| 'Jingyou' grapevine is used as experimantal materials, which was treated using ABA and ethephon with different concentration. The effect on maturation and fruit quality of grapevine with different concentration was studied. Real-time quantitative PCR was used to study the effects on the mRNA transcriptional level of 14 structure related genes of anthocyanin biosynthesis and 2 regulating genes. The GST genes related of anthocyanin accumulation was cloned and carried out transcription characteristics annlysis. The results are as follows:1. The results indicated that treatment with ABA and ethylene both play a positive role of fruit softening, degradation of organic acid and accumulation of anthocyanins. The effect of berry softning with ethephon was superior to that with ABA, but the effect of soluble solid accumuclation with ethephon was weaker than ABA.2. The results of treatment with different concentration of ABA and ethephon indicate:the optimal plant growth regulator treatment of accelerating fruit maturation is 600 mg/L ABA, this treatment allowed grapes to be harvested 13-16 d before nontreated fruit, and attained marketable quality;300 mg/L ABA and ethephon were higher than the control treatment, but the effect of accelerating maturation is not obvious, which only allowed grapes to be harvested 3-5 d before nontreated fruit; the treatment of high-level concentration of ethephon (900 mg/L and 600 mg/L) also advanced ripeness of fruit, but the treatment caused the phenomenon of uneven pigmentation, serious fruit cracking and fruit drop.3. The principal relatd genes of anthocyanin synthesis in the flavoniod pathway, such as CHSs, CHIs, F3Hs, F3'H, F3'5'H, DFR, LDOX, UFGT, OMT, GST and transcriptional factors(MybA1, MybA1-2) were up-regulated transcribed, which also played a critical role on anthocyanin accumulations at veraison period. The transcription of CHS2, CHS3, CHI1 and F3H2 is closely related to the anthocyanin synthesis in gene families of CHSs, CHIs and F3Hs. Besides, UFGT, GST, MybA1, MybA1-2 were transcribed in great quantity with anthocyanin synthesizing.4. The treatment with ABA and ethylene enhanced the transcription of anthocyanin synthesis related genes, which accelerated transcribing earlier and enhanced quantity of transcription. Both ethylene and ABA promoted the genes transcribing distinctly, especially OMT, UFGT and GST. However, the regulation on CHSs, F3Hs, DFR, LDOX treated by ethylene was weaker than those with ABA treatment.5. Correlation analysis of influencing factors and anthocyanins demonstrated that the the content of soluble solids of berry, the genetic transcriptional level of some anthocyanin biosynthesis genes and transcription factors were positively correlated to the content of anthocyanin; Content of titratable acid was negatively correlated to the content of anthocyanin; The genetic transcriptional level of CHS2,F3H1 was no correlated to the content of anthocyanin.6. A full-length GST gene named VJyGST was cloned with RT-PCR and RACE technology from Jin You grape. The Genbank accession number is GU370062. VJyGST is 851 bp in length and contains a 642 bp ORF, encoding a predicted polypeptide of 213 amino acids. The predicted isoelectric point of the protein is 5.52 and molecular weight is 24.25 kDa. The amino sequence of VJyGST has the homology with GST of Vitis amurensis, Citrus sinensis and Litchi chinensis, and the likeness coefficient is 99%,77% and 67%, respectively.7. Real-time-quantitative PCR analysis showed that GST gene was mainly transcribed in skin, and faintly transcribed in flesh. Particularly, during the anthocyanins accumulation, the transcriptional level of GST in skin increased progressively and reached a peak at the 90%-colored. The result demonstrated that the transcriptional level of GST has a certain correlation with the accumulation of anthocyanins. |
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