Abstract
Seedless grapes play an important role in fresh food and dry production. New varieties breeding by hybridization with seedless varieties as female parents is the most effective way to cultivate seedless varieties. However, the embryos of Seedless varieties can not 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 technology was used to 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 can not be female parent; and molecular technology was used to carry out assisted breeding research to solve the problems of long cycle and low efficiency. TP-M13-SSR technique was used to carry out authenticity breeding. SCAR marker SCF27-2000 was used to detect the seedless traits of hybrid plants, phenotypic traits was used to verify the results of molecular markers, and Seedless trait-related SSR markers VMC7F2, VrSD10 and P3_VvAGL11 was used to detect and verify the genotypes of individual plants with inconsistent detection results by the two methods. In this study, a total of 384 hybrid offspring were finally obtained, and the hybridization rate was 84.43%. A total of 163 fruit-bearing plants were identified, and the phenotypes of their seeds were identified. The coincidence rate of genotypic and phenotypic analyses was 93.88%. Additionally, 305 F1 plants were detected using the SCF27-2000 marker, and the abortion rate was 64.92%. We speculate that the inconsistent results were caused by parthenocarpy, SCF27 marker limitation, among other factors. Overall, 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.