不同生态条件下籼粳稻杂交后代亚种特性的比较研究

以中优早8号×丰锦F₆重组自交系群体为试材，在辽宁和四川两个不同的生态区种植，研究亚种特性变化的结果表明，两个地区都呈偏粳分布。不同生态条件下亚种特征性状发生了明显变化，总体上四川表现比辽宁更加偏粳，进一步分析显示籼及偏籼型四川比辽宁表现更加偏籼，而粳及偏粳型更加偏粳。生态条件对程氏指数6性状的影响因性状而异，1~2穗节长、叶毛四川比辽宁偏粳，籽粒长宽比、抽穗时壳色四川比辽宁偏籼。生态条件对程氏指数6性状间和程氏指数与维管束性状间的相关性也有显著影响。籼粳稻杂交后代的维管束性状在不同生态条件下有显著变化，四川穗颈大维管束数比辽宁明显减少，而穗颈小维管束数和第二节间小维管束数明显增加，大小维管束比降低，大维管束比增加。总体上虽然有大小维管束比籼型>粳型，大维管束比籼型<粳型的趋势，但是大小维管束比和大维管束比不能作为籼粳稻分类的指标，籼粳稻杂交后代亚种特性与维管束性状已经重新组合。

Subspecies Characteristics in Filial Generation of Cross between Indica and Japonica under Different Environments

The RILs population derived from the cross between "Zhongyouzhao 8"(Hsien or Indica) and "Fengjin"(Keng or Japonica) was grown in Liaoning and Sichuan provinces to compare the subspecies characteristics under different environments.The results showed that the distribution of Cheng's index was japonicalinous.The population was more japonicalinous in Sichuan than in Liaoning as a whole. Further analysis indicated that indica and indica-cline in Sichuan were more indicalinous than those in Liaoning,japonica and japonica-cline in Sichuan were more japonicalinous than those in Liaoning.The effects of environment on six characteristics of Cheng's index were different because of different characteristics,as well as on the correlations between the six characters,the Cheng's index and the vascular bundle traits.For example,the length of the first and second rachises and leaf pubescence were more japonicalinous in Sichuan than in Liaoning,while the length/width ratio of spikelets and glume color at heading time were more indicalinious in Sichuan than in Liaoning.The vascular bundle characteristics of RILs in different environments changed remarkably.The number of large vascular bundles in panicle neck was less in Sichuan than in Liaoning,and the number of small vascular bundles in panicle neck and the second top stem was greater in Sichuan than in Liaoning.The ratio of large to small vascular bundles in panicle neck was decreased and the ratio of large vascular bundles between the second top stem and panicle neck was increased in Sichuan.Though total trend was the vascular bundle ratio of large to small in indica was greater than that in japonica and the ratio of large vascular bundles in indica was less than that in japonica,it is not appropriate that the vascular bundle ratio of large to small and the ratio of large vascular bundles are regarded as the parameters for subspecies classification in rice.The vascular bundles characteristics from typical indica or japonica were recombined in the population derived from indica and japonica crossing.