Evaluation on drought resistance of different alfalfa cultivars at seedling stage and comparison of the evaluating methods

As the methods of the drought resistance evaluation of alfalfa (Medicago spp.) in the home and abroad were nonuniform, two experiments on evaluations (with two different water stress) of drought resistance of 133 different alfalfa varieties collected from China or abroad were conducted and the methods of two different water stress were compared and modified in the study. The results of drought resistance of alfalfa base on two variables, which were the symptom index of drought response （average score index, ASI） and the survival rate after rewatering, were analyzed by using the SAS software. The results of this study indicated that 15 of 133 alfalfa varieties showed strong drought resistance and 11 varieties had the weakest drought resistance steadily; there was no significant difference (P0.05) between the two evaluation results; and the germination index of alfalfa showed a significant negative correlation with drought resistance in the first time (P0.01) and in the second (P0.05) evaluation, respectively.