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As the world's most populous rice edible food crops, with its output directly affect world food security and stability, while the rice blast disease as the most important one, every year a large number of rice production. How to effectively control this disease has been widespread concern researchers. From a long-term sense, breeding resistant varieties is the most effective way to combat one blast. With the continuous resistance gene cloning, using traditional methods or transgenic technology can effectively aggregate multiple resistance genes to specific material, breeding new varieties of broad-spectrum resistance. So far, have been reported from rice and its related species cloned 18 blast resistance genes, cloning these genes breeding new resistant varieties will make a significant contribution. This article is to understand 36 rice breeding material in the distribution of rice blast resistance gene were designed 11 pairs of primers detected eight blast resistance gene in the test material distribution, combined with field nursery resistance spectrum, aimed provide ideas for the breeding. Meanwhile, the use of nine pairs of primers for these materials Resistance Gene (RGA) were clustered by the above test to try to understand the disease resistance of the tested materials, distribution of resistance genes, resistance genetic diversity, specifically The results are as follows: Through seedling resistance spectrum detected, LTH valley to the test 70 Blast Isolates were expressed as susceptible, R557, Minghui 63, R9311 for detecting strain resistance is poor, anti- disease frequency in about 40%; 18B, Chuannong 1B, Chuannong 4B, Valley B is the highest frequency of resistance, reaching more than 90%; resistance of other materials were mixed, but the maintainer average resistance of high frequency on restorer material. Natural neck blast disease nursery tune the results show that each of the materials, blast incidence varies, neck blast rate at 2.78% -100%. Chuannong 4B, Valley B, anti-Hui 1, R1088 and other materials, blast resistance is higher, while gold 23B, Minghui 63 other blast resistance is poor, LTH Valley with D62B blast resistance also worst. Based on seedling leaf blast blast resistance phenotype cluster analysis shows that when Euclidean distance is about 2.3 when Chuannong 1B, 4B and Chuannong Valley B is aggregated into a class; when Euclidean distance is about 4.158, most The maintainer and restorer lines were aggregated into each category, this result shows that maintaining and Maintainer Lines close genetic relationship between materials, restorer inner kinship between the various materials versa; while D62B with the negative control Lijiang New LTH's disease phenotype very close. Through 11 pairs of primers detected eight blast resistance gene discovery, Pid3 the tested materials are present, only the R727, R498 and R137 contain Pizt genes. Pid2, Piz, Pikm, Pib, Pi-tα and Pi5 other six genes in 36 frequency of occurrence of the material were: 25.00%, 33.33%, 36.11%, 6.67%, 0.56%, 44.44%. R727, R498, R137 and JR71 these four materials with which the five genes, respectively; Mianhui 725, R9311, Zhenshan B, Ⅱ-32B, 23B which six gold material contains only Pid3 this one gene, other materials contained The number of genes to be detected ranging from 2-4. 9 with the design of primers for the test materials of all RGA-PCR analysis showed amplified polymorphic bands, each of the primers of each material individually amplified bands of 593 bands were amplified polymorphic bands of 462 polymorphic frequency of 85.71%. Primers amplified bands XLRR largest number of 104; while N1 primers amplified polymorphic bands at least, only 32; primer amplification product polymorphism best Pt. For rice lines, the Mianhui 725 in all primers worst polymorphic bands amplified at least the total number of bands, only 182. Cluster analysis further found that: different primer get different clustering results, which reflects the genetic background of the tested material differences. Clustering results showed that all the materials are divided into two categories, the same display Mianhui 725 genetic differences with other materials is greater. RGA-PCR amplification results based on cluster analysis, also tend to remain there and restorer lines were clustering phenomenon.
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