基于农艺性状和分子标记的甘薯遗传多样性分析及指纹图谱构建

Genetic diversity analysis and fingerprint map construction of sweetpotato based on agronomic traits and molecular markers

【目的】基于农艺性状和分子标记对福建甘薯品种进行遗传多样性分析及指纹图谱构建,为福建省甘薯育种亲本选配和遗传背景研究提供理论依据。【方法】以福建省育成及引进的24个甘薯品种为研究对象,对其农艺性状进行调查测定,利用筛选出的28条ISSR引物和27对SRAP引物进行遗传多样性分析,利用SPSS 26.0的组间联接法和平均欧式距离法进行农艺性状聚类分析;利用NTSYS-pc 2.1进行分子标记聚类分析。基于ISSR和SRAP扩增结果进行指纹图谱构建。【结果】农艺性状聚类分析结果显示,在欧氏距离为8时,24个甘薯品种被分为三大类:第Ⅰ类为泉薯76、泉薯12号和龙薯14号;第Ⅱ类包含徐紫薯2号、泉薯10号、莆薯20、福薯24号、莆紫薯18和福宁紫3号;其余15个品种归在第Ⅲ类。28条ISSR引物和27对SRAP引物分别扩增条带362和364条,多态性比率分别为78.73%和83.79%,部分引物多态率高达100.00%,平均等位基因数(Na)分别为1.7676和1.8307;平均有效等位基因数(Ne)分别为1.4071和1.4631,平均Nei’s基因多样性指数(H’)分别为0.2435和0.2730,平均Shannon’s信息指数(I)分别为0.3705和0.4124。基于ISSR分子标记,24个甘薯品种的遗传相似系数为0.674~0.851,在遗传相似系数0.728处可分为三大类:第Ⅰ类仅包含福宁紫3号,第Ⅱ类包含福薯24号、徐紫薯2号、莆薯20、莆薯53、莆紫薯18、莆紫薯3号、福薯404和莆薯16,其余15个品种归为第Ⅲ类。基于SRAP分子标记,24个甘薯品种的遗传相似系数为0.591~0.879,在遗传相似系数0.696处可分为三大类,第Ⅰ类仅包含泉薯76,第Ⅱ类包含莆紫薯18和徐紫薯2号,其余21个品种归为第Ⅲ类。引物UBC899可用于构建24份甘薯种质资源的指纹图谱。【结论】ISSR和SRAP分子标记的多态性检测效率较高,均适用于甘薯种质资源的遗传变异分析。24份供试甘薯材料遗传多样性较丰富,农艺性状聚类结果与分子标记聚类结果相似但又有明显差异,ISSR分子标记聚类结果与种质资源系谱更吻合,引物UBC899可用于供试甘薯品种区分。

【Objective】The purpose of the study was to analyze the genetic diversity and construct a fingerprint map of sweetpotato varieties in Fujian based on agronomic traits and molecular markers,so as to provide a theoretical basis for the study of parent selection and genetic background of sweetpotato breeding in Fujian.【Method】Twenty-four sweetpotato varieties bred and introduced in Fujian were used as research subjects to investigate and determine their agronomic traits.The 28 ISSR primers and 27 SRAP primers screened were used for genetic diversity analysis.SPSS 26.0 was used to perform clustering analysis of agronomic traits using the intergroup connection method and the mean Euclidean distance method.NTSYS-pc 2.1 was used for molecular marker clustering analysis.The fingerprint map was constructed according to the ISSR and SRAP amplification results.【Result】The results of agronomic traits clustering analysis showed that 24 sweetpotato varieties were classified into three major groups at a Euclidean distance of 8.GroupⅠconsisted of Quanshu 76,Quanshu No.12 and Longshu No.14.GroupⅡcontained Xuzishu No.2,Quanshu No.10,Pushu 20,Fushu No.24,Puzishu 18 and Funingzi No.3.The remaining 15 species were classified in Group III.The 28 ISSR primers and 27 pairs of SRAP primers amplified 362 and 364 bands respectively,with a polymorphism ratio of 78.73%and 83.79%,and the polymorphism rate of some primers was as high as 100.00%.The average numbers of alleles(Na)were 1.7676 and 1.8307,respectively,the average numbers of effective alleles(Ne)were 1.4071 and 1.4631,the average Nei’s gene diversity index(H')were 0.2435 and 0.2730,the average Shannon’s information index(I)were 0.3705 and 0.4124,respectively.Based on ISSR molecular markers,the genetic similarity coefficients of the 24 sweetpotato varieties ranged from 0.674 to 0.851,and they could be categorized into three major groups at the genetic similarity coefficient of 0.728.GroupⅠcontained only Funingzi No.3,groupⅡcontained Fushu No.24,Xuzishu No.2,Pushu 20,Pushu 53,Puzishu 18,Puzishu No.3,Fushu 404 and Pushu 16,and the remaining 15 varieties were categorized into group III.Based on SRAP molecular markers,the genetic similarity coefficient of the 24 sweetpotato varieties ranged from 0.591 to 0.879,and they could be categorized into three major groups at the genetic similarity coefficient of 0.696.GroupⅠcontained only Quanshu 76,groupⅡcontained Puzishu 18 and Xuzishu No.2,and the remaining 21 varieties were categorized into groupⅢ.The primer UBC899 could be used to construct the fingerprint map of 24 sweetpotato germplasm resources.【Conclusion】ISSR and SRAP molecular markers are efficient in polymorphism detection,and both of them are suitable for genetic variation analysis of sweetpotato germplasm resources.The genetic diversity of the 24 sweetpotato materials for tes-ting is relatively rich,and the clustering results based on agronomic traits cluster results and molecular markers are similar but greatly different.The ISSR molecular clustering results are more consistent with the pedigree map of the germplasm resources,and the primer UBC899 can be used to distinguish the tested sweetpotato varieties.