Molecular Variation And Phylogenetic Analysis Of Musa Using CpSSR Marker

As the popular fruits for customers, edible bananas(Musa spp) are perennial herbaceous monocotyledonous flowering plants belonging to the family Musaceae an-d order Zingiberales. Edible bananas are the major staple food in the tropical and subtropical developing countries. Most of edible bananas originated via hybridization between Musa acuminata colla and Musa balbisiana colla.To study the origin of cultivated bananas, we need to find out the original parents. A major achievement was the evidence found for a strong bias towards maternal transmission of cpDNA and paternal transmission of mtDNA in Musa. The genetic way helps us to find out the cultivated bananas original parents, to explore where the banana hybird take place and to establish the pedigree of banana cultivation. In this study,73 cpSSR primers were evaluated in a collection of 42 banana accessions. The main results were as follows:(1) A total of 73 primers were screened on the accessions and 24 primers produced clear repeatable amplification.From those,16 primers were polymorphism. A total number of 86 alleles were obtained in 16 polymorphic primers. The polymorphic bands were ranged from 2 to 8, averagely 5.5 and the product size was from 100bp to 230bp. The PIC values were ranged from 0.3572 to 0.8744. There were 10 high polymorphic primers for PIC＞.5. The results showed the cpSSR primer can be transferde to Musa.(2) According to the result of the 16 polymorphic primers for 42 banana accessions, the UPGMA dendrogram divided the banana accessions into three main groups based on the similarity coefficient 0.76. Group I included all the subspecies of M.acuminata and all the cultivated banana varieties. All the materials of M.balbisiana formed GroupⅡIn groupⅢ,it included all the wild materials except the species/subspecies of M.acuminata and M.balbisiana.The results showed that it was a useful tool to distinguish the related species of Musa.(3) To further demonstrate the genetic variability of the SSR loci, sequence comparison of cross-species/genus amplicons generated by four SSR loci (wctll, wct22, ccmp2, ccmp5) for 42 accessions was done. In general, in/dels, transitions and transversion were found at the four loci. size variation at the SSR loci was found especially in the inerspecies banana materials. There were quite difference at the base level when comparing M.acuminata and M.balbisiana to the other Musa species/subspecies.