Effect of Water Stress on Physiological Characteristic and Chemical Quality during Different Growth Stage of Flue-cured Tobacco

A Pot experiment was used to study the effect of water stress on physiology characteristic and chemistry quality during different growth period of flue-cured tobacco. The result indicated that, in the mature period of flue-cured tobacco, under the different water processing condition, protein, alkali, and total nitrogen in the middle leaf and the upper leaf increased. Total sugar, reducing sugar decreased, which was more severe with soil drought than with water excess, causing quality decrease of tobacco leaf. The sugar/nicotine, nitrogen/nicotine, and smoking value of flue-cured tobacco were reasonable with mild drought. During the different growth period of flue-cured tobacco, when the soil was drought or the water was excessive, MDA content, SOD activity, and PRO increased. Soil drought or the water excessive caused decline of the root system vigor and the photosynthesis. The optium soil moisture content for resettling stage, vigorous growing stage, budding stage, and mature stage was 65%, 80%, 80%, 65%, respectively.