Disease and Pest Control of Dendrobium sphenanthera

Disease control

Black spot

You may be familiar with this disease, as it occurs on many plants. Black dots first appeared on the leaves, and yellow appeared around the dots. But if it is allowed to develop to the later stage, the black dots may connect into a large area. Eventually the entire leaf falls off. This disease basically occurs in spring. Once discovered, it should be treated as soon as possible.

First remove the leaves that have been infected. It is best not to throw away the removed leaves casually. You can choose to burn them and then bury them deeply to prevent the free bacteria from infecting other plants. After processing, use appropriate concentrations of Bordeaux mixture or carbendazim for prevention and control.

Soil pollution

The disease also occurs in spring, and the appearance of the disease is as if the leaf surface is covered with a layer of black powder like soot. This powder affects the part of the leaves that blocks sunlight, which in turn affects their ability to photosynthesize. After discovering this disease, the diseased plants must also be treated, and then sprayed once or twice with a mixture of appropriate doses of carbendazim or malathion emulsion.

Pest Control

Here we introduce a pest, the Philippine shield scale. The symptom of this insect is direct withering of the leaves. Because they will parasitize on the edges or backs of the leaves, they may be difficult to find at first. This requires us to be good at observation at ordinary times. Once found, we should immediately flick off the insects and do our best to do preventive work.

This type of insect usually appears in late May. Once it is found, if there are a lot of insects, after dealing with the infested leaves, you should also deal with other uninfested locations. If there are relatively few insects, be sure to remove them all.