Comparative Analysis Of Structural Organization And Evolution Of Chrysanthemum And Ajania Chloroplast Genomes

Chrysanthemum morifolium is originated in China,is one of China's top ten flowers,has a long history of planting and a very important position.Chrysanthemum plays an important role in the Chinese poetry culture and flower industry,the genus Chrysanthemum has many species and related genus,which have many excellent traits for breeding.It is necessary to distinguish the species truly.With the rapid development of high-throughput sequencing technology,genomic data can be obtained quickly and cost lessly.The genome of the chloroplast is conserved and small.The prupose of this study was to determine the chloroplast DNA sequences of some species in the genus Chrysanthemum and the genus Ajania,and to analyze the evolutionary sequences of the tested sequences to study their evolution.The exact classification of the genuses provides a theoretical basis for the future breeding.The main conclusions are as follows:1.We compared three methods to extract the chloroplast DNA,and got a more effective and rapid method,which is using conventional chloroplast DNA extraction method to extract chloroplasts,and then using kit extract chloroplast DNA.The chloroplast DNA was extracted successfully from ten species of Chrysanthemum and Ajania genus.2.After sequencing of the Chrysanthemum and Ajania chloroplast DNA,the structural analysis was carried out.The results showed that the difference was little between the genus Chrysanthemum and Ajania.The genome size of the genus Chrysanthemum and Ajania was very similar,which was about 151,000 bp.All of these species contained the same set of coding genes,including 113 genes,of which 17 genes were in the IR.There are 80 coding genes,4 ribosomal RNA genes and a complete transporter protein coding gene,including 29 transport genes.These data showed that the sequences of the chloroplasts DNA are highly conserved.3.The changes of the length of chloroplast genome were due to the contraction and expansion of the IR region,and ycfl plays an important role in the length of IR region and was a significant negative correlation with the length of the IR region.The results showed that ndhJ-ndhK,trnT-trnL,rps16,ycfl,trnK and rbcL,petB-petD,rps16,ycfl genes and their surrounding areas were found in the genus Chrysanthemum and Ajania,Which are regions with high mutation rate,which are regions with fast evolution rate.The phylogenetic analysis of chloroplast genome sequence using complete sequence of chloroplast genome was carried out.It was found that the genus Chrysanthemum and Ajania were not separated clearly.