分子标记辅助构建同质同核近等基因恢复系L-Rf5

红莲型水稻恢复系9311中有2个红莲型恢复基因Rf5和Rf6,不育系YTA中有2个不育基因orfH79和orf216;为了研究2个恢复基因与2个不育基因之间的互作关系,将红莲型水稻不育系YTA与恢复系9311杂交,杂种后代再以YTA为轮回亲本回交8代;根据Rf5基因序列设计特异分子标记,并对L-Rf5进行检测,结合花粉镜检结果,筛选出只含Rf5的纯合株系,多代自交后其表型一致,说明纯合株系L-Rf5构建成功;对近等基因恢复系的不育基因orfH79和orf216的表达量进行分析,结果显示:L-Rf5中orfH79的表达量较YTA明显下降;纯合的L-Rf5比杂合的L-Rf5不育基因orfH79的表达量稍低;L-Rf5中orf216的表达量较YTA下降并不明显。同时克隆了YTA、9311、近等基因恢复系中Rf1B序列,发现它们之间没有差异。

Construction of near-isogenic restore line L-R f5 with isonucleus and isocytoplasmic through marker-assisted

There are two fertility restorer genes,R f5 and R f6 in 9311 and two sterility genes orfH79 and orf216 in YTA.To study the interaction between two restorer genes and two CMS genes in Honglian (HL) rice,HL-CMS line YTA was crossed with the restore line 9311.Then,F1 was backcrossed repeatedly as the male parent with the YTA as recurrent male parent for more than eight generations.Based on the sequences of R f5,we designed the specific primers and tested the restorer gene in L-Rf5.Combing with the pollen fertility,we did not find genetic divergence in self-crossed progenies.It suggested that the homozygous L-R f5 was constructed successfully.By analyzing the expression level of HL-CMS gene orfH79 and or f216 in L-R f5,we found that the expression level of orfH79 in L-R f5 decreased distinctly than that in YTA.There is no obvious difference between the homozygous L-R f5 and the heterozygous L-Rf5.However,The expression of orf216 in L-R f5 was not significantly decreased compared with YTA.Meanwhile,the Rf1B sequences of YTA,9311,near isogenic lines were cloned,and we found no difference in these materials.This study laid the foundation for molecular analysis of the restoration of fertility gene Rf1B.