The Influence Of Different Maturity On The Quality Of Upper Leaf Of Flue-cured Tobacco

By the way of randomized block design, combined with analysis the appearance quality, chemical composition and aroma and taste, researching the relationship between maturity and quality of flue-cured tobacco, in order to seek the best maturing period ,and offering the reference basis for improving quality and usability of upper tobacco leaf.The results showed that:(l)with the maturing degree's rising ,the first-class leaf rate, better-than-average leaf rate and average price present the trend of falling after rising. The 4^th Treatment was best, and the 3^rd was better and others were worse. Those indicated that the way improving the maturing can improving the rate of first-class and better-than-average leaf and the average price. But the result of 5^th Treatment showed that when the leaf was excessively ripe, it can make the rate of first-class and better-than-average leaf and the average price decrease. (2) The content of nicotine, total Nitrogen and protein showed the trend of lowering first and then rising, the content of total sugar and reducing sugar showed the opposite trend; the chemical compositions of 3rd Treatment and 4^th Treatment were more coordinate. (3) The score of aroma and taste of 4^th Treatment was highest, which of 3^rd Treatment was higher, and others were lower. Those showed that the internal quality of 4^th Treatment was best and which of 3^rd Treatment was better, and other were worse.According to the result of first-class and better-than-average leaf and the average price, the chemical composition and coordinate and the score of aroma and taste, from the angle of coordinating the composition and improving the yield and aroma and taste, considering the best maturing period should appear the characteristic of 4^th Treatment, and the better period should be 3^rd Treatment. No matter earlier or later, it will have disadvantage to the quality of leaf of flue-cured tobacco.