Sdudy On Flue-cured Tobacco Grown In The Volcanic Soil Of Anti-waterlogging

In this research,through the detection and analysis the specific gravity,bulk density and porosity and nutrient status of volcanic ash soil in Tengchong,Cleared the basic features of volcanic ash soil;Through pot experiment,studied on under waterlogging stress,the variation of the root growth and physiological characteristics of flue-cured tobacco which grown in paddy soils and in volcanic ash soil,and identified the cultivation advantage of volcanic ash soil.By incorporating different particle sizes and different proportions of the volcano ash gravel into tobacco planting soil,studied the the influences of growth and internal quality of the flue-cured tobacco caused by incorporating volcanic ash gravel,to provide theoretical and practical basis for the improvement of tobacco planting soil.The main results of this study are as follows:1、Through the analysis of90samples of volcano ash soil in Tengchong showed that,the bulk density of volcano ash soil in Tengchong is very small,and the average value is0.84g/cm3.The average value of porosity is68.6%.The pH value is appropriate, average value is5.94.The content of organic matter is high,and average value is49.30g/kg.The content of nitrogen is above the average.The content of available phosphorus is low,and average value is18.5mg/kg.The content of available potassium is rich,and average value is278mg/kg.The content of effective zinc is rich,and there are90%of the sample is above the critical value of1.5mg/kg.While The content of effective boron is very poor,there are80%of the sample is lower than the critical value of0.5mg/kg.The content of water soluble chloride is low,there are60%of the sample is lower than the critical value of30mg/kg.2^Under waterlogging stress conditions,each processing tobacco root growth conditions and physiological characteristics have been adversely affected.On the root growth condition,the biggest adversely impact showed in A3,which is the severer waterlogging stress treatment in tobacco planting paddy soil,followed by the mildly waterlogging stress treatment A2,in tobacco planting paddy soil,this two treatment is lower than control treatment Al all in root volume,root fresh weight,root dry weight and root activity after21d,And has been sustained reduction.in tobacco planting volcano ash soil, the above indexes of the mildly waterlogging stress treatment B2and the severer waterlogging stress treatment B3are also lower than control treatment B1in21d, but in28d, the root volume,root fresh weight,root dry weight and root activity of the severer waterlogging stress treatment B3,have different degrees of increase compared with21d.In the physiological characteristics,the content of MDA,Pro,and the activity of POD are showing a rising trend,while the activity of SOD has a trend of increase first and then decrease,which showed that under waterlogging stress conditions,tobacco have been adversely affected,with the flooding duration and flooding degree deepening these adverse effects gradually.But throughout the test period,the tobacco which planted in volcano ash soil is better than he tobacco which planted in paddy field soil in all above indexes/which shows that the adversely affected caused by waterlogging stress is lower in volcanic ash soil, Therefore,Under waterlogging stress conditions,the volcanic ash soil is more suitable for tobacco growth.3、Through the research, the influence of growth and physicochemical characteristics in Tengchong caused by incorporating volcano ash gravel in tobacco planting soil showed that,incorporating volcanic ash gravel into tobacco planting soil can increase the length and width of the tobacco leaf,and can increase the content of potassium and starch,reduce the content of nicotine,increase the content of sugar and reduce disaccharide,and increase sugar-nicotine ratio and nitrogen-nicotine ratio.The best incorporation of volcano ash gravel size is5mm,the optimum ratio is20%,and the incorporation of volcano ash gravel in paddy field soil has better effect than incorporation in upland soil.