| In this experiment,sweet persimmon cultivar ’Taishuu’ and astringent persimmon cultivar’Nantongxiaofangshi’ were used as test materials,and the characteristics of the components and the content changes of sugar,acid and tannin in persimmon fruit were analyzed.The effects of exogenous gibberellin,hand pollination and fruit bagging treatments on the components and content changes of sugar,acid and tannin in ’Taishuu’ fruits were studied.The main results were as follows:1.The sugar components of Nantongxiaofangshi’ and ’Taishuu’ fruit were consisted of maltohexaose,raffinose,sucrose,glucose,fructose and mannitol;’Nantongxiaofangshi’ and’Taishuu’ were all glucose accumulated fruits.There were six kinds of organic acids such as oxalic acid,tartaric acid,quinic acid,malic acid,citric acid and succinic acid in the’Nantongxiaofangshi’ and Taishuu’ fruit.’Nantongxiaofangshi’ belonged to citric acid-dominant type,while Taishuu’ belonged to malic acid-dominant type.The soluble tannin of’Nantongxiaofangshi’ and ’Taishuu’ fruit was composed of three phenolic compounds,such as gallic acid,gallacatechin and catechin.’Nantongxiaofangshi’ belonged to gallocatechin-dominant type,and ’Taishuu’ belonged to gallic acid-dominant type.The content of soluble tannin in’Nantongxiaofangshi’ was significantly higher than that of Taishuu’,and the gallacatechin was the key phenolic compound of fruit astringency.2.The appropriate storage temperature of persimmon pollen was 40C,and the content changes in the of sugar,acid and tannin components had close relationships with the sources of pollen,’Gaoyou 2’ could be used as one of superior pollinating strain or cultivar of Taishuu’ in YangZhou.3.After the treatments of exogenous GA3 and GA4+7,the accumulation of total soluble sugar in the fruit was significantly promoted,the biosynthesis of sucrose and raffinose was inhibited,and the the accumulation of glucose,fructose and mannito was affected.The GA3 and GA4+7 treatments increased the content of malic acid and quinic acid but reduced the contents of lemon acid,oxalic acid and succinic acid in fruits.The treatments of GA3 could make soluble tannin content rise significantly,however,the treatments of GA4+7 could not only significantly cut down the soluble tannin content in fruits,but also evidently increase the fruit weight.Comparing the influences of two kinds of GA treatments on the fruit growth and quality formation,1.0%GA4+7 calyx treatment and 1.5%GA4+7 fruit stalk treatment were recommended for production.4.There was no significant effect on the fruit weight growth of ’Taishuu’ in bagging treatments.However,the contents of fruit total soluble sugar,glucose and fructose significantly increased,and the contents of total organic acid and tannin decreased in the fruits which were done with red fruit bags. |
