Epidemic disease and its control

Symptoms: needles occur all the year round in Taiwan, but in the rainy season, the disease is the most serious when it is overwatered or poorly ventilated, especially the seedlings just out of the bottle are the most vulnerable.

The symptoms of various Cymbidium infections are different. Cartland, Phalaenopsis, Dendrobium, Oncidium, Cymbidium and other susceptible parts produce brown spots, which expand rapidly in high temperature and humidity, and finally show dark brown, and the leaves and stems rot to the death of the whole plant. The roots will also be damaged and rot, extending to the pseudobulm or aboveground. If Cymbidium (Cymbidium, East Aram) and Cymbidium are susceptible to disease, yellowing does not cause soft rot.

Prevention and control methods:

1. Avoid too much watering or too high air humidity, improve ventilation and adequate light.

two。 Avoid partial use of nitrogen fertilizer to reduce plant overgrowth and weakness.

3. Remove the diseased plant immediately or remove the diseased tissue at the initial stage of the disease. The uninfected part and its plant materials and pots were soaked in copper sulfate 300 times solution or 75% chlorothalonil wettable powder 600 times solution for 10 minutes. Spray the same medicine the next day to prevent it.

4. The wound removed by the diseased plant should be smeared with 70 mancozeb wettable powder and placed in a dry place without watering within 1 week, which can curb the spread of the disease.

5. Knives for removing diseased plants should be sterilized to avoid infection.

6. Therapeutic agents: Prike (chloramphenicol hydrochloride) 1000 times solution or 50% Phytophthora 500 times solution, seedlings sprayed once a week, adult plants sprayed once a month.

7. At ordinary times, use 1RV 200 Bordeaux solution or 70% forest manganese and zinc 500 times solution for top prevention, and spray it regularly every 2 weeks. The rainy season is changed to once a week. (Xue Congxian)