Comparison of characteristics of botanical pesticides and chemical pesticides:
Botanical pesticides are biological pesticides that use active substances extracted from plants with herbicidal, antibacterial, and insecticidal effects through indirect processing or direct use.
The active ingredients of botanical pesticides are naturally occurring substances in nature, mainly composed of C, H, O, and other elements, which degrade quickly after use and have no environmental pollution. Chemical pesticides are artificially designed and synthesized active substances with insecticidal, bactericidal, herbicidal, and other functions and their active ingredients do not exist naturally in nature.
The main features and differences between the two are:
1. Botanical pesticides have good environmental compatibility, fast degradation in the field, and no risk of pesticide residues.
For example, the digestion half-life of marine in pakchoi field soil is 1.4~1.6d, and the half-life in several typical soils such as black soil in Northeast China is 4.1~9.8d (soil contains microorganisms) and 11.6~13.7d (soil does not contain microorganisms) ), microorganisms in the environment are conducive to the degradation of botanical pesticides.
However, chemical pesticides degrade slowly after use, which poses a great risk of environmental pollution, and it is easy to cause excessive pesticide residues in agricultural products.
2. Botanical pesticides contain a variety of effective components, with various modes of action and target sites, and it is not easy to produce drug resistance during use.
For example, pyrethrin is a mixture of six insecticidal components, including pyrethrin I, pyrethrin II, cinerin I, cinerin II, jasmonic I, and jasmonic II.
The active components of fenugreek include fenugreek I, fenugreek II, fenugreek III, fenugreek IV, and fenugreek Ⅴ, of which fenugreek I has antifeedant effect, bitter taste Epiphyllin II and III have stomach poisoning and contact killing effects, epiphyllin IV has anesthesia effect, and epiphyllin V mainly acts on the plasma membrane and endomembrane system of midgut intestinal wall cells in insects, causing the cell membrane to lose its inherent barrier function. Osmotic imbalance, organelle damage, loss of normal physiological functions.
However, chemical pesticides have a single site of action and long-term use can easily lead to drug resistance. At the same time, because different drugs have the same site of action, cross-resistance will occur between drugs.
3. Botanical pesticides have strong target selectivity and are safe to natural enemies. Chemical pesticides, especially chemical pesticides, have a broad spectrum of insecticides. While killing pests, they will harm natural enemies.
4. The effect of botanical pesticides is slow, and the quick effect is not as good as that of chemical pesticides.
5. Most of the botanical pesticides have no systemic properties, while some chemical pesticides have good systemic properties.
Grasp the period of use:
The use of botanical pesticides should focus on pre-prevention, initial preventive treatment, and post-treatment use. Prevent diseases and insect pests before they occur, and use drugs to prevent and control them in the early stage. During the peak period, use chemical pesticides with good quick-acting effects to control the damage in time, and then apply botanical pesticides to delay drug resistance and reduce the risk of pesticide residues.
Master spray technology:
The systemic absorption of botanical pesticides is not ideal, so it is required to spray evenly on the front and back during the use process to ensure that it is sprayed on all parts of the crop, in order to effectively improve the effect of insecticidal and disease treatment.
Select the usage environment:
Because botanical pesticides are easily degraded and their efficacy is greatly affected by environmental factors, use them in the morning and evening as far as possible to avoid the effect of ultraviolet rays on the efficacy.
To sum up, in order to better improve the effect of botanical pesticides and give full play to the advantages of high efficiency, low toxicity and low residues of botanical pesticides, we need to fully understand the characteristics of botanical pesticides, and determine the appropriate use technology according to their characteristics. Prevention, preventive treatment and treatment are used to play the role of botanical pesticides to ensure environmental safety, human and animal safety, crop safety and agricultural product safety.