切花菊瓶插寿命的关联分析与QTL定位

为揭示切花菊瓶插寿命的数量遗传变异机制及其相关的分子标记,以80个切花菊品种和100个‘南农雪峰’ב蒙白’F1代杂交株系为材料,系统调查瓶插寿命的表型变异,并通过关联分析和连锁作图解析瓶插寿命的遗传机制。结果表明,切花菊品种的瓶插寿命为20～58 d,变异系数为17.96%;F1群体瓶插寿命在24～56 d之间,基本符合正态分布,且普遍存在超亲个体。基于混合线性模型(MLM)的关联分析检测到6个与瓶插寿命性状显著相关的标记,单个标记的表型贡献率为8.67%～11.26%,其中,标记SSR131-3、SSR149-4和SSR150-5的贡献率较高,分别为10.20%、11.26%和11.14%,应为主效位点;QTL定位分析在‘南农雪峰’连锁图的X2连锁群检测到2个控制瓶插寿命性状的加性QTL(qVLX2-1、qVLX2-2),其加性效应分别为11.60和10.86 d,贡献率分别为6.34%和3.15%。

Association Analysis and QTL Mapping for Vase Life of Cut Chrysanthemum

To examine the quantitative genetic mechanism of vase life of cut chrysanthemum，with the attention of future genetic improvement，80 cut chrysanthemum cultivars and the previously established‘Nannong Xuefeng’בMonalisa’F1 mapping population were used to investigate phenotypic variation of vase life. Genome-wide association analysis and QTL mapping were performed to dissect the genetic control of vase life. The results showed that 80 cut chrysanthemum varieties varied in a range of 20–58 d for vase life with a coefficient of variation 17.96%. The vase life in the F1 population ranged between 24–56 d in a normal distribution，and some transgressive individuals were observed in both directions. The mixed linear model（MLM）based association analysis detected six marker sites significantly associated with the vase life，with phenotypic contribution rate ranging from 8.67% to 11.26%. Markers SSR131-3，SSR149-4 and SSR150-5 showed a phenotypic contribution rate > 10% and thus should be main-effect alleles. QTL mapping identified two QTLs（qVLX2-1 and qVLX2-2）for vase life at the X2 linkage group of‘Nannong Xuefeng’genetic map at LOD ≥ 2.5，and the additive effects and contribution ratio were calculated at 11.60 d and 10.86 d，6.34% and 3.15%，respectively.