Best Management Practices for Anthracnose Bruce Clarke and James Murphy John Inguagiato, Joseph Roberts, Charles Schmid, James Hempfling, and Ruying Wang turf.rutgers.edu
NE-1046 Multi-State Research Project Useful references on BMPs: Best management practices for anthracnose on annual bluegrass turf. Murphy et al. Aug 2008 GCM. http://www2.gcsaa.org/gcm/2008/aug/pdfs/bestm anagement.pdf Best management practices for anthracnose on annual bluegrass. Murphy et al. May 2012 GCM. http://archive.lib.msu.edu/tic/gcman/article/2012m ay104.pdf
Anthracnose Symptomology Chlorotic Leaves Acervuli on Infected Poa annua Tillers Photo: Landschoot,
Cultural Management Strategies for the Control of Anthracnose
31 August 2005 0.141-inch Mowing Height 0.110-inch
% Disease Mowing Frequency Effect on Anthracnose Severity 100 14 / wk 7 / wk 80 60 40 20 0 30-Jul 13-Aug 27-Aug 10-Sep 24-Sep 8-Oct
Lightweight Rolling Practices Effecting Rolled every other day Anthracnose No rolling TRUE-SURFACE TM vibratory rollers
The Take-Home message is you can significantly reduce anthracnose and maintain green speed (ball roll distance) by: (1) increasing heights of cut AND either (2) increasing mowing frequency, and/or (3) initiating frequent lightweight rolling
Nitrogen (N) Fertility Crucial to the health and vigor of the turf, which, in turn, affects playability 0.1 lb per 1000-ft 2 per week (late spring through summer) reduces anthracnose compared to every month 0.2 lb per 1000-ft 2 per week is better
Nitrogen (N) Fertility N at 0.3 to 0.5 lb per 1000-ft 2 per week very effective at reducing anthracnose However, as these rates continued into the summer, we see a dramatic increase in disease
Effect of Soluble N Rate on Anthracnose Severity of an Annual Bluegrass Green: 2010 90 80 Disease Severity (%) 70 60 50 40 30 0.1 lbs 1000 ft -2 0.2 lbs 1000 ft -2 0.3 lbs 1000 ft -2 0.4 lbs 1000 ft -2 0.5 lbs 1000 ft -2 20 10 0 01-Jun-10 01-Jul-10 01-Aug-10 01-Sep-10 Date
Anthracnose severity response to total N applied on annual bluegrass in 2009, 2010 and 2011 50 40 2010 2011 2009 AUDPC 30 20 10 0 0 2 4 6 Total N (lb 1000 ft -2 )
Superintendent Questions: What about granular fertilization?
EFFECT OF SEASON OF GRANULAR N FERTILIZATION 70 60 Autumn Spring 2009 Spring granular-n reduced disease severity more than autumn granular-n Late-season N is not an efficient timing to manage anthracnose disease Summer timing is the most effective time to apply N Spring compliments the summer program Disease Severity (%) Disease Severity (%) 50 40 30 20 10 0 01-Jun 01-Jul 01-Aug 01-Sep 70 60 50 40 30 20 10 2010 0 01-Jun 01-Jul 01-Aug 01-Sep
Season of Granular N Granular N at 4.5 lb per 1,000-ft 2 (2/3 total in each season - IBDU) Autumn Spring 20 July 2009 No Summer N (0 lbs per 1000ft 2 )
2/3 total Spring Granular (IBDU) 0 lbs 1000 ft -2 Summer 20 July 2009 Granular Rate 0 lbs 1.5 lbs 3.0 lbs 4.5 lbs
Nitrogen Source & Anthracnose Recent studies indicate that N Source affects anthracnose severity
Disease Severity (%) EFFECT OF NITROGEN FORM ON DISEASE SEVERITY 80 2012 60 40 20 Calcium Nitrate Urea 0 1-Jun 15-Jun 29-Jun 13-Jul 27-Jul 10-Aug 24-Aug Date * Untreated control not included in statistical analysis Potassium Nitrate Ammonium Sulfate Ammonium Nitrate Untreated Control*
Potassium can improve winter hardiness and reduce winter injury
Snow Melt / Ice Damage (2011 Rutgers Univ.) Potassium Nitrate Ammonium Sulfate
Why Does Nitrogen Source Affect? - N form - Ammoniacal vs. Nitrate - not solely responsible - Potassium - May help uptake of N - Stress tolerance - Soil ph - Ammonium acidifies soil
Disease Severity (%) POTASSSIUM SOURCE STUDY 2012 60 50 N, no K (1:0) KCl, no N (0:1) KCl (1:1) KCl (2:1) First year data 40 30 20 KCl (4:1) K2SO4 (1:1) K2SO4 (2:1) K2SO4 (4:1) K2CO3 (1:1) KNO3 (1:1) 10 0 1-Jun 15-Jun 29-Jun 13-Jul 27-Jul 10-Aug 24-Aug 7-Sep Date
CONVERSION CHART POTASSIUM RATIOS Elemental ratio Ratio by Wt. Ratio by Wt. Pounds of K 2 O Pounds of K 2 O N : K N : K N : K 2 O per application* per year *(16 apps) 1 : 1 1 : 2.8 1 : 3.3 0.34 5.38 2 : 1 1 : 1.4 1 : 1.7 0.17 2.69 4 : 1 1 : 0.7 1 : 0.8 0.08 1.34 * Per 1000-ft 2 Typical potassium recommendation 1 : 1 (N : K 2 O by weight)
ANTHRACNOSE POTASSIUM STUDY 10 SEPT. 2012 No Potassium K 2 SO 4 (1:1)
Anthracnose ph STUDY SULFUR (0.5 AND 1.0 LB 1000FT -2 ) LIME (2.4, 11.7, 24.3, 35.6 AND 46.1 LB 1000FT -2 )
ph Effect on Anthracnose (AUDPC): 2011 30 25 20 R 2 = 0.837 AUDPC 15 10 5 0 4 5 6 7 8 Target ph
Southern Hills CC, Oklahoma Modify thatch/soil Smooth the surface Sand Topdressing Crown protection Winter protection
Impact of Summer Topdressing Rate and Frequency on Anthracnose Interval (days) 7 14 28 Rate (ft 3 1000-ft -2 ) No sand 1 (0.3 L m -2 ) 2 (0.6 L m -2 ) All plots brushed uniformly 2 ft 3 1000 ft -2 1 ft 3 1000 ft -2
Effect of Topdressing Rate on Anthracnose of Annual Bluegrass 0 1 2 sand ft 3 /1,000ft 2 % Disease 80.0 70.0 60.0 50.0 40.0 30.0 a b b a b b b a b a b C b a 20.0 a c 10.0 ab b 0.0 12-Jun 22-Jun 2-Jul 12-Jul 22-Jul 1-Aug 11-Aug 21-Aug 31-Aug 10-Sep
What About Sand Type and Incorporation Method? Incorporation None Vibratory roller Soft-bristled broom Stiff-bristled broom Sand Type Round Sub-angular
No Sand Sand 1 ft 3 /1000-ft 2
No Sand 1.0 ft 3 /1000-ft 2 2.0 ft 3 /1000-ft 2 Topdressing improves surface characteristics Firmer surface raises effective height of cut Deeper crowns reducing stress
Topdressing Practices Research indicates that both fall and spring applications reduce anthracnose severity Spring topdressing is the most beneficial timing
AUDPC 14 Anthracnose severity response (AUDPC) to total amount of sand applied (L m -2 ) during 2009 12 10 8 6 4 2 1,000 lb per 1,000 ft 2 2,000 lb per 1,000 ft 2 0 0 1 2 3 4 5 6 7 Sand L m -2
Irrigation Management Turf growing in saturated soil due to poor surface and slow internal drainage is more susceptible to anthracnose (Sprague and Evaul, 1930; Vargas and Turgeon, 2004).
Irrigation Management Field research has confirmed that drought stress also increases anthracnose severity on annual bluegrass Specifically, deficit irrigation that subjects turf to frequent wilt stress during warm dry weather (e.g., 40 and 60% ET o ) will increase anthracnose disease
Disease (%) Irrigation Practices Influence on Anthracnose of an Poa annua Green 80 70 100% ET 80% ET 60% ET 40% ET 60 50 40 30 20 10 0 7-Jun 21-Jun 5-Jul 19-Jul 2-Aug 16-Aug
Verticutting Used to improve surface playability and reduce other problems associated with thatch Reputed to enhance anthracnose due to wounding of tissue
Verti-cutting Recent detailed studies of mechanical injury indicates that neither wounding of leaves, crowns, nor stolons dramatically affects anthracnose severity
Plant Growth Regulators The widespread use of PGRs on putting green turf over the past decade has coincided with increased incidence of anthracnose Trinexapac-ethyl (Primo MAXX) is used to reduce vegetative growth (increased density & vigor) Mefluidide (Embark) and Proxy (Ethephon) suppresses seedheads
Objective: Examine the effects of mowing height, N fertility, and topdressing on anthracnose severity and playability of ABG turf. Factors: Combining BMPs - 2012 Mowing height 0.090 vs. 0.125 inch N Fertility 2.05 vs. 4.1 lb N per 1000 ft 2 per yr Topdressing 950 vs. 2400 lbs sand 1000 ft -2
% Disease % Disease 2012 Fig. 1. Anthracnose severity affected by mowing height 60 0.090 in 50 0.125 in 40 Fig. 2. Anthracnose severity affected by nitrogen fertility Low N High N 30 20 10 0 7-Jun 28-Jun 19-Jul 9-Aug 30-Aug 20-Sep 11-Oct 7-Jun 28-Jun 19-Jul 9-Aug 30-Aug 20-Sep 11-Oct Fig. 3. Anthracnose severity affected by sand topdressing 60 50 Low Sand High Sand 40 30 20 10 0 7-Jun 28-Jun 19-Jul 9-Aug 30-Aug 20-Sep 11-Oct
Controlling Anthracnose Basal Rot with a Sound Fungicide Program
Chemical Control of Anthracnose I. Demethylation Inhibitors (Sterol Inhibitors) Banner, Bayleton, Eagle, Torque, Tourney, Trinity, Triton II. Strobilurins Heritage, Compass Insignia, Disarm III. Antibiotic Endorse, Affirm IV. Benzimidazoles Fungo, 3336 V. Nitriles Daconil, ChloroStar, Echo, Concorde Combinations (III/IV, I/II, & I/ IV) ConSyst, Spectro, Headway, Tartan, Reserve, Renown, Pillar, Interface, Concert, Disarm C
Efficacy of DMIs on Anthracnose of ABG Green Rutgers 2009 c % Turf Area Infested Applied @ 14 day (15 May 21 Aug)
Good Control of ABR until Late August ٠Phosphonate fosetyl-al Chipco Signature 80WG (4.0 oz) ٠DMI myclobutanil Eagle 40W (1.0 oz) ٠Dicarboximide iprodione Chipco 26GT 2SC (4 fl oz) ٠Phenylpyrrole - fludioxonil Medallion 50W (0.25 oz) Civitas, Daconil Action, Velista? 14 d interval
Evaluating Tank Mixtures for the Control of Anthracnose
Curative Control of Anthracnose Basal Rot on an Annual Bluegrass Green Univ. Riverside, CA Rated on 24 July Applied every 14 days from 15 Jun 1 Sept Wong et al (2002) Plant Dis Mgm t Rpt 1:T064
Chemical Control of Anthracnose New Fungicide Mixtures: Concert (chlorothalonil + propiconazole) Disarm C (fluoxastrobin + chlorothalonil) Disarm M (fluoxastrobin + myclobutanil) Honor (boscalid + pyraclostrobin) Instrata (chlorothalonil + propiconazole + fludioxonil) Interface (iprodione + trifloxystrobin) Pillar (pyraclostrobin + triticonazole) Renown (chlorothalonil + azoxystrobin) Reserve (chlorothalonil + triticonazole) Tartan (trifloxystrobin + triadimefon)
Objective: To determine the effect of best management practices (BMPs) on fungicide efficacy. Factors: Mowing Height 0.090 vs. 0.125 inch N Fertility 2.05 vs. 4.1 lb N per 1000 ft 2 per yr Fungicide Program - Calendar-based 14-day interval at 100%, 75%, 50% and 25% rates of fungicides (3.2 oz/m Dac Ult + 4 oz/m Signature) - Threshold-based schedule at 100% rate of fungicides - None Putting It All Together BMPs Effect on Fungicide Efficacy -2012
% Disease Fig. 1. Anthracnose severity affected by mowing height 40 35 0.090 in 30 0.125 in Fig. 2. Anthracnose severity affected by nitrogen fertility Low N High N 25 20 15 10 5 0 7-Jun 5-Jul 2-Aug 30-Aug 27-Sep 25-Oct 7-Jun 5-Jul 2-Aug 30-Aug 27-Sep 25-Oct N fertility had a greater effect on disease severity than mowing height. N fertility interacted with fungicide program, which means the effectiveness of a fungicide program depended on the level of N fertility!
% Disease FUNGICIDE EFFICACY TRIAL: RESULTS NITROGEN X FUNGICIDE RATE INTERACTION* 80 70 None 25% 50% 75% 100% 60 50 a 40 30 20 10 5% 0 b a c b bc bc d c High N High Low N Low * Interaction data shown from Sept. 14, 2012 is representative of all rating dates in 2012. d
TOTAL # OF FUNGICIDE APPLICATIONS (MAY- SEPT 2012): COMPARISON OF THRESHOLD APPLICATIONS TO COMBINATIONS OF NITROGEN PROGRAMS AND MOWING HEIGHTS Low Mow (0.090 in ) High Mow (0.125 in) Low N (2.05 lbs N 1000 ft -2 yr -1 ) High N (4.1 lbs N 1000 ft -2 yr -1 ) 9 9 5 2 50% 80% 10% less fungicide than calendar-based schedule
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