Rhizoctonia Root Rot


Rhizoctonia is a serious problem in sugarbeet causing root and crown rot. While some fungicides are available to combat the disease, advances in plant breeding continue to provide the best chance of success against Rhizoctonia.

The fungus responsible for Rhizoctonia, Rhizoctonia solani, is common in sugarbeet in all countries where the crop is grown and climate, soil type and crop rotations make conditions favorable for its development.

Progress in the development of better genetic tolerance to Rhizoctonia has been slow compared to other sugarbeet diseases like Rhizomania due to the complexity of its multi-gene structures and the difficulty in managing these structures with genetic markers. In addition, the source of the Rhizoctonia-resistant gene structure goes back to wild relatives of the sugarbeet. This means introducing resistant genetics has an adverse effect on many of the desireable characteristics of cultivated sugarbeets. To put it simply, Rhizoctonia-resistant varieties have yet to produce the same consistent yield and quality as conventional seed varieties.

But there’s hope. Great strides continue to be made, thanks in part to research done in the United States. Seedex, Inc. is very proud of its key contributions to the development of Rhizomania-Rhizoctonia tolerant hybrids. These commercial varieties provide industry-leading solutions for most environments plagued with Rhizoctonia.

Marc Meulemans
Plant Breeder
Seedex, Inc.


Rhizoctonia Root Rot
1. Introduction, Damping Off, and Epidemiology
2. Symptoms and Economic Importance
3. Disease Control and Dual Resistant Varieties
4. Summary

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