Effect Of Nutrient Solution On Fruit Development And Quality Of Full Ripe And Delayed Cultivation 'Miyagawa' Satsuma Mandarin Fruit

In these experiments, Satsuma mandarin(Citrus unshiu cv'Miyagawa Wase') full ripe fruit treated with total nutrient solution and Ca nutrient solution, greenhouse Satsuma mandarin delayed cultivation fruit treated with Ca nutrient solution were used as materials. Quality indicators such as ratio of various parts of fruit to the whole fruit, color parameters of peel, peel thickness, puffing rate of fruit, total soluble solids, sugars and titratable acid content were determined. Fruit developmental physiology, effects of total nutrient solution and Ca nutrient solution to fruit quality were studied. Finally, effects of Ca nutrient solution on the antioxidant capacity of delayed harvest Satsuma mandarin fruit were analysed. The main results were as follows:In the development of full ripe Satsuma mandarin fruit, with fruit grow bigger, the ratio of juice sacs to the whole fruit keep rising, while peel grow thinner and the ratio of peel to the whole fruit falling. Red saturation a* and yellow saturation b* rapid sacend after September 28, at the same time, brightness of fruit L* gradually ascend. The most hightest titratable acid content was on August 6, and then descend later. Total soluble solids can reach 13% when full ripe picking, and fruit sugar also accumulated. The use of total nutrient solution and Ca nutrient solution significantly increased the total sugar content but had little effects on titratable acid content. Total nutrient solution elevated the rate of unfloat skin in 9 percentage point in comparison to control fruit, the puffing index decreased by 13 percentage point, Ca nutrient solution elevated the rate of unfloat skin in 17 percentage point in comparison to control fruit, the puffing index decreased by 18 percentage point. Ca nutrient solution had better effects in improving fruit sugar and inhibiting the occurrence of puffing fruit. The ratios of peel to the whole fruit were increased during the later periods of delayed cultivation, while the ratios of juice sacs to the whole fruit were decreased. Ca nutrient solution treatment lowered the ratio of peel to whole fruit than that in control fruit in delayed cultivation. In contrary, the ratio of juice sacs to the whole fruit was higher in Ca nutrient solution treated fruit than that in control fruit. Sugar accumulation were different in different tissues, edible tissue (juice sacs, segment epidermis) major accumulated sucrose while peel major accumulated hexose. The contents of total soluble solids, glucose, fructose and sucrose were increased in Ca nutrient solution treated fruit, while the treatment of Ca nutrient solution had little effects on titratable acid content. In comparison to control fruit, treatment of Ca nutrient solution significantly decreased the rate of puffing fruit, the puffing index decreased by 13 percentage point. These results showed the application of Ca nutrient solution improved the quality of delayed cultivation Satsuma mandarin fruit and inhibited the occurrence of puffing fruit.During the course of greenhouse'Miyagawa'Satsuma mandarin fruit development and delayed cultivation, the contents of carotenoids first raise and then gradually decline after January 4. In contrary, the contents of flavonoids first rapidly drop and then slightly rise after October 20. The antioxidant activity of fruit had a certain positive correlation with total flavonoids content. Antioxidant activity is the results of total flavonoids, carotenoids and other antioxidant.