Soil microbiology focuses on the soil viruses, bacteria, actinomycetes, fungi, algae and protozoa, but it has traditionally also included investigations of the soil animals such as the nematodes, mites, and other microarthropods. These organisms, collectively referred to as the soil biota, function in a belowground ecosystem based on plant roots and litter as food sources. Modern soil microbiology represents an integration of microbiology with the concepts of soil science, chemistry, and ecology to understand the functions of microorganisms in the soil environment. The surface layers of soil contain the highest numbers and variety of microorganisms, because these layers receive the largest amounts of potential food sources from plants and animals. The soil biota form a belowground system based on the energy and nutrients that they receive from the decomposition of plant and animal tissues. The primary decomposers are the bacteria and fungi.

Table of Contents..

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1. The Soil
2. Soil Ecosystem and Soil Microbes
3. Taxonomy of Microorganisms
4. Microbial Biodiversity: the Natural Biological Capital of the Earth
5. Growth Patterns and Interactions of Mixed Populations
6. Chemical Interactions of Biological Origin in Soil
7. The Biofilm
8. Humus and Humic Substances
9. Soil Bacteria
10. Archaeobacteria, Actinomycetes and Actinoplanetes in Soil
11. Algae in Soil
12. Fungi in Soil
13. Nematode in Soil
14. Protozoa in Soil
15. The Rhizosphere
16. Carbon Cycle and Microbes
17. Sulphur Cycle and Microbes
18. Phosphorus Cycle
19. Iron Cycle
20. Soil Microbes and Nitrogen Fixation
21. Microbial Inoculants for Nitrogen Fixation
22. Rhizobium Biofertilizer
23. Application of Biofertilizers in Field Crops
24. Production of Rhizobium Biofertilizer
25. Azospirillum Biofertilizer
26. Azotobacter Biofertilizer
27. Blue Green Algae and Azolla as Biofertilizer
28. Estimation of Nitrogen Fixation
29. Biological Mobilization of Phosphorus
30. Vesicular-Arbuscular Mycorrhizae (VAM)
31. The Cyclic System of Nutrient Management
32. Laboratory Culture of Microbial Biofertilizers
33. Mass Production of Biofertilizers
34. Quality Control in Bioinoculants
35. Perspectives
36. Selected Bibliography
37. Subject Index