中国水稻微核心种质不同生育时期耐冷性鉴定及其相关分析

以204份中国水稻微核心种质为试验材料，进行了水稻发芽期、芽期、幼苗期、孕穗期等耐冷性鉴定及其相关性分析。结果表明，水稻各生育时期耐冷性在籼粳亚种间、各种质之间存在明显的差异。粳稻种质的耐冷性明显强于籼稻种质，但籼稻种质中也存在耐冷性较强的种质。高阳淀稻大红芒、肥东塘稻、木樨球、卫国、兴国、山酒谷、中花8号等粳稻种质和包选21号、红米三担白、寸谷糯、红谷等籼稻种质在水稻各生育时期均表现较强的耐冷性，在水稻耐冷性育种及耐冷基因发掘研究中应加以利用。自然低温和冷水胁迫下水稻结实率与低温下发芽率呈显著或极显著正相关，而与死苗率呈显著负相关，即低温下发芽期耐冷性和芽期耐冷性强的水稻种质一般表现为较强的孕穗期耐冷性。认为低温下发芽率和芽期低温处理后的死苗率可以作为孕穗期耐冷性早期鉴定的间接指标。

Evaluation of Cold Tolerance at Different Growing Period for Mini Core Collection of Rice( Oryza stiva L.)in China

The evaluation of cold tolerance at the germination period,the budbersting period,the seedling stage and the booting stage and its correlation analysis were conducted,using 204 accessions of core collection of rice( Oryza sativa L.)in China.The results showed that there were obvious different cold tolerance between Japonica rice and Indica rice of sub species,and among rice germplasms.The cold tolerance of Japonica rices was stronger than those of Indica rices,but there were some stronger cold tolerant germplasms of Indica rices.The Japonica rices such as Gaoyangdiandaodahongmang,Feidongtangdao,Muxiqiu,Weiguo,Xingguo,Shanjiugu,Zhonghua 8 ect.and Indica rices such as Baoxuan 21,Hongmisandanbai,Cungunuo,Honggu ect.were showed stronger cold tolerance in several growing stages,which should be used in rice breeding for cold tolerance and identification of gene associating with cold tolerance.The seed setting rate under natural low temperature and cold water irrigation were significantly positively correlated with the vigor of germination under low temperature,while which were significantly negatively correlated with dead seedling rate,that was the rice germplasms with stronger cold tolerance at the germination period and the bud busting period under low temperature,had stronger cold tolerance at the booting stage.So the vigor of germination and dead seedling rate under low temperature could be used as cold tolerant index of cold tolerance at the booting stage in early growing stage.