Highlights from the Fungicide Resistance Tailgate Meeting
- Populations of powdery mildew (PM) become resistant to a fungicide from repeated exposure to the same material over time
- Resistance is often attributable to differences in a single gene between members of the population.
- Once exposure to that particular fungicide ends, the diversity of the PM population drifts back to being primarily susceptible.
- Different types of fungicides (FRAC groups) work by interfering with or inhibiting a particular biological pathway.
- PM populations resistant to FRAC 11 fungicides (strobulurins) are wide spread on the West Coast.
- There is a robust molecular genetic technique to monitor resistance.
- There might be potential to rejuvenate FRAC 11 fungicides (strobulurins).
- Molecular tools could develop a fungicide stewardship program.
- Populations of PM resistant to FRAC 11 fungicides can be identified by diagnostic labs now using molecular genetic methods.
- PM populations resistant to FRAC 3 (DMI) fungicides are widespread.
- There is a molecular genetic tool that can detect resistant population.
- This tool is not quite ready to be released to diagnostic clinics/laboratories.
- Control failures and resistance to FRAC groups 7 and 13 and have been reported.
- Further investigation is required.
- How far and how fast does fungicide resistant PM move? We don’t know, but it is being investigated.
Additional Resources
