The Effect of Biofertilizers on Some Quantitative and Qualitative Characteristics of Vetch Maragheh (Vicia sp.) under Rainfed and Supplementary Irrigation

This factorial experiment was done as a complete randomized block design with three replications at Urmia University in two years (2016 and 2017). Experimental treatments included once supplemental irrigation and dry farming as the first factor and application of biofertilizers in eight levels, Control (non-application of fertilizer), Mycorrhizal fungus (Rhizophagus intraradices), Azotobacter, Thiobacillus, Azotobacter+mycorrhiza (R. intraradices), Thiobacillus+mycorrhiza (R. intraradices), Azotobacter+ Thiobacillus, Azotobacter+Thiobacillus+Mycorrhizal fungus (R. intraradices)} were the second factor. The results showed that supplementary irrigation increased the number of pods per plant, seed phosphorus content and leaf relative humidity. The high percentage of potassium and protein were obtained in farming condition. Also, the number of pods per plant, the percentage of phosphorus, potassium and protein content of seeds and leaf relative humidity increased significantly due to the application of biological fertilizers. Thus, the combined application of mycorrhizal + Azotobacter treatment increased the number of pods per plant, the percentage of phosphorus, potassium and protein of seeds and content of leaf relative humidity by 15.55%, 34.25%, 20.22%, and 17.04%, respectively, as compared to the Control. Maximum colonization percentage (63.45%), biological yield (4986.5 kg.ha-1), grain yield (1873.29 kg.ha-1) and protein yield (503 kg.ha-1) were obtained under supplementary irrigation and combined application mycorrhizal fungus and Azotobacter. Therefore, according to the findings of this research, the combined use of biological fertilizers to increase yield and maintain long-term production in an Agroforestry system under rain-fed conditions can be desirable for sustainable agriculture.