Assessing the Yield and Growth Characteristics of Alfalfa Ecotypes in Soil Salinity Condition by Inoculation of Sinorhizobium Meliloti Salt Resistant Strains

This experiment was conducted in a split plot design in order to evaluate the effect of three ecotypes of alfalfa inoculated with Sinorhizobium meliloti strains resistant to salinity on yield and yield components in the East Azarbaigan agricultural research and natural resources center during the years 2011-2014. Three strains of Sinorhizobium meliloti were the main factor that selected based on the in-vitro salt tolerance testing and greenhouse evaluation. Three ecotypes of alfalfa including Garayonje, Hamedani and Malekkandy were subploted. Selected strains of rhizobium inoculated with three ecotypes of alfalfa'seed and cultivated in a soil with EC= 7.3 dS.m-1 and their effects were investigated on the number of stem per square meter, plant height and fresh and dry matter yield. The results showed that, interaction between rhizobia strains and alfalfa ecotypes was meaningful on the number of stem per square meter, fresh and dry forage yield. The highest number of stems per square meter (377) achieved with non inoculated Malekkandy ecotype. The highest dry matter achieved by Hamadani ecotype that inoculated with the strain No. 7 and Malekkandy ecotype inoculated with strains No. 10 and 5, that these strains produced forage 5.52, 5.05 and 5.02 tons per hectare, respectively. The results show that rhizobium strains that have well symbiosis with alfalfa ecotype may have better plant growth and increase feed production, maintaining soil fertility and achieve sustainability in agriculture in areas with salinity strsses