Evaluation of nitrogen fixation ability of common bean (Phaseolus vulgaris L.) cultivars with three types of inoculants which contain different strains of Rhizobium phaseoli

The ability of nitrogen fixation in three cultivars of common bean (Phaseolus vulgaris L.) with three types of inoculants which contain different strains of Rhizobium phaseoli was evaluated in Khoramdareh, Zanjan province, Iran in 006. Treatments were an investigation with three types of biological fertilizers including: Rhizobean super plus, Super nitro plus and Azetobacter, with two treatments: N75 (use of 75 kg nitrogen/ha) and control (without seed inoculation and fertilizer) and three bean cultivars including: COS6 (spotted bean), Keshavarze (white) and Naz (red bean). The experiment was conducted as factorial in randomized complete block design with three replications. The results showed significant differences in seed yield, nitrogen percent per plant, seed protein percentage, number and weight of nodules (48 day after emergence), seed and dry matter yield among seeds inoculated and non-inoculated. Rhizobean and N75 caused the most seed yield, total dry matter and nitrogen and protein percentage. Results showed that Rhizobean super plus was more effective on common bean, as compared with Super nitro plus and Azotobacter. This investigation showed that for achievement satisfying yield and sustainable agriculture, all of industrial biofertilizers should be used as complementary materials with mineral fertilizers.