Disease of Lanhui

At present, almost all of the orchids cultivated are original species, and they are supposed to have innate strong disease resistance. However, due to being planted in pots for a long time, its wild nature has long been lost due to different environments or improper management.

Lan Hui does not immediately show obvious symptoms after the pathogen enters the plant, so for a layman, it is difficult to detect that Ailan is sick before Lan Hui is abnormal.

In addition, because the symptoms caused by the same pathogen will be different in color and shape due to different time and place, it is not easy for laymen to judge whether the plant is sick or not. As long as Lan Hui has been ill once, there will be endless problems after that, so we must pay more attention to it so as not to let the original disease invade the orchid plant.

When buying Lanhui, you should first carefully examine its roots to see if it suffers from some kind of disease.

Tools that have come into contact with Lanhui should be thoroughly disinfected, and old plant materials should be destroyed and discarded so as to cut off the opportunity for pathogens to enter people from the roots.

Explain it with the following list of the most common victims and the types of diseases.

Budding disease

From April to September during the bud growth period, if the roots of the new buds suddenly become tea-colored and rot when the leaf sheath is healthy, this is due to soft rot, and the way to prevent it is not to let the water stay on the buds.

The buds stop growing when they are young, and black spots appear, which is caused by anthrax. The prevention method is to spray organic sulfur fungicide (Dasheng) twice a month.

Diseases of leaves, roots and petals

Anthrax: after the temperature rises, irregular brown spots appear in the leaves, and the area gradually expands, or swirling brown patterns show that anthrax has been obtained, and the prevention method is the same as mentioned above.

Leaf blight: the leaf tip suddenly turns brown and withered, or the base or sheath of the leaf changes color, and there are black spots around it, indicating leaf blight. When there is a root disorder, it is easy to get the disease. The prevention method is the same as above.

Atrophy: when there are some white spots on the leaves, or yellow stripes, soil gangrenous spots, indicating suffering from atrophy. This disease cannot be prevented by medicine, and once the disease comes again, it should be quarantined immediately. As the disease is easily transmitted by water, the watering method of soaking the pot in a bucket or the management of putting it under the scaffolding should be suspended immediately to prevent the disease from spreading to other plants.

Soft rot: at high temperature, the leaf base suddenly turns yellowish brown, and the bulbs also rot, indicating that you suffer from soft rot. The way to prevent it is to maintain good ventilation and drainage, and do not let the water stay on the new buds.

White silk disease: at high temperature, white filaments appear near the leaf root or on the bulb, and produce many brown granules. This is a disease called white silk disease, which in a twinkling of an eye can wither the whole orchid and cause white hyphae around the roots. as it has no medicine to treat, as soon as the diseased plant appears, it should be immediately discarded or planted with new plant materials to isolate it. The preventive method is to keep the bowl clean as far as possible, and do not let the bowl come into contact with the ground.

Gray mildew: when blooming, the petals appear watery, discoloration, but also the growth of mold, which indicates gray mold. The way to prevent it is to keep the petals out of the water, spray them with 2,000 times the diluent of melyde when the buds are still very small, and don't talk about the high temperature and humidity in the room. (Zhang Fengrong)