Abstract: The present study investigated the effects of different concentrations of ethephon on the changes of anthocyanin contents and the transcription of anthocyanin biosynthesis enzyme genes during the fruit coloring period in Jingyou grapevine by means of real-time PCR. The results demonstrated that the anthocyanin biosynthesis pathway genes, including CHSs, CHIs, F3Hs, F3′H, F3′5′H, DFR, LDOX, UFGT, OMT, GST and transcriptional factors (MybA1, MybA1-2) were up-regulated expressed at veraison. The transcription of CHS3, CHI2 and F3H2 in gene families of CHSs, CHIs and F3Hs is closely related to the anthocyanin synthesis. Besides, UFGT, GST and MybA1 were transcribed in great quantity with anthocyanin synthesizing. The transcription of the anthocyanin biosynthesis pathway genes was enhanced by ethephon treatments, which accelerated transcribing earlier and enhanced the quantity of transcription, especially GST, UFGT and MybA1. Correlation analysis of the principal related genes and anthocyanins demonstrated that the genetic transcriptional level of some anthocyanin biosynthesis genes (CHS3, CHI2, F3H2, F3′5′H, UFGT and GST) and transcription factor (MybA1) were positively correlated to the content of anthocyanin. The genetic transcriptional level of CHS1, CHS2, CHI1, F3H1, DFR, F3′H, LDOX and OMT was not correlated to the content of anthocyanins. The results of this experiment will provide a theoretical basis for further clarifying the mechanism of anthocyanin biosynthesis and application.

Key words: grapevine, anthocyanin, ethephon, gene expression