Evaluation and QTL Analysis for Crown Rot Resistance in Wheat
|School||Nanjing Agricultural College|
|Keywords||wheat Crown rot seedling resistance identification QTL disease discipline|
Fusarium graminearum is one of the major pathogens of wheat which can result in devastating economic losses to wheat production. Fusarium can cause two major wheat diseases:Fusarium head blight and Crown rot.. Deployment of CR-resistant varieties is the most economical measure in controlling wheat diseases. Therefore, it is the main contents of research on the incidence of genetic methods to the existing screening wheat germplasm for resistance, the resistance QTL and identify closely linked molecular markers will deepen the understanding of crown rot of wheat.The research is very significant for it will also help to prevent of the disease, breed of resistant varieties, improve the efficiency of breeding for disease resistance.In this study, wheat germplasm was screenes using previously reported wheat crown rot resistance screening methods.Furthermore, this study also optimized the screening and identification methods on that basis. The result showed that the best method of resistance identification is cotton balls inoculation method. After a preliminary screening of germplasm resources in 60 varieties of domestic provinces and cities and 22 varieties of imported wheat germplasm resources,there is no variety which the crown rot disease index <10 with highly resistance.13 materials disease index of 10.1 to 20, accounting for 15.8%. Disease index between 20.1 and 30 of the 51 materials of a sense resistance accounting for 62.1%. Disease index> 30.1 had a high sense of material 18, accounting for 21.9%. And wheat germplasm of the crown rot and Fusarium head blight resistance of the correlation coefficient was r=0.24 only.212 SSR markers were used to analyze the RIL generation of Sumai 3×Baimian 3 and 241 SSR markers were used to analyze the RIL generation of Yangmai 158×CI12633 in 2008-03 and 2008-10 respectively The experiment was desighed randomized block,two replications were set. Wheat seedlings inoculated with Fusarium graminearum cotton balls with F15 spores at the concentration of 105 spores/ml., identified the Crown rot index after 30 days. The analysis of incidence of disease index of the two groups showed normal distribution. The incidence of the two groups inoculated quarters were 0.84,0.76 correlation coefficient between two runs. Mixed linear model approach based on the mapping software Joinmap3.0 and MapQTL5.0 data analysis. QTL mapping results show that the experiment in 2008.3, the two groups in the three chromosomes were detected QTL trairs, the average degree explained 11.3%-13.8%; in 2008.10 experiment,3 QTLs were detected in Sumai 3/Baimian 3 generation explained 8.9%-14.7%, and 4 QTLs were detected in Yangmai 158/CI12633 generation explained 10%-12.5%. Comprehensive two experiments, in CI12633/Yangmail58 group 4B,6B,7D, and Sumai 3/Baimian 3 groups of 3B,5D,6B, 7D chromosomes found in Crown rot resistance QTL, of which 6B chromosome QTL in the two populations were detected and stable. These detected QTL with resistance to Crown rot in the group of scab resistance QTL detected in different chromosomes, and indicated different.anti- mechanisms between Crown rot and FHB.Furthermore,this research carried out relevant research, including the relationship between wheat sharp eyespot and crown rot. Fusarium graminearum with GFP infection approaches was observed.