水稻柱头外露率相关性状的调查及高柱头外露率不育系的创制

Investigation of Characters Related to Stigma Exserted Rate in Rice and Establishment of Male Sterile Line with High Stigma Exposure

虽然杂交稻的应用大大提高了粮食生产产量,缓解了我国粮食安全问题,但是杂交种的生产却制约了杂交稻的进一步发展。提高雄性不育系的柱头外露率是提高杂交种产量的重要途径之一。本研究对在天津地区种植的一些核心亲本进行调查,对影响柱头外露率的相关性状进行测量分析,以期找到影响柱头外露的主要因素。结果发现,柱头及花柱长度对柱头外露率影响较大,且受环境因素影响较小。在育种过程中通过选择长柱头和花柱的后代可以提高柱头外露率。通过引入长柱头的亲本,成功地对不育系及保持系的柱头外露率及异交性状进行了改造,大大提高了杂交稻的制种产量。进一步对以罗2和II-32B构建的F2代群体进行调查分析,发现柱头及花柱总长的分布存在两个主峰,说明这个性状有可能是少数几个基因控制的。

Hybrid rice dramatically increased the yield of rice, alleviated the problem of food security. But a main limiting factor hindering the extension of the hybrid rice application was the low yield of hybrid seed. The efficiency of hybrid seed production could be improved by increasing the percentage of exserted stigma. In this study, some of the core rice varieties were investigated in Tianjin,and the related traits affecting the stigma exsertion were analyzed in order to find out the main factors influencing the stigma exsertion.The result showed that the length of stigma and style had a big effect on stigma exsertion, and it was less affected by environmental factors. So the selection of long stigma and style could help improving the stigma exsertion in the breeding process. By introducing the long stigma from one parent, the stigma exsertion and outcrossing traits had been successfully transformed in the male-sterile and maintainer lines, which greatly improved the seed production of hybrid rice. And the result of further investigated on the F2 population constructed by Luo 2 and II-32 B showed that there were two main peaks in the distribution of the total length of the stigma and style,indicating that the trait might be controlled by few genes.