Cymbidium diseases and control methods
As an elegant traditional China orchid variety, Moran is deeply loved by orchid farmers for its unique leaf appearance. However, during the maintenance process, diseases such as foliar spots and root rot frequently plague growers. This paper provides operable solutions for three typical Cymbidium diseases, from symptom identification to systematic prevention and control. Key points for the prevention and control of Cymbidium white blight. Characteristics of mycelial spread This disease is commonly known as "mycosis" and has a high incidence during the plum rainy season. In the early stage, spider white hyphae can be seen at the base of the leaf and can spread to the entire pseudobulb within 48 hours. Accompanied by the characteristic sour smell, failure to treat it in time will lead to plant lodging and death. Three-step treatment plan ① Emergency removal: Immediately remove the plant when the mycelium is found, and wash the residual plant material with running water ② Focus treatment: Remove the black false bulbs, soak them in 50% carbendazim 200 times solution for 30 minutes ③ Change the pot and regenerate: Using new plants disinfected by steam, combined with 500 times of pentachloronitrobenzene irrigating roots to systematically prevent and control the development of black spot disease. The disease often occurs during the transition period of summer and autumn. Needle-like brown spots appear on the leaves in the early stage, which expands with the rise of temperature. Concentric circles with a diameter of 3-5 mm. It is worth noting that new buds wilted 72 hours after infection. Three-dimensional prevention and control strategy Physical control: Maintain air circulation at 10-15 o'clock every day, and control humidity at 65%-75% Chemical control: Alternate use of mancozeb and difenoconazole, 7 days/time for 3 consecutive weeks Environmental management: Build a rainproof canopy in the rainy season, and residual water droplets on the leaves need to evaporate within 2 hours. The pathogen invades through ramet wounds or insect bite gaps, causing transparent leaf lesions within 2-3 days. Especially in an environment of 28-32 ° C, the reproduction speed of bacteria is tripled. Three-level prevention mechanism Before planting: tools are disinfected at high temperature, and the incision is coated with charcoal powder. Growth period: spraying agricultural streptomycin every 15 days from April to August. Protection during rainy season: spraying kasugamycin immediately after heavy rain, and using additional calcium and magnesium fertilizers to strengthen the cell wall. By establishing a disease early warning system and standardizing maintenance procedures, the risk of disease in Cymbidium can be significantly reduced. Growers are advised to establish a maintenance log to record temperature and humidity changes and medication cycles, and combine it with regular pot turning inspections to keep the classic national orchid alive forever.