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Rhizoctonia is a common seed-and soil-borne fungus with significant saprophytic characteristics (feeds on dead organic matter). Rhizoctonia causes “damping-off” in cultivated fields, ornamental plants, and turf grass. The pathogen overwinters on plant residue and soil.

Several types of rhizoctonia attack plants and are known by their non-host specialization; in other words, they can affect many types of plants. One such specie is rhizoctonia solani, which is the causal agent of black scurf of potatoes, violet root rot in carrots, bare patch of cereals, root rot of sugar beet, belly rot of cucumber, and sheath blight of rice.

Rhizoctonia favors high humidity conditions and can develop in a broad-spectrum of temperatures: 10-32c. Rhizoctonia tends to occur within the short time frame adjacent to planting; the fungi attacks plants at the soil line. Easy to spot symptoms of Rhizoctonia are “damping off” and reduced seed germination. Infected seedlings exhibit red to brown lesions primarily at the stem base. Red-brown to black lesions will form on roots. With time, infected seedlings will wilt, while older, more mature plants will exhibit an increased tolerance to the disease.