论文部分内容阅读
“航香糯”是经空间诱变育成的籼型香糯稻品种。与原种南丰糯相比,航香糯的产量和稻瘟病抗性有明显提高,粒形变细长,并带有香味。为深入了解空间诱变的机理以及初步鉴定与性状变异相关的区间,本研究用SSR标记对航香糯与南丰糯进行等位基因变异分析。结果表明,在12条染色体上选取的156个标记位点中检测到45个变异位点,变异频率为28.85%。检测到的变异位点中,42个位点表现为DNA扩增长度的变异,仅1个位点在航香糯中扩增带数增加,另有2个位点在南丰糯中为2条扩增带,而在航香糯中该位点却是扩增带型与诱变亲本小分子量扩增带相同的纯合体(仅1条扩增带),显示诱变后代中部分多态性位点由空间搭载材料杂合态位点的正常基因分离重组产生的。不同染色体上位点变异频率存在较大差异,变异频率最高的染色体是第7、第8和第12染色体,变异频率均达50.00%,变异频率最低的是第6染色体,仅6.25%。变异位点在水稻基因组中随机分布,同时表现成簇分布的特点,显示除点突变外,大片段突变可能也是航天诱变的主要形式。在变异染色体区段有多个已精细定位或克隆的粒型、产量、香味、稻瘟病抗性的QTL座位,这些位点是否与这些性状的变异有关,值得进一步研究。
“Hangxiang waxy ” is a space-induced indica fragrant glutinous rice varieties. Compared with the original species Nanfeng waxy, Hangxiang waxy rice yield and blast resistance increased significantly, slender shape slender, with aroma. In order to understand the mechanism of space mutagenesis and initially identify the intervals related to trait variation, SSR markers were used to analyze allelic variation of Hangxiangnuo and Nanfengnuo. The results showed that in the 156 markers selected on 12 chromosomes, 45 variation loci were detected, and the variation frequency was 28.85%. Among the detected variation sites, 42 loci showed variation of DNA amplification length, only 1 locus was increased in Hangxiang waxy and 2 loci were 2 in Nanfengnuo , But the locus in Hangxiang waxy was the same homozygote (only one band) of the amplification band and the mutagenic parental small molecular weight amplification band, showing some polymorphism in the mutagenized offspring The sex locus is generated by the normal gene isolation and recombination of the heterozygous locus of the space-carrying material. The frequency of site variation on different chromosomes is quite different. The chromosomes with the highest frequency of variation are chromosomes 7, 8 and 12. The frequency of mutation is 50.00%. The lowest frequency of variation is chromosome 6, only 6.25%. The variation loci are randomly distributed in the rice genome and are also characterized by clusters. It shows that in addition to the point mutation, the large fragment mutation may also be the main form of space mutation. There are several fine-mapped or cloned grain size, yield, fragrance and blast resistance-resistant QTL loci in the variegated chromosome segment. Whether these loci are related to the variation of these traits is worth further study.