Studies On Soil Nutrients Distribution And The Relation Of Flue-cured Tobacco Chemical Index In Quing Of Yunan

On the basis of Qujing tobacco-growing areas in Yunnan province, the flue-cured tobacco chemical composition and soils nutrients were analyzed. The soils nutrients was spatial analyzed by method of geostatistics and by applying membership function and estimating weight values for each index by using the method of Principal component analysis, soil feasibility were comprehensively evaluated. The difference of soil elements contents in different altitude areas, the effect of soil nutrients on major tobacco chemical composition were also studied. Main results were as follows:1. The plant-tobacco soil is acidic in most areas of Qujing, alkaline in western of Huize and centre of Qilin. The content of organic matter (O.M.) is richer. The content of hydrolytic N is lower, suitable in Fuyuan and Shizong, lower in part of area in Huize, Luliang and Xuanwei. The content of quick-acting P is higher, increase from east to west obviously, the difference of area is larger. The content of quick-acting K is decline from southeast to northwest. The content of total N is suitable, decline from east to west, higher in part area of Fuyuan and Shizong, lower northern of Huize and western of Luliang. The content of total P is suitable in Xuanwei, Luping and Shizong, lower in other areas. The content of Total K is raise from east to west, suitable in western of Huize and junction of Malong and Zhangyi, lower in southern of Xuanwei and junction of Zhanyi and Fuyuan. The Integrated Nutrient Index (IFI) of Luoping, Malong, Shizong, Xuanwei were higher while Fuyuan and Huize were lowest. With the increase of altitude, the trend of soil fertility is reduced in Qujing.2. The content of soil available Ca in middle altitude area is highest, the low and lower areas are suitable, high and higher areas are lower. As the altitude increase, the content of soil available Mg decline. The contents of soil available Mg in low and lower areas is higher, the other area are suitable. The contents of soil available Ca and Mg are correlated with altitude negatively. The rate of Ca and Mg in middle altitude area is largest; the low and lower areas are smaller then other area significantly. The available Ca is correlated with available P negatively, correlated with other soil nutrients positive. The available Mg is correlated with alkali-hydro nitrogen and available P, correlated with other soil nutrients positive. The content of soil available Ca gradually decline from east to west in Qujing, available Mg is higher in south and north area and lower in middle area, the rate of Ca and Mg is larger in east area and smaller in south, north and west area.3. The contents of available B and Mn did not obviously change with altitude. With the rising altitude, the contents of soil available Zn, Fe and Cu increased, and soil available Mn declined firstly then rised. The contents of available Zn, Fe, Mn and Cu were rich among every altitude soil, soil available Mo was low and soil available B lack. Available Zn and Mn in tobacco soil of Qujing decreased from north to south but the character of spatial variation of available Fe was insignificant. Available Cu was declined from east to west and available Mo showed lower in the middle and higher in the south and north.4. The contents of total sugar and starch in Qujing are higher; the contents of reducing sugar, total nitrogen, total alkaloid and sulfur are suitable; the contents of potassium and chlorine are lower. The contents of sugar and starch in the variety of K326 are significantly lower than other varieties, the total nitrogen, total alkaloid, potassium and chlorine are significantly higher than other varieties. The content of sulfur in Hongda is highest. The difference of composition contents between Yunyan85 and Yunyan87 is no significant. The difference of composition's content except chlorine in each area is small. The correlation among composition content except potassium and chlorine is in extremely significant or significant level.5. The major index of tobacco chemical composition and soil nutrients were got by Partial Least-Squares (PLS), they are total sugar, reducing sugar, total nitrogen, total alkaloid, potassium, starch, calcium, magnesium, volatile alkali, chlorogenic acid, PH value, organic matter, total P, alkeline-N, olsen-P, olsen-K, available B and available Mo. Correlation analysis showed there was relationship between tobacco major chemical composition and soil nutrients.