Genetic Diversity And Genetic Structure Of Chinese Chestunt By AFLP Analysis And The Establishment Of Database About Varietal Resource In Chestnut

Chestnut (Castanea mollissima Blume) is one of the most important trees that are indigenous to a large area of China and have long been cultivated,and is characteristic fruit tree in China, which can be found widely in northern and southern China.Genetic diversity and population structures were assessed in cultivars of Chinese chestnut by AFLP (Amplified Fragment Length Polymorphism) analysis. 9 primer combinations were used , and a total of 260 bands were generated, including158 of the polymorphic bands, so the polymorphic percentage was 60.77%. Genetic distance ranged from 0.1484 to 0.9225 among cultivars, and averaged genetic diversity was found, being h=0.1895, which could fully showed that there was rich genetic diversity and higher one. Genetic diversity among populations ranged from 0.1631 to 0.1803, respectively for Beijing population and for Hubei population. The data of the relative magnitude of genetic differentiation among populations showed that the genetic variation within population was higher than that of among population, so the degree of the genetic variation among population was lower. And gene flows of 4 populations were over 2, which suggested that there existed sufficient genetic exchanges to prevent the genetic differentiation made by genetic drift among population. Meanwhile the distribution pattern among 45 cultivars was examined by spatial autocorrelation analysis, showing that the populations took on randomly distributed spatial pattern, but partial locus displayed some kind of spatial structure. The reaction system of AFLP technique that was fit for chestnut was optimized, including the proccedure of drawing DNA, DNA purification and the optimal reaction condition for AFLP. And this can be basis for further analyse the genetic characteristic of chestnut. The result showed that AFLP technique was a reliable and highly informative one. The database of varietal resource of chestnut was established via applying Microsoft 2000 in order to share resource information and to make it convenient for varietal intercourse. It included six forms of sixty-six fields, ten queries, twenty-one forms and several report forms and more than 300 varieties' information was widely collected. Meanwhile it could be viewed as a nicer ministrant flat for researchers to learn and query what they want to know about chestnut's information.