利用荧光SSR标记构建含笑种质指纹图谱

Construction of Fingerprint of Michelia Germplasm by Fluorescent SSR Markers

本研究基于高通量荧光SSR标记基因分型技术构建了16份含笑种质的指纹图谱。13对来自近缘种的SSR标记共检测到102条等位片段,每个位点等位基因数5~11不等,平均为7.8个。观测杂合度(Ho)变化范围为0.125 0~0.562 5,平均为0.365 0;期望杂合度(He)变化范围为0.670 3~0.911 3,平均为0.809 9;多态信息量(PIC)变化范围为0.574 8~0.871 4,平均为0.751 5。优选的4对核心引物中,LT106与SGA5组合、LT106与LT58组合以及SGA5与MMA51组合可完全区分16份含笑种质。聚类结果显示16份含笑种质遗传相似系数在0.70~0.90之间,同一种内的不同个体均能很好的聚在一起。本研究建立的荧光SSR基因分型体系高效、快速、准确,不但能为含笑属种质鉴定及新品种保护提供科学理论依据,同时也能为含笑进一步育种工作奠定坚实的基础。

The fingerprint of 16 Michelia germplasm was established by high throughput genotyping technology of fluorescent SSR marker in this study.102 alleles were detected by 13 pairs of SSR markers from closely related species,and the number of alleles per locus ranged from 5 to 11,with an average of 7.8 alleles.The observed heterozygosity（Ho）,the expected heterozygosity（He） and the polymorphic information content（PIC） varied from 0.125 0～0.562 5（mean 0.365 0）,0.670 3～0.911 3（mean 0.809 9） and 0.574 8～0.871 4（mean 0.751 5）,respectively.Among the 4 optimal pairs of core primers,LT106 and SGA5 combinations,LT106 and LT58 combinations and SGA5 and MMA51 combinations could completely distinguish 16 Michelia germplasm.The cluster analysis showed that the similarity coefficient of the 16 Michelia germplasm ranged from 0.70～0.90,and the different individuals from the same species could be clustered in the same branch.The fluorescence SSR genotyping system established in this study was efficient,rapid and accurate,which could not only provide scientific theoretical basis for the identification of germplasm and the protection of new varieties of the genus Michelia,but also provide a solid foundation for the further breeding of Michelia.