The Nutrient Regimes In Soils Growing Tobacco And The Strategy In Fertilizing In Wenshan

Wenshan is one of the main tobacco producing areas in Yunnan, and the annual output of 2.5 x 104 tons. In this paper, the quality of soil nutrients and tobacco quality in tobacco growing areas was studied, and the effects of altitude and soil types on the quality of tobacco leaves were studied. The main conclusions are as follows:1 Chemical composition of tobacco leavesThe content of total sugar in Wenshan was appropriate, with a mean value of 25.15%, the total sugar content in tobacco was higher than 30%, the content of reducing sugar was 21.67%, and only some of total sugar content was higher than 24%. The content of total nitrogen in Wenshan was low, the mean was 1.65%, the total nitrogen content of tobacco leaves was lower than 1.8%, the nicotine content was 2.19%, and only some of nicotine in tobacco leaves was higher than 2.8%. Wenshan tobacco leaf potassium content is low with a mean value of 1.54%, most of the tobacco sample potassium content is lower than 2%; the chlorine content is low in tobacco leaves, the mean value is only 0.17%, only, a few tobacco samples chlorine content is higher than 0.3%. The ratio of sugar to nicotine in tobacco leaves was 12.29, and only a few sample was more than 12. The ratio of nitrogen to nicotine in tobacco leaves was 0.77, and only a few of the samples of tobacco leaf was more than 1. The tobacco leaf K/Cl is relatively high with a mean value of 24.46, and the chlorine content of tobacco leaf is relatively low. The difference of two sugar in tobacco leaves is small, the mean value is 4.44, which may be related to the maturity of tobacco leaf in Wenshan.2 Nutrient status of tobacco planting soilThe soil pH value was basically suitable for Wenshan, the average pH value was 6.34, only a small amount of soil pH was lower than 4.5 and higher than 7.5. The soil organic matter content in Wenshan was suitable, the mean value was 25.89 g/kg, and only a small amount of soil organic matter content was lower than lOg/kg and higher than 40g/kg. The soil total nitrogen content was 1.25 g/kg, only a small amount of soil total nitrogen content was lower than 0.8 g/kg and higher than 2 g/kg, soil available nitrogen content was higher, soil available nitrogen content was 130.65mg/kg, soil total phosphorus content was 22.2mg/kg, soil total phosphorus content was 0.87g/kg, soil total potassium content was lower than 40 g/kg, soil total potassium content was lower than 12 mg/kg. Wenshan tobacco growing soil exchange is very rich, the average value of 2788.05mg/kg, the soil exchangeable calcium content is more than 400mg/kg, the exchange of magnesium content is also very rich, the average 256.02mg/kg, only a small amount of soil exchangeable magnesium content is less than 25 mg/kg, the soil available sulfur content is very rich, the average content of 55.28mg/kg, a lot of soil available sulfur content is higher than 50 mg/kg. The soil available Fe content is very rich, the average content is mg/kg, the content of Soil Available Mn is 45.29mg/kg, the average content is 0.36mg/kg, the average content is 2.17mg/kg, and the average value is 2.03mg/kg, and the average value is 14.79mg/kg, and the average value is>30mg/kg, the average value is mg/kg, and only a small amount of 1 mg/kg is mg/kg.3Relationship between chemical composition of tobacco leaves and soil nutrientsThe soil pH value was significantly negatively correlated with total sugar and reducing sugar content in Wenshan, The content of total nitrogen in soil was significantly positive correlated with the content of chlorine in tobacco leaves, and the total potassium content in soil was positively correlated with the content of tobacco leaf, and the content of soil available potassium was significantly positively correlated with the content of potassium in tobacco leaves, and it was significantly positive correlated with leaf nitrogen. Soil exchangeable magnesium content was significantly positively correlated with the content of soil available Zn and Zn content in soil was significantly positively correlated with the content of soil available Fe and two sugar content. Soil available boron content was significantly positively correlated with total nitrogen content and nitrogen content.4 Improvement of chemical composition of tobacco leaves and suggestion on management of soil nutrients in tobacco planting soilAccording to the Wenshan tobacco chemical components of tobacco soil nutrients status quo status and put forward the following suggestions:according to the total nitrogen content of tobacco leaves less than 1.8% of the area, we should take effective measures to improve the utilization rate of nitrogen, such as water retaining agent and increased irrigation; for the chlorine content of tobacco is less than 0.3% of the area should be appropriate application of potassium chloride substitution of potassium sulfate; available for Maguan Xichou, Yanshan County, county of phosphorus content in<20 mg/kg area should be appropriate to increase the amount of phosphorus fertilizer, the available phosphorus content of>40 mg/kg in Malipo county should control the amount of phosphate, other regions should stabilize the current level of phosphorus; available in Xichou county and Yanshan County, K content was lower than 150 mg/kg area, should be appropriate to increase the K based on the existing amount of potassium fertilizer, the other areas remained stable, Quanzhou can improve K utilization appropriate measures, such as the application of slow-release potassium fertilizer; tobacco area in Quanzhou is very rich in elements, we should control the calcium and sulfur inputs. Statewide planting tobacco soil should be generally had the fertilizer; on the statewide planting tobacco soil available zinc content is lower than 1.5 mg/kg of Guangnan and Qiubei County should be increased zinc application elements.