甜菜多胚种质资源育性组成的分子标记分析

Analysis of the Fertility Composition of Sugar Beet Polyembryonic Germplasm Resources by Molecular Markers

为了了解国家甜菜种质资源库中甜菜多胚种质资源的育性组成情况,为将来应用多胚授粉系同步改良单胚不育系和保持系以及应用多胚保持系做父本更好地进行品种保护打下基础。本研究利用作用于甜菜线粒体VNTR位点的引物TR1进行甜菜细胞质类型的鉴定,并利用甜菜细胞核DNA的bvORF17上游区的多态性进行细胞核Rf1位点基因型鉴定。试验结果表明:627份甜菜多胚种质资源中N型细胞质(可育细胞质类型)有234份,占37%左右;S型细胞质(不可育细胞质类型)289份,占46%左右;N/S型细胞质(既有可育细胞质类型也有不可育细胞质类型)53份和X型细胞质(未知细胞质类型)51份,均占8%左右;其扩增条带大小在500~600 bp。在627份鉴定出细胞质类型的甜菜种质资源中,有237份鉴定出相应的细胞核Rf1位点基因型,其中同时具有1800 bp和1300 bp条带类型的有78份,仅具1800 bp的有159份。627份种质资源中,有390份只鉴定出细胞质类型,细胞核Rf1位点基因型没有鉴定出。对于T1、T2引物扩增条带为1800/1300 bp的种质资源是否是1800/1300 bp型或者1800 bp和1300 bp型二者混合仍未可知。从总体来看,国家甜菜种质资源库中的细胞质类型组成较为复杂,既有N型、S型和N/S型细胞质类型,也有X型细胞质类型;细胞核基因型有2种,共组成7种育性类型,在后续育种中需要对其进行筛选。

In order to understand the fertility composition of sugar beet polyembryonic germplasm resources in National Beet Medium-term Gene Bank,and to lay the foundation for the future application of polyembryonic pollination lines for the simultaneous improvement of monogerm sterile and maintainer lines and for the application of multigerm maintainer lines as parents for carrying out variety protection better.The experiment used the primer TR1,which acts on the mitochondrial VNTR locus of sugar beet,to identify sugar beet cytoplasmic types,and used the polymorphism of the upstream region of bvORF17 in sugar beet nucleus DNA to identify the genotype of the Rf1 locus in the nucleus.The results showed that,among the 627 sugar beet multigerm germplasm resources,234 were N-type cytoplasm(fertile cytoplasm type),which accounted for about 37%;289 were S-type cytoplasm(sterile cytoplasm type),which accounted for about 46%;and 53 were N/S-type cytoplasm(both fertile and sterile cytoplasm type),in addition,51 were X-type cytoplasm(unknown cytoplasm type),which accounted for about 8%,and the size range of amplified bands was 500-600 bp.Of the 627 sugar beet germplasm resources identified with a cytoplasmic type,237 were identified with a corresponding nucleus Rf1 locus genotype,including 78 with bands of 1800 bp and 1300 bp,and 159 with bands of 1800 bp.Among 627 germplasm resources,390 germplasm resources were only identified cytoplasmic type,but nucleus Rf1 locus genotype was not identified.It was still unknown whether the germplasm resources with T1 and T2 primers amplifying bands of 1800 bp/1300 bp was 1800/1300 bp types or a mixture of the both.In general,the cytoplasmic types in National Beet Medium-term Gene Bank are complex in composition,with N,S and N/S cytoplasm types,as well as X cytoplasm types.There are two nucleus genotypes,making up a total of seven fertility types,which will be used in further selection.