Sinorhizobium Isolated from Soil of Qom and Suburbsin Order to Promote Growth of Alfalfa Plants Traditionally and to Maintain the Indigenous Strains of Beneficial Bacteria in Soil

Continuous cultivation of diffrent plants in agricultural lands, reduces soil fertilityand will face the plants, with deficiencies ofusefull nutrients.The lack of nitrogenthat it is important element for plants,has a negative effect on plant growthand eventually will lead to reduced efficiency [4].Alfalfa(Medicago sativa)isaperennialforageandan important source ofprotein forfeedingthequadruped[7].Alfalfacan increasesoilorganicmatter, andthe storage ofnitrogeninthesoilsurface[3].Sinorhizobiummeliloti is anaerobic gram-negativebacteriumfromtherhizospherecaninfectroots ofMedicagospecies, and will expand symbiosis[6].In this study Sinorhizobium bacteria wereisolated from soil of Qom and suburbsin order to promote growth of alfalfa plants traditionally and to maintain theindigenous strains of beneficial bacteria in soil.