Black root rot is a common disease in North Carolina, a top strawberry producing region, and much of the southeastern region of the United States, having been shown to reduce yields by 20 to 40%. This is the main reason growers fumigate their fields in this region. Pre-planting fumigation may suppress the disease during the year of planting, but typically it does not offer any lasting control and cultivars resistant to black root rot are not currently available. Black root rot has been a challenge for strawberry growers for at least a century, and probably longer. Black root rot of strawberry is recorded to have been prevalent in Massachusetts, Michigan, and New York in the years 1902 and 1908. In 1920 a Rhizoctonia species was first assigned as the causal pathogen responsible for “dying out” of strawberry beds in western Washington. By 1988, R. fragariae was isolated from more than 70% of plants from commercial strawberry fields in Connecticut in cultivation for more than one year.
