield with 1000-seed weight, number of seeds per plant, oil and protein yield. According to the results of this research, using mycorrhiza G. mosseae and inoculation with R. japonicum can have a positive effect on the quantitative and qualitative traits of soybeans.