Plant-derived pesticides refer to pesticides whose active ingredients are derived from plant organisms. Plant-derived pesticides are environmentally friendly in the control of crop pests and diseases, generally have low toxicity, and are not easy to cause resistance to pests and diseases. With the improvement of people's living standards and the awareness of environmental protection, people are paying more and more attention to the negative effects of pesticide use. In view of the excessive investment in chemical agricultural materials, the deterioration of environmental quality, the backward processing of pesticides, and the high residue after use, the development of high biological activity, low toxicity and environment from the perspective of sustainable agricultural development, efficient use of resources, environment and food safety Green pesticides with good compatibility - plant-derived pesticides are of great significance.
The natural compound osthole is a coumarin compound extracted from traditional Chinese herbal medicines such as snake bed and eucommia. It is widely used in medicine. In the past ten years, the study has found that osthole coumarin compounds have a wide range of pharmacological effects on the cardiovascular system, nervous system, endocrine system, immune system, skeletal system and respiratory system.
In addition to the active core structure of coumarin and the pyranone ring, osthole also has an important pesticide active gene, isopentenyl structure, which exhibits unique insecticidal and bacteriostatic activity. Studies have shown that osthole not only has effects on pests such as cabbage caterpillar, diamondback moth, aphid and larvae, but also on plant pathogenic fungi such as cucumber powdery mildew, grape downy mildew, Phytophthora capsici, and wheat scab. Significant inhibition.
1 Highly active, slightly toxic, no residue.
2 High efficiency. Osthole inhibits the insecticidal activity of chitin deposits on the walls of insects and fungal cells, and also inhibits the spore production, germination, adhesion, invasion and sprouting of pathogenic bacteria and the nervous system acting on pests. When only 1 gram of osthole pure product is sprayed per 667 square meters, the pest control effect can reach 85% to 95%, which is equivalent to the effect of chemical pesticides. Breaking through the past, bio-pesticide is environmentally friendly but not efficient.
3 No residue. The residue in the cucumber fruit was not detected 3 days after the drug, so the residual time in the environment was short and the environment was not polluted.
The insecticidal mechanism of osthole is expressed as inhibition of insect acetylcholinesterase, affecting the nervous system, leading to non-functional contraction of the muscles of the pest, and eventually death. The bactericidal mechanism inhibits the growth of calcium ions and the spore germination by inhibiting the absorption of calcium ions, and hinders the deposition of chitin in the cell wall of the cells. The egg mass of the night moth is mainly composed of chitin. The effect of osthole on the egg mass of the night moth is likely to dissolve the villi on the egg mass of the night moth, reducing the adhesion of the egg and causing the hatching rate to decrease.
Application in vegetable production
1 Control cabbage caterpillars. For every 667 square meters, use 0.4% emulsifiable oil 80ml ~ 120ml to spray evenly from 50 liters to 75 liters of water. The effect period is about 7 days, which is safe for crops.
2 Control aphids. It was sprayed with a 1% osthole water emulsion 400 times solution.
3 Control cucumber, pumpkin, strawberry powdery mildew. Control with 1% osthole water emulsion 400 times liquid ~ 500 times liquid spray.