Effects of Sinorhizobium melliloti . on quality traits of alfalfa varieties (Medicago sativa L.).

In order to study the effects of Sinorhizobium melliloti sp. on some quality characteristics of alfalfa forage, a factorial experiment on the basis of completely randomized design with 3 replications and 2 factors (variety and Sinorhizobium  strains) were carried out in Research institute of Forests and Rangelands of Iran from 2004 to 2005. Seed Of alfalfa varieties (Sanandaj, Oormieh, Blochestan and Khorasan) after sterilization were sown in medium plastic pots which were filled with sterilized quartzite sand. They were inoculated with Sinorhizobium melliloti sp. (Sanandaj, Rasht, Booshehr & control) solution and then  irrigation were continued with Hoagland soluble nutrition during the trial. Forage of varieties was dried and grinded by an electrical mill. A number of quality attributes such as crude protein, digestibility, soluble carbohydrates, fiber, ADF (fiber +cellulose), NDF (fiber +cellulose + hemicelluloses) and Ash of the varieties were measured using NIR (Near Infrared Reflectance spectroscopy). Analysis of collected data showed that Sinorhizobium melliloti sp., alfalfa varieties and interaction between Sinorhizobium melliloti sp., and alfalfa varieties were very significant on all of the traits. Mean Comparison of traits indicated that effect of Sinorhizobium melliloti sp. is severely better than control and also there were variation among strains. Alfalfa varieties were also various for all examined characteristics. Interaction effects of Sanandaj and Oormieh varieties with Sanandaj, Oormieh and Rasht on vital quality traits similar to Dry matter yield (dry forage), proteins, carbohydrates and digestibility were high and positive in comparison to others. It is concluded that using proper S. stains will increase not only dry matter yields but also benefit qualities of forage. Correlations between all studied attributes were determined and various relations and significant effects between them were confirmed.