F1progeny of ‘ruby seedless’בhongqitezao’developed and selected using embryo-rescue and moleclar markers

Abstract

Seedless grapes play an important role in fresh food and dry production. New varietiesbreeding by hybridization with seedless varieties as female parents is the most effective way to cultivate seedless varieties. However, the embryos of seedless varieties cannot develop normally, so it is difficult to obtain hybrid offspring as hybrid female parent. Moreover, grape is a perennial tree species with highly heterozygous genes, with long breeding cycle and low efficiency. In this study, embryo rescue techniquewas usedto cultivate hybrid offspring by crossing with ?Ruby Seedless? as female parent and ?Hongqitezao? as male parent, so as to solve the problem that seedless varieties cannot be female parent; and molecular markers technologywas usedto carry out assisted breeding research to solve the problems of long cycle and low efficiency.TP-M13-SSRtechniquewas used to carry out authenticitybreeding. SCAR marker SCF27 was used to detectthe seedless traits of hybrid plants, phenotypic traitswas used to verify the results of molecular markers, and seedless trait-relatedSSR markers VMC7F2, VrSD10 and P3_VvAGL11 was used to detect and verify the genotypes of individual plants with inconsistent detection resultsby the two methods.Theresults showed that a total of 384 hybrid offspringwere finally obtained, and the hybridization rate was 84.43%.The seed phenotypes of 163 fruit-bearing plants were identified, and the coincidence rate of genotypic and phenotypic analyses was 95.71%.Additionally, 305 F1plants were detected using the SCF27marker, and the abortion rate was 64.92%.This study shows that embryo rescue is an effective method for breeding seedless grape cultivars, and the application of molecular markers could facilitate the early identification of hybrid traits, and improve breeding efficiency.