FRAC CAA Working GROUP 1 st Meeting Sheraton Airport Hotel Frankfurt 27th October 2005

1. FRAC CAA Working GROUP 1st Meeting Sheraton Airport Hotel Frankfurt 27th October 2005 hosting company: BASF

2. Meeting 27th October 2005 Sheraton Airport Hotel, Frankfurt, Germany Participants: BASF: Randall Gold, Kristin Klappach, Gerd Stammler BCS: Klaus Eckstein, Karl-Heinz Kuck, Marie-Pascale Latorse Kumiai: Masuro Yokoyama Syngenta: Ulrich Gisi, Yasuhiro Hirai, Fritz Huggenberger Draft

3. Agenda • Formation of the New FRAC «Carboxylic Acid Amide • (CAA) Working Group» • Election of a chairperson • Agreement on agenda • Sensitivity monitoring results 2005 • Analysis of strategy trials • Discussion on future CAA recommendations • Future publication at the FRAC homepage • Other items / next meeting • KH Kuck •  Draft

4. Introduction New FRAC Working Group Mode of action: Inhibition of phospholipid biosynthesis and interference with cell wall deposition (proposed) Cross resistance: Although not always obvious for some isolates, there is positive cross resistance for the vast majority of isolates. Draft

5. Inheritance studies • Sexual crosses between S and R isolates lead to a co-segregation of • resistance to DMM, IVC, mandipropamid and benthiavalicarb but not • to the phenylamide mefenoxam (independent marker). • Resistance is inherited in a recessive manner probably based on • more than one gene. •  entire F1 generation of crosses between S and R isolates is • sensitive to CAAs and only in the F2 generation the CAA • resistance becomes again visible. • suited to explain some characteristics of the CAA resistance especially in view of the limited spread and propagation of resistant isolates in field populations Draft

6. Plasmopara viticola: Resistance status Market introduction dimethomorph 1994 iprovalicarb 1998 Under development: benthiavalicarb mandipropamid • long term monitoring experience available • increasing intensity last several years Draft

7. Plasmopara viticola: Resistance status France Gers (Armagnac) resistant isolates consistantly found Bordeaux - resistant isolates detected Loire less frequently Champagne - large fluctuations Rhone valley - no stable trend for increase etc. or decrease Germany all major vine growing same as in France except Gers areas Draft

8. Plasmopara viticola: Resistance status • Systematic monitoring in • Italy, Spain and Portugal and (later on) Switzerland. • Few resistant strains found in the nineties in Italy and • Portugal • Since 2000, all strains collected from commercial fields • in Italy, Switzerland, Spain and Portugal were fully • sensitive. Draft

9. Phytophthora infestans • Monitoring studies by all companies covering • all major potato and tomato growing areas • all years since 1994 •  resistant isolates never detected Draft

10. Other Oomycete Pathogens No validated reports on field resistance available Draft

11. Conclusions Plasmopara viticola • Resistance risk is moderate and can be managed if • appropriate strategies are implemented • Supporting facts: • no resistance related complaints as long as multi-site mixtures • have been used • resistance frequency is mostly fluctuating with no clear • progression over years and regions • resistance genes are inherited in a recessive manner Draft

12. Use Recommendations Plasmopara viticola • Resistance risk in Plasmopara viticola to CAA fungicides is • estimated as moderate • Apply a maximum of 4 CAA sprays during one crop cycle not • exceeding 1/3 of all downy mildew treatments • Apply CAA fungicides always in mixture with effective partners • such as multi-sites or other non cross resistant fungicides • An effective partner for a CAA fungicide is defined as providing • satisfactory disease control when used alone at the same rate as • used in the mixture Draft

13. CAA Use Recommendations Other Oomycete pathogens • Refer to use guidelines of • manufacturers Draft

14. Next CAA meeting: mid December 2006

18. Thank you for your kind attention !