Beneficial organisms

Tables 2.6 and 2.7 give examples of the modes of action of pollutants in animals and in plants/fungi, respectively. It is noteworthy that many of the chemicals represented are pesticides. Pesticides are designed to be toxic to target species. On the other hand, manufacturers seek to minimize toxicity to humans, beneficial organisms and, more generally, nontarget species. Selective toxicity is an important issue. Regardful of the potential risks associated with the release of bioactive compounds into the environment, regulatory authorities usually require evidence of the mode of toxic action before pesticides can be marketed. Other industrial chemicals are not subject to such strict regulatory requirements, and their mode of action is frequently unknown.

Pfiffner, L. Luka, H. (2000) Enhancing Beneficial Organisms with Field Margins - an Important Strategy for Indirect Pest Control on Organic Farms. Proceedings of the 13th International IFOAM Scientific Conference, Basel, Switzerland, p. 105. 

Haskell, P.T. and McEwen, P., Eds., Ecotoxicology Pesticides and Beneficial Organisms, Chapman Hall, New York, 1998. 

The aim of this chapter is to summarize the information available about the extracellular proteases of entomopathogenic fungi, focusing on Metarhizium and Beauveria species. A large number of protease enzymes have been purified, cloned and characterized from these beneficial organisms. These results will be reviewed and data about the regulation of proteases as well as their role during the biocontrol process will be discussed. 

In order to achieve this, the main emphasis is on building a living soil and environment that encourages beneficial organisms at all levels. When the land is enriched, the soil creates strong, healthy crops. These plants have more inherent resistance to diseases and pests and therefore need less intervention - chemical or otherwise. This focus in the... 

When tests are performed on terrestrial animals, it is common to apply single (measured) doses orally, topically (i.e., applied to the skin or cuticle), or by injection into tissues or body fluids. There can be very large differences among groups of organisms and among species in their susceptibility to the toxic action of chemicals. The selective toxicity ratio (SER) is expressed in terms of the median lethal dose, and is important for the differentiation between beneficial organisms and pests ... 

Predators and Parasites—Organisms known to attack insert (and insect-like) pests in their native environment can be imported or reared in labomto-ries and released in infested areas. This is done only after the parasites or predators are determined to be harmless to man, animals, plants, and other beneficial organisms. For example, several kinds of parasites and predators of the alfalfa weevil have been imported from Europe and Asia and released in the infested areas in this country. Several species have become established and are helping to reduce pest numbers. However, they do not always prevent serious outbreaks and the resultant damage. 

Most control strategies take advantage of the natural controls provided by the pest s natural enemies. When choosing a pesticide, consider what effect it will have on these beneficial organisms. Ask your pesticide dealer, agricultural extension agent, or other experts for advice. 

Prevention and Control The relationship of legumes and these bacteria (Rhizobium spp.) is generally beneficial to both. Plants supply bacteria with nutrients bacteria convert nitrogen from the air into a form that plants can use. To promote growth of these beneficial organisms, buy the bacteria in powder form (called inoculant) and dust the seeds of appropriate crops before planting. Certain species work better with particular plants, so buy the right inoculant for your crop. 

The natural enemies of garden pests are often overlooked when gardeners consider their pest-control options. In fact, more beneficial organisms visit your plants than do pests. 

Beneficial organisms go unnoticed because they re inconspicuous in size and habit. They re so efficient, you may never have realized that pests were there. Even so, pest outbreaks are clouds with silver linings since they attract more beneficials to your garden. It s a good idea to encourage natural enemies whenever you can. There are several ways to attract them to your garden, and keep them there. 

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