Effect Of Trellis Systems/Canopy Types On Anthocyanin Metabolism In Grape

Anthocyanin is an important product in the secondary metabolism of grape,its content and metbolism play an important role on the quality of grape and wine.With global warming,the high temperature,strong light and other extreme weather occur much more frequently nowadays than they used to,which greatly affect the grape growth and anthocyanin metabolism.In this paper,the effects of different trellis system/canopy type on anthocyanin metabolism were discussed with Moldova grape of four year old as material.At the same time,the anthocyanin monomer of different grape cultivars in the condition of vertical trellis system(VTS)was compared.The main results are as follows:(1)Pergola(PG)significantly improved the micro-environment around Moldova fruit.In the year of 2015 and 2016,compared with the VTS,the temperature,light intensity,temperature and humidity fluctuation range and high temperature ratio of PG were significantly lower than VTS,suitable humidity ratio was higher but the high humidity ratio was lower.(2)The expending and growing of grape fruit was promoted by VTS in prophase,but PG promoted the vertical and transverse diameter's growth,the increase of grain weight and all kinds of nutrients,with the advantage of backwardness,so there was no significant difference between the two groups at maturity.In 2015,the content of reducing sugar,grain weight,total phenols,aromatic substance,anthocyanin and flavonoids of PG grape increased by 2.39%,5.34%,5.65%,16.01%,27.11% and 44.89%,compared with that of VTS.In 2016,it showed the similar trend,with a slightly difference but it was not significant.In terms of grape wine quality,PG,which increased the fruit secondary metabolism resulted the increased content of ascorbic and total phenols by 14.68% and 18.65%,respectively,compared with that of VTS grape wine,the results also showed that the PG increased the content and variety of aromatic substance of grape wine,besides,the chrome and antioxidant resistance were significantly better than that of VTS wine's.(3)During the process of fruit development,the methylated anthocyanin appeared earlier and had higher content in Moldova,but the acylated anthocyanin was a little later;the content of various monomers of anthocyanin showed a sharp rise.From veraison to maturity,the gene expression of anthocyanin synthesis and modification as well as the enzyme activity in anthocyanin metabolic pathway of PG showed the synchronicity;while for the VTS,just the relative gene expression showed the synchronicity.At maturity,13 kinds of anthocyanin monomer's content of PG showed significant difference compared with VTS,the content of c-Mv-co was 74.39% higher,meanwhile,the content of Dp-ac,Pt-ac,Mv-ac,c-Pn-co and c-Mv-co-d were 30-40% higher,but the Cy was 14.89% lower;at the same time,the content of diglucosidated,methylated and acylated anthocyanin of grape skin under PG increased by 4.25%,6.25% and 12%,respectively,and the content and degree of acetylated anthocyanin increased by 22.79% and 32.68% respectively compared with VTS.(4)The bagging treatment affected the coloring of different trellis system/canopy type.The result showed that,the content of anthocyanin of pergola-bagging(PG-B)was significantly higer than vertical trellis system-bagging(VTS-B),meanwhile,its fruit color was better than VTS-B,this indicated that,the overshadow effect of horizontal canopy was better than bagging treatment.Micro-environment monitoring data also showed that,bagging treatment improved the humidity of fruit significantly,particularly in VTS-B treatment.The site conditions affected the coloring of different trellis system/canopy type as well.The result showed that,the Moldova's anthocyaninin content of PG and VTS in plain were reduced by 32.58% and 34.29%,respectively,compared with that in mountain areas.At the same time,the verification test of different trellis system / canopy type in mountainou areas showed that,the anthocyanin content of Moldova and Chambourcin of PG were higher than that of VTS,which increased by 32.59 and 5.54% respectively.(5)The total anthocyanin in fruit skin of Moldova was the highest,8131.08 mg/kg,followed by Cabernet Mitos,Acolon and Frontenac,7016.25-7546.66 mg/kg,and the contents in Manna and Cabernet Sauvignon were the lowest,2608.59 and 2442.87 mg/kg,respectively.The composition percentages of anthocyanin in Cabernet Sauvignon and Manna,Cabernet Mitos and Acolon,Kyoho Early and Moldova were similar,while were different in Becker and Frontenac.The modification degree of the anthocyanins in Becker,Moldova and Manna reached a high level of 94%-99%,while it was only 81.20% in Frontenac.Moldova,Cabernet Mitos and Acolon had more anthocyanin content and higher degree of modification,which showed the function of dyeing cultivars.(6)Vitis vinifera cultivars,such as Cabernet Sauvignon,Manna,Cabernet Mitos and Acolon didn't contain diglucosides,while Kyoho Early,Moldova,Frontenac and Becker contained much diglucosides,which didn't belong to Vitis vinifera.Malvidin and its derivatives(malvidins)were the main components in all grape varieties,peonidin and its derivatives(peonidins)were the second anthocyanins components in Vitis vinifera,while the petunidin and its derivatives(petunidins)were in Vitis vinifera×Vitis labrusca's.