Abstract:Germination energy, germination rate, germination index and other eight identification indices of seventeen varieties of naked oat were measured under drought stress simulated with 20% PEG-6000. According to the relative value of eleven identification indices as evaluation indices, drought resistance of oat varieties was evaluated comprehensively with the method of weighted membership function on the basis of the principal component analysis. The role that identification indices play in evaluation of drought resistance among different varieties was compared. The results showed that vigor index (VI) was the most susceptible to drought stress, and the closest to the comprehensive evaluation value of drought resistance and could be used for rapid and preliminary identification of drought resistance of naked oat germplasm at germination stage. An optimal regression model for the comprehensive evaluation of drought resistance was established and could be use to effectively predict the drought resistance of naked oat varieties at germination period through measuring germination rate, average germination velocity, length of the longest primary root, total length of primary roots, coleoptile length and vigor index of seed. Three varieties, namely N-C33Ⅳ-45-16, grosse and Gaoqian Sihao with stronger resistance to drought stress were identified through comparing the comprehensive value of drought resistance among tested varieties, and could be used to cultivation and breeding for dry conditions.