Demystifying fairy rings in golf course putting greens

Transcription

1 Demystifying fairy rings in golf course putting greens Lane Tredway and Lee Miller Department of Plant Pathology North Carolina State University

2 Fairy ring is a destructive prolem in putting greens.

3 A variety of asidiomycete fungi can cause fairy ring.

4 What are the mechanisms of pathogenicity?

5 What are the mechanisms of pathogenicity?

6 What are the mechanisms of pathogenicity?

7 What are the mechanisms of pathogenicity?

8 Fungicides Laeled for Fairy Ring Control azoxystroin (Heritage) flutolanil (ProStar) metconazole (Tourney) polyoxin D (Endorse) pyraclostroin (Insignia) triadimefon (Bayleton)

9 Research green at Lake Wheeler Turfgrass Field Laoratory

10 Prevention of fairy ring caused y Vascellum pratense in creeping entgrass (July 11, 2006) Fairy Ring Severity (0 to 9) e Bayleton (2 oz) Lynx (2 fl oz) ProStar (2.2 oz) Insignia (0.9 oz) No Fungicide cde ac -e a-d w/ Revolution w/o Revolution e e a -e a All treatments applied twice in March and April Treatments were watered in immediately with 0.25 of irrigation Revolution applied at 6 fl oz/m

11 Fairy Ring Project Ojectives 1. Develop procedures for isolation and identification of fairy ring fungi from turfgrasses 2. Determine the distriution of fairy ring pathogens in golf course putting greens in the southeast US 3. Develop specific and effective recommendations for fairy ring prevention using fungicides

12 Isolation and Identification of Fairy Ring Fungi

13 Isolation and Identification of Fairy Ring Fungi

14 Isolation and Identification of Fairy Ring Fungi

15 Isolation and Identification of Fairy Ring Fungi

16 Isolation and Identification of Fairy Ring Fungi

17 Isolation and Identification of Fairy Ring Fungi

18 Isolation and Identification of Fairy Ring Fungi

19 Developing Effective Fungicide Programs application timing product selection post-application irrigation soil surfactants

20 Rate and Timing of DMIs for Fairy Ring Prevention Fungicide / Rate Bayleton - 1 oz/1000 ft 2 Bayleton - 2 oz/1000 ft 2 Lynx - 1 fl oz/1000 ft 2 Lynx - 2 fl oz/1000 ft 2 Soil temperature at initiation (5-day average) 50 F 55 F 60 F 65 F 70 F 75 F USGA putting green estalished in 2004 with A-1 creeping entgrass all treatments watered-in immediately with 0.25 of irrigation Cascade soil surfactant (8 fl oz/1000 ft 2 ) applied on 3/20, 5/2, and 7/25

21 Prevention of fairy ring caused y Vascellum pratense in A-1 creeping entgrass, 2007 Fairy Ring Severity (0 to 9) Bayleton (1 oz/m) Bayleton (2 oz/m) Lynx (1 fl oz/m) Lynx (2 fl oz/m) Untreated a a a a c c c 23-Jun 18-Jul 10-Aug **Data is averaged across all application timings

22 Prevention of fairy ring caused y Vascellum pratense in A-1 creeping entgrass, 2007 Fairy Ring Severity (0 to 9) A: 50 F B: 55 F C: 60 F D: 65 F E: 70 F F: 75 F a a a a c c c c 23-Jun 4-Jul 10-Aug **Data is averaged across all fungicides and rates

23 Bayleton, D, 2 oz Lynx, D, 1 fl oz

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25 June 22, 2007 Bayleton, D, 1 oz Untreated

26 Prevention of fairy ring caused y Vascellum pratense in A-1 creeping entgrass, 2008 Fairy Ring Severity (0-9) A: 50 F B: 55 F C: 60 F D: 65 F E: 70 F F: 75 F 0 June 23 July 7 Aug 4

27 Prevention of fairy ring caused y Vascellum pratense in A-1 creeping entgrass, Bayleton (1 fl oz) Lynx (1 fl oz) Untreated Bayleton (2 fl oz) Lynx (2 fl oz) Fairy Ring Severity (0-9) June 23 July 7 Aug 4

28 Fairy ring prevention in ermudagrass greens, 2008 Fairy Ring Severity (0 to 9) a a

29 Fairy ring prevention in creeping entgrass, 2008 Fairy Ring Severity (0 to 9) cd cd d d cd a c a

30 Refining Fungicide Recommendations How do wetting agents influence performance of preventative applications? Does post-application irrigation improve preventative control? If so, does irrigation need to e applied immediately?

31 Refining Fungicide Recommendations Irrigation immediately after application 10 hours after applicaton Fungicide Bayleton (1 oz) Triton (0.25 oz) None Wetting Agent Revolution (6 fl oz) None creeping entgrass putting green split-split-plot, randomized complete lock applied in late March and late April fairy ring symptoms assessed throughout summer

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34 Impact of Revolution on Fairy Ring Control a Fairy Ring Severity (0 to 9) a

35 Phytotoxicity - Tank-mixing Revolution (6 oz/1000 sq ft), 2008 Phytotoxicity (0-9) a Bayleton 4SC (2 oz/1000 sq ft) Triton 70WG (0.25 oz/1000 sq ft) Untreated 0 c c c + Revolution - Revolution c Treatments applied on March 28 & April 25 Data collected on May 27 Bars with same letter are not significantly different according to LSD ( =0.05).

36 Conclusions and Recommendations the most common fairy ring pathogens in sand-ased putting greens are the puffall species Lycoperdon pusilum and Vascellum pratense DMI fungicides provide effective prevention of fairy ring when soil temperatures are etween 55 F and 70 F tank-mixing with soil surfactant may slightly reduce efficacy of DMI fungicides and increase the potential for phytotoxicity applications should e watered-in within 12 hours after application for est results

37 Acknowledgments Turf Pathology Students and Staff Lee Miller Mike Soika Lee Butler Funding NC State Turfgrass Center (CENTERE) Lee Miller Bayer Environmental Science Golf Course Superintendents Association of America Carolinas Golf Course Superintendents Association Mike Soika