How to control diseases and pests of water chestnut? A detailed explanation of the latest control methods
Water chestnut is a common fruit and vegetable in daily life. It can be eaten raw as a fruit, or stir-fried or used in soup as a vegetable. It is rich in nutrients and has excellent dietary therapeutic effects, and is deeply loved by both young and old. It is planted in all major regions of our country. But what troubles growers is diseases and pests, which seriously affect the yield and quality of water chestnut and reduce growers' economic returns. So what diseases and pests harm water chestnut, and how should they be controlled? Let's take a look together with Qinnong Web below.
1. Pathogenic diseases
The main pathogenic diseases of water chestnut are water chestnut stem blight, water chestnut wilt, and water chestnut corm stem rot. These three diseases generally break out in September-October, and plants may also be infected by multiple diseases at the same time. Water chestnut stem blight is also called water chestnut plague. After infection, the plant does not form corms or forms small corms, affecting yield. In severe cases, it may cause total crop failure. When the disease occurs, water-soaked lesions appear on the stems. As the disease develops, the lesions expand, and finally the stems wither and lodge. Water chestnut wilt is similar to water chestnut stem blight. When the disease occurs, gray blighted spots with depressions appear on the stems, and the lesions expand and merge. The harm to planting is relatively small, and the plant can still grow and develop normally. When water chestnut corm stem rot occurs, the corms also turn yellow and withered, the plant stems are short and thin, and dark gray lesions appear. As the disease develops, the tissue at the lesions becomes soft and breaks easily. When humidity is relatively high, the diseased area rots.
Control methods: For pathogenic diseases, prevention should be given priority. In the early stage, do a good job of soil disinfection and sterilization to reduce pathogens, increase the application of phosphorus and potassium fertilizers to improve plant disease resistance, and adopt crop rotation methods with reasonable rotation to reduce the severity of the disease. Once disease is found, control it promptly. For stem blight and wilt, 50% carbendazim 600-fold solution can be used together with other agents for spraying control, while for corm stem rot, 40% quintozene powder 500-600-fold solution can be used for spraying control.
2. Physiological diseases
The main physiological disease is the red tail phenomenon. When it occurs, the symptoms are red tails without seedling drying, or the top internode of the stem dries up. The main cause is crop rotation and a lack of trace elements such as boron, zinc, and iron in the soil.
Control methods: Use reasonable crop rotation. When fertilizing, add 2 kg each of borax and zinc sulfate to prevent the occurrence of this disease. After it occurs, potassium dihydrogen phosphate can be diluted with water and sprayed as a foliar fertilizer, with excellent results.
3. Insect pests
Water chestnut has relatively few insect pests. The main insect pest is the white stem borer. White stem borers generally damage water chestnut as third- and fourth-generation larvae. The larvae bore and feed inside the diseased stems, causing obstruction of water chestnut prevention and water transport, and finally leading to stem rot, causing reduced yield and lower quality.
Control methods: In winter, irrigate the paddy field to drown the overwintering stem borers and reduce the insect source. During the peak period of the pest, insecticide can be used for control, but pay attention to the dosage and concentration to avoid harming water chestnut growth. Its natural enemies, Trichogramma and red ants, can also be used for control.
The above are the water chestnut disease and pest control methods brought to you by Qinnong Web. We hope they can help you. To learn more about water chestnut cultivation knowledge, please stay tuned to Qinnong Web.