Mechanism Of The Effects Of Light And Temperature On The Antioxidant Quality And Anthocyanins Metabolism Of Grape Berries

Bioactive substances and color are important indicators to measure the quality and maturity of grape berries.Phenolic substances such as anthocyanins are the main colorants and bioactive substances.Environmental factors such as temperature and light have important effects on anthocyanins accumulation.In this study,two regular grape cultivars(Red Globe,RG and Xin Yu,XY)both planted in Urumqi and Turpan were selected for investigation.The anthocyanins accumulation and other plant metabolites of berries at different developmental stages(S1,S2,S3,S4 and S5)in different environment were compared and the effects of environment on the development of grape berries quality were evaluated.And then exploring the mechanism of light and tempreature affecting anthocyanins metabolism and the formation of antioxidant quality in grape berries.The results of the study were as follows:(1)During grapes development,the average daily temperature and light intensity in Urumqi were lower when compared to Turpan.(2)The effects of light and tempreature on the accumulation of anthocyanins and other plant metabolites in grape berries at different developmental stages were studied.During grapes development,the phenolic content of berries showed a downward trend and the anthocyanins content showed an upward trend.The phenolic compounds such as anthocyanins in two grape varieties berries under different environments were same and peonidin-3-O-glucoside was the main anthocyanin.The content of phenolic compounds such as anthocyanins in grape berries planted in Urumqi was higher.(3)The effects of light and tempreature on the formation of grape berries quality at different developmental stages were studied.The grape berries planted in Urumqi had lower brightness value(L*),higher red-green value(a*),lower malondialdehyde contents and proline contents.Different from the early developmental stages,the sugar acid ratio of berries in Urumqi were higher the berries in Turpan at the late developmental stages.The chemical antioxidant activity,cell antioxidant activity and cell antiproliferative activity of Urumqi grape berries were stronger.(4)Clarify the differences in molecular mechanisms of anthocyanins and other phenolic substances metabolism in grape berries under different light and tempreature.PAL,4CL,DFR,F3 H,F3’5’H and ANS had higher transcription levels in Urumqi grape berries.There were 1096,397,570,839 and 699 differentially expressed genes in RG grape berries between two regions at five developmental stages,respectively.The differentially expressed genes were mainly enriched in pathways related to anthocyanins metabolisms such as the secondary metabolism metabolite pathway,phenylalanine metabolism pathway,flavonoid metabolism pathway,glutathione metabolism and photosynthesis pathway.In general,most of the genes related to anthocyanins synthesis and transport in Urumqi grape berries were up-regulated.The results showed that planting environment had a significant effect on anthocyanins metabolism and the formation of antioxidant quality of grape berries.Urumqi with lower temperature and light intensity were more conducive to the accumulation of anthocyanins and other plant metabolites and the formation of quality in grape berries.There were significant differences in the molecular mechanism of anthocyanins accumulation in grape berries under different light and tempreature.