BENEFICIAL

In and , a beneficial is any organism that benefits the growing process, including , arachnids, some , , , fungi, , and . Benefits include control, , and maintenance of soil health. The opposite of beneficial organisms are pests, which are organisms believed to be harmful to the growing process.

Beneficial or pest The distinction between beneficial and pest is arbitrary, subjectively determined by examining the effect of a particular organism in a specific growing situation.

Insects Beneficial insects can include predators (such as ladybugs) of pest insects, and pollinators (such as , which are an integral part of the growth cycle of many crops). Increasingly certain species of insects are managed and used to intervene where natural pollination or biological control is insufficient, usually due to human disturbance of the balance of nature.

Nematodes Certain microscopic nematodes (worms) are beneficial in destroying and controlling populations of larvae that are damaging or deadly to crops and other plants. They are commonly used in organic gardening for their ability to kill various kinds of harmful larvae.

Microorganisms Many different soil microorganisms are responsible for nutrient recycling (decomposing residues) and other soil building and maintaining activities. Mixed culture of beneficial microorganisms such as photosynthetic bacteria (Rhodopseudomonas sp), lactic acid bacteria (lactobacillus sp.), yeast (saccharomyces sp.) and fermenting fungi can positively improve the soil fertility as well as plant productivity.

Animals and some other animals (hedgehog, mole, toad, dragonfly…) may, by their actions, improve conditions in various growing situations, and in such cases are also beneficials. Birds and some other animals assist in the spread of seeds by ingesting the fruits and berries of plants, then depositing the seeds in their droppings.

Plants Plants that perform positive functions can also be considered beneficials ( is one technique based on principle of beneficial plants).

Beneficial organisms are divided roughly into three groups:

- Predators: kill other animals for their nourishment - Parasitoids (robber parasitoids): who settle in or on the body of another species, live of their tissues and organs, which leads to death of their hosts - Parasites: live in the body of another species, live of their tissues and organs without compromising their life.

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In agriculture, controversy surrounds the concept of beneficial insects. Much of this has to do with the effect of agrichemicals (, and large quantities of synthetic fertilizers) on what are considered beneficials. Citing the reduction or elimination of various organisms as a side effect of agrichemical-based farming, some argue that critical damage is being done to the , to the point where conventional agriculture is unsustainable. For example, if populations are reduced by insecticides aimed at other pests, pollination is inhibited and crops don't appear. If soil microorganisms are killed off, natural soil regeneration is inhibited, and reliance on mechanical and chemical inputs to keep the soil viable is increased. The longer term impact of these conditions has not been determined.

The aim of biological control is to regulate or naturally control the pest populations. It is estimated that around 60 - 80% of the pests are indigenous species, other pests have been with the aim of biological control transferred from one area to another area and are known as invasive non-native species.

Biological Control is divided into:

1. Classical biological control: purposive input of non-native beneficial organisms 2. Augmentation: mass multiplication and targeted release of beneficial organisms with the purpose of exterminating pests 3. Protective biological control: preservation of existing beneficial organisms in an environment, while promoting keeping of native beneficial organisms and their protection. A preventive biological control differs from the other two in that way that there is no input of beneficials into the environment. It rather encourages the reproduction of existing useful organisms and is trying to create an environment in which the beneficials are bred in order to maintain a balance between pests and beneficial organisms.

PRACTICE:

1. Translate. arachnids predator maintenance of the soil tissue decomposing agrichemicals ingesting augmentation

2. Explain in English.

 beneficial / pest

 parasites

 invasive species

 biological control

Viri: http://en.wikipedia.org/wiki/Beneficial_organism http://www.mizs.gov.si/fileadmin/mizs.gov.si/pageuploads/podrocje/vs/Gradiva_ESS/Impletum/IMPLETUM_331UPRAVL JANJE_Gojenje_Gregori.pdf http://entomology.k-state.edu/extension/insect-information/beneficial-organisms/

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