Azadeh Haddad sabzevar - Microbiology Department, Faculty of Sciences, Islamic Azad University- Qom Branch
A. Shirvani - Department of Plant Protection, Faculty of Agriculture, Shahid Bahonar University of Kerman
Mohammad Reza Zolfaghari - Microbiology Department, Faculty of Sciences, Islamic Azad University- Qom Branch

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.