تاثير ازتوباكتر كروكوكوم و برادي ريزوبيوم ژاپونيكوم بر ويژگي هاي بذر سويا حاصل از شرايط كم آبي

Effect of Azotobacter chroococcum and Bradyrhizobium japonicum on soybean produced under water deficit conditions

In order to study the effect of Azotobacter chroococcum and Bradyrhizobium japonicum on soybean [Glycine max (L.) Merr] cultivar seed characteristics produced under water stress, a factorial test was conducted in form of completely randomized design with four replications. Treatments were water stress [Irrigation after 50 mm (normal irrigation), 100 mm (mild stress), and 150 mm (severe stress) evaporation from pan of class A], Cultivar [Manokin, SRFXT3, Williams] and inoculation [Bradyrhizobium japonicum, Bradyrhizobium japonicum co-inoculated with Azotobacter chroococcum, control]. The result showed that stress has significant effect on time, speed and percent of germination .Seedling inoculated with Bradyrhizobium japonicum, had higher length compared to seeding not inoculated. The dry weight of Seedling grown from seeds produced under mild stress was 10% higher the one that in normal irrigation. Bradyrhizobium japonicum, co-inoculated with Azotobacter chroococcum, increased mean time of germination and root dry weight. Seeds produced under mild stress as compared to normal irrigation, had further seedling and stem length. Therefore, bacteria couldnʹt compensate severe stress effects and just increased seed characteristics of mild stress condition.