Agricultural Sustainability

Soil Classification: Synthetic Soils

These soils con­ tain significant populations of microorganisms which are able to fix atmos­pheric nitrogen and carbon dioxide into complex molecules such as amino acids, proteins and carbohydrates. Such micro­ organisms include photosynthetic bacteria which perform incomplete photosynthesis anaerobically, ce1tain Phycomycetes (fungi that resemble algae), and both green algae and blue-green algae which function aero­bically. […]

Photosynthetic Bacteria: Benefi­cial Soil Microorganisms

The photosynthetic bacteria, which perform incomplete photosynthesis an­ aerobically, are highly desirable, benefi­cial soil microorganisms because they are able to detoxify soils by transforming re­duced, putrefactive substances such as hydrogen sulfide into useful substrates. This helps to ensure efficient utilization of organic matter and to improve soil fer­tility. Photosynthesis involves the photo­ catalyzed splitting of […]

Relationships Between Putrefaction, Fermentation and Synthesis

The processes of putrefaction, fermentation, and synthesis proceed simul­taneously according to the appropriate types and numbers of microorganisms that are present in the soil. The impact on soil quality attributes and related soil properties is determined by the dominant process. The production of organic sub­ stances by microorganisms results from the intake of positive ions, […]

Soil Health: Nitrogen-fixing microorganisms

The term “synthesis” as used here refers to the biosynthetic capacity of certain microorganisms to derive metabolic energy by “fixing” atmospheric nitrogen and/or carbon dioxide. In this context we refer to these as “synthetic” microorganisms , and if they should become a pre­ dominant part of the soil microflora, then the soil would be termed […]

Functions of Microorganisms: Putrefaction, Fermentation and Synthesis

Soil microorganisms can be classified into decomposer and synthetic microor­ganisms. The decomposer microorganisms are subdivided into groups that perform oxidative and fermentative decomposition. The fermentative group is further divided into useful fermentation (simply called fermentation) and harmful fermentation (called putrefaction). The synthetic micro­ organisms can be subdivided into groups having the physiological abilities to fix […]

Application of Beneficial Microorganisms to Soil

The application of beneficial microorganisms to soil can help to define the structure and establishment of natural ecosystems. The greater the diversity of the cultivated plants that are grown and the more chemically complex the biomass, the greater the diversity of the soil microflora as to their types, numbers and activities. The application of a […]

Classification of soils based on their microbiological properties

Most soils are classified on the basis of their chemical and physical properties; little has been done to classify soils ac­ cording to their microbiological proper­ ties. The reason for this is that a soil’s chemical and physical properties are more readily defined and measured than their microbiological properties. Improved soil quality is usually characterized […]

Application of Beneficial and Effective Microorganisms

A New Dimension for a Sustainable Agriculture and Environ­ment Many microbiologists believe that the total number of soil microorganisms can be increased by applying organic amendments to the soil. This is generally true because most soil microorganisms are heterotrophic, i.e., they require complex organic molecules of carbon and nitrogen for metabolism and biosynthesis.Whether the regular […]

Nutrient-Deficiencies and Applying Pesti­cides

Chemical-based conventional fann­ing methods are not unlike symptomatic therapy. Examples of this are applying fertilizers when crops shows symptoms of nutrient-deficiencies, and applying pesti­cides whenever crops are attacked by in­sects and diseases. In efforts to control the soil microflora some scientists feel that the introduction of beneficial micro­ organisms should follow a symptomatic approach. However, […]

Microorganisms and Plant Pathogens

It is noteworthy that most of the microorganisms encountered in any par­ticular soil are harmless to plants with only a relatively few that function as plant pathogens or potential pathogens. Harmful microorganisms become dominant if conditions develop that are favor­able to their growth, activity and reproduction.   Under such conditions,   soil­ borne pathogens (e.g., fungal pathogens) […]