Control methods of common diseases and insect pests of Dendrobium

1. Diseases:

(1) soft rot: also known as bacterial brown spot, mostly infected from the rhizome, can also occur on the leaves, the primary water stains dark green spots, gradually expanded into brown softening rot, and there are secretions from the rotten parts, accompanied by bad smell. Germs can be spread by watering. High temperature and humidity are beneficial to the occurrence of disease. once susceptible plants are found, they should be isolated and destroyed and controlled with agricultural streptomycin, Bordeaux solution or methyl parathion.

(2) Black spot: it is the main disease of Dendrobium, which occurs in the leaves. At the beginning, it was a small brown spot, and then it was enlarged into a nearly round spot with necrosis in the center and a grayish brown spot with a diameter of 0.5~1.0cm. When the disease is serious, the disease spot is connected into a piece, causing the leaves to yellowing and falling off.

2. Insect pests:

The main results are as follows: (1) aphids: the young leaves and buds of Dendrobium are mainly harmed by piercing and sucking mouthparts into the epidermis to absorb plant sap nutrients, causing leaves and new buds to deform and wilt, and disease invasion at the same time. Control methods: strengthen ventilation, improve the cultivation environment, combined with drug spraying, you can use 20% fenvalerate 1500 times liquid, 40% omethoate 1000 times solution spray control.

(2) scale insect: a common pest in Dendrobium cultivation, mainly parasitic on the back of the leaf or in the leaf sheath. It occurs in an environment with low air humidity and poor ventilation. At the initial stage of damage, the leaves yellowed and affected photosynthesis. in severe cases, the plants died or could not grow and bloom normally. In addition to strengthening ventilation, a small amount of it can be removed with a soft brush. For drug control, 50% malathion or 25% Jiaozhujing 800 / 1000 times was sprayed once a week for 3 consecutive 4 times.

(3) snails and slugs are more common in long-term wet or rainy seasons. Climbing out of the new buds or root tips that bite Dendrobium at night, causing serious hindrance to growth. It can remove weeds and moss on the ground; when a small amount occurs, it can be killed manually at night or by spreading quicklime on the ground and wall corners; when it occurs in a large area, it can be treated with 80% snail or 90% trichlorfon drugs.