万寿菊舌状花花冠裂片突变体的形态鉴定及连锁标记开发

Morphological Identification and Development of Linkage Markers for Lobed Ray Floret Mutants in Marigold(Tagetes erecta)

万寿菊(Tagetes erecta)是菊科万寿菊属重要的观赏花卉,其舌状花花冠边缘的类型有平滑(smooth)、波浪(undulate)及不同程度的缺刻(incision)等。以第1轮小花花冠筒边缘五裂且雄蕊发育正常的万寿菊突变体JH和舌状花花冠边缘平滑且雄蕊败育的万寿菊自交系S5为亲本构建F_(2)代分离群体。遗传分析表明,JH突变性状由显性单基因控制,将其命名为Telf。组织学和细胞学观察发现JH第1轮小花为舌状花管瓣化,其花冠筒顶部具有5个裂片,中下部融合呈管状,且花药和花粉粒发育恢复正常。利用BSR-seq和比较基因组学方法,将控制舌状花花冠裂片形成的基因Telf定位于37003-SCAR标记和34032-CAPS标记之间,2个标记距Telf的遗传距离分别为3.684 cM和3.517 cM。该研究为后续精细定位目的基因Telf奠定了基础,也为万寿菊分子标记开发提供了新方法。

Marigold(Tagetes erecta)is an important ornamental plant of the genus Tagetes in the Asteraceae.The morphology of its ray floret corolla varies from smooth,undulate to different degree of incision.An F_(2) population was constructed from a cross between the mutant marigold JH with five-lobed corollas and fertile stamens in the first round florets and the inbred line S5 with smooth corolla of ray florets and aborting stamens.Inheritance analysis showed that the mutation trait of JH was controlled by a single-dominant gene,named Tagetes erecta lobed ray florets(Telf).Histological and cytological observations showed that the first round ray florets of JH were disk-like,with five lobes formed at the top of the corolla tube,the middle and lower parts were tubular,and the development of anthers and pollen grains are to normal.Using BSR-seq and comparative genomics methods,the gene Telf controlling lobed ray florets was mapped in the interval of 37003-SCAR and 34032-CAPS.37003-SCAR marker was 3.684 cM from the Telf gene.On the other side of the gene,34032-CAPS marker was placed about 3.517 cM from Telf.This study laid a foundation for the subsequent fine mapping of the target gene Telf,and also provided a new method for the selection of molecular markers in marigold.