This is a method to reduce the population density of pests and weeds. It uses the relationship between biological species to suppress another or another creature with one or another creature. Its greatest advantage is that it does not pollute the environment, which is incomparable to non-biological pest control methods such as pesticides. There are many methods of biological control.
Due to the long-term use of chemical pesticides, some pests have developed strong drug resistance, and many natural enemies of pests have been killed in large numbers, resulting in some pests being very rampant. A variety of chemical pesticides seriously pollute water, air and soil, and enter the human body through the food chain, endangering people's health.
Measures to prevent and control organisms that are harmful to agriculture, storage, buildings and human health by using the ecological phenomena and some biological characteristics of interdependence and mutual restriction among various organisms in the ecosystem.
Biological control has a long history in China. The Southern Vegetation in the Jin Dynasty around 304 AD and Lingyi by Liu Yao in the Tang Dynasty in 877 AD recorded the situation of using mosquitoes to control citrus pests. Since19th century, biological control has developed rapidly in many countries in the world.
Biological control of pests and diseases can effectively avoid the above shortcomings, so it has broad development prospects.
Types of biological pest control
There are three basic biological pest control strategies: input (classical biological control), proliferation and protection.
1, importing
Introduction or traditional biological control involves introducing natural enemies of pests into new places where they will not naturally appear. Early examples are usually unofficial, not based on research, and some introduced species have become serious pests themselves.
In order to control pests most effectively, biological control agents need to have clustering ability so as to keep up with the spatial and temporal changes of habitats. If the agent is persistent, so that even if the target species does not exist temporarily, it can maintain its population. If it is an opportunistic forager, it can quickly use the pest population, then control is the best.
Step 2 increase
Enhancement includes the supplementary release of natural enemies that occur in specific areas, thereby increasing the natural population there. In the release of inoculation, a small amount of control agent is released every once in a while to make it multiply, so as to establish long-term control, so as to control pests at a low level, which constitutes prevention rather than treatment. In contrast, in submerged release, a large amount of release is to quickly reduce the population of harmful pests and correct the existing problems.
Enhancement may be effective, but it is not guaranteed to be effective, depending on the exact details of the interaction between each pest and control agent.
An example of inoculation release occurred in the horticultural production of several crops in greenhouse. Parasitic bees regularly release Taiwan Province aphids to control whiteflies in greenhouses, while phytophagous mites are used to control tetranychus urticae.
Step 3 protect
Protecting the existing natural enemies in the environment is the third method of biological pest control. Natural enemies have adapted to the habitat and target pests, and protecting them is simple and cost-effective, just like planting honey crops on the edge of rice fields.
These natural enemies who provide nectar to feed parasitic bees and rice planthopper pests have proved to be very effective (reducing pest density 10 times or even 100 times), reducing the pesticide sprayed by farmers by 70% and increasing the yield by 5%.
Similarly, aphid predators were found in the grass of hedgerows on the edge of fields in England, but they spread too slowly to reach the center of the fields. By planting grass one meter wide in the center of the field to improve control, natural enemies of aphids can spend the winter there.
Refer to the above? Baidu encyclopedia-biological control