Abstract:Yuquandongzao was used as material, four treatments, A (1.0 kg bio–bacterial agents(BBA) and 0.5kg S–based compound fertilizer per tree), B(1.0 kg bio–bacterial manure(BBM) and 0.5 kg S–based compound fertilizer per tree), C( 0.5 kg BBA, 0.5 kg BBM and 0.5 kg S–based compound fertilizer per tree) and D(1.0 kg rot chicken manure (RCM) and 0.5 kg S–based compound fertilizer per tree), were designed to study the effects of fertilizations on phytosynthetic characteristics and fruit quality of Yuquandongzao. The results showed that the treatment B had the highest average Pn while the treatment C had the lowest average Pn in growing seasons. The treatment B had the biggest single fruit weight of 17.09 g per fruit and the highest yield of 14 025 kg per hectare. The fruits of treatment B had the highest content (10.34%) of reducing sugar and soluble solids (22.8%). The fruits of treatment B had the highest ratio (41.25/89.58) of sugar (soluble solids) to acid. The fruits of treatment D had the highest content (4.33 mg/g) of vitamin C. The fruits of treatment C had the highest content titratable acid of 0.28%. The principal component analysis to integrated model of fruit quality showed that the fruits of treatment B had the highest score of 1.824 6 and the best quality, while the fruits of treatment C had the lowest score of –0.329 9 and the worst quality. The sequence of the yield and quality of the treatments were consistent with the sequence of the quarterly average of the net photosynthetic rate in the growing season. According to the comprehensive results, the effect of B treatment on improving the photosynthesis and fruit yield and quality of Yuquandongzao was the best.