Common Diseases and Control Methods of Sedum sarmentosum
As a representative of the Crassulaceae family of succulent plants, Sedum sarmentosum is deeply favored by gardening enthusiasts for its lush, creeping form. However, under high temperature and humidity conditions, fungal diseases such as gray mold, (T-J) disease, and powdery mildew frequently occur, severely affecting the ornamental value and survival rate of the plant. This article systematically sorts out the identification characteristics and key points of prevention and control for the three common diseases, helping you create healthy plants.
Gray Mold Control System for Sedum sarmentosum
Symptom Identification and Transmission Pathways
The disease is prone to occur at temperatures between 15-25°C and relative humidity above 90%. Initially, the leaves show oil-soaked brown spots, which expand to grayish-white necrotic lesions within 48 hours, with a gray mold layer forming at the stem nodes. It can be transmitted across regions through irrigation water and tool contact.
Comprehensive Management Plan
In addition to promptly removing diseased leaves, it is recommended to use Bacillus subtilis (10^8 CFU/g) mixed with seaweed fertilizer at a ratio of 1:800 for spraying. This can inhibit the proliferation of pathogenic bacteria and also enhance the plant's resistance to stress. Before the rainy season, use a 200x diluted bamboo vinegar solution for environmental disinfection.
Key Points for Preventing and Controlling (T-J) Disease in Sedum sarmentosum
Disease Development Patterns
(T-J) pathogen (Colletotrichum spp.) has the strongest infectivity at temperatures between 28-32°C. Initially, it appears as brown sunken spots on the leaf edges, later forming concentric ring-shaped lesions. Research shows that excessive application of ammonium nitrogen fertilizer can increase the incidence rate by 47%.
Ecological Control Strategy
It is recommended to use diatomite substrates (pH 6.2-6.8) for cultivation, combined with foliar application of amino-oligosaccharides. At the early stage of the disease, use a mixture of 25% pyraclostrobin emulsion (3000x) and 5% validamycin wettable powder (1500x) to interrupt the germination of pathogen spores.
Systematic Control of Powdery Mildew in Sedum sarmentosum
Pathogen Characteristics Analysis
The powdery mildew pathogen (Erysiphe polygoni) can infect at temperatures between 10-30°C, with the optimal relative humidity being 40-80%. Unlike other diseases, its conidiospores have drought resistance and can survive in a dry environment for over 28 days.
Biological Control Plan
It is recommended to use a compound formulation of baking soda (sodium bicarbonate) 2g/L + neem oil 5ml/L, sprayed once a week. Experimental data show that this formulation can achieve a mycelium dissolution rate of 92% without chemical residues.
Establishing a comprehensive disease control system requires starting from three aspects: optimization of cultivation substrates, microenvironment regulation, and biological control. It is recommended to use EM bacteria solution to improve the soil every quarter, combined with smart temperature and humidity monitoring equipment to stabilize the environmental humidity between 65%-75%. Regularly use multispectral detectors for early disease screening to achieve precise control.