Biological pesticides and biological control

Biological pesticides are pesticides that are made from living organisms, mainly microorganisms and their metabolites. Biological pesticides include biochemical pesticides and microbial pesticides. Biochemical pesticides must meet two conditions: they are not directly toxic to the control subjects, but only have special effects such as regulating growth, interfering with mating or attracting; they must be natural compounds. If they are artificially synthesized, their structures must be the same as those of natural compounds. Difference in body proportions. Such pesticides contain pheromones, hormones, natural plant growth regulators, and insect growth regulators and enzymes. Certain plant-derived pesticides such as alizarin, rotenone, nicotine, natural pyrethrins and Chinese herbal medicines should also be used as biological pesticides. Microbial pesticides include those naturally produced by bacteria, fungi, viruses, and the like to prevent pests, insects, grasses, rats, and other harmful organisms, such as Bacillus thuringiensis, nuclear polyhedrosis virus, and Jinggangmycin. Biological control refers to the use of beneficial organisms and their metabolites and genetic products to control pests. The biological control of agricultural pests includes the use of pests to treat pests, the use of bacteria to treat pests and the use of other beneficial animals; the biological control of plant diseases is mainly the use of beneficial microorganisms, through competition among organisms, antibacterial effects, heavy parasitic effects, cross protection and Induces disease resistance, etc. to suppress the survival and activity of certain pathogens. The broad concept of biological control also includes the application of insect hormones such as juvenile hormones, microbial pesticides such as BT EC, antibacterial substances such as Jinggangmycin and Nongxin, and the improvement of host plants' resistance to pests and diseases. Biological control has many advantages over chemical control, such as safety to humans and animals, no pollution to the environment, no resistance, and only killing or inhibiting control objects, therefore, it can participate in the regulation of the ecological environment, maintain the ecological balance, and play a long The effect of the effect. The disadvantages are that the control effect is vulnerable to environmental factors, and the effect is not as fast as the chemical control. The technical difficulty of artificial propagation and cultivation of beneficial organisms is high. The species of natural enemies that can be used for large-scale release are few, and most natural enemies are predatory and parasitic to pests. Selective, narrow range of effects. Biological control is an important part of the comprehensive management of pests. It is a prevention and control measure that is worth advocating and has a great future for development.