广西水稻地方品种耐冷性鉴定及相关分析

对419份广西水稻地方品种初级核心种质进行芽期、苗期的耐冷性鉴定及相关分析,结果表明:广西水稻地方品种芽期、苗期耐冷性主要集中在7级和9级,总体耐冷性较弱。芽期、苗期极强耐冷种质(1级)分别为24份和27份,占参试总数的5.73%和6.44%,其中10份种质芽期和苗期均表现极强耐冷(1级)。芽期、苗期耐冷性呈极显著正相关(r=0.66)。粳稻芽期、苗期耐冷性均显著高于籼稻;粘糯稻之间耐冷性差异是由籼粳稻类型的耐冷差异引起的;来自高寒山区稻作区的品种芽期和苗期平均耐冷表现最强。利用34个SSR标记与芽期、苗期耐冷性进行Pearson相关分析,在第7和第9染色体上,各鉴定出1个同时与芽期和苗期耐冷性相关联的位点。本研究为水稻芽期、苗期耐冷育种提供新的抗源材料,并为水稻耐冷基因定位及机理研究奠定基础。

Evaluation and correlation analysis of Cold Tolerance of Guangxi Landrace Rice

Cold tolerance of 419 accessions of primary rice core collection from Guangxi was evaluated at geminating and seedling stages. The results indicated that the cold tolerance at geminating and seedling stages mainly concentrated in grade-7 and 9, most of the accessions were sensitive to cold. 24 and 27 accessions were classed into the high-level tolerance (Grade 1) at germinating and seeding stage, accounting for 5.73% and 6.44% of the total accessions, respectively. There is highly positive correlation (r = 0.66) between the cold tolerance scores at two stages. There were significant differences of cold tolerance between Indica and Japonica, non-glutinous rice and glutinous rice. Cold tolerance of Japonica was significantly higher than Indica at geminating and seedling stages. Cold tolerance of glutinous rice was significantly higher than non-glutinous rice at the geminating stage, but no difference at seedling stages. The rice collected from alpine areas showed much higher cold tolerance than Guinan and Guibei rice regions, no difference with Guizhong rice regions. Correlation analysis was carried on using 34 SSR markers. Two loci, at 7th and 9th chromosome, respectively , were identified to have a correlation with cold tolerance at both geminating and seedling stages. The study will provide elite rice germplasm of cold tolerance and a basis for mapping and cloning cold tolerance in rice.