Soil microflora
qualitative composite on of soil microbes. Most of the soil bacteria, blue-green algae, diatoms
and protozoa prefer a neutral or slightly alkaline reaction between PH 4.5 and 8.0 and fungi
grow in acidic reaction between PH 4.5 and 6.5 while actinomycetes prefer slightly alkaline
soil reactions. Soil reactions also influence the type of the bacteria present in soil. For
example nitrifying bacteria (Nitrosomonas & Nitrobacter) and diazotrophs like Azotobacter
are absent totally or inactive in acid soils, while diazotrophs like Beijerinckia, Derxia, and
sulphur oxidizing bacteria like Thiobacillus thiooxidans are active in acidic soils.
8. Soil Organic Matter: The organic matter in soil being the chief source of energy and food
for most of the soil organisms, it has great influence on the microbial population. Organic
matter influence directly or indirectly on the population and activity of soil microorganisms. It
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