Ssr Markers In Wheat Genetic Diversity Research

At present,global breeding resources are speeding to decrease.The severe decrease of biological diversity not only makes the work of quality improving more difficult,but also weakens the ability of the crops to adapt to the environmental threaten.Therefore,to research and protect wheat genetic diversity becomes quite significant.So far,people have already carried out the research and improvement on the levels of morphology,biochemetry and molecule.Wheat is the most important commmodity and tactical food supplies in China.It can be used as raw material of many kinds of staple and non-staple foodstuffs.Wheat produce concerns the food safety of 1,600,000,000 Chinese in 21st centrury.Since the world food safety is under urgent situation,sufficient wheat basic research,from some angels,administers to stablize world food supply.To study wheat genetic diversity rebound to the collection,evaluation and conservation of wheat germ plasm and the selective breeding in wheat crossbreed.Genetic diversity is an important component of diological diversity.The more abundant inner-genus genetic diversity is,the stronger the commodation to environmental changes is,and the greater the contribution of breeding is.The non-scientific development of modern breeding technology,geneticloss of crop variety severely reduce crop genetic diversity,limited inheriting base confines the further improvement of crop output and quality,at the same time,aggravates the fragility of crops confronting biological and non-biological environmental threat.The expression of genetic diversity is realized through the recombination or modification of large quantities of genes.Only by full comprehension of genetic diversity,can make innovation of germ plasm and crop improvement purposful and contribute to the development of the human world.By the research on crop genetic diversity,we can provide theological foundation for the sampling of crop genetic resources,the category establishing core germ plasm of inheritant resources,we can speed up breeding progression and bring foodstuff producing to the track of more scientific and sustained development.To summarize,it is essential to make an integrated research on wheat genetic diversity in China.Presently,the genetic diversity investigation can proceed with agriculture amount character,biochemical markers and molecule markers which can directly examine DNA.Molecule markers are a kind of newgenetic markers which discriminate material directly by check the sequence mutation of DNA alkali radical.SSR with a high degree of polymorphism,codominance,taxological focus,good stability and easy technology is a sort of pretty useful molecular markers and has been broadly applied in gene mapping of animals and plants,study in system growth and genetic diversity,species and genes identification,the making of target genes and OTL,etc.Thus,I will adopt this molecule marking to study the diversity of wheat resources.This research tries to apply molecule biological technology,SSR molecule marking technology,to analyse the genetic diversity of 60 wheat samples from ten different ecological zones of our country.Thus it can supply referent information and theological foundation to wheat breeding.This experiment filters the SSR location on wheat chromosomeon the basis of DNA sequence data,then design a pair of specific introduction according to the high conservation of the sequence of SSR's two sides,apply these introductions to broaden those 60 SSR sequences,after that,apply electrophoresis and coloring, at last,we can get the multi-morphology information of certain SSR location.This experiment utilizes 23 pairs of SSR to get 96 different sizes products,each pair of SSR gets 4.6 products.There into,the most productive and clear products locate on xgwm499,xgdm98,xgwm334,xgwm186 on 5A,6A,6D chromosomes,among these,6A takes on 19.The experiment results prove the show the acurate of this method. They also show that SSR markers are indeed a kind of valid molecular markers to make a research on wheat germplasm.The results testify that local varieties of wheat in China are extremely rich in genetic diversity,the GD values range from 0.261-1.256, among them,No.39 winter wheat (head fire) and 40 (head monk)producing in the middle and lower reches of Yangtze River have minimum genetic distance between species;The largest GD value appears between the wheat and White Wheat Varieties from Liuzhou.Meanwhile.the23 pairs of SSR used in this experiment can ifferentiate the 60 samples,and the breeds from major ecological zones do not get together.