Construction of genetic linkage map based on a RILs population derived from the hybrid rice Peiai 64S/93-11 and detection of QTL for 1000-grain weight | 培矮64S/93-11重组自交系分子图谱构建及千粒重QTL检测

Chinese. 摘　　要：利用光、温敏核不育系培矮64S与常规品种93-11进行杂交,以单粒传方法建立含217个单株的重组自交系（R ILs）群体。选用775对SSR引物进行亲本多态性筛选,共有170对检测到多态性,频率为21.9%。构建的水稻分子遗传图谱共包含141个标记座位,总图距约2 060.4 cM,标记间平均图距为14.6 cM。群体中标记偏分离情况较严重。以该R ILs群体217个株系为材料,对千粒重性状进行了QTL分析。结果表明：在R ILs群体中检测到3个与千粒重相关的QTL,分别在第1、5、8染色体上,命名为qTGW-1、qTGW-5、qTGW-8,其LOD值为5.51、3.31、4.94,贡献率为17.90%、6.12%、9.59%。qTGW-1控制千粒重的增效基因来自低值亲本培矮64S,qTGW-5和qTGW-8控制千粒重的增效基因来自高值亲本93-11。通过相应的含有154个家系的全基因组染色体片段置换系（CSSLs）群体图示基因型分析,证实了在第1染色体上标记RM315附近存在控制千粒重的增效基因,来源于染色体片段供体亲本培矮64S,使千粒重增加1.03 g;在第5、8染色体上标记RM3663、RM310附近存在控制千粒重的增效基因,来自染色体片段受体亲本93-11,使千粒重分别增加0.63 g和0.80 g。

English. The present study used the photo-thermo sensitive genic male sterile Peiai 64S and 93-11 as the material to develop 217 recombinant inbred lines（RILs）by using SSR marker aided selection.A total of 775 pairs of SSR markers were used to analyze the polymorphism between Peiai 64S and 93-11.It was shown that there were 170 pairs of polymorphism markers and their polymorphic ratio are 21.9%.The linkage map consists of 141 SSR markers.This map covered the rice genome about 2 060.4 cM with about 14.6 cM of average interval.Serious segregation distortion was observed in this RILs population.QTL analysis for the 1 000-grain weight（TGW）was conducted with the RILs of Peiai 64S/93-11 with 217 lines and a genome-wide chromosome segment substitution lines（CSSLs）population with 154 lines.The result indicated that in the RILs population,three QTL controlling the TGW were detected on chromosome 1,5 and 8,named qTGW-1,qTGW-5,qTGW-8,respectively.The LOD values of each QTL were 5.51,3.31 and 4.94,and phenotypic variations were explained by each QTL are 17.90%,6.12% and 9.59%,respectively.The allele of qTGW-1 was derived from Peiai 64S and the other two alleles of qTGW-5 and qTGW-8 were derived from 93-11.Analysis of CSSLs graphical gene types also showed that there was a positive allele on the Peiai 64S chromosome substitution segment near the marker RM315 locating on the chromosome 1 which certificated the existence of qTGW-1,and also that there were other two negative alleles on the Peiai 64S chromosome substitution segment near the marker RM3663 and RM310 locating on the chromosome 5 and 8 which proved the existence of the qTGW-5 and qTGW-8.