The Phylogeny Of Ainsliaea DC.

BACKGROUD AND AIMS: Ainsliaea DC. is an Asiatic genus of the tribe Mutisieae Cass in the family Asteraceae. Ranging from Afghanistan to Japan, its main distribution area is China.Botanist from many countries have made important contributions on the research of this genus.Since the publish of Beauverd's Ainsliaea ,the number of species with legitimate name (including new names and new combinations) added up to 109 nearly one hundred years, but there are a lot of taxonomic problems.In "Flora of China, " Volume 79 ,this genus has been divided into three groups only according to its leaves distribution in the stems. Such classification based on only one character are too single,and is of great artificiality. As DNA sequencing technology have improved and the molecular systematics has been made considerable progress. In this thesis, we use molecular methods to study the relationship between species of the genus and to test whether the classification system of "Flora of China" is reasonable, and to establish a more rational classification system of Ainsliaea DC.METHODS: The extraction of total DNA using DNA extraction kit (Plant Genomic DNA Kit, biomid Beijing) and improved CTAB method. ITS, psbA-trnH, matK, trnL-rpl32 four fragments were amplified using universal primers. Purified PCR products were used as template for sequencing reactions. The products were purified and sent to the system center and sequenced with the ABI PRISM 3730XL sequencer. The sequences were corrected and splicing by ContigExpress, with ClustalX version 1.83 for the bit array, and then use BioEdit (Hall 1999) for manual correction. The MP (maximum parsimony, maximum parsimony), BI (Bayesian inference, Bayesian methods) were used for data analysis.RESULTS: Four fragments were successfully amplified, most can be successfully sequenced besides the ITS sequence of A.ramosa . There are some polyA in several populations of psbA-trnH, so it need to be sequenced reversely.In the phylogenetic tree from single sequence matrix, because sequence length of psbA-trnH is shorter, the relations of most species have not been resolved, and the support rate is lower. The solution of other three segments is better, but there are still no entirely resolved.The phylogenetic tree from joint sequences can be divided into two major parts, with the corresponding geographical distribution of species correspond.CONCLUSIONS: The classification of "Flora of China" in the genus are unreasonable, it does not reflect their phylogenetic relationships. Dividing the genus into three groups only according to its leaves distribution in the stems is contradict with the results of molecular systematics. From the phylogenetic tree of these fragments, the genus can be divided into two regions, that is, Sino- Japanese region and Sino - Himalayan region.