Remedy against tomato late blight
Symptoms: Late blight of tomato can occur from the seedling stage to the end of the season. It damages both the leaves and the stems and fruits. The damage to the leaves and fruits is the heaviest. Generally from the front of the shed to the onset of disease, first invade the leaves and young fruit, and gradually spread to the stems and petioles to make it dark brown, severe plant wilting break. The fruit of the disease was hard and uneven, with a dark greenish oily appearance at the beginning and a dark brown to tan afterwards. In general, the susceptible fruit did not become soft and rot. When the humidity is high, white moulds can be seen at the junction between the front and back of the leaves.
Incidence: Late blight is a low-temperature, high-humidity disease. The air temperature in the greenhouse is 22-24°C during the day and 10-13°C at night. The relative humidity of the air can infect the plants above 80%. In the morning and evening, fog, dew, or drizzle, high humidity, and severe onset. Due to the rapid development of the disease, if it is discovered, vegetable farmers must spray medicine as soon as possible.
Prevention:
1. Choose disease-resistant and disease-resistant varieties, and the serious disease greenhouses must achieve rotation for more than three years, and can rotate with non-sweet potato vegetables.
2. High ridge cover film cultivation; suitable planting density, not too dense, early scaffolding, timely pruning, appropriate removal of the plant's lower leaves, yellow leaves and diseased leaves, improve ventilation and light transmission conditions. The use of formula fertilization techniques, combined use of nitrogen, phosphorus, and potassium fertilizers, increased potash fertilizer can reduce the incidence of disease. Pay attention to reasonable irrigation, avoid flooding irrigation.
3. After exposing the grass curtain every morning, check the leaves and fruits of the tomatoes in the shed. Focus on the 1-2 meters of tomatoes in the front of the shed. Find the central diseased plant and immediately remove the plant or remove the diseased leaves and fruit. , Bring it out of the shed or burn it down, reducing the spread of the field.
4. Temperature and humidity control. The tomato's result period requires daytime temperatures of 25-30°C and nights at 12-15°C. The minimum temperature cannot be lower than 10°C. In the deep winter, when the temperature is low, it must be covered with straw curtains. At the same time, the grass curtains are covered with films. On sunny days, when the room temperature reaches 30°C, the air is released in a timely manner, and when the room temperature is high, the air is released in a short period of time.
5. Scientific medication. Field diseased plants should be removed from the field, and diseased leaves and diseased fruits should be removed. Use 50% Anke manganese zinc WP 500 times, 72% Kelu wettable powder 800X, 72.2% Prokone 800X fluid, or 58 % Rhodamine MnZn WP 500 times spray. The leaves, stems, green fruit, etc. must be sprayed. The middle and lower parts of the plant are the key spray areas and should be used for rotation. Pay attention to the time when fighting drugs must be in the morning. In the afternoon, when the medicine is sprayed, the water does not spread out and the humidity is high, which is detrimental to disease prevention. In case of rainy days, dust or smoke can be used for prevention and control. Dust method: Mu with 5% chlorothalonil dust 1 kg spray powder. Smoke agent method: 45% chlorothalonil smoke agent or 200-250 g smoked shed with 10% fast-king spirit smoke agent.
Shrimp Series,Wild Shrimp,Frozen Pink Shrimp,Frozen Vannamei Shrimp
Zhejiang Zhoushan Jiaze Aquatic Co., Ltd. , https://www.tianjia-aquatics.com