| As one of the native of banana, China is one of countries for banana production in the world. A large number of the microsatellite markers are the base on the fast identification of banana varieties, the analysis of germplasm genetic relationship, construction of molecular genetic map, the mapping of important characters for QTLs, the assistance of molecular breeding and so on. SSR markers have particular advantages, such as operation convenient, codonminant genetic and well repeatability. So it is common utilized in the plant genetics and crop breeding. However, the development, characterization and utilization of SSR markers in Musa are very limited, until now we haven't found any research reports about the development of Musa SSR markers in our country. We are the first to develop Musa SSR markers by Selectively Amplified Microsatellite and Transferability of Amplified Microsatellite from cotton SSRs. Meanwhile, those locus-specific SSR markers identified and characterized by ourselves were used to analyze the genetic diversity among 20 banana cultivars and 4 Musa. bilbisiana. The major results are as follows:①This research successfully developed 41 SSR markers from Musa. acuminate and Musa. bilbisiana by selectively amplified microsatellite (SAM) analysis. The efficiency of SSR markers development was 48% from sequencing data to operationally useful loci.②The 5′anchored primers were substituted with designed special primers at last step in the SAM method, which enhanced the special and stable amplification of primer pairs. The improved SAM method is more suitable to the plant genomes with larger size.③This is the first report about the SSR molecular markers of Dicotyledoneae amplified transferability to Monocotyledoneae. 2940 SSR Markers from cotton were screened for the transferability to Gongjiao (M. acuminata) and Yejiao (M. bilbisiana). There were 409 primer pairs to have effective amplifying, of which, 268 polymorphic primer pairs were selected for characterization on the 24 Musa genotypes with various genomic composition and distinct ploidy level. As a result, a total of 1985 alleles were obtained in all and averaged 7.2 alleles per locus. PIC ranged from 0.58 to 0.91. The polymorphic SSR markers rate was 9.1% from original selection. It showed that SSR markers can be transfered between the plants, which come from different classes.④The genomic SSR markers and the EST-SSR markers was 111 and 157 respectively in the 268 polymorphic cotton SSR markers. The transfer rate of EST-SSR (11.7%) was higher than the genomic (7.0%) from original selection. It confirmed that the transferability rate of EST-SSR was higher than the genomic SSRs.⑤Based on the data of PCR amplification of 41 developed SSR primer pairs from Musa on the 24 Musa genotypes, with a similarity coefficient criteria of 0.60 tested accessions, were clustered into 5 groups by UPGMA, that closely corresponds with genomic composition.⑥Based on the data of PCR amplification of 268 polymorphic cotton primers on the 24 accessions, The cluster analysis with UPGMA revealed that they were also divided into 5 groups at similarity coefficient being 0.62 to 0.63. Compared with the Musa genomic SSRs, the clusters of 17 varieties were the same, except 7 varieties.⑦Huajiao and Hainansuandajiao were divided into the same group at similarity coefficient being 0.68 to 0.76 by all UPGMA analysis. It showed that they have closer genetic relationship.⑧There was closer genetic similarity between Yunanyejiao No1 and Haikouyejiao in all UPGMA analysis, except the different results of Yejiao. And Yunanyejiao No2 showed that it was closer to the A-genomic, which need to be further studied.⑨In this research, we developed and characterized 309 Musa special SSR markers by SAM and Transferability Amplification of Microsatellite from cotton SSRs, which are useful for further research in banana genetics and breeding. What's more, the number of these primers were more than others reports in other countries.
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