The fungus, Rhizoctonia solani , however, is the predominant organism. The fungus attacks young plants before and after emergence, and continues to attack surviving plants to a lesser extent during the growing season.
Diseased plants have lesions on their roots immediately below the ground line.
These lesions enlarge to kill seedlings and weaken older plants. Flax plants with roots injured by Rhizoctonia solani appear to be considerably more susceptible to damage by cold weather and root rotting fungi. Use recommended seed and soil treatment fungicides. This is probably the most important disease of flax in Texas. Lesions develop first on the cotyledons and later on the lower leaves of the seedling.