Bordeaux liquid is not a fungicide, but its own does […]
Bordeaux liquid is not a fungicide, but its own does not have a bactericidal effect, so what is the principle of the role of Bordeaux liquid? What should vegetables pay attention to when using Bordeaux liquid? The next step is to follow us and learn more about this specific knowledge.
Principle of action of Bordeaux liquid.
The Bordeaux liquid itself does not have a bactericidal effect, and when it is sprayed on the surface of the plant, it is adsorbed to the crop due to its adhesion. And plants secrete acidic fluid during metabolism, together with the acid secret by bacteria during the invasion of plant cells, so that a small amount of basic copper sulphate in the Bordeaux fluid is converted into soluble copper sulfate, thus producing a small number of copper ions (Cu2+), Cu2+ into the pathogenic cells, causing the protein in the cell to solidify. At the same time, Cu2+ can also destroy an enzyme in its cells, thus preventing metabolic action in the bacterial body. Under the influence of these two effects, i.e., the bacteria can be poisoned to death.
Methods of using Bordeaux liquid in vegetables.
The concentration of Bordeaux liquid used on vegetables is generally one part of copper sulfate, one part raw lime, 200 parts water. Melons are sensitive to lime, and it is advisable to use one part copper sulfate, 0.5 parts lime, 200 parts water. Different concentrations should be used for different types of vegetables and stages of fertility, and the vegetables are less adaptable to the Bordeaux solution in the seedling stage, and the concentration should be reduced appropriately.
The use of Bordeaux liquid in vegetables requires attention to several ways.
First: The Bordeaux liquid is alkaline and cannot be mixed with acidic agents.
Second: Bordeaux liquid should be used now, can not be stored, left for too long, produce precipitation, reduce the efficacy.
Third: Bordeaux fluid is a plant protection agent, so it should be sprayed before or at the beginning of the disease.
Fourth: In the morning dewy or wet and rainy weather, or sunny day temperature above 30 ℃ at noon, should avoid the application of Bordeaux liquid, otherwise easy to occur.
The last and most important point, vegetables in the use of Bordeaux liquid, in order to reduce pests need to do. The vegetables can not be used within half a month before harvesting Bordeaux liquid; 15-20 days can not be reapplied loosening agent, 15-30 days can not be applied, lithophone agent.