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The effect of one-time application of controlled-release integrated fertilizer on photosynthetic traits and yield was investigated, to provide technical support for the application of controlled-release integrated fertilizer in tobacco production. The tobacco cultivar ‘Yunyan 87’ was selected as the experimental materials in a field experiment in Liangshan tobacco-growing area of Sichuan Province. Three fertilizer treatments were set up:local conventional fertilizer (T1 ), 750 kg / hm² controlled-release integrated fertilizer (T2) and 900 kg / hm² controlled-release integrated fertilizer ( T3). The stand type characteristics, leaf chlorophyll content, areas of green leaves, hotosynthetic rate at flat top stage, and the yield were investigated. Compared with conventional fertilization, one-time application of controlled-release integrated fertilizer enhanced the average stem circumference, SPAD value of upper leaves, areas of green leaves and net photosynthetic rate of ‘Yunyan 87’. The application of controlled-release integrated fertilizer (T2 and T3 ) increased the yield by 8.19% and 13. 80%, respectively, and significantly increased the yield of Zhongju 3 and Zhongju 2, the output value increased by 6 058. 95 and 12 874. 65 yuan / hm², respectively. Increasing the amount of fertilizer could significantly enhance the SPAD value and net photosynthetic rate of the upper leaves of ‘Yunyan 87’, which followed by higher yield and output value. The variation of yield and output value between different fertilizer treatments might be caused by difference of photosynthetic functions of upper leaves. In conclusion, compared with the traditional multiple fertilization, the application of controlled-release integrated fertilizer is beneficial to promote the development of upper leaf, improve tobacco yield, optimize grade structure and increase output value. Appropriately increasing the application amount of controlled-release integrated fertilizer could improve the yield and output value of tobacco. For ‘Yunyan 87’, the effect of increasing yield was more obvious when the application amount of controlled-release integrated fertilizer was 900 kg / hm². [ABSTRACT FROM AUTHOR]

[Objective]The study aims to investigate the feasibility of using color parameters to estimate the curing characteristics of fresh flue-cured tobacco leaves in maturity process. [Method] The color parameters of flue-cured tobacco leaves with different maturity were measured by color difference meter and curing characteristics were studied through the black box testing using flue-cured tobacco NCI 02 middle leaves. Cured-leaves were taken to verify the curing characteristics of different maturity fresh flue-cured tobacco leaves. [Result] The result shows that color values of front and back of flue-cured tobacco leaves had similar changing trend with the enhancement of leaves maturity. The relationship between color parameters(L ,b ,C) and maturity of tobacco leaves was statistically significant, which could be used to distinguish maturity. [Conclusion]The curing characteristics of flue-cured tobacco leaves with different maturity were different. The Fisher discriminant function based on color parameters can be used to identify different maturity leaves. Color parameters could be used as an auxiliary index to judge the curing characteristics of fresh flue-cured tobacco leaves. [ABSTRACT FROM AUTHOR]