Best Management Practices for Anthracnose

Transcription

1 Best Management Practices for Anthracnose Bruce Clarke and James Murphy John Inguagiato, Joseph Roberts, Charles Schmid, James Hempfling, and Ruying Wang turf.rutgers.edu

2 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. anagement.pdf Best management practices for anthracnose on annual bluegrass. Murphy et al. May 2012 GCM. ay104.pdf

3 Anthracnose Symptomology Chlorotic Leaves Acervuli on Infected Poa annua Tillers Photo: Landschoot,

4 Cultural Management Strategies for the Control of Anthracnose

5 31 August inch Mowing Height inch

6 % Disease Mowing Frequency Effect on Anthracnose Severity / wk 7 / wk Jul 13-Aug 27-Aug 10-Sep 24-Sep 8-Oct

7 Lightweight Rolling Practices Effecting Rolled every other day Anthracnose No rolling TRUE-SURFACE TM vibratory rollers

8 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

9 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

10 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

11 Effect of Soluble N Rate on Anthracnose Severity of an Annual Bluegrass Green: Disease Severity (%) lbs 1000 ft lbs 1000 ft lbs 1000 ft lbs 1000 ft lbs 1000 ft Jun Jul Aug Sep-10 Date

12 Anthracnose severity response to total N applied on annual bluegrass in 2009, 2010 and AUDPC Total N (lb 1000 ft -2 )

13 Superintendent Questions: What about granular fertilization?

14 EFFECT OF SEASON OF GRANULAR N FERTILIZATION 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 (%) Jun 01-Jul 01-Aug 01-Sep Jun 01-Jul 01-Aug 01-Sep

15 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 )

16 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

17 Nitrogen Source & Anthracnose Recent studies indicate that N Source affects anthracnose severity

18 Disease Severity (%) EFFECT OF NITROGEN FORM ON DISEASE SEVERITY 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*

19 Potassium can improve winter hardiness and reduce winter injury

20 Snow Melt / Ice Damage (2011 Rutgers Univ.) Potassium Nitrate Ammonium Sulfate

21 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

22 Disease Severity (%) POTASSSIUM SOURCE STUDY N, no K (1:0) KCl, no N (0:1) KCl (1:1) KCl (2:1) First year data KCl (4:1) K2SO4 (1:1) K2SO4 (2:1) K2SO4 (4:1) K2CO3 (1:1) KNO3 (1:1) Jun 15-Jun 29-Jun 13-Jul 27-Jul 10-Aug 24-Aug 7-Sep Date

23 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 : : : 1 1 : : : 1 1 : : * Per 1000-ft 2 Typical potassium recommendation 1 : 1 (N : K 2 O by weight)

24 ANTHRACNOSE POTASSIUM STUDY 10 SEPT No Potassium K 2 SO 4 (1:1)

25 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 )

26 ph Effect on Anthracnose (AUDPC): R 2 = AUDPC Target ph

27 Southern Hills CC, Oklahoma Modify thatch/soil Smooth the surface Sand Topdressing Crown protection Winter protection

28 Impact of Summer Topdressing Rate and Frequency on Anthracnose Interval (days) Rate (ft ft -2 ) No sand 1 (0.3 L m -2 ) 2 (0.6 L m -2 ) All plots brushed uniformly 2 ft ft -2 1 ft ft -2

29 Effect of Topdressing Rate on Anthracnose of Annual Bluegrass sand ft 3 /1,000ft 2 % Disease a b b a b b b a b a b C b a 20.0 a c 10.0 ab b Jun 22-Jun 2-Jul 12-Jul 22-Jul 1-Aug 11-Aug 21-Aug 31-Aug 10-Sep

30 What About Sand Type and Incorporation Method? Incorporation None Vibratory roller Soft-bristled broom Stiff-bristled broom Sand Type Round Sub-angular

31 No Sand Sand 1 ft 3 /1000-ft 2

32 No Sand 1.0 ft 3 /1000-ft ft 3 /1000-ft 2 Topdressing improves surface characteristics Firmer surface raises effective height of cut Deeper crowns reducing stress

33 Topdressing Practices Research indicates that both fall and spring applications reduce anthracnose severity Spring topdressing is the most beneficial timing

34 AUDPC 14 Anthracnose severity response (AUDPC) to total amount of sand applied (L m -2 ) during ,000 lb per 1,000 ft 2 2,000 lb per 1,000 ft Sand L m -2

35 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).

36 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

37 Disease (%) Irrigation Practices Influence on Anthracnose of an Poa annua Green % ET 80% ET 60% ET 40% ET Jun 21-Jun 5-Jul 19-Jul 2-Aug 16-Aug

38 Verticutting Used to improve surface playability and reduce other problems associated with thatch Reputed to enhance anthracnose due to wounding of tissue

39 Verti-cutting Recent detailed studies of mechanical injury indicates that neither wounding of leaves, crowns, nor stolons dramatically affects anthracnose severity

40 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

41 Objective: Examine the effects of mowing height, N fertility, and topdressing on anthracnose severity and playability of ABG turf. Factors: Combining BMPs Mowing height vs inch N Fertility 2.05 vs. 4.1 lb N per 1000 ft 2 per yr Topdressing 950 vs lbs sand 1000 ft -2

42 % Disease % Disease 2012 Fig. 1. Anthracnose severity affected by mowing height in in 40 Fig. 2. Anthracnose severity affected by nitrogen fertility Low N High N 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 Low Sand High Sand Jun 28-Jun 19-Jul 9-Aug 30-Aug 20-Sep 11-Oct

43 Controlling Anthracnose Basal Rot with a Sound Fungicide Program

44 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

45 Efficacy of DMIs on Anthracnose of ABG Green Rutgers 2009 c % Turf Area Infested 14 day (15 May 21 Aug)

46 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

47 Evaluating Tank Mixtures for the Control of Anthracnose

48 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

49 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)

50 Objective: To determine the effect of best management practices (BMPs) on fungicide efficacy. Factors: Mowing Height vs 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

51 % Disease Fig. 1. Anthracnose severity affected by mowing height in in Fig. 2. Anthracnose severity affected by nitrogen fertility Low N High N 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!

52 % Disease FUNGICIDE EFFICACY TRIAL: RESULTS NITROGEN X FUNGICIDE RATE INTERACTION* None 25% 50% 75% 100% a % 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 d

53 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 ) % 80% 10% less fungicide than calendar-based schedule

54 For Additional information - Turf.rutgers.edu