我国西南地区粳稻品种抽穗期的遗传分析

摘要

Heading dates of 26 japonica rice cultivars native to Southwest China were investigated, and their basic vegetative growth(BVG), photoperiod-sensitivities(PS) and temperature-sensitivities(TS) were analyzed under artificially short-day and natural long-day conditions in Nanjing of Jiangsu Province, China, as well as artificially high temperature and natural low temperature conditions in winter in Hainan Province, China. The results showed that the PS and TS varied with different cultivars. The BVGs of all the japonica cultivars were well situated, but differed in cultivars. Regression analysis showed a significant correlation between heading date and PS, indicating that PS was the main factor affecting heading date of japonica cultivar in Southwest China. Genetic analyses were conducted on these 26 cultivars using a set of heading date near isogenic lines as tester lines. The results showed that all these japonica eultivars carried the dominant early-heading gene Ef-1 or Ef-1t, and most of these cultivars carried the dominant photoperiod sensitivity allele E1 or E1 t, the PS of which was slightly weaker than E1. For the Se-1 locus, these japonica cultivars mainly carried recessive photoperiod insensitivity gene Se-1 e. In addition, the recessive allele hd2 could repress or weaken the PS of 22 japonica cultivars by inhibiting the expression of E1 and Se-1. These results indicate that the heading date genotypes determined different PS and well situated BVG in japonica rice cultivars of Southwest China. The above results would be useful for breeding and expanding new japonica cultivars with well adaptability in Southwest China.%设置长日高温、长日低温、短日高温和短日低温4组环境,对我国西南地区26份丰栽粳稻品种的感光性、感温性及基本营养生长性进行了分析.西南地区各梗稻品种表现出不同程度的感光性和感温性,基本营养生长性整体表现适中,品种间也存在着一定的差异.回归分析发现,抽穗期长短与品种的感光性呈显著相关,感光性是影响西南地区梗稻品种抽穗期长短的主要因素.以一套抽穗期上基因近等基因系以及2个QTL近等基因系为测验品种分析26份粳稻品种的抽穗期基因型.结果表明,西南地区粳稻品种携带有显性早熟等位基因Ef-1或Ef-1<'t>,多数品种在E<,1>位点都携带主效显性感光等位基因E<,1>或感光性比E<,1>稍差的E<,1>;在Se-1位点,大部分品种携带非感光等位基因Se-1<'e>;另外,有22个品种还携带可部分抑制Se-1、E<,1>表达的隐性感光抑制因子hd2.进一步明确了我国西南地区粳稻品种的抽穗期基因型,揭示了该地区粳稻品种具有不同程度感光性、感温性和适中基本营养生长性的遗传基础,为该地区粳稻品种的选育和推广提供了依据.