Resistance Genetic Analysis And Identification Of Tomato Spotted Wilt Virus In Yangling,Shaanxi

Tomato(Solanum lycopersicum)is one of the largest vegetable growing areas.Tomato spotted wilt virus(TSWV)is a widespread worldwide disease that can occur in greenhouses and open fields.When the disease occurs,the yield and quality of fruit will be seriously reduced.Therefore,resistance to tomato spotted wilt breeding has become one of the main targets in tomato breeding.Because of the geographical differences,the types of virus,complex relationship.This study analyzes the identification of the gene structure of tomato spotted wilt virus coat protein in Shaanxi Yangling area,the resistance identification of selected susceptible materials and M82 resistant materials H149 was used to construct genetic population and analyze the genetic resistance model,using SSR markers mapping of tomato spotted wilt disease resistance QTL,in order to Tomato spotted wilt resistance breeding guide.The main results are as follows:1.Identification of tomato spotted wilt virus in Yangling.Through field observation of 4suspected phenotype acquisition tomato spotted wilt susceptible materials,molecular identification of PCR.Of which 2 samples were amplified to 234 bp TSWV specific bands,and the sequence of Gen Bank TSWV sequence similarity reached more than 98%,indicating that these 2 materials were carrying TSWV virus,named TSWV-YL isolate,homologous cloning of coat protein gene TSWV-YL(CP),obaining 757 bp amino acid sequence.Sequence and Genbank board Book number(FR693089.1)of the highest homology is 99%;TSWV-YL-CP has a transmembrane structure located between 95～122bp;phylogenetic tree showed that TSWV-YL tomato isolate and pimiento TSWV isolates in the same branch,the closest relationship.2.Screening of tomato spotted wilt resistant germplasm.The 154 tomato samples were investigated to obtain 14 resistance materials,including 3 ordinary tomatoes,11 cherry tomatoes;using sw-5-2 co dominant SCAR markers for molecular identification of 14 resistant materials,including 3 materials containing sw-5 specific band of 574 bp and other 11 materials although the performance in the fields But the resistance,and the detection of 574 bp specific bands were detected in 14 samples;using SSR markers linked to sw-7,not detected bands,were screened in the field of resistant materials may contain other or new resistance genes,further mining firm.3.Identification of resistance to tomato blight and evaluation of resistance to germplasm.In the field resistant germplasm,H8 containing sw-5 resistance resources,and H149 with sw-5 and sw-7 linked markers were not detected,and M82 of susceptible material,TSWV-YL was inoculated by artificial friction when the seedlings were 6 slices of true leaf,and H8 artificial inoculation was 4.41 and high resistance;H149 artificial inoculation was 3.8,too.It was characterized by high resistance;M82 artificial inoculation was 67.91,showing high sensation.4.Tomato spotted wilt disease resistance genetic analysis.To filter out the susceptible materials M82 and H149 were resistant to construct genetic groups,analysis of P1,P2,F1,F2,artificial inoculation,relationship through the distribution parameters and genetic parameters,using SEA software to estimate the genetic parameters of tomato spotted wilt disease resistance trait,the trait was controlled by two major genes the additive effect,The main line with two of additive dominance epistasis major genes plus polygene model(MX2-ADI-ADI).The heritability,genetic main gene F2 generation rate is 69.65%,polygene was 10.22%,indicating that the combination of characters is mainly affected by major genes.5.Tomato spotted wilt resistance gene QTL location.To filter out the susceptible materials M82 and H149 were resistant to construct genetic groups.A genetic linkage map containing 140 marker loci was constructed by using SSR markers.The linkage map was constructed,the average spacing between markers was 49.75 c M,the minimum genetic distance between markers was 2.05 c M,and the largest genetic distance was 91.59 c M.3 QTL loci,two of which were located on chromosome 3,one on chromosome 5,and 4.6%,5.3%,4.9%,respectively.