Study On Content Of Soil Nutrient,Functional Microorganism And Soil Enzyme In Four Types Of Soil

42 ABSTRACT In this paper,take the four soil types as the research object: red soil,purple soil,sandy soil and paddy soil,to analyze the differences in nutrient of the four soil types,the quantity change of fungus(bacteria,fungi and actinomycetes)before transplanting,the quantity change of functional bacteria in and non rhizosphere after transplanting,the soil enzymes,the chemical properties of flue-cured tobacco leaves and the neutral aroma components of tobacco leaves in middle leaves.Draw the following conclusions:The p H values of the four types soil were all suitable for the growth of tobacco plants,and the red soil was acidic.The overall fertility of the four types soil behave like this: red soil >purple soil> paddy soil > sandy soil.The available phosphorus content in red soil was on the low side,the alkali hydrolyzable nitrogen in purple soil was significantly lower than that of others,the content of other components was almost the same;In addition to the content of available phosphorus in sandy soil,the contents of other components were lower.The content of each component in paddy soil was in the middle level.The total amount of soil microorganism was affected by p H value and soil comprehensive fertility,the total amount of microorganism behave like this: purple soil >red soil >paddy soil>white sand,dominated by bacteria and the number accounted 84.6%-99.5% of the total.The total amount of three kinds of bacteria in paddy soil was bacteria > fungi > actinomycetes,and the proportion of bacteria in the soil was decreased;The other three types soil microbes behave like this:bacteria > actinomycetes > fungi.There is a close relationship between soil nutrient,soil microbial quantity and soil enzyme activity,soil enzyme activity was affected by both soil nutrient and soil microbial quantity.Urease activity was highest in red loam,sucrase activity was highest in purple soil,catalase was highest in paddy soil.The changing trend of functional bacteria in rhizosphere and non rhizosphere was different at different growth stages.The trends of azotobacter in rhizosphere and non rhizosphere were different,the trends of ammonification bacteria was almost the same,the trends of potassium bacteria was basically opposite,the trends of phosphate solubilizing bacteria had large difference.The total quantity of the four functional bacteria behave like this: in rhizosphere > non rhizosphere,and rhizosphere effect > 1,the number of rhizosphere azotobacter had no significant difference,the number of ammonification bacteria was highest in sandy soil,rhizosphere potassiumbacteria in purple soil had the maximum number,the numbers of rhizosphere phosphate-solubilizing bacteria was in different periods;The number of non rhizosphere azotobacter was higher in red soil and purple soil,the level of non rhizosphere ammonification bacteria and non rhizosphere potassium bacteria bacteria in different periods had little difference,Non rhizosphere phosphate-solubilizing bacteria in purple soil had a larger number.The main chemical components of tobacco leaves in different types soil behave like this: In addition to the total sugar had some differences,other chemical components of tobacco leaves were not significantly different.The contents of chlorine,nicotine and total nitrogen in flue-cured tobacco leaves were basically the same change,and the content of the three was higher in red soil;The content of total sugar and potassium was higher in sandy soil,and the content of reducing sugar was higher in paddy soil.From the total performance of each soil type,the chemical composition of tobacco leaf was better.32 kinds of neutral aroma components were detected in the four soils,the total content of neutral aroma components behave like this: T4 treatment > T3 treatment > T2 treatment > T1 treatment.The main neutral aroma were as follows: neoplytadiene,furaldehyde,?-damascenone,giant bean three ketene,phenylacetaldehyde,guaiacol and Luo Yan bluegrass ketone;In addition to the neophytadiene,the proportion of the other six aroma components in all neutral aroma components was: The proportion of red soil was 6.5%,the proportion of purple loam was 4.8%,the proportion of sandy soil was about 7.1%,and the proportion of paddy soil was about 6.6%.