Song Lai-Qiang, Fu Ting-Dong, Tu Jin-Xing, Ma Cao-Zhi, Yang Guang-Sheng
National Key Laboratory of Crop Genetic Improvement, National Sub-center of Rapeseed Improvement in Wuhan, Huazhong Agricultural University, Wuhan, 430070 Hubei, China.
Theor Appl Genet. 2006 Jun;113(1):55-62. doi: 10.1007/s00122-006-0271-9. Epub 2006 Apr 20.
Dominant genic male sterility (DGMS) has been playing an increasingly important role, not only as a tool for assisting in recurrent selection but also as an alternative approach for efficient production of hybrids. Previous studies indicate that fertility restoration of DGMS is the action of another unlinked dominant gene. Recently, through classical genetic analysis with various test populations we have verified that in a DGMS line 609AB the trait is inherited in a multiple allelic pattern. In this study, we applied molecular marker technology to provide further validation of the results. Eight amplified fragment length polymorphism (AFLP) markers tightly linked to the male sterility allele (Ms) were identified in a BC1 population from a cross between 609A (a sterile plant in 609AB) and a temporary maintainer GS2467 as recurrent parent. Four out of the eight markers reproduced the same polymorphism in a larger BC(1) population generated with microspore-derived doubled haploid (DH) parents (S148 and S467). The two nearest AFLP markers SA12MG14 and P05MG15, flanking the Ms locus at respective distances of 0.3 centiMorgan (cM) and 1.6 cM, were converted into sequence characterized amplified region (SCAR) markers designated SC6 and SC9. Based on the sequence difference of the marker P05MG15 between S148 and a DH restorer line S103, we further developed a SCAR marker SC9f that is specific to the restorer allele (Mf). The map distance between SC9f and Mf was consistent with that between SC9 and Ms allele. Therefore, successful conversion of the marker tightly linked to Ms into a marker tightly linked to Mf suggested that the restoration for DGMS in 609AB is controlled by an allele at the Ms locus or a tightly linked gene (regarded as an allele in practical application). The Ms and Mf-specific markers developed here will facilitate the breeding for new elite homozygous sterile lines and allow further research on map-based cloning of the Ms gene.
显性核雄性不育（DGMS）不仅作为一种辅助轮回选择的工具，而且作为一种高效生产杂交种的替代方法，发挥着越来越重要的作用。先前的研究表明，DGMS的育性恢复是另一个不连锁显性基因的作用。最近，通过对各种测试群体进行经典遗传分析，我们证实了在一个DGMS系609AB中，该性状是以复等位基因模式遗传的。在本研究中，我们应用分子标记技术对结果进行进一步验证。在609A（609AB中的不育株）与临时保持系GS2467作为轮回亲本杂交产生的BC1群体中，鉴定出8个与雄性不育等位基因（Ms）紧密连锁的扩增片段长度多态性（AFLP）标记。在由小孢子衍生的双单倍体（DH）亲本（S148和S467）产生的更大的BC1群体中，8个标记中的4个表现出相同的多态性。两个最接近的AFLP标记SA12MG14和P05MG15，分别位于Ms位点两侧，距离为0.3厘摩（cM）和1.6 cM，被转化为序列特征扩增区域（SCAR）标记，命名为SC6和SC9。基于标记P05MG15在S148和DH恢复系S103之间的序列差异，我们进一步开发了一个对恢复等位基因（Mf）特异的SCAR标记SC9f。SC9f与Mf之间的图谱距离与SC9和Ms等位基因之间的图谱距离一致。因此，成功地将与Ms紧密连锁的标记转化为与Mf紧密连锁的标记，表明609AB中DGMS的恢复受Ms位点的一个等位基因或一个紧密连锁基因（在实际应用中视为一个等位基因）控制。这里开发的Ms和Mf特异标记将有助于新的优良纯合不育系的选育，并允许对Ms基因的图位克隆进行进一步研究。
