水稻质核互作雄性不育系的微效恢复基因定位和排除方法研究  

Studies on Mapping and Discarding of Minor Fertility Genes in Rice CMS Lines

作　　者：李新奇 袁隆平[2] Susan McCouch[1] 

机构地区：[1]Department of Plant Breeding&Biometry,Cornell University,Ithaca,NY14853,USA [2]国家杂交水稻工程技术研究中心

出　　处：《杂交水稻》2010年第S1期276-281,共6页Hybrid Rice

基　　金：湖南省自然科学基金(01JJY2025)

摘　　要：以232个协青早A/B456///协青早A/B456∥B456植株组成的分离群体为材料,调查花粉可育率和自交结实率,并采用121个在染色体上分布比较均匀的SSR多态性标记进行QTL检测。发现22个SSR标记分别与10个花粉育性位点连锁,分布于第2,5,6,8,10,12染色体上;28个标记分别与16个小穗育性位点连锁,分布于第1,2,4,5,6,8,10和11染色体上;13个标记同时与花粉育性和小穗育性连锁,小穗育性与花粉育性QTL差异是花粉可育度和自交结实率不平行性的遗传基础。各可育位点对花粉育性和小穗育性的提高效应比较小,为微效基因,但每个花粉育性位点的存在都可导致不育系败育不彻底。协青早A中发现1个花粉可育位点Pf 5-1,与分子标记Bm 55和Rm 13紧密连锁,进行分子标记辅助选择,可能排除协青早A的微效恢复基因(可育位点),达到完全不育。协青早A存在8个小穗育性位点,能够提高自交结实率,有助于杂种F1结实率的提高,有利于提高不育系的可恢复性。多数微效恢复基因显示为部分隐性或隐性,是水稻质核互作雄性不育系选育难的重要原因。采用不育系/拟用亲本∥保持系/拟用亲本的方式,观察杂种育性分离,可对拟用亲本的微效恢复基因有所了解,用保持系/部分保持系∥保持系的方式可提高微效恢复基因排除的效率。The population of 232 Xieqingzao A/B456///Xieqingzao A/B456∥B456 plants was used to map pollen and spikelet fertility QTLs by means of a total of 121 selected SSR markers evenly distributed on rice genome.There were 22 markers linking with 10 pollen fertility QTLs located on Chromosomes 2,5,6,8,10 and 12,and 28 markers linking with 16 spikelet fertility QTLs located on Chromosomes 1,2,4,5,6,8,10 and 11.Of them,13 markers linked with both pollen fertility and spikelet fertility.The QTL difference between pollen fertility and spikelet fertility was the genetic basis of the inconsistency between them.Each QTL had only a small effect on raising fertility so they were all minor genes.However,any one of them would result in incompleteness of male sterility of CMS lines.In Xieqingzao A,Pf5-1,a fertility QTL closely linked with markers Bm 55 and Rm 13,was found so that it could be discarded to achieve a complete male sterility by way of the marker-assisted selection in breeding program.There were 8 spikelet fertility QTLs in Xieqingzao A which could only raise spikelet fertility but not pollen fertility,so they would enhance the spikelet fertility of F1 hybrids and be favorable for improving the restorability of Xieqingzao A.Most of the minor fertility genes were recessive or incompletely recessive genes,which explains well the reason for the difficulty in breeding CMS lines with complete sterility.The minor fertility genes could be better understood in a candidate parent by observing the fertility segregation in the population of ″a CMS line/a candidate parent∥the maintainer line/the candidate parent″,and the crossing pattern of ″maintainer lines/candidate parents∥maintainer lines″ would help increase the efficiency in discarding minor fertility genes in breeding of CMS lines.

关 键 词：水稻 细胞质雄性不育 微效恢复基因 SSR分子标记 

分 类 号：S511[农业科学—作物学]