Identification methods of salt tolerance of alfalfa seedling stage

Alfalfa (Medicago sativa) is halophyte species, and breeding its salttolerant varieties benefits the development and utilization of saline land. However, simple, direct, convenient and efficient method for identifying salt tolerance of alfalfa varieties was not well defined at present. The germination test, saline nutrient solution and the natural brine methods was used to determine the salt tolerance of five alfalfa varieties at seeding stage and seedling stage. The tolerance index of five alfalfa varieties was calculated by the relative germination rate, the average relative germination potential and the average number of relative root length. Based on the tolerance index, the salt tolerance of five varieties of alfalfa was evaluated in this study. This study showed that the nutrient solution method was optimal to identify the salt tolerance of alfalfa vatieties.