When discussing resistance management, there is a notion among turf pros that the repeated use of a pesticide causes the pest to mutate and become resistant to the pesticide being applied.

Resistance is not the result of pests mutating and becoming “resistant” from exposure to a particular pesticide. Real resistance means that a small part of the pest population has an inherited trait that makes it unaffected by a specific chemical mode of action. Resistant strains of a pest occur naturally at a very low frequency. As this resistant population reproduces and passes these inheritable traits from one generation to the next, the pesticide will no longer provide control as the resistant, or “survivor”, population becomes the majority. Repeated fungicide use increases the frequency of resistant individuals as they reproduce. The genetically strong individuals survive.

To manage pests successfully, minimize resistant pest populations and maintain product efficacy, superintendents need to responsibly steward chemistries.

Make the most of your resistance management program by incorporating the following strategies:

• Use labeled rates and application intervals
• Focus on good spray coverage
• Limit the number of strobilurin applications
• Rotate different modes of action in your spray program
• Adhere to the label and Fungicide Resistance Action Committee (FRAC) recommendations

Stay tuned for an article by Steve Larson on the topic of resistance management in the May issue of Golf Course Management magazine…