Study On Genetic Diversity Analysis Of Different Types Spring Wheat With RAPD

The spring wheat(Triticum aestivum L.) was the main cultivated type of wheat in north of China.Creating new character wheat of resistant drought and salt is the main objective of spring wheat breeding. It is the most efficient means and method that using the technology of biology improved the character. Using the molecular marked technology not only appraised cross varieties effectively, but also analysised genetic diversity. 22 different types spring wheat and triticale were carried through RAPD analysis and A-PAGE analysis in embody condition in order to establish the molecular marked-assisted selection system of wheat and offer the necessary technology in improving resistant character of wheat. The results showed as follows:1.There were 20 gliadin genotypes in the 22 cultivars by acid polyacrylamide gel electrophoresis (A-PAGE) analysis. 30 gliadin bands were separated by electrophoresis and 26 of them polymorphism (amount to 86.67%). The genetic similarity coefficient (GS) based on gliadin ranged from 0.005 to0.996, with an average of 0.501.It was showed that there was abundant aberrance in these varities. Cluster analysis showed that the studied cultivars could be classified into 4 clusters at the level of GS 0.501,they are respectively the spring wheat in dry land, the spring wheat in humid land, triticale in dry land and triticale in humid land. Obviously, the studied cultivars had abundant variation and high genetic diversity.2.Some problems about the repeat ability of RAPD, which include template concentration, MgCl2 concentration, dNTPs concentration, primer concentration and Taq DNA polymerase concentration were studied separately. A set of PCR system, which was fit for our lab and has a good repeat ability was obtained.There were templet DNA 25ng, MgCl25.0mmol, dNTPs 4.0mmol, primer10μmol and Thermas aquaticus DNA polumerase1.25U in this system.3.100 arbitrary primers (10-mers) were used for the PCR amplification of random genomic DNA fragments. Some 27% (amount to 27) of the primers could amplify polymorphic bands. 91 amplified bands among 156 were polymorphic. Every primer could amplify 1 to 10 polymorphic bands, with an average of 3.4 bands. The mean GS based on RAPD makers among the 22 cultivars was 0.615, with a range from 0.235 to 0.994. Cluster analysis showed that the studied cultivars could be classified into 5 clusters at the level of GS 0.618. The results showed as follows: Ⅰ:include 4 spring wheat cultivars in dry land and 7 spring wheat cultivars in humid land; Ⅱ:8360; Ⅲ: 15-3-106 and Xiaopin20-1528; Ⅳ: 1533 and two triticale cultivars in humid land; Ⅴ: triticale in dry land and triticale in humid land.4.Twenty pairs two-primer through random combined 27 arbitrary primers were used for the PCR amplification of random genomic DNA fragments. Some 90% (amount to 18 pairs) of the two-primers could amplify polymorphic bands. 69 amplified bands among 132 were polymorphic. Every primer could amplified 1 to 12 polymorphic bands, with an average of 3.5 bands. The GS based on RAPD markers ranged from 0.20 to 0.997, with an average of 0.599. Besides the majority of varieties with same consanguinity were clustered together in cluster analysis, a few of sister department varieties were divided. They were Xiaopin20-1528 and Xiaopin33-1528.It showed that the genetic variation and genetic diversity were relatively high in the studied wheat cultivars.