It is important to understand that biostimulants do not act singly but rather act in conjunction with, or in opposition to, each other such that growth and development represents the net effect of biostimulant balance. Generally the hormonal biostimulants are thought to include five main classes: auxins, gibberellins, cytokinins, abscisic acid and ethylene. There are […]
Enzymes and hormones are proteins. While all living cells produce enzymes and hormones, enzymes themselves are not alive. They function by altering other plant molecules by combining to form a complex molecular structure in which chemical reactions talce place. The enzyme and the hormone are true catalysts and separate from the product of the reaction. […]
From the time humans made the transition from hunter-gatherer societies to settled communities with a local agricultural base, the need has existed to improve the quantity and quality of our fruits, vegetables and grasses. Initial steps in this age-old undertaking included better selection of varieties for controlled propagation and improving agronomic practices related to tilling, […]
The microflora of disease-suppressive soils is usually dominated by antagonistic microorganisms that produce copious amounts of antibiotics. These include fungi of the genera Penicillium, Tricho derma, and Aspergillus, and actinomycetes of the genus Streptomyces. The antibiotics they produce can have biostatic and biocidal effects on soil-borne plant pathogens, including Fusarium which would have an incidence […]
In disease-inducing soils, plant pathogenic microorganisms such as Fusarium fungi can comprise 5 to 20 percent of the total microflora. If fresh organic matter with a high nitrogen content is applied to such a soil, incompletely oxidized products can arise that are malodorous and toxic to growing plants. Such soils tend to cause frequent infestations […]
Soils can be characterized according to their in indigenous microflora which perform putrefactive, fermentative, synthetic and zymogenic reactions and processes. In most soils, these functions are going on simultaneously with the rate and extent of each determined by the types and numbers of associated microorganisms that are ac tively involved at any one time. Pro-Soil […]
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 […]
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 […]
An example of the importance of controlling the soil microflora and how certain cultural and management practices can facilitate such control is useful here. Vegetable cultivars are often selected on their ability to grow and produce over a wide range of temperatures. Under cool, temperate conditions there are generally few pest and disease problems. However, […]
The use of mixed cultures has been criticized be cause it is difficult to demonstrate conclusively which microorganisms are responsible for the observed effects, how the introduced microorganisms interact with the indigenous species, and how these new associations affect the soil plant environment. Thus, the use of mixed cultures of beneficial micro-organ isms as soil […]
