Protect seedlings from rain by using polyvinyl shelter during rainy season. Isolate or destroy infected plants. For chemical control, the use of thiophanate methyl or benomyl is recommended. Avoid excessive use of organic fertilizer especially mineral manure. Planting media in the pot should be discarded.
Symptoms vary between genus and type of orchid.
On Oncidium, tiny spotsare produced on lower surface of leaves while on most Dendrobiums, yellow circular spots are observed. Destroy infected parts to reduce potential cause of infection. Avoid excessive watering. For control and treatment, spray with benomyl, captafol or vinclozolin. To get effective control, the spray must cover both upper and lower surfaces of leaves.