How to Identify and Control Bacterial Diseases in Vegetables
Many people cannot tell fungal diseases apart from bacterial diseases, and this is a fairly important point when growing vegetables, because once you cannot distinguish them, it becomes difficult to treat them with the right remedy. Today let us first understand what bacterial diseases are and how to prevent and control them when growing vegetables.
1. What are bacterial diseases?
Bacterial diseases are diseases caused by infection with bacterial pathogens, such as soft rot, canker, and bacterial wilt. The bacteria that infect plants are all rod-shaped bacteria, most of which have one to several flagella. They can invade through natural openings (stomata, lenticels, hydathodes, etc.) and wounds, spread by flowing water, rainwater, insects, and the like, overwinter in diseased plant residues, seeds, and soil, and are prone to causing disease under conditions of high temperature and high humidity.
Symptoms: the symptoms produced after plants are infected by bacterial diseases include:
1. Spot type. Among the diseases caused by infection of plants with Pseudomonas bacteria, a considerable number appear as spots. Examples include bacterial brown spot of rice, bacterial angular leaf spot of cucumber, and bacterial angular leaf spot of cotton.
2. Bacterial wilt type. It is generally caused by Pseudomonas bacteria infecting the plant vascular bundles, blocking the transport pathways, and causing the plant stems and leaves to wilt. Examples include bacterial wilt of tomato, bacterial wilt of potato, and bacterial wilt of strawberry.
3. Leaf blight type. Most cases are caused by infection with Xanthomonas bacteria, and after infection the plant ultimately suffers leaf wilt. Examples include bacterial leaf blight of rice, bacterial leaf blight of cucumber, and bacterial leaf blight of konjac.
4. Canker type. It is generally caused by Xanthomonas bacteria infecting plants; in the later stage the lesions become suberized, with raised edges and a sunken center, appearing canker-like. Examples include citrus canker, bacterial blight of vegetable soybean, and bacterial spot of tomato fruit.
5. Deformity type. It is caused by infection with Agrobacterium tumefaciens, causing deformities on the plant roots, root crowns, lateral roots, and branches and stems, appearing as tumor-like swellings. Examples include crown gall of chrysanthemum.
6. Rot type. Most cases are caused by Erwinia bacteria infecting plants and then causing rot. Examples include bacterial soft rot of Chinese cabbage, bacterial soft rot of Solanaceae and Cucurbitaceae crops, and bacterial foot rot of rice.
2. How should bacterial diseases be prevented and controlled when growing vegetables?
1. To control bacterial diseases of vegetables, such as soft rot of Chinese cabbage, bacterial angular leaf spot of cucumber, bacterial blight of kidney bean, and bacterial fruit rot of watermelon, spray with a 100-fold dilution of 3% zhongshengmycin in the early stage of disease onset; depending on the condition, spray once every 7-10 days, for 3-4 consecutive sprays. To control bacterial wilt of Solanaceae crops, use a 1000-fold dilution of 3% zhongshengmycin for root drenching, 400 milliliters per plant; depending on the condition, drench once every 7-10 days, for 3-4 consecutive drenchings. The control effect can reach 99.95%, and it also has a certain yield-increasing effect.
2. To delay resistance and expand the control range, you can use a 600-fold dilution of 4% chunlei zhongshengmycin wettable powder for spraying, to control bacterial diseases such as gummosis of fruit trees and soft rot of Chinese cabbage, with quite good results.