The Disease Triangle

In order for disease to occur three conditions are necessary (1) A susceptible host (2) An active pathogen (3) Favorable environment If any of the three conditions are missing, disease will not develop.

Fungicide Resistance:

Fungicide resistance is the naturally occurring inheritable adjustment in the ability of individuals in a population to survive a plant-protection product treatment that would normally offer effective control.

FRAC: Fungicide Resistance Action

This committee is an organization that works to prolong the effectiveness of fungicides that are liable to encounter resistance problems and to limit crop loss should resistance occur.

Visit their site to learn more: www.frac.info

Best Practices recommended to avoid the Resistance of Fungicides:

Diseases Progress in 4 Stages:

1. Infection: Disease pathogen enters the plant.

2. Incubation: Pathogen begins to live off the host plant. This pathogen inhibits its host without producing visible symptoms.

3. Symptom Development: Interaction between pathogen & susceptible host. Some visible examples: Lesions, Wilting, Leaf Spots, etc.

4. Inoculum Production: Stage when pathogen reproduces & spreads for self-preservation.

Some Steps to consider managing Turf Diseases effectively are as follows:

• Monitoring: Identify disease and percentage of coverage. Become familiar with its life cycle.

• Identification: Look for physical evidence of a problem such as:

1. Injury

2. Changes in site conditions

3. Soil compaction

4. Construction injury

5. Lawn Mower injury

6. Diseases

Methods of Control:

1. Cultural Controls:

• Proper sanitation

• Proper fertilization

• Irrigation (Early AM is recommended)

• Proper site selection

• Proper mowing height (3” or higher is recommended)

2. Biological Controls:

• Biological Agents: Milky Spore, Nematodes.

• Trichoderma Harzianus: Naturally occurring fungi that is used in the suppression of root diseases.

• Streptomyces Griseovirdis: Naturally occurring soil bacteria. The microbe deprives pathogenic fungi of living space & nourishment.

• Resistant Grass Seed Varieties: Bred specifically to resist certain diseases.

3. Pesticide Controls:

• Proper use of fungicides

• Least toxic solution first

• Preventative

• Curative

• DMI & Strobilurin Classes

• Use of resistant varieties.

• Permanent disease monitoring.

• Calibration of application equipment.

• Use of a sound fungicide rotation program. Select products from different pesticide classes to avoid resistance.

• Do not shorten the application periods of fungicides.

• Respect the residual times of each one.

• Do not use fungicides that are not labeled or registered for the crops on which they will be applied.

• Read and follow ALL information on the pesticide label of the product of choice for that particular fungicide application.

Doug Cherry is a graduate of SUNY Cobleskill with a Bachelor of Technology in Plant Sciences. Doug has been serving his customers providing situational knowledge & insights for 28 years in the Green Industry. He is a Sales Representative for SynaTek Solutions working in the Lawn & Landscape division. Doug has a true passion for Horticulture along with a focused dedication to helping customers solve problems achieving positive outcomes as an endresult. This consultative approach creates value that leads to the growth & overall success of their business. You can reach Doug at dcherry@synateksolutions.com.