Occurrence and Control of Strawberry Powdery Mildew in Greenhouse
Vitamins are a class of organic compounds necessary to maintain good health. This kind of substance is neither a raw material for body tissue nor a source of energy in the body, but a kind of regulating substance, which plays an important role in material metabolism. These substances are often supplied from food because they are not synthesized or are insufficiently synthesized in the body, although they are rarely needed. Vitamin Excellent Health Products Co.,Ltd. , http://www.sino-excellent.com
First, the disease symptoms of the disease mainly harm strawberry leaves, petioles, flowers, stems and fruit. The initial infestation by leaf as a white powder near the small circular spot in the dorsal stellate and stems, the obvious extension to the surrounding an edge contiguous white powder. In severe cases, the whole leaf is covered with white powder, and the leaf margins are curled up and deformed. The leafy material becomes brittle, and finally the diseased leaves gradually turn brown. The victim can not open or flower buds abnormal. Early fruit damage, young fruit development, the surface was covered with white powder, seriously affecting the quality of berry.
Second, the incidence of factors due to high temperature in the greenhouse, the air is relatively high humidity, poor lighting, poor ventilation, powdery mildew is relatively early and serious strawberry incidence. It is generally issued in mid-October (before cap filming), and it is prosperous until late December. Insufficient base fertilizer, lack of water in the soil, resulting in debilitating plant growth; or excessive watering, excessive nitrogen fertilizer, and leggy plants, are all conducive to the occurrence of powdery mildew. Single species, and years of planting, are likely to cause the epidemic of powdery mildew.
Third, comprehensive prevention
1. Select disease-resistant varieties to introduce varieties with strong resistance to disease, and rotate planting with the local planting varieties.
2. Strengthen cultivation and management measures 1 Before transplanting, strawberry fields should be ploughed and turned over, and greenhouses, soil, and transplanting seedlings should be disinfected so as to reduce primary bacterial sources; weeding should be performed before mulching, in order to reduce weeds as intermediates in powdery mildew. The role of; strawberries should be removed during the timely removal of old leaves, diseased leaves and fruit, timely removal of diseased plants, and clear the Tanabe rotten branches rotten leaves. 2 Breeding strong seedlings, timely transplanting; reasonable dense planting, to ensure the appropriate strains, spacing; fertilization to apply sufficient organic fertilizer as a base fertilizer, increased phosphorus and potassium fertilizers, improve plant resistance. 3 do a good job in the ventilation of greenhouses, pay attention to drainage after the rain, reduce the humidity in the field, reduce the infection of pathogens. 4 reform cultivation system, implement a one-year planting.
3, chemical control should be carried out in the early stages of the disease, pharmaceuticals can choose to use 10% Shigeo WG1000-1500 times, 50% of myclobutanil EC2000-3000 times, 12.5% ​​gram fungus WP15-25 grams and other weekly spray 1, even spray 3 Can be times, pay attention to the best alternate use of several agents to reduce the resistance of bacteria.
Vitamins, also known as vitamins, are, in popular terms, substances that sustain life, are a class of organic substances necessary to maintain human life, and are also important active substances for maintaining human health. Vitamins are low in the body, but they are indispensable. Although the chemical structures and properties of various vitamins are different, they have the following in common:
1 vitamins are present in food in the form of provitamins;
2 vitamins do not constitute a component of body tissues and cells, it does not produce energy, its role is mainly involved in the regulation of the body's metabolism;
3 Most of the vitamins, the body can not be synthesized or the amount of synthesis is insufficient, can not meet the needs of the body, must be obtained through food;
4 The human body needs a small amount of vitamins. The daily dose is usually calculated in milligrams or micrograms, but once it is lacking, it will cause the corresponding Vitamin deficiency, which will cause damage to human health;
Vitamins are different from carbohydrates, fats and proteins. They are only a small percentage of natural foods, but they are necessary for the human body. Some vitamins such as B6.K can be synthesized by bacteria in the intestines of animals, and the amount of synthesis can meet the needs of animals. Animal cells can convert tryptophan into niacin (a type B vitamin), but the amount of production is not enough; vitamin C can be synthesized by other animals except primates and guinea pigs. Plants and most microorganisms can synthesize vitamins themselves, without having to be supplied from outside the body. Many vitamins are part of a prosthetic or coenzyme.
Vitamins are some small amounts of organic compounds necessary for human and animal nutrition and growth. They are extremely important for the metabolism, growth, development and health of the body. If you lack a certain vitamin for a long time, it will cause physiological dysfunction and cause certain diseases. Generally obtained from food. There are dozens of kinds found at this stage, such as Vitamin A, vitamin B, vitamin C and so on.
Vitamins are essential organic compounds in the metabolism of the human body. The human body is like an extremely complex chemical plant, constantly carrying out various biochemical reactions. The reaction is closely related to the catalytic action of the enzyme. Enzymes must be enzymatically active in order to produce activity. Many vitamins are known to be coenzymes of enzymes or constituent molecules of coenzymes. Therefore, vitamins are important substances for maintaining and regulating the normal metabolism of the body. It can be considered that the best vitamins are in the form of "biologically active substances" and are present in human tissues.