摘要
以具有早世代稳定特性的9个水稻品系和7个栽培稻进行杂交得到130个杂交组合。发现在同一个组合的F2群体中除出现孟德尔式分离株系外还出现性状整齐一致的稳定株系,在F2群体中出现了32个不同农艺性状的稳定株系。SSR标记结果表明:稳定株系F2与其F1单株的标记一致,都是纯合的,且双亲的标记在后代都有出现,双亲的标记位点在后代的染色体上同时出现,说明稳定株系为真杂种;分离株系F2与其F1单株SSR标记均为杂合;大部分稳定株系在RM276、RM258、RM248、RM1这4个标记位点都较高频率地出现非父母带型。推测出现变异的配子激活杂种合子体细胞减数分裂,合子经过减数分裂后,4个单倍体细胞经过胚胎发育选择,其中一个细胞染色体加倍而发育为纯合的二倍体植株。
One hundred and thirty hybrids derived from the crosses between nine rice strains stabilized in early generation and seven cultivars(Oryza sativa L.).In their F2 populations,32 uniform strains of different agronomic traits were observed.In the same combination of these uniform strains,there were strains segregating in the Mendelian manner.SSR markers analysis showed that F2 and F3 populations of the uniform strains and their F1 plants displayed the same markers indicating all the uniform strains were homozygous.All the marker bands of parents were simultaneously present on their progeny chromosomes,indicating that the uniform strains must true hybrid origin.The SSR markers of F2 population of segregating strains and their F1 plants showed that the segregating strains were heterzygosity.SSR marker band sites of RM276,RM258,RM248 and RM1 loci in most uniform strains presented at high frequencies bands site different from their parent's,We suggested that during the gamete formation,the genes that linked to ga-1,Rf and ga-8 mutated at certain frequency,and followed by a somatic meiosis of the fecundated zygote.Thus a haploid cell may develop into a homozygous embryo,and the F1 plant was homozygous and the progeny stabilized in early generation.
作者
周黎军
敖光辉
吴先军
李仕贵
ZHOU Li-Jun;AO Guang-Hui;WU Xian-Jun;LI Shi-Gui(Rice Research Institution of Sichuan Agricultural University,Wenjiang 611130,China;Yibin Vocational and Technical College,Yibin 644003,China)
基金
国家自然科学基金(编号:30001037)
全国优秀博士论文作者专项基金(编号:200054)项目
关键词
SSR
早世代稳定
非父母带
体细胞减数分裂
SSR(short sequences repeats)
early generation stability strain
non-parents bands
somatic meiosis
