Diseases

Rhizoctonia Root Rot — Fodder Beet

Beta vulgaris Fodder Beet Group

A fungal disease of fodder beet caused by Rhizoctonia solani, manifesting as seedling damping-off or the formation of localized root rot in mature plants.

In the reference 7 varieties crop Mangelwurzel, where this is mentioned in the description.

The causal agent of Rhizoctonia root rot in fodder beet is the fungus Rhizoctonia solani (teleomorph Thanatephorus cucumeris). The most pathogenic groups for this crop are recognized as anastomosis groups AG 2-2 (subgroups AG 2-2 IIIB and AG 2-2 IV), with groups AG 4 and AG 5 also potentially involved in the infection process.

At the seedling stage, the disease manifests as damping-off, where the hypocotyl softens, becomes covered with dark spots, and collapses. In mature plants, after row closure, brown or black rot lesions appear on the taproots, accompanied by leaf wilting and the formation of grayish mycelial cracks.

Complete genetic resistance to the pathogen is absent in fodder beet varieties. Breeding efforts are underway to identify tolerance and study the NBS-LRR gene families responsible for pathogen recognition; however, specific resistance markers are not yet listed in commercial catalogs.

General information about the subject — on the page Rhizoctonia.

Sources8

Varieties of Mangelwurzel 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.