Abstract: Effects of high Ca and full nutritional complex solutions on fruit quality and puffing rate of fruit were studied in developing Satsuma mandarin (Citrus unshiu cv. Miyagawa Wase)fruit. Before fruit coloring, the ratios of peel to the whole fruit decreased while the ratios of juice sacs to the whole fruit increased with fruit development. During fruit coloring, the ratios of peel to the whole fruit increased slightly, while ratios of juice sacs to the whole fruit had a little decrease. At the stage of full mature harvest, the ratios of peel to the whole fresh fruit reached the lowest value, and the ratios of juice sacs to the whole fresh fruit had the highest value. The ratio of peel to whole fruit in the two complex nutrient solutions treatment fruit was lowered than that in control fruit. In contrary, the ratio of juice sacs to the whole fruit was higher in complex nutrient solutions than that in control fruit. The contents of total soluble solids, glucose, fructose and sucrose also increased in juice sacs of complex nutrient solution treatment, but the treatment of complex nutrient solutions had little effects on titratable acid content. In comparison to the control, the rate of puffing fruit in the treatment of complex nutrient solutions significantly decreased and the puffing index in full nutrient and high\|Ca type solution decreased by 13 and 18 percentage points, respectively. These results showed the application of complex nutrients improved the quality of full mature Satsusma mandarin fruits and inhibited the occurrence of puffing fruit, and added more Ca in the solution resulted in lower puffing fruit rate．

Key words: Satsuma mandarin, full\|mature cultivation, complex nutrients, fruit quality, peel puffing