Touzet Pascal, Hueber Nathalie, Bürkholz Alexandra, Barnes Stephen, Cuguen Joël
Laboratoire de Génétique et Evolution des Populations Végétales, UMR-CNRS 8016, FR CNRS 1818, Université de Lille I, 59655 Villeneuve d'Ascq Cedex, France.
Theor Appl Genet. 2004 Jun;109(1):240-7. doi: 10.1007/s00122-004-1627-7. Epub 2004 Apr 14.
Cytoplasmic male sterility (CMS) has been used in the breeding of sugar beet for decades but is also more generally an important feature of the reproductive system in its wild relative, Beta vulgaris ssp. maritima. Among the several CMSs found in wild populations, the G CMS is a mitochondrial variant of the respiratory chain. The segregants derived from a cross between a restored plant and a female (male-sterile) plant on G cytoplasm exhibited three sexual phenotypic classes: female, hermaphrodite and intermediate. The pattern of segregation suggests a genetic inheritance with two loci in epistatic interaction. Nevertheless, it was possible to apply a bulk segregant analysis approach to search for AFLP and microsatellite markers linked to the restorer locus ( RfG(1)) which controls the capacity to produce pollen [female versus non female (i.e. intermediates and hermaphrodites)] in the segregating population. A linkage group was constructed with four AFLP markers and nine microsatellites, and a total size of 40 cM (Kosambi). The closest marker, a microsatellite, was totally linked to RfG1, which was also flanked by two AFLP markers delimiting a 5 cM window. This linkage group was identified as being chromosome VIII where neither of the restorer loci of the Owen CMS are located.
细胞质雄性不育（CMS）已在甜菜育种中应用了数十年，但在其野生近缘种海甜菜（Beta vulgaris ssp. maritima）的生殖系统中也是一个更普遍的重要特征。在野生种群中发现的几种CMS中，G CMS是呼吸链的一种线粒体变体。从具有G细胞质的恢复系植株与雌性（雄性不育）植株杂交产生的分离后代表现出三种性表型类别：雌性、雌雄同体和中间型。分离模式表明这是一种由两个位点上位相互作用的遗传方式。然而，有可能应用混合分离群体分析法来寻找与恢复基因座（RfG(1)）连锁的AFLP和微卫星标记，该基因座控制分离群体中产生花粉的能力[雌性与非雌性（即中间型和雌雄同体）]。构建了一个包含四个AFLP标记和九个微卫星的连锁群，总长度为40厘摩（科萨比）。最接近的标记，一个微卫星，与RfG1完全连锁，其两侧也有两个AFLP标记，界定了一个5厘摩的窗口。这个连锁群被确定为八号染色体，欧文CMS的恢复基因座都不在该染色体上。
