Diseases

Rhizoctonia root rot — sugar beet

Beta vulgaris Sugar Beet Group

An economically significant disease of the sugar beet root system caused by the fungi Rhizoctonia solani and Rhizoctonia violacea. It manifests in the second half of the growing season as root rot and wilting of the aerial parts of the plant.

In the reference 88 varieties crop Sugar beet, where this is mentioned in the description.

The causative agent of the disease is the soil-borne fungus Rhizoctonia solani, as well as Rhizoctonia violacea, which is characterized by the Helicobasidium purpureum stage, causing so-called violet root rot. Symptoms of the infection usually become visible after row closure during warm weather and high humidity. In diseased plants, leaves yellow and wilt, often remaining attached to the crown as a brown rosette, while a black or brown dry rot forms on the surface and inside the root crops.

With violet root rot, gray depressed spots are observed on the root crops, covered with dark purple mycelium, on which red-violet sclerotia subsequently develop. The resistance of sugar beet to the pathogen is polygenic in nature and is defined as tolerance. No specific R-genes are identified in breeding programs, although modern DNA marker methods are used to evaluate breeding material.

General information about the subject — on the page Rhizoctonia.

Sources8

Varieties of Sugar beet mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.