Analysis Of DNA Methylation In Different Chrysanthemu Mand Different Organization

Making full use of molecular marker technology to identify chrysanthemum varieties is basis ofgermplasm conservation and breeding. DNA methylation is an important DNA modification and plays animportant role in the regulation of gene expression. In the process of plant growth,CCGG sites often occurs5-mC changes, thereby regulating gene expression. This study analysed12varieties of chrysanthemum ofKaifeng of China on genetic and epigenetic diversity by using AFLP and MSAP markers techniques. At thesame time, taking the leaves,feet buds and petals to indentify metylaion on CCGG sites. The results of twomolecular marker technologies were compared. The main contents are as follows:Using AFLP marker technology analysed12varieties of chrysanthemum on genetic diversity.Wereceived a total of306bands by6pairs of primers, average51each pair of primers. Polymorphic bands ofeach pair of primers percentage from53.7%to77.2%,6pairs of primers were found polymorphic loci208accounting for67.9%of the total band. It Proves AFLP applied to the identification of chrysanthemumvarieties is high polymorphism and DNA sequences are quite differentin varieties of chrysanthemum.The MSAP results showed that different chrysanthemum varieties total methylation level isinsignificant, about20.1%to26.1%.DNA all methylation rate in the range7.7%to13.7%.There are manychange of methylation type in different organization. Four pairs of primers are highly polymorphic, andthey can distinguish between different varieties. Compared with AFLP,MSAP is Lower polymorphism. Itsuggests that MSAP can be used for the identification of the varieties of chrysanthemum, as well as MSAPis more suitable for DNA methylation identification in similar genome sequence but differentphenotypically or different parts in same species.There are three types methylation changes in different organization. Type A is demetylation, Type B isdenovo methylation,Tpel C is irregular changes. From foot bud to flower, the number of DNA denovomethylation is fewer than demethylation,it lead to the demethylation.The changes of DNA methylatinmaybe regulate gene expression, and finally decided to plant growth and development and organdifferentiation.