Testing biological controls for a turfgrass disease
Turfgrass is a commodity found on sod farms and in golf courses, parks, and athletic fields. IPM for turfgrass has been a part of the New York IPM Program effort since 1986. Several strains of beneficial bacteria and fungi were tested in 1996 for their ability to manage Pythium root rot, a turfgrass disease, and for their compatibility with fungicides that are currently used to treat this disease.
While several of the biological control agents were found to have great potential for managing Pythium root rot, they were also found to be, in large part, negatively affected by the fungicides. The opposite effect was also seen: populations of some of the biological controls were stimulated by some of the fungicides rather than reduced by them.
Whether the fungicides that reduce populations of the biological control agents will cause reductions in their effectiveness against diseases and whether the opposite is true for those fungicides that stimulate the biologicals are questions to be determined by further testing this year.
Such data are of great interest to New York's turfgrass managers. Cornell plant pathologist Eric B. Nelson says that "Because of the negative side effects accompanying increased fungicide use, turfgrass managers are realizing that biological and combined biological/chemical methods of disease control are becoming essential to turfgrass management."