Diseases and Pests of Chinese Cabbage and Their Control
As a new favorite in gardening with both ornamental and edible value, Chinese cabbage is deeply loved for its unique leaf shape and rich nutritional value. However, in the actual planting process, diseases and pests often become the key factors affecting the health of the plants. This article will systematically analyze the common diseases and pests of Chinese cabbage and provide scientific control measures.
Techniques for Controlling Diseases of Chinese Cabbage
Comprehensive Control of Soft Rot Disease
The disease often occurs in high temperature and humidity environments, initially presenting as water-soaked spots on the leaves, which gradually expand into brown rot patches. It is recommended to adopt a three-level protection: ① Soak seeds in 50℃ water for 20 minutes before planting; ② Spray 72% agricultural streptomycin soluble powder at a dilution of 2000 times in the early stage of the disease, and apply three times at 7-day intervals; ③ Pay attention to drainage during the rainy season and maintain a plant spacing of over 30cm for good ventilation.
Scientific Response to Downy Mildew
The appearance of gray-purple mold on the back of the leaves is a typical symptom. This can be controlled by combining biological and chemical methods: apply 5g of Bacillus subtilis per square meter for soil treatment, and alternately use 68% metalaxyl-M zinc water-dispersible granules at a dilution of 600 times and 25% pyraclostrobin suspension at a dilution of 1500 times when the disease occurs, with emphasis on covering the back of the leaves during spraying.
Chinese Cabbage Pest Management Plan
Ecological Control System for Aphids
In addition to the conventional control with 10% imidacloprid wettable powder at a dilution of 2000 times, it is recommended to establish an ecological control system: intercropping with insect-repelling plants such as mint and basil, hanging yellow sticky traps (one per 5 square meters), and releasing natural enemies such as ladybirds to reduce the pest population by over 60%.
Three-dimensional Control of Cabbage Moth
The larvae create nets that cause harm. It is suggested to take the following measures: ① Physical control: Install frequency vibration insect-killing lights (15 per hectare) during the adult stage in May-June; ② Biological control: Release Trichogramma dendrolimi (20,000 per mu) during the egg stage; ③ Chemical control: Use 5% chlorantraniliprole suspension at a dilution of 1000 times, focusing on spraying the heart leaves.
Integrated Management of Cabbage Caterpillars
A three-level prevention and control strategy is adopted: ① Manually remove egg masses every 3 days; ② Spray Bacillus thuringiensis preparation (800 IU/mg) at a dilution of 500 times during the larval stage; ③ Use sex pheromone traps (15 per mu) during the adult stage, combined with planting plants like rosemary to form a protective barrier.
By establishing a plant protection system focusing on prevention and comprehensive management, the disease and pest resistance of Chinese cabbage can be significantly improved. It is recommended that growers practice crop rotation with cruciferous vegetables, maintain a soil pH between 6.0 and 7.0, and apply balanced fertilization (N:P:K = 2:1:3) to reduce the probability of disease and pest occurrence from the source of cultivation, ensuring healthy plant growth.