Effects Of Density And Different Nitrogen Rate On Growth, Yield And Quality Of Flue-cured Tobacco From Shaoyang

This paper used the flue-cured tobacco varieties K326 as experimental material, systematically studied effects of density and nitrogen rate on the growth, yield and quality of flue-cured tobacco in Shaoyang. The major findings are as follows:1. Density has a certain effect on the agronomic traits, but the trend is not obvious. With the increase of the nitrogen rate, the plant height, stem circumference, the largest leaf area and the pitch increased. Density and nitrogen interaction significant effect tobacco agronomic traits.2. The main factors influencing tobacco leaf area index was nitrogen, followed by density, the last was density and nitrogen combination. With the increase of the nitrogen rate, leaf area index increased.3. In vigorous growth period and topping period, with the increase of planting density, leaf chlorophyll content and net photosynthetic rate first increased and then decreased. With the increase of the nitrogen rate, the content of chlorophyll and net photosynthetic rate, transpiration rate, intercellular CO2 concentration increased. In the mature period, leaf chlorophyll content and net photosynthetic rate reduced along with the increase of density. Density and nitrogen significantly effect photosynthesis. Compared with the different treatments, treatment A2B3 which was planting density 18182/hm and nitrogen 135Kg/hm2 has best photosynthesis performance.4. The main factors influencing tobacco physical properties and chemical composition was nitrogen, followed by density and nitrogen combination, the last was density. With the increase of planting density, leaf length, leaf width, leaf thickness, leaf weight and weight per unit area decreased.With the increase of nitrogen rate, leaf length, leaf width, leaf thickness, leaf weight, equilibrium moisture content and weight per unit area increased.With the increase of planting density, total sugar, reducing sugar, total nitrogen and potassium content increased, nicotine and starch decreased. With the increase of nitrogen rate, total sugar, reducing sugar, starch content decreased, nicotine, chlorine, potassium, total nitrogen content increased.5. The main factors influencing tobacco economic characteristics was density and nitrogen combination, followed by nitrogen, the last was density. Compared with the different treatments, treatment A2B3 which was planting density 18182/hm2 and nitrogen 135Kg/hm2 has best economic characteristics performance. The yield and output value respectively were 2380 kg/hm2 and 49668.18yuan/hm2. It can be applied in production.