Project description:According to the field observation result, the grafting treatment used in this study was found that 101-14MG rootstocks grafted with Crimson Seedless had a positive influence on fruit coloring. Combined metabolomic and transcriptomic analyses were conducted with different treatment grape of own rooted Crimson Seedless cultivar, and grafted 101-14MG, 110R, SO4 rootstocks with Crimson Seedless cultivar. Peonidin 3-O-glucoside, Delphinidin 3-O-glucoside, Cyanidin 3-O-glucoside, Malvidin 3-O-glucoside, Petunidin 3-O-glucoside were identified as the pigments responsible for the purplish red color peels. The results showed that the grafting material of rootstock 101-14MG could promote the accumulation of anthocyanins in grapefruit in advance. Transcriptome analysis revealed the anthocyanins biosynthetic related genes from the upstream (phenylalanine ammonia-lyase) to the downstream (anthocyanidin 3-O-glucosyltransferase, anthocyanidin synthase) were almost upregulation during anthocyanins increased. However, all these genes were highly expressed in samples G715 (Crimson Seedless/ Crimson Seedless), suggested that self-grafting rootstocks might have an earlier response to fruit color-related metabolism. A transcription factors-scale protein interaction (PPI) analysis showed that MYB4, MYB44, MYB80, and dead-box RNA helicases might be the core regulatory genes. Our results provide global transcriptional changes in grape peel color regulation under different grafting conditions for improving the breeding process.