Screening And Identification Of Cherry Tomato Germplasm Resistant To Yellow Leaf Curl Virus Disease

Cherry tomato is a kind of fruit vegetable with good economic value and nutritional value.Diseases are the main factor restricting the production of cherry tomatoes.In recent years,the prevalence of tomato yellow leaf curl virus disease has brought great losses to production.Molecular marker detection can quickly screen materials containing yellow leaf curl virus disease genes,and combined with field agronomic traits investigation,the breeding process can be greatly accelerated.This study screens the segregated materials and inbred lines of cherry tomato by using molecular marker detection,combined with the investigation of agronomic traits and fruit quality,aims to screen good parent lines with various disease resistance genes such as Ty.Further preparation of hybrid combinations,comparative test of variety of hybrid combinations is carried out to lay the foundation for the breeding of "three good" cherry tomato with good taste,good appearance and good planting in the future.1.Screening of segregated materials of cherry tomato: In the autumn of 2020,111 cherry tomato segregated materials were screened by molecular marker detection and field traits investigation,and 12 excellent separation materials such as 202WY21,202WY36,202WY48 and 202WH13 were selected,among which 5 materials contained Ty gene.In the spring of 2021,48 cherry tomato segregated materials were screened,and11 excellent segregated materials including 20WY1-1S-1,20WH3-5S-1G,20WH10-1S-3,20WH17-1G-1,were selected by individual selection and bulk-population selection methods,of which 3 materials contained Ty genes,which could be used as key diseaseresistant materials for further breeding in cherry tomato.2.Identification and selection of inbred lines of cherry tomato: 259 inbred lines were subjected to molecular marker detection and agronomic traits investigation in the autumn of 2020,and 35 inbred lines performed well.There were 83 materials containing 4 or more disease resistance genes;202TQY47,202TQY48,202TQY49,202TA60,202ZYY9 and 202ZYY43,which contained 6 disease resistance genes;202ZYY5 and 202ZYY15 contained 7 disease resistance genes.There were 34 homozygous materials for Ty-2,19 homozygous materials for Ty-1,17 homozygous materials for Ty-3/3a,7 materials contained Sw-5-2 resistance genes,202ZYY13 contained homozygous Ty-1,Ty-3/3a,Sw-5-2,which could be used as key materials for disease resistance breeding.202TA42,202TA46 and 202TA48 contained Ty gene,soluble solids content was higher than 8.5% in these lines.In the spring of 2021,273 inbred lines were planted,and 40 inbred lines performed well.The inbred lines with heterozygous Ty-1 gene identified in the autumn of2020 were further identified for individual plants,and 10 materials with homozygous Ty-1gene were screened out.The soluble solid content of 47 materials was higher than 8.5%,of which 8 materials including 211TA41,211TA45,211TA46,211TA49 contained Ty gene.The inbred lines were identified and selected for two consecutive seasons,Lu1,LY2,LY13,TA4,TA24,TA46,TA48,TA58,ZYY6,ZYY11,ZYY13,ZYY15 and TS71 performed well in the two seasons.3.Screening of hybrid combinations of cherry tomato: In the autumn of 2020,14 combinations were involved in the comparative test of hybrid combinations,202ZJ2,202ZJ7,202ZJ8 and 202ZJ14 performed well,of which 202ZJ7,202ZJ8 and 202ZJ14 contained Ty gene.In the spring of 2021,17 combinations participated in the comparative test of hybrid combinations.211ZJ11,211ZJ20,211ZJ25,211ZJ31,211ZJ34 and211ZJ40 performed well,of which 211ZJ11,211ZJ20,211ZJ25,211ZJ34 and 211ZJ40 contained Ty gene.