Mapping The Resistance Gene Ve And Development Of Linkage Markers To Potato Verticillium Wilt

The potato(Solanum tuberosum L.)is widely liked by consumers because of its can be used grain and vegetable and comprehensive nutrition.Compared with other food crops,the potato has high economic benefits and has a large area for planting;However,in China,its yield is not high,and there is a big gap compared with developed countries.For this reason,diseases are one of the most important causes of potato production.Potato Verticillium wilt is a fungal disease that seriously affects potato yield and quality.Excavating disease-resistance resources,locating disease-resistance genes and developing linkage markers can speed disease-resistance breeding.And breeding disease-resistant varieties is one of the most cost-effective ways to prevent diseases.But so far,there are few studies on the resistance genes of potato Verticillium wilt,and there is no report on the location of resistance genes.In this study,diploid potato interspecies hybrid C545 was used as the parent of resistance,and the backcrossed BC1 group of susceptible parental V67 was used as material.The following main results were obtained:1.BC1 group phenotype identification: Randomly select 172 group offspring,After several rounds of phenotypic verification experiments,the phenotype identification of the group material was completed.2.BSA+DNA-seq analysis of extreme materials: Twenty-four disease-resistant materials were selected to form a disease-resistant mixed pool,Thirty susceptible materials were set up to form a susceptible pool and the whole genome was sequenced.The sequencing depth was 30 x.28.46 Gb and 26.39 Gb data were obtained respectively.The bioinformatics analysis was used to draw the average Δ(SNP-index)distribution map of resistance and susceptible pools.And the disease-resistant locus was predicted to be located on chromosome 5 at 0-6.3 Mb by the distribution.3.Development of linkage markers for major effect sites: Based on the 0-6.3 Mb disease-resistant locus on chromosome 5 predicted by the distribution map,278 pairs of gene markers primers and 329 pairs of CAPS markers primers were designed.A total of 6gene markers,1 Indel marker,and 5 CAPS markers were developed through the verificationof the resistant and susceptible parents and offspring.A total of 69.4 cM linkage maps were mapped using these 12 markers and population phenotypes.However,all 12 markers were on the side of the disease resistance locus,and the disease resistance locus was located after4.7 Mb chromosome 5.4.Mapping of Ve gene: The bioinformatics prediction interval and marker-targeted interval were integrated,and the disease resistance site was located within the range of 1.6Mb between 4.7 Mb and 6.3 Mb.Unlike previous reports on the resistance to Verticillium dahliae located on chromosome 9,this study identified a new site for potato resistance to Verticillium wilt for the first time.This site is located on the front of potato chromosome 5.The study on the genetic localization of potato resistance to Verticillium wilt extended the idea,and laid the foundation for the cloning of potato resistance gene to Verticillium wilt.The development of the linkage markers provided a powerful help to potato breeding for resistance to Verticillium wilt.