Studies On AFLP Analysis And Classification Of Musa

Bananas (Musa spp) have a complex origin and a long-term of being cultivated all around the world. A common problem confronting banana taxonomists and horticulturist in selecting and utilizing is the homonym and synonym caused by different languages and dialects of different region (country).The current system of classification and evolution route research of banana is suggested by Simmonds and his co-workers in 1955, which based on the morphological characters. Little wild germplasm was included in fomer Moleculer level studies in Musa. Some central Musa (including 46 cultivars and 14 wild species) were tested using AFLP molecular markers with two pairs of primers (E-ACC/M-CAT and E-ACC/M-CAG). One aim of this research is to ascertain the relationships between wild species and cultvars, cultivars belong to the same group in Simmonds system. Another aim is to provide molecular basis for Musa systemetics and banana evolution route research. Moreover, this research is attended to give some help for conversation, utilization, and identification of Musa germplasm and to provide some theoretical basis for classifying several disputable germplasm.The main result is listed as follows:1. The materials showed abundant polymorphism based on molecular level and the wild germplsms have less polymorphism than the cultivars. The number of polymorphic bands varies from 37 (Hekouyebajiao) to 58(Longxuan,Huanong No 7,Heijiaomang), while the ratio of it is from 28.03 to 43.94 percent. 132 polymorphic distinct bands were obtained with two pairs of primers in this research, which is enough to distinguish the 60 materials from each other.2. Based on the AFLP data, the tested materials were clustered into four groups on coefficient level 0.62. Furthmore, on the higher coefficient level, the individuals in each group are sorted into subgroups. By the selected amplification results with one pair of primer, the wild germplsms were efficiency distinguished. The traditional classification of Cavendish subgroup based on caudex height is not strict corresponded with gene type similarity.3. Upon the AFLP data, the phillippine plantain "Saba" was clustered into "ABB" group. Two homonyms were identificated (Xiaomijiao, 63-1 respectively). Diaoluoaijiao and Beida'aijiao No.2 are probably the same cultivar (synonym).4. It's better to use two pairs of primers or more to analysis for distinguishing individuals with very close relationship. And, it's necessary to associate with traditional classification system in this kind of work.5. By and large, the classification of the tested materials is consistent with Simmonds system, but to ascertain the position of some individuals need more studies.