Penguin powdery mildew prevention in greenhouse
Melon powdery mildew is caused by the two powdery mildews of the Ascomycete subphylum. The wide range of hosts can be used to kill cucumbers, watermelons, melons, pumpkins, and melons, and other melon crops. Initially, the disease began from the lower middle leaves of the plants. Near-circular white powder was formed on the front of the leaves, enlarged into larger pink spots, and finally the whole leaf was covered with a full leaf, and the diseased leaves faded and turned yellow. Finally, it became Brown dry. The pink spots also turn gray, and the surface produces piles of yellow-brown, small-grained spots that eventually turn black, the fruiting body of the pathogen. Symptoms on the stem and petiole are the same as those on the leaf blade. With the diseased body overwintering in the soil and on the surface of the soil, it can also overwinter on greenhouses, greenhouse walls, and scaffolds. It will produce conidia in the following year, and it will spread with the airflow and invade the field repeatedly. Disease temperature is 10 °C ~ 25 °C, high temperature drying and alternating high temperature and high humidity is conducive to the occurrence of disease. The disease is severe at the late growth stage of the plant growth. The disease is difficult to prevent and control: First, the bacteria can adapt to a wide range of humidity. In the case of relative humidity of 10% to 90%, germination can occur. The second is that pathogenic bacteria infect the epidermis in the early stage of infection, when the leaves produce white powder, a large number of conidia and conidial stems have been formed, spraying difficult to control. Black spots have already appeared on the spot, that is, fruiting bodies are produced, and it is even more difficult to control drugs. Therefore, for the prevention and control of powdery mildew, we should adhere to the principle of prevention and comprehensive prevention and control of plant protection, and control the disease before or at the beginning. Prevention methods are as follows: 1. Use resistant varieties. 2. Do a good job in field management. Apply enough base fertilizer and increase phosphorus and potassium fertilizers, especially to prevent defertilization during the late growth period of crops. Ventilation should be paid attention to in the production of greenhouses, and light should be increased to increase the disease resistance of plants. Diseased leaves and sicknesses should be removed promptly and destroyed centrally to reduce the source of overwintering bacteria in the field. 3. Before the melons are planted, the greenhouse disinfection must be carried out. At present, there are two best ways: First, high temperature stuffy shed, and second, the fumigation of drugs. Fumigation is best used sulfur powder plus sawdust. Generally, 1.5 to 2 kg of sulphur powder per mu and 3 to 4 kg of sawdust. Special attention should be paid to the fact that sawdust must be wetted beforehand (to prevent open flames, affecting efficacy, and burning of greenhouses), and then mixed evenly with sulfur, then placed in various spots in the shed to ignite Kaoru overnight. Replant seedlings. 4. Severe sheds of powdery mildew, preferably in rotation with non-cucurbit crops. 5. Chemical control. Chemical control must be early, in the early stages of the disease. Can use 2% of agricultural anti-120 or 2% Wuyimycin (BO-10) agent 200 times, myclobutanil WP 2500-3000 times, 15% triadimem WP 1500 times, 30% Tefu 1500- 2000 times, you can also choose Phenylofen, Pterocycline and other new pesticides, the use of a concentration of 3000 times. In particular, it should be emphasized that this pathogen has a strong ability to adapt to humidity, and it must be prevented from drying out in the field. In addition, according to recent practice, using the bacteria in the saturated humidity, the spores are disintegrated, and when a few spots on the leaves have just been generated, the leaves can be sprayed with 1 to 2 drops of baking soda or salt water, and the water flows downwards. You can. The early prevention effect of this method is very good. Rapid Flu A/B Ag Test Kit (Colloidal Gold) Flu A,Flu B,Antigen,Colloidal Gold,Test Cassette Shenzhen Uni-medica Technology Co.,Ltd , https://www.unimed-global.com