Control Methods for Clivia Root and Crown Rot and Edible Mushroom Diseases

Symptoms

Clivia root and crown rot is distributed throughout the country. Under continuous high-temperature conditions, the leaves and flowers develop water-soaked brown large-area rot, and the diseased parts are covered with a hard-to-notice white mold layer; when dry, the diseased parts turn grayish-brown. The flower stalks and leaf petioles are also affected.

The pathogen is caused by infection with Phytophthora sp.

Occurrence Pattern

When air humidity is high and the temperature is around 20°C, the disease is most likely to occur. Winter greenhouse warming and moisture retention, as well as continuous watering in spring as temperatures rise, lead to severe disease incidence.

Control Methods

1. Apply formulated fertilization to improve plant stress resistance.

2. Water on sunny days, and ventilate in a timely manner after watering in the greenhouse to remove moisture.

3. In the early stage of the disease, the following application methods can be chosen: commonly used spray agents include 25% metalaxyl wettable powder at 600 times dilution, 40% phosethyl-Al wettable powder at 250 times dilution; 58% metalaxyl mancozeb wettable powder at 500 times dilution, 40% metalaxyl copper wettable powder at 700 times dilution, 64% oxadixyl mancozeb wettable powder at 500 times dilution, or 77.2% propanocarb aqueous solution at 800 times dilution. When cultivating in greenhouses or plastic tunnels, smoke agents can be applied.