Soil Enzyme Activities in Andosol Paddy Fields (1) Relationship between Soil Enzyme (β-Acetylglucosaminidase, Protease, and Adenosine Deaminase) Activities and Microbial Counts

Abstract

To abtain information about the relationship between soil enzyne activities and soil microbial counts in Andsol paddy fields, we measured the activities of β-acetylglucosaminidase (EC. 3. 2. 1. 30), protease (EC. 3. 4. 21. 14), and adenosine deaminase (EC. 3. 5. 4. 4.), and counts of fungi, actinomycetes, and bacteria in the soils curing the growth of rice plant. The results obtained were as follows : (1) Three kinds of enzyme activities were higher in soils with application of organic matter which consisted of manure added with rice straw every year than in soils with non-application. (2) An application of a different amount of nitrogenous fertilizers influenced soil microorganisms. Application of 0.8kg N/a to soil effected a greater increase in soil microorganisms. (3) The counts of actinomydetes were correlated with adenosine deaminase activities and with β-acetylglucosaminidase activities at a 5% level.