Study On The Main Nutrient Situation Of Flue-cured Tobacco Growing Soil And The Relatively Fertilaization Application Techniques In Yunnnan Province

In this paper,soil pH,the content of organic matter,total nitrogen,potassium and phosphorus,available nitrogen,potassium and phosphorus,water-soluble chlorine of the main soil types was studied in the Yunnan Tobacco-growing areas.The paper provides the soil fertility for rich or deficiency evaluation,and the fertilizer application and techniques were also recommended.The results showed that:1,Organic matter and total nitrogen were rich in tobacco growing soils in yunnan, the average value was 33.0g.kg^-1 and 19.0g.kg^-1,respectively.The content of organic matter and total N inⅠandⅡclasses accounted for 54.3%and 63.8%,respectively. The mean of available nitrogen was 140.8mg.kg^-1 of all the samples and inⅠandⅡclasses accounted for 63.1%.Both organic matter and nitrogen varied greatly among different soil types.In general,paddy soils had the highest value followed by purple soil, while red soil and yellow soil had relatively low value.2,Total phosphorus content were rich in most of tobacco growing soil,but available phosphorus content were deficient in some new tobacco growing soil.The average available and total phosphorus content were 25.05mg/kg and 0.95 g/kg respectively. The available phosphorus content from high to low in tobacco growing areas in Yunnan ranged from Center to East to West to Southeast to Southwest and then Northeast;and the total phosphorus content from high to low ranged from Center to East to Southeast to West to Southwest to Northeast.For the major types of tobacco growing soil,the available phosphorus content,from high to low,ranged from red clay to paddy soil to purple soil to yellow soil,and the total phosphorus contents,from high to low,ranged from:red clay to paddy soil to yellow soil to purple soil.3,In average,the mean of available K content was 222.8mg.kg^-1 and total K content was 10.06 g.kg^-1.The available K content in tobacco growing regions in Yunnan,from high to low,ranged in East to Center to Northeast to West to Southeast to Southwest; and the total K content from high to low ranged in Northeast to Center to Southeast toWest to East to Southwest.For the major types of tobacco soils,the available K content,from high to low,ranged in red clay to yellow soil to purple soil to paddy soil and the total K,from high to low,ranged in:purple soil to paddy soil to red clay.4,The value of soil pH was range from 4.31 to 8.37,only 0.88%of samples was strong acid and the percentage between 4.5～5.5 was 27.67%,34.55%of samples is in an appropriate amount,15.81%of samples was greater 7.6.In general most soil pH is in an appropriate amount for the tobacco and varience was not greater.In general,the high soil organic matters and available nitrogen were found,and 25.48%of the soil organic matters is over 40g/kg and more than 78%the soil available nitrogen is over 100 mg/kg.Most soil pH is in an appropriate amount for the tobacco, only few(16.69%) has the low or high value.Soil available P has the same results,but the C.V is so greater,high or low value is found at some areas.For the soil available K, the result showed that soil available K is rich.For the soil nutrients of different areas,in general,nutrients of Puer area is less than other areas,and it means that fertilizer application is easy controlled.On the contrary the long history planting areas such as Kunming,Yuxi,Dali and Chuxiong have rich soil nutrients and fertilizer application should be pay more attention.New planting area such as Lijiang also has the high soil nutrients and balance fertilizer application is commended.