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提高水稻种子耐低温和低氧发芽能力是解决直播稻全苗问题的有效途径.本研究以23份用于构建染色体单片段代换系文库的水稻亲本为材料, 在低温和低氧逆境下进行发芽试验, 考察了15个种子活力相关的指标, 通过多重比较分析、变异分析、主成分分析和相关性分析等对供试品种进行了综合评价.结果表明, 供试水稻品种的各项指标表现出广泛的变异, 变异系数为0.100.64, 变异系数最大的是15℃第7天的发芽率.通过主成分分析, 低温和低氧下分别提取到3个和2个主成分, 累计贡献率分别为86.3％和91.8％, 两者之间无显著相关性.低温下综合排名前3的品种为W5 (籽恢100) 、W22 (Khazar) 和W2 (Amol 3), 低氧下综合排名前3的品种为W10 (南洋占) 、W22和W13 (江西丝苗) .据散点图分析, 23个品种被分为4类, 6个低氧抗性低温感性型, 6个低氧抗性低温抗性型, 7个低氧感性低温抗性型, 4个为低氧感性低温感性型, 其中W22在低温和低氧条件下综合表现优良.本研究结果可以为直播稻新品种选育提供参考.“,”Improving seed germinability under low temperature and hypoxic conditions is an effective way to solve the full stand problem of direct seeding rice. In this study, 23 rice cultivars which had been used to construct the library of chromosome single segment substitution lines (SSSLs) in our lab were used as the material. Fifteen indexes associated with seed vigor were investigated after germination under low temperature and hypoxic conditions, and comprehensive assessments of the tested varieties were carried out by multiple comparison analysis, coefficient variation analysis, principle component analysis and correlation coefficient analysis. The results showed that the indexes of the tested rice varieties displayed a large variation, which ranged from 0. 10 to0. 64, and the largest value was the germination rate at 7 d under 15℃. Principal component analysis indicated that three and two principle components were extracted at low temperature and hypoxic condition, respectively, and the cumulative contribution percentage were 86. 3％ and 91. 8％, respectively. In addition, no significant correlation was observed between the two traits. Comprehensive ranking data demonstrated that W5 (Zihui 100), W22 (Khazar) and W2 (Amol 3) were the top three cultivars at low temperature, and W10 (Nanyangzhan), W22 and W13 (Jiangxisimiao) were the top three cultivars under hypoxic condition. Furthermore, according to the scatter diagram, the 23 cultivars were divided into 4 groups, including six anoxia resistance and low temperature sensitive ones, six anoxia resistance and low temperature resistance ones, seven anoxia sensitive and low temperature resistance ones and four anoxia sensitive and low temperature sensitive ones, in which W22 showed a superior performance both at low temperature and hypoxic conditions. These results could provide reference for breeding new direct seeding rice varieties.