Cotton root rot of okra, also known as Texas root rot, ozonium root rot, or Phymatotrichum root rot, is a nasty fungal disease that attacks at least 2,000 species of broadleaf plants, including peanuts, alfalfa, cotton, and okra. The fungus that causes Texas root rot in also infects fruit, nut, and shade trees, as well as many ornamental shrubs. The disease, which favors highly alkaline soils and hot summers, is limited to the Southwestern United States. Read on to learn what you can do about okra with Texas root rot.
Symptoms of Cotton Root Rot of Okra
Symptoms of Texas root rot in okra generally appear during summer and early autumn when soil temperatures have reached at least 82 F. (28 C.).
The leaves of a plant infected with cotton root rot of okra turn brown and dry, but usually don’t drop from the plant. When the wilted plant is pulled, the taproot will show severe rot and may be covered by a fuzzy, beige mold.
If conditions are moist, circular spore mats consisting of a moldy, snow-white growth may appear on the soil near dead plants. The mats, which range from 2 to 18 inches (5-45.5 cm.) in diameter, generally darken in color and dissipate in a few days.
Initially, cotton root rot of okra generally affects only a few plants, but diseased areas grow in subsequent years because the pathogen is transmitted through the soil.
Okra Cotton Root Rot Control
Okra cotton root rot control is difficult because the fungus lives in the soil indefinitely. However, the following tips may help you manage the disease and keep it in check:
Try planting oats, wheat, or another cereal crop in fall, then plow the crop under before planting okra in spring. Grass crops may help delay infection by increasing the activity of microorganisms that inhibit growth of the fungus.
Plant okra and other plants as early in the season as possible. By doing so, you may be able to harvest before the fungus becomes active. If you plant seeds, choose fast-maturing varieties.
Practice crop rotation and avoid planting susceptible plants in the affected area for at least three or four years. Instead, plant non-susceptible plants such as corn and sorghum. You can also plant a barrier of disease-resistant plants around the infected area.
Replace diseased ornamental plants with disease-resistant species.
Plow the soil deeply and thoroughly immediately after harvest.