| Wheat is one of the main food crops in our country.Sripe rust, caused by P. striiformis f. sp. tritici(Pst) occurred in our countryfrequently, caused the loss of wheat production in China, and it is a serious threat to wheat grain production safety in our country. To grow resistant cultivars is the most economic, safe and effective method to preventeand control the disease and it is also friendly to the environment. However, the strong variability characteristicswheat stripe rust, makes the new small in environment and rise constantly, lead to a large part of the popular before small kind of disease-resistant varieties under the new small toxicity kind of infection resistance "loss".The fact that lacking of effective resistance source and irrational using of resistance genes, make the most basic measure through the resistant cultivar control stripe rust cannot play its proper role.However, to find and discover new resistance sources, actively carry out the combination of new resistance genes and the current main variety work, scientific and rational use and layout of the current effective resistance genes, is still an important deployment of resistance to stripe rust of wheat breeding work and long term solution.So this research is about our country current breeding lines and small part introduced cultivation cultivars. Through seedling stage set points of different strains of wheat stripe rust was physiological races of resistance identification, into a plant a boom in the hybrid current popular physiological races of resistance identification and in Tianshui natural set into a phase of disease resistance of plants in disease nursery and through different periods and different locations of the disease resistance identification results comprehensive evaluation of the current parts of wheat varieties(lines) and main variety resistance level.Through Yr1 and Yr2 auxiliary marker determination, genetic testing system combined with effective resistance identification results, in order to establish a Yr1 and Yr2 disease-resistant gene detection system, and through the analysis and evaluation of these two genes in the current application status of wheat lines, make Yr1 and Yr2 more reasonable use, to enrich the diversity and disease-resistant varieties of wheat varieties resistance genes to provide technical means to sustainable use. At the same time, by using the known of yellow rust resistance genes in seven main effect Yr5, Yr9, Yr10, Yr15, Yr17, Yr18 and Yr26 developed reliable molecular markers for all volunteers materials for molecular detection.Comprehensive phenotypic characterization results, testing results of molecular marker and breeding pedigree to genetic analysis of the current disease-resistant cultivars, in order to make clear the resistance genes of wheat varieties to reserve in our country.From the angle of macroscopic and microscopic evaluation of China’s reserve wheat cultivars resistance level and the distribution of the resistance genes, the application of reserve wheat varieties in our country, to promote and provide guidance for the selection of improved cultivars, and for resistance to strip rust gene science, reasonable layout and wheat resistance to stripe rust prevention and control work to provide theoretical reference.This experiment to obtain the following main results:1.The establishment of molecular detection system about wheat stripe rust resistance genes can provide technical support for the efficient using of the resistance genes and gene aggregation. With Yr1 and Yr2 closely linked markers as the molecular markers, Sull-1,CYR29, CYR32,CYR33 and V26/CM42 for wheat stripe rust as identify strains, we construct Yr1 and Yr2 molecular detection system respectively. The evaluation of disease resistance and Yr1 and Yr2 gene analysis of 181 wheat high generation cultivars were carried out. The results showed that gwm372 and gwm382 could be used as Yr1 markers for detecting, and wmc364 could be used as a marker for detection of Yr2; Five differential strains could be better applied to distinguish Yr1 and Yr2. The results of molecular detection of 181 wheat cultivars showed that the ratio of Yr1 and Yr2 gene loci in the back-up varieties was very low. This suggests that these two loci have been lost in the process of resistance breeding of wheat in China.2.There were 23 local introduced cultivars and 84 high generation of wheat material from the important stripe rust overwintering regions Chongqing.The wheat materials in the region only 13(12.1%) were resistant to CYR32, CYR33, V26 / CM42 and V26 / G22 during seedling stage, including 10(9.3%) were resistant all the races in the whole stages, 12(11.2%) of the material performance into adult plant resistance characteristics, the rest 85(79.4%)without resistance to current races.Results show that the resistance of wheat in the region to the level is too low, need to plant breeders in the mining of new resistance genes and the breeding of disease-resistant varieties, contribute to the popularity of prevention and control of wheat stripe rust.3.Molecular testing of 107 wheat materials from Chongqing showed that there were 22 materials detected Yr9 molecular markers, 8 materials detected Yr17 molecular markers, 3 materials detected Yr18 molecular markers, 42 materials detected Yr26 molecular markers., among them 6 wheat materials were detectedYr9 and Yr17 molecular markersat the same time, there were 3 materials detectedYr9 and Yr26 molecular markersat the same time 6 material were detectedYr17 and Yr26 molecular markers.Only 1 was detected Yr18 and Yr26 molecular markers. There were no detected Yr5, Yr10, Yr15 molecular markers. The Yr26 resistance source was too frequently applied in the region, due to the emergence of new race which was virulent to Yr26, the potential hazards of pandemic article can lead to rust.4.Among the 448 materials from our whole country, only 37(8.3%) cultivars resistant to CYR32, CYR33 and V26 during seedling stage, 34(7.6%) cultivarsresistant all races in the whole stages; 115(25.7%), the identification performance for adult plant resistance; the rest 299(66.7%) cultivars without resistance to current races.Results showed that the resistance level of reserve wheat cultivars in our country is very low, it should increase in breeding materials, breeding quality breeding of resistant materials and resistant source materials to create, and actual production to provide security for disease-resistant breeding workin the future.5.Molecular testing of showedthe 448 materials, there are 91 wheat materials detected Yr9 molecular markers, 44 wheat materials detected Yr17 molecular markers, 20 wheat materials detected Yr26 molecular markers. Among them, there are 7 wheat materials which detect Yr9 and Yr17 molecular markers at the same time. It was only one material(GY1304) which detested Yr9 and Yr26 molecular markers at the same time. There are 6 materialswhich detectedYr17 and Yr26 molecular markersat the same time.No detected Yr5, Yr10, Yr15,Yr18 molecular markers. |
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