Separation Identification Of Pyrenophorateres And Association Analysis Of Barley Germplasm For Resisting Barley Net Blotch

The barley net blotch is one of the most usual barley diseases. In recent years, barley net bltch occurs and becomes popular in barley productin region of our country. It not only can restrain natural growth and development of barley, but also can make barley yield lower and make quality worser or have no harvests. The barley net blotch is becoming so popular,the major reasons is that our country is short of germplasm resources of resisting barley net blotch. The experiment mainly study below three faction about barley net blotch. Firstly,collecting susceptible barley leaves, isolating and cultivating Drechslera teres(Sacc.) Shoem.Secondly, using the pathgeon to evaluate resisitance of different sources barley cultivates.Thirdly, using the SSR molecular markers to explore preliminarily the resistant genes of barley net blotch. The resultst are as follows:1. According to studying, we can get 9 pathgeons of Drechslera teres(Sacc.) Shoem,they are P.teres f.teres.. The LQA has the highest pathogenicity in 9 different strains, and makes the barley cultivar Meidingxiangganguo badly susceptible.2. Using the spray-inoculation to evaluate resisitance of 89 barley cultivars, the result indicates: the disease resistance of different cultivars have great difference, disease index of89 cultivars is between 34.67~96.32. There are two cultivars to behave resistant-moderate resistant, disease index of two cultivars are respectively 31.67 and 33.56. The cultivar ZD02732407 is moderate resistant, disease index is 45.22.There are fourteen cultivars to behave moderate resistant-moderate susceptible, moderate susceptible cultivars have the same number. There are fifty cultivars to behave moderate susceptible-susceptible. There are seven cultivars to behave susceptible, Including cultivar Meidingxiangganguo, its disease index is to reach up to 96.32.3. 70 pairs of SSR markers were used to detect the diversity of 89 barley materials. A total of 312 alleles were found, and the average alleles per locus were 4.45, which ranged from 2 to 10. Allele frequency varied from 0.012 to 0.988, the marker scssr15864 has the highest allele frequency, the marker Bmac40 has the lowest allele frequency. The polymorphism information content(PIC) value ranged from 0.0985 to 0.8846. The gene diversity was from 0.1039 to 0.8944.4. When the genetic similarity is 0.667, 89 cultivars are divided into two groups, group one has 22 cultivars, group two has 67 cultivars, the genetic similarity of the all group isfrom 0.520 to 0.873.The genetic similarity of MEI 44/I and MEI22/I is the highest, it is0.873. The genetic similarity of Z145V020 W and huangmang barley is the most small, it is0.520.5. Through analysis on the population structure, it could be divided into two subgroups of inbred lines.population structure is the basic of association analysis. Five markers are found to associate with barley net blotch resistance under GLM, and the rate of phenotypic variation explained ranged from 7.2% to 42.43%. There are two SSR marker showed significant association with barley net blotch resistance(P<0.01) with the rate of phenotypic variation explained by 10.75% and 42.43%。...