New England Regional Turf Conference Providence, RI March 7, 2011

1. More With Less: Getting the Most out of Your
Fungicide Program
Lane P. Tredway
Associate Professor and Extension Specialist
Department of Plant Pathology
North Carolina State University

2. In most cases, you get what you pay for!

3. More with Less?
Fungicide performance is
determined by several
factors that YOU can control.

4. What factors influence fungicide

5. Techniques for Improving
Fungicide Performance
1. Maintain healthy turf
2. Get an accurate diagnosis
3. Select the best fungicide
4. Time applications properly
5. Put the fungicide where the
pathogen is
6. Provide uniform coverage of
the target site
7. Prevent fungicide resistance

6. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

7. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

8. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

9. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

10. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

11. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

12. An apple a day will keep the doctor away....
What does a turf plant need
to be healthy?
1. light
2. air (oxygen)
3. food
4. water
6

13. Nitrogen Fertilization
• nitrogen is the nutrient that
has the greatest impact on
turf growth
• as a result, it has the
greatest impact on disease
development
• every turf disease is
impacted by nitrogen, either
in a positive or negative
way
• some diseases can be
enhanced by EITHER
excessive or deficient
nitrogen
7

14. Nitrogen applications should mirror turf growth.
8

15. Nitrogen excesses are most
problematic
Nitrogen applications should mirror turf growth.
8

16. Nitrogen deficiencies are most
problematic
Nitrogen applications should mirror turf growth.
8

17. Brown patch and Pythium blight are enhanced by high nitrogen levels during
summer. 9

18. dollar spot
anthracnose Pythium root dysfunction
“Low-N” diseases are now the most common and severe problems in golf course
putting greens. 10

19. Get an accurate diagnosis!
• some diseases can be
diagnosed easily in the field
• many cannot and a lab
diagnosis is essential
11

20. Many diseases appear similar from a distance.
Root diseases are difficult to distinguish without the aid of a
microscope.

21. Proper sample collection and shipment are essential to getting an accurate
diagnosis.

22. No disease?
What NOW?!?!?
• nutrient analysis - soil and
tissue
• nematode assays
• monitor soil health
• drainage
• layering
• black layer

23. Soils problems are a common cause of turf decline.
15

24. How do you select the RIGHT
Many fungicides are available one for each application?

25. How do you select a fungicide?

26. How do you select a fungicide?
Heritage (0.2 oz, 28 day) Eagle (1.2 oz, 14 day)

27. Fungicide Selection
References
• Product Labels
• Chemical Control of Turfgrass
Diseases
• Pest Control for Professional
Turf Managers
• TurfFiles Disease Profiles
• TurfFiles Fungicide Selection
Tool

28. Selecting the right fungicide is key to success
Banner Maxx (4 fl oz)
Eagle 20EW (2.4 fl oz)
Heritage 50WG (0.4 oz)
Insignia (0.9 oz)
Compass (0.25 oz)
Headway (1.5 fl oz)
Armada (1.2 oz)
Bayleton (2 oz)
Trinity (2 oz)
Untreated
0 7.5 15 22.5 30
Summer Patch on Kentucky Bluegrass
Treatments applied May 2, May 29, and Jun 26
Data collected 10 Sept

29. Selecting the right fungicide is key to success
Curalan (1 oz)
26/36 (4 fl oz)
Endorse (4 oz)
Tourney (0.18 oz)
Heritage TL (1 fl oz)
Untreated
0 3.75 7.5 11.25 15
Anthracnose of Creeping Bentgrass
Treatments applied on 14 day interval beginning 9
Jun
Data collected 18 Aug

30. Every Fungicide Has Three Different Names
Chemical Name
• tetrachlorothaloisonitrile
Common Name
• chlorothalonil
Trade Name(s)
• Daconil, Chlorstar,
Concorde, Echo, Manicure,
etc.

31. Turfgrass Fungicides: 15 Chemical Classes
• Aromatic hydrocarbon • Phenylamide
• Benzimidazole • Phenylpyrolle
• Carbamate • Phosphonate
• Carboxamide • Polyoxin
• Dicarboximide • Pyridine
• Dithiocarbamate • QoI
• DMI • QiI
• Nitrile

32. FRAC codes are displayed prominently on new fungicide labels

33. Pre-mix products contain more than one chemical class.

34. What you need to know
about fungicides
Topical Mode of Action
• how does the fungicide move
on/in the plant after
application?
Biochemical Mode of Action
• what is the risk for fungicide
resistance?
• single-site or multi-site
inhibitor

35. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact
• localized penetrant
• systemic
• acropetal penetrant
• true systemic

36. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact stays on leaf surface
• localized penetrant
• systemic
• acropetal penetrant
• true systemic

37. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact
• localized penetrant absorbed into leaf
• systemic
• acropetal penetrant
• true systemic

38. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact
• localized penetrant
• systemic absorbed and
• acropetal penetrant
• true systemic

39. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact
• localized penetrant
• systemic
• acropetal penetrant moves upward
• true systemic

40. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact
• localized penetrant
• systemic
• acropetal penetrant
• true systemic moves up and down

41. Topical Mode of
Action
How the fungicide moves on/in
plant after it is applied
• contact
• localized penetrant
• systemic
• acropetal penetrant
• true systemic

42. Topical mode of action determines how a fungicide moves on/in the plant
after application.

43. Why is topical mode of action important?
• determines length of residual control
• contacts and localized penetrants less effective for curative applications
• acropetal penetrants and true systemics best for control of root diseases
• when tank mixing to improve disease control, mixture components should
have different topical modes of action

44. Biochemical Mode of
Action
Single-Site Inhibitors
• inhibit one biochemical
process in the pathogen
• high risk for fungicide
resistance
Multi-Site Inhibitors
• inhibit more that one (2-1000)
processes in the pathogen
• low or moderate resistance
risk

45. Do they work as well as the
Generic Fungicides ‘brand name’ products?

46. Many fungicides are now post-patent
• chlorothalonil • phosphorous acid
• ethazole • propamocarb
• fosetyl-Al • propiconazole
• iprodione • thiophanate-methyl
• mancozeb • triticonazole
• mefanoxam • vinclozolin
• myclobutanil

47. Daconil, Chlorstar, Concord, Echo....
What’s the difference?
What is different? What isn’t different?
• formulation • active ingredient
• packaging
• customer service
• price

48. Chlorothalonil formulations vary in their effectiveness
200
Dollar spot incidence (spots/plot)
150
100
50
0
x
F
F
tik
T
0
ed
e
72
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SS
ltr
rs
at
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ho
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rd
Ec
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on
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ac
on
C
il
D
C
on
ac
D
**All products applied at 2.7 oz a.i. per 1000 ft2; data collected 14 days after one application
Data provided by B.B. Clarke, Rutgers University

49. Many generic products are equally effective
Banner Maxx (1 fl oz) Propiconazole Pro (1 fl oz)
150 Untreated
Dollar Spot Incidence (spots/
120
90
plot)
60
30
0
5/6 5/22 5/27 6/3 6/12 6/18 6/25 7/1 7/8 7/16

50. Products may differ in formulation type
Active Ingredient ME EC
Subdue Maxx,
mefanoxam Mefanoxam
Fenox
Banner Maxx,
propiconazole Propiconazole Pro, Spectator
Savvi

51. Products may also differ in a.i. content
thiophanate-
Product chlorothalonil
methyl
Spectro 72% 18%
SysTec 50% 17%

52. Products may also differ in a.i. content
9
Turfgrass Quality (0 to 9)
6
3
0
Spectro (2 oz) Spectro (4 oz) Consyst (2 oz) Consyst (4 oz) Untreated
Treatments applied every 14 days from 17 Apr to 26 Jun

53. What are you mixing
with your fungicides?
• other fungicides/herbicides/
insecticides
• fertilizers
• growth regulators
• biostimulants
• surfactants/wetting agents

54. Surfactants can improve disease control or extend application intervals.
39

55. They can just as easily REDUCE performance....
a
Fairy Ring Severity (0 to 9)
ab
b b
b
b

56. ...or increase the risk of phytotoxicity
4
Bayleton 4SC (2 oz/1000 sq ft)
Triton 70WG (0.25 oz/1000 sq ft)
Untreated
3
Phytotoxicity (0-9)
a
2
1 b
bc
bc
c c
0
+ Revolution - Revolution

57. Jar Test for Physical
Compatibility
• 1 quart of water
• liquid products
• 1 fl oz = 0.75 teaspoon
• dry products
• 1 oz = 3.5 grams
• shake for 15 seconds
• allow to stand for 15 minutes

58. Why are you tank-mixing fungicides?

59. Why are you tank-mixing fungicides?
Increase control spectrum
• more common as fungicides become more specific
• most pre-mix products fall into this category

60. Why are you tank-mixing fungicides?
Increase control spectrum
• more common as fungicides become more specific
• most pre-mix products fall into this category
Improve disease control
• for difficult-to-control diseases

61. Why are you tank-mixing fungicides?
Increase control spectrum
• more common as fungicides become more specific
• most pre-mix products fall into this category
Improve disease control
• for difficult-to-control diseases
Enhance curative control
• contact + acropetal penetrant is best

62. Why are you tank-mixing fungicides?
Increase control spectrum
• more common as fungicides become more specific
• most pre-mix products fall into this category
Improve disease control
• for difficult-to-control diseases
Enhance curative control
• contact + acropetal penetrant is best
Prevent fungicide resistance
• mix multiple chemical classes that have activity against the disease

63. Pre-mix products provide increased control spectrum
Bayleton anthracnose Tartan
anthracnose brown patch anthracnose
brown patch leaf spot brown patch
copper spot gray leaf spot dollar spot
dollar spot pink patch gray leaf spot
fairy ring pink snow mold fairy ring (soon)
gray leaf spot rapid blight leaf spot
large patch red thread pink patch
pink snow mold rust pink snow mold
powdery mildew summer patch red thread
rusts rust
southern blight southern blight
stripe smut stripe smut
summer patch summer patch
take-all patch
Compass

64. Tank-mixtures may improve control of some diseases
Untreated
Disarm (0.36 fl oz)
Insignia (0.9 oz)
Heritage (0.2 oz)
Daconil Ultrex (3.2 oz)
Signature (4 oz)
Daconil + Signature
0 7.5 15 22.5 30
Anthracnose Incidence (%)

65. Curative control of brown patch in creeping bentgrass
Heritage (0.4 oz) Daconil (3.2 oz) Heritage + Dac (0.4 + 3.2 oz)
Untreated
70
60
Brown patch Incidence (%)
50
40
30
20
10
0
0 5 10 15 20
Days after application

66. Foliar Diseases
Schedule applications based on
low night temperature
• dollar spot >50ºF
• brown patch >60ºF
• Pythium blight >65ºF

67. Root Diseases
Schedule applications based on
average daily soil temperature
• summer patch >65ºF
• take-all patch - 40 to 60ºF
• spring dead spot - 60 to 80ºF
• large patch - 40 to 70ºF
• fairy ring - 55 to 65ºF

68. Selecting an Application Rate

69. Selecting an Application Rate
Preventative Applications
• before fungal infections occur
• use low rate on short intervals
or high rate at long intervals
• all topical modes of action are
effective

70. Selecting an Application Rate
Preventative Applications
• before fungal infections occur
• use low rate on short intervals
or high rate at long intervals
• all topical modes of action are
effective
Curative Applications
• after fungal infections occur
• use high rates at short intervals
• acropetal penetrants are best
• tank-mix with a contact
fungicide is often beneficial

71. Proper placement is crucial Where is the pathogen

72. apply in 1 to 2 gallons
per 1000 ft2
Proper placement is crucial Where is the pathogen

73. apply in 1 to 2 gallons
per 1000 ft2
apply in 2 to 3 gallons
per 1000 ft2
Proper placement is crucial Where is the pathogen

74. apply in 1 to 2 gallons
per 1000 ft2
apply in 2 to 3 gallons
per 1000 ft2
apply in 5 gallons per 1000 ft2
OR
water-in with 1/8” of irrigation
Proper placement is crucial Where is the pathogen

75. When to irrigate?
• How quickly will the spray dry
on the leaves?
• How quickly is the fungicide
absorbed?
• How important are root
diseases as compared to foliar
and crown diseases?

76. take-all patch fairy ring
Post-application irrigation is essential for control of root diseases like
summer patch, take-all patch, and fairy ring.

77. Nozzle Type Determines Fungicide Performance
Flat Fan Nozzle
Raindrop Nozzle
Images from Couch, 1985

78. Raindrop Nozzle Flat Fan Nozzle
Diquat applied @ 1 oz per 1000 ft2
Which nozzle will provide the
Uniform coverage is essential best disease control?

79. Images courtesy Mike Agnew, Syngenta Professional Products
XR Flat Fan Air-induction Flat Fan TurfJet Flat Fan
Fine to medium Coarse to very coarse Extremely coarse
droplets droplets droplets
Flat fan nozzles are no longer
It’s all about droplet size!
created equal

80. Images courtesy Mike Agnew, Syngenta Professional Products
XR Flat Fan TurfJet Flat Fan
Fine to medium Extremely coarse
droplets droplets
Medium to coarse droplets provide the best control of foliar diseases.

81. Formulations respond differently to water volume!
0.5 gal
Daconil Ultrex
1 gal
2 gal
Concorde DF
Echo 90DF
Daconil Wstik
Concorde SST
Echo 720
0 2 4 6 8
Dollar Spot Incidence (spots/plot)
All products applied to deliver 2.7 oz a.i. per 1000 sq ft on 14 day intervals
Data collected 15 Aug 2002
Wong et al., Rutgers University

82. Water volume is most important for root and crown diseases!
35 AI (1 gal)
TT (1 gal)
30
Anthracnose Incidence (%)
XR (1 gal)
25
AI (2 gal)
TT (2 gal)
20 XR (2 gal)
Untreated
15
10
5
0
July 20 August 3
Medallion applied at 0.25 oz/1000 ft2
Courtesy M.A. Fidanza, Penn State University

83. Dew removal improves foliar disease control
AM application AM application
dew not removed dew removed
Daconil Ultrex applied at 1.8 oz/1000 ft2
Courtesy P.H. Dernoeden, University of Maryland