Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

GCSAA Research Update


Published on

GCSAA Frank Wong Research update

Published in: Technology, Education
  • Be the first to comment

GCSAA Research Update

  1. 1. Brown Ring Patch Management <ul><li>Dr. Frank P. Wong & Chi-Min Chen </li></ul><ul><ul><li>Department of Plant Pathology & Microbiology </li></ul></ul><ul><ul><li>University of California, Riverside </li></ul></ul><ul><li>Dr. Larry Stowell </li></ul><ul><ul><li>PACE Turf Research Insitute </li></ul></ul><ul><ul><li>San Diego, CA </li></ul></ul><ul><li>This research was supported by a 2008-2009 GCSAA Chapter Cooperative Grant from the GCSAA Environmental Institute for Golf, California State GCSA, and the Southern & Northern CA, San Diego, High Lo Desert & Sierra Nevada GCSAs </li></ul>
  2. 2. 2008-2009 GCSAA Funded Research <ul><li>Awarded 2 year grant by GCSAA & EIFG to study the biology & management of the disease </li></ul><ul><ul><li>Contributions from: California State GCSA, and Southern & Northern CA, San Diego, High Lo Desert & Sierra Nevada GCSAs </li></ul></ul><ul><li>Population Biology </li></ul><ul><li>Fungicide Effects </li></ul><ul><li>Cultural Practice Effects </li></ul>
  3. 3. Waitea Patch aka Brown Ring Patch <ul><li>A “new” Rhizoctonia disease of annual & rough bluegrass, and creeping bentgrass in the U.S. </li></ul><ul><li>Superficially looks like Yellow Patch </li></ul><ul><li>First came to attention in 2003 based on reports from Spokane area golf courses </li></ul><ul><li>Determined to be a Rhizoctonia species </li></ul><ul><li>Fairly widespread in the western and northern U.S. by 2006 </li></ul>
  4. 4. Brown Ring Patch Symptoms on an Annual Bluegrass Green Photo by Pat Gradoville, Palos Verdes Golf Club
  5. 5. Rings start as small thin yellow circles a few inches in diameter that can expand to a foot or more in diameter. Rings can become orangish to brown and sunken if not treated. Rings can often merge together. Photo by Kent Davidson
  6. 6. Left untreated or treated too late, sunken dead areas may develop and take a long time to recover from Photo by Mike Wolpoff, Sea Cliff Country Club
  7. 7. Symptoms are very similar to Yellow Patch (R. cerealis), but Yellow Patch tends to occur at maximum daytime temperature below 65 deg F
  8. 8. Patches often have a greenish color that develops behind the yellow ring. These areas tend to be soft and sunken.
  9. 9. The mechanism of the greening is unknown; it may be a result of nitrogen being released from broken down thatch or increased microbial activity inside the affected areas
  10. 10. The pathogen, Waitea circinata var. circinata (stained red in this photo), colonizes leaves, sheaths and crowns.
  11. 11. The fungus also can colonize the thatch, upper root zone and soil
  12. 12. The fungus produces abundant mycelia in high humidity situations; this is called the ‘Don King’ appearance of the fungus. Photo by Larry Stowell
  13. 13. The pathogen degrades thatch, resulting in sunken rings on greens Photo by Mike Wolpoff, Sea Cliff Country Club
  14. 14. Rings expand a few inches in size a week – photos are taken 1 week apart from each other. This suggests that the disease more dynamic than previously thought.
  15. 15. The brown ring patch is rare on creeping bentgrass in the U.S. Rings that develop on creeping bentgrass tend to have a brown color. Photos taken from the Color Atlas Of Turfgrass Diseases by James B. Beard & Toshhikazu Tani (2002)
  16. 16. Brown Ring Patch on rough bluegrass also appears more reddish to brown in color
  17. 17. Distribution of W. circinata var circinata in the U.S.
  18. 18. Brown Ring Patch & Other Rhizoctonia Diseases <ul><li>Brown ring patch is a Rhizoctonia disease </li></ul><ul><li>Waitea circinata var. circinata is closely related to high temperature brown patch (leaf & sheath spot) pathogens Rhizoctonia oryzae and Rhizoctonia zeae </li></ul><ul><li>But – there is no ‘Rhizoctonia name’ for the pathogen that causes brown ring patch, so we have to use Waitea circinata var. circinata </li></ul>
  19. 19. Disease Teleomorph Name (Sexual State) Anamorph name (Asexual State) Optimal Temp. Range (Max. Daytime Temps.) Typical hosts Yellow Patch Ceratobasidium cereale Rhizoctonia cerealis 50-65ºF Cool & warm season species Brown Patch of Cool Season Turf Thanatephorus cucumeris Rhizoctonia solani 77-90ºF All cool season species Brown Patch of Warm Season Turf (Large Patch) Thanatephorus cucumeris Rhizoctonia solani 60-77ºF All warm season species Leaf and Sheath Spot (High Temperature Brown Patch) Waitea circinata var oryzae Rhizoctonia oryzae 83-97ºF Cool & warm season species Waitea circinata var zeae Rhizoctonia zeae 83-97ºF Brown Ring Patch (Waitea Patch) Waitea circinata var circinata none 77-86ºF Annual Bluegrass, Creeping Bentgrass, Rough Bluegrass
  20. 20. Brown Ring Patch Trials at Torrey Pines Golf Course 2008 (North Course)
  21. 21. 2008 Research at Torrey Pines <ul><li>Field experiments were conducted in the Spring on the North Course </li></ul><ul><li>Greens were made available as the South Course was being prepared for the U.S. Open </li></ul><ul><li>Research was performed with North Course Superintendent Wayne Carpenter, and Jon Maddern and Mark Woodward, Directors of Golf for the City of San Diego </li></ul>
  22. 22. Research Objectives <ul><li>Examine the effects of nitrogen fertility and trinexapac-ethyl (Primo MAXX) on brown ring patch development </li></ul><ul><li>Evaluate fungicide applications for the curative control of the disease </li></ul>
  23. 23. Nitrogen & Trinexapac-ethyl <ul><li>Nitrogen </li></ul><ul><ul><li>Observed that diagnostic samples with brown ring patch were often nitrogen deficient </li></ul></ul><ul><ul><li>Traditionally, high nitrogen is associated with increased Rhizoctonia brown patch severity on greens </li></ul></ul><ul><ul><li>Effect on brown ring patch unknown </li></ul></ul>
  24. 24. Nitrogen & Trinexapac-ethyl <ul><li>Trinexapac-ethyl (Primo MAXX) </li></ul><ul><ul><li>Primo MAXX regulates plant cell elongation </li></ul></ul><ul><ul><li>Outbreaks reported to coincide with spring Primo MAXX applications </li></ul></ul><ul><ul><li>Unknown if the plant growth regulator effects of Primo MAXX increase disease severity for brown ring patch </li></ul></ul>
  25. 25. 2008 Trials at Torrey Pines GC <ul><li>Conducted on the North Course with Wayne Carpenter </li></ul><ul><li>Water soluble nitrogen applied on 8 Apr and 22 Apr (exp 1) and 3 & 17 May (exp 2) at the rate of 0.5 lb/1,000 sq ft (1 lb total) </li></ul><ul><ul><li>calcium nitrate 15-0-0 </li></ul></ul><ul><ul><li>ammonium sulfate 21-0-0 </li></ul></ul><ul><ul><li>urea 46-0-0 </li></ul></ul><ul><li>Trinexapac-ethyl (Primo MAXX) applied at 0.125 fl oz/1,000 sq ft in combination with nitrogen to some plots </li></ul>
  26. 26. 2008 Trials at Torrey Pines GC <ul><li>Disease severity assessed visually or by photographic analysis </li></ul><ul><li>Turf quality assessed by the use of a CM-1000 chlorophyll meter </li></ul><ul><li>Readings made weekly for 5 & 7 week periods </li></ul>
  27. 27. Digital disease analysis using Sigma Plot software and images taken with a Canon D70 camera
  28. 28. Nitrogen and Primo MAXX Effects <ul><li>Applications of 1 # nitrogen/1,000 sq ft resulted in a significant reduction in brown ring patch </li></ul><ul><li>No effect of source was observed in trials </li></ul><ul><li>Applications of Primo MAXX alone slightly increased disease severity on some rating dates </li></ul><ul><li>Primo MAXX plus nitrogen significantly reduced disease </li></ul>
  29. 29. Nitrogen effects on disease severity
  30. 30. Nitrogen & Primo MAXX effects
  31. 31. Nitrogen vs Nitrogen + Primo
  32. 33. water nitrate + Primo MAXX wk 1 ammonium + Primo MAXX urea + Primo MAXX wk 3 wk 5 water + Primo MAXX
  33. 34. Nitrogen and Primo MAXX Effects <ul><li>In both trials, color (chlorophyll) was increased by nitrogen application </li></ul><ul><li>No affect of source was observed at the rates used </li></ul><ul><li>Primo MAXX used alone, increased turf color </li></ul><ul><li>Primo MAXX used with nitrogen resulted in the overall highest turf color </li></ul>
  34. 37. Interactions with fungicides <ul><li>Experiment took place on Greens 2 and 6 </li></ul><ul><li>1 fl oz Heritage TL/1,000 sq ft applied to affected areas </li></ul><ul><ul><li>with 0.5 lb/ 1,000 sq ft calcium nitrate </li></ul></ul><ul><ul><li>with 0.5 lb calcium nitrate & 0.125 fl oz Primo MAXX/ 1,000 sq ft </li></ul></ul><ul><li>It was suspected that the low labeled rate of fungicide would not completely control disease, but the potential interactions between nitrogen and Primo MAXX was being demonstrated </li></ul>
  35. 38. Heritage Heritage + N Heritage + N + Primo MAXX wk 1 wk 2 wk 3 wk 4
  36. 39. Nitrogen, Primo & Heritage effects a a b b b b a Disease severity
  37. 40. Fungicide Trials <ul><li>Previous studies had shown variable curative activity of fungicides for control of disease </li></ul><ul><li>We suspected that DMI-fungicide tank mixes may be effective for brown ring patch control </li></ul><ul><li>Not much fungicide trial data had been available for this disease and more data was needed to make better management recommendations </li></ul>
  38. 41. Materials Under Trial Pt 1
  39. 42. Materials Under Trial Pt 2
  40. 43. Trial 1: Effects of DMIs and DMI mixtures on brown ring patch
  41. 45. C B A
  42. 46. B A C
  43. 47. B C A
  44. 48. B C A
  45. 49. B C A
  46. 50. Trial 2: Effects of Rhizoctonia fungicides on brown ring patch
  47. 51. A C B
  48. 52. D B C A
  49. 53. A B C
  50. 54. A C B
  51. 55. A C B
  52. 56. Trial 3: Effects of repeated QoI fungicide applications on brown ring patch
  53. 58. C B A
  54. 59. C B A
  55. 60. C B A
  56. 61. C A B
  57. 62. Summary <ul><li>Nitrogen effects </li></ul><ul><ul><li>Applications of 1 lb nitrogen/1,000 sq ft significantly reduced Waitea patch severity </li></ul></ul><ul><ul><li>No effect of nitrogen source was seen </li></ul></ul><ul><ul><li>nitrate = ammonium = urea </li></ul></ul><ul><li>Trinexapac-ethyl (Primo MAXX) effects </li></ul><ul><ul><li>No effect of Primo MAXX on disease severity </li></ul></ul><ul><ul><li>Primo MAXX applications increased turf quality (color) </li></ul></ul><ul><ul><li>Primo MAXX + nitrogen = highest turf quality </li></ul></ul>
  58. 63. Summary <ul><li>Nitrogen x Primo x Fungicide Interactions </li></ul><ul><ul><li>Fungicide (Heritage TL low rate) effectiveness was improved when applied with nitrogen and Primo MAXX </li></ul></ul><ul><ul><li>The effect of 0.5 lb calcium nitrate was not very pronounced </li></ul></ul><ul><ul><li>Fungicide + nitrogen effects may be stronger when more effective fungicides are used or a higher rate of nitrogen applied </li></ul></ul>
  59. 64. Fungicide Summary <ul><li>Fungicides show different responses </li></ul><ul><li>Immediate recovery/Shorter residual </li></ul><ul><ul><li>Headway </li></ul></ul><ul><ul><li>Endorse </li></ul></ul><ul><li>Delayed recovery/Longer residual </li></ul><ul><ul><li>ProStar </li></ul></ul><ul><ul><li>Trinity/Triton </li></ul></ul><ul><ul><li>Tourney (data not shown, but similar to Trinity/Triton applications) </li></ul></ul>
  60. 65. Fungicide Summary <ul><li>Tank mixing fungicides, especially with a the DMI fungicides Banner MAXX, Trinity, Triton or Tourney will increase effectiveness </li></ul><ul><ul><li>For example, 4 oz Endorse + 1 fl oz Banner MAXX gave much better control than Endorse used alone </li></ul></ul><ul><ul><li>Headway, a pre-mix of Heritage & Banner MAXX, gave better results than Heritage or Banner MAXX used alone </li></ul></ul>
  61. 66. Fungicide Summary <ul><li>These fungicides were also shown to be effective, but 2 applications at the high labeled are recommended </li></ul><ul><ul><li>Heritage, Insignia, Disarm </li></ul></ul><ul><ul><li>Medallion, Instrata </li></ul></ul><ul><ul><li>Banner MAXX, Concert </li></ul></ul><ul><ul><li>Renown </li></ul></ul>
  62. 67. Conclusions <ul><li>Nitrogen fertility plays an important role </li></ul><ul><ul><li>Increasing plant health/resistance to attack & recovery from damage </li></ul></ul><ul><li>Primo MAXX benefits outweigh potential negative effects on disease when used with adequate nitrogen fertility </li></ul><ul><li>Timely fungicide applications are needed </li></ul><ul><ul><li>Fast acting/short residual vs slow acting/long residual </li></ul></ul><ul><ul><li>Two back to back applications may work best </li></ul></ul><ul><li>Add brown ring patch to the list of low-fertility diseases like anthracnose & dollar spot </li></ul>
  63. 68. Acknowledgements <ul><li>Torrey Pines Municipal Golf Course </li></ul><ul><ul><li>Wayne Carpenter </li></ul></ul><ul><ul><li>Candice Combs </li></ul></ul><ul><ul><li>Jon Maddern </li></ul></ul><ul><ul><li>Mark Woodward </li></ul></ul><ul><li>GCSAA Environmental Institute for Golf </li></ul><ul><li>California State GCSA </li></ul><ul><li>Southern & Northern California, San Diego, Hi-Lo, and Sierra Nevada GCSAs </li></ul>