How to prevent and control Chinese cabbage pests and diseases, Chinese cabbage pest and disease control techniques
Chinese cabbage is a common vegetable in northern my country. Chinese cabbage tastes good and is very nutritious. However, Chinese cabbage is very susceptible to pests and diseases during the planting and growth period, resulting in reduced yields. Therefore, it is The problem of pests and diseases in cabbage should be taken seriously. So, how to prevent and control Chinese cabbage pests and diseases? Today, the editor will introduce to you the pest control technology of Chinese cabbage.
Chinese cabbage pest control technology 1 - disease control
1. Downy mildew. It mainly damages the leaves, with yellow spots initially appearing on the leaf surface, which turn into light brown after enlargement. When the humidity in the field is high, white mold will appear on the back of the leaves, and eventually the leaves will turn yellow. The temperature fluctuates high and low, and the temperature difference between day and night is large. It is easy to occur when the temperature is high and there is lots of dew and fog. Sowing too early, too densely, and using Banedabika high-nitrogen fertilizer instead will cause poor drainage in the field. In the early stage of the disease, 40% aluminum ethylphosphonate 800 times solution, 58% metalaxyl manganese zinc 500 times solution or 1.5% sulfatecarb 1000 times solution can be sprayed on the leaves, once a week, and spray 2-3 times.
2. Soft rot. The disease mostly occurs during the bulbing stage. At the initial stage of the disease, water-soaked soft rot occurs at the base of the peripheral leaves or shortened stems. Then the leaves wilt and collapse, and the leaf bulbs are exposed. Sometimes, the shortened stems begin to rot outward, becoming sticky and smelly. taste. The germs spread mainly through insects, rain or irrigation water, and invade through wounds. During the bulbing period, the temperature is low, there is heavy rain and water accumulation, and the plant growth is weak, etc., all of which are prone to the disease. Adopting high-ridge mulching cultivation and implementing crop rotation and other measures can reduce the incidence. At the same time, excessive squatting and flood irrigation should be prevented to reduce wounds and mechanical damage. In the early stage of the disease, 72% agricultural streptomycin 3000 times solution, 3% Kejikang 1000 times solution or 20% Longkebacter 500 times solution can be sprayed alternately, once a week, and sprayed 2-3 times continuously.
3. Viral diseases. Symptoms are divided into mosaic type and shrunken type. When cabbage is exposed to high temperature and drought after sowing, root growth and development are inhibited and disease resistance is reduced. In addition, high temperature and drought are conducive to the occurrence of aphids. Cabbage virus disease is transmitted by aphids, so it is very important to control aphids. You can spray 10% imidacloprid 2000 times once every 7-10 days for 2-3 times. After the cabbage becomes ill, spray 1.5% Phytopathogen No. 2 800 times solution or virus killer foliar spray once a week for 2-3 times.
4. Black spot disease. The disease begins on the rosette leaves, producing nearly circular gray-brown lesions with obvious concentric rings. In the early stage of the disease, spray 50% carbendazim 500 times once every 5-7 days, and spray 2-3 times continuously.
5. Dry heartburn: It usually begins to occur in the rosette stage of cabbage. Young leaves show dry edges. The symptoms become obvious at the bulbing stage. The upper parts of the leaves gradually become dry and yellow, and the mesophyll becomes dry paper-like. The leaf veins are yellow-brown to dark black, and the diseased site is mainly in the middle of the leaf bulb. This disease is a physiological disease, mainly caused by the lack of calcium and manganese nutrients. Prevention and control measures: (1) Apply more organic fertilizer; (2) Chemical control: Use 0.7% manganese sulfate plus Green Fenwei No. 3 spray during the seedling stage, rosette stage or core wrapping stage of cabbage.
6. Vitiligo. It mainly damages the leaves. When the disease occurs, many gray-white nearly round lesions appear scattered on the leaf surface, with 1-2 irregular rings in the center. The final lesions are white, translucent, and like a fire. Avoiding continuous cropping, applying more base fertilizers, and preventing water accumulation in the fields can reduce the occurrence of diseases. In the early stage of the disease, use 50% carbendazim 500 times solution or 70% mancozeb 500 times solution for prevention and control. Spray once every 10 days and spray 2-3 times continuously.
Chinese cabbage pest control technology 2 - Pest control
1. Aphids and whiteflies
(1) Damage characteristics: Both are adults and nymphs Suckling the sap of Chinese cabbage can cause the damaged leaves to become chlorotic, yellow, wilted, or even the entire plant to die. The secreted honeydew seriously pollutes the leaves, causing mildew and making the cabbage lose its edible value. In addition, viral diseases can also be transmitted.
(2) Prevention and control methods: ①Physical method: Using the yellowing tendency of aphids and whiteflies, set up yellow boards in the field to trap and kill them. Set 20-25 yellow boards per acre and fix them on wooden sticks. Insert it in the vegetable field, and the height should be 20cm higher than the bottom of the yellow board above the top of the plant; ② Biological method: 3% pyrethrin microcapsule suspension 45 ml of biological agent can be sprayed for control; ③ Chemical method: 10% imidacloprid wettable can be used Use powder 2000 times liquid, Delik 1500 times liquid, and 98% Bataan wettable powder 2500 times liquid alternately spray for prevention and control, once a week, spray 2-3 times in a row, pay attention to morning and evening use.
2. Rapeseed caterpillar, Spodoptera exigua and Diamondback moth
(1) Damage characteristics: All three pests cause damage by larvae eating leaves. After the third instar of the rapae, the entire leaf can be eaten away , only the leaf veins are the most serious damage, seriously affecting the growth and wrapping of cabbage, resulting in reduced yields; beet armyworm mainly gathers newly hatched larvae on the back of leaves to spin silk and form webs, feeding on the leaf mesophyses, leaving small transparent holes in the epidermis. After 4 years of age, the food intake increases greatly, and the leaves will be eaten into holes or nicks. In severe cases, only the veins and petioles are left, which has a greater impact on yield and quality. Diamondback moths can eat vegetable leaves into holes and nicks, and in severe cases, the entire leaf will be eaten. It is reticular in shape and often causes damage to the central leaves during the seedling stage, affecting the cabbage filling.
(2) Prevention and control methods: ①Physical method: Make use of the phototaxis of the pests, and set up a frequency vibration insecticidal lamp or black light lamp every 40-50 acres in the field to trap the pests; beet exigua moth can also be used , diamondback moth, etc. to sex pheromones, place a set of sex attractants in each acre of the field to trap the pests; ② Biological methods: Use biological agents BT250-500 times liquid spray to control pests in their early stages; ③ Chemical methods : It can be controlled by alternate spraying of 15% Anta Suspended Agent 3000 times, Andal 1500-2000 times, and 4.5% high-efficiency cypermethrin emulsifiable concentrate 1500-2000 times.
Prompt control of Chinese cabbage pests and diseases can not only ensure the quality of Chinese cabbage, but also ensure the yield per mu!