Progress 10/01/13 to 09/30/14
Outputs
Target Audience: The target audience includesgolf course superintendents and industry stakeholders managing annual bluegrass putting green turf. Information was presented atExtension presentations to stakeholders in New England. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest? Results have been disseminated to 300 golf course superintendents through presentations at educational seminars and a research field day. What do you plan to do during the next reporting period to accomplish the goals? Two ongoing field studies on seasonal nitrogen programming with and without plant growth regulators and optimizing preventive fungicide application timing for anthracnose control will be repeated to confirm initialresults. A peer-reviewed journal article will be submitted and educational opportunities for turfgrass managers will be provided through presentations and field days during 2015.
Impacts
What was accomplished under these goals?
Anthracnose (caused by Colletotrichum cereale) is a destructive fungal disease that can destroy weakened turf and is particularly severe on annual bluegrass (Poa annua). It has been reported to occur on 66% of coursesthroughout the United States and Canada. Outbreaks of anthracnose on golf course putting greens started to increase in frequency and intensity during the mid 1990s ( Dernoeden, 2002; Inguagiato et al., 2008; Landschoot and Hoyland, 1995; Mann and Newell, 2005). Since then researchers have determined that the severity of anthracnose is influenced by many of the management practices used by superintendents. Research improving anthracnose control have saved golf courses as much as $20,000annually per facility in costs associated withrevegetating disease affected areas. Best management practices developed to minimize this disease have helped 73% of golf courses to reduce turf loss to tolerable levels or completelyeliminate the disease. However, further potential exists to enhance our management of this devastating disease to reduce fungicide inputs required for its control. Ethephon and trinexapac-ethyl applied together for seedhead and vegetative control have been shown to reduce anthracnose severity, although this effect has been inconsistent in previous research. Moderate nitrogen fertilization can improveannual bluegrasstolerance to anthracnose. However, the influence of seasonal N programming on the ability of plant growth regulators to reduce anthracnose is not well understood. The second year of a field study was conducted to evaluate potential interactions between seasonal nitrogen fertilization programs, ethephon (ET), and trinexapac-ethyl (TE) application interval on anthracnose severity of ABG putting green turf. Nitrogen treatments included spring or fall applications of 48.8 kg ha-1, or a split application of 12.2 and 36.6 kg ha-1 applied spring and fall respectively. Ethephon was applied at 0 or 3.81 kg a.i. ha-1 twice in April. Trinexapac-ethyl treatment intervals consisted of none, 14 day interval, or every 200 growing degree days (GDD) base 0°C from mid-Apr through July 2013 and August 2014, applied at 0.05 kg a.i. ha-1. Surprisingly, N had little effect on anthracnose severity during 2013. However, spring N treatments consistently reduced disease severity compared to fall only treatments from late June through early August 2014. Ethephon, initially reduced anthracnose severity, although had no effect later in the 2013 season. Ethephon treated turf consistently had reduced anthracnose severity throughout 2014. Trinexapac-ethyl consistently reduced anthracnose severity regardless of application interval in both years. However, TE applied every 200 GDD reduced disease severity more than TE every 14-d during July and August. No consistent interactions were observed. Results to date suggest spring rather than fall N fertilization, ET, and TE applied based on GDD model can reduce anthracnose on annual bluegrass putting green turf. This study will be repeated in 2015 to confirmtreatment effects on anthracnose. A new study was initiated during 2014 to assess optimal fungicide application timings to prevent infection by primary inoculum. Recent research has demonstrated in vitro that C. cereale appresoria are most rapidly produced at temperatures between64 to 79ºF . These conditions correspond with temperatures lower than those encountered when most turf managers typically initiate preventive fungicide programs. Focusing preventive fungicide applications earlier in the seasonwhen the pathogen is most likely to infect the host may enhance disease control and reduce the number of annual applications requiredto control this disease. Daconil Ultrex was initially applied when average daily air temperatures reached 50 (13 April), 57 (12 May), 64 (12 May), or 71 (2 July)°F for 3 consecutive days at rate of 3.25 oz 1000 ft-2. A conventionally timedfungicide applied on 2 Junewas also included. Fungicides were re-applied every 7-d after each initial application. All treatments were arrested at the second week of July and monitored for the onset of symptoms. Fungicides applied at temperatures ranging from 50 to 64°F and the conventional timing provided the greatest anthracnose control throughout the trial. Applications initiated at 71°F provided little disease suppression. This study will be repeated in 2015 to further assess treatment effects on anthracnose.
Publications
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2013
Citation:
Inguagiato, J. 2013. Relationship of canopy reflectance and foliar NO-3-N to anthracnose severity on an annual bluegrass putting green. American Phytopathological Society Annual Meeting.
- Type:
Other
Status:
Published
Year Published:
2014
Citation:
Inguagiato, J., K. Miele, E. Brown, X. Chen, and S. Vose. 2014. Preventive anthracnose control on an annual bluegrass putting green turf, 2013. p. 1-5. In Guillard, K. (ed.) 2013 Annual Turfgrass Research Report. Univ. of Connecticut, Storrs.
- Type:
Other
Status:
Published
Year Published:
2014
Citation:
Inguagiato, J., K. Miele, E. Brown, X. Chen, and S. Vose. 2014. Annual bluegrass control with Xonerate in creeping bentgrass fairway turf, 2013. p. 31-34. In Guillard, K. (ed.) 2013 Annual Turfgrass Research Report. Univ. of Connecticut, Storrs.
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Inguagiato, J. 2013. Relationship of canopy reflectance and foliar NO-3-N to anthracnose severity on an annual bluegrass putting green. Phytopathology 103(6S):S2.65.
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2014
Citation:
Chen, X. and Inguagiato, J. 2014. Seasonal nitrogen programs and plant growth regulator effects on anthracnose severity. 4th Biennial UCONN Turfgrass Field Day. Storrs, CT. July 2014
- Type:
Conference Papers and Presentations
Status:
Other
Year Published:
2014
Citation:
Inguagiato, J. and Henderson, J. 2014. Effect of seedbed preparation on glyphosate efficacy for eradicating existing fairway turf. 4th Biennial UCONN Turfgrass Field Day. Storrs, CT. July 2014
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Progress 01/01/13 to 09/30/13
Outputs
Target Audience: The target audience was golf course superintendents and industry stakeholders managing annual bluegrass putting green turf. Information was presented in extension presentations to stakeholders in New England. Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided? A change in knowledge for turfgrass managers was achieved through presentations focusing on results from anthracnose research studies and through on-site field tours of research plots. The graduate student working on the project has experienced a change in knowledge through conducting research and through mentoring with the project principle investigator. How have the results been disseminated to communities of interest? Results have been disseminated to 375 golf course superintendents through presentations at educational seminars, a webinar and a reserach field day. What do you plan to do during the next reporting period to accomplish the goals? A study assessing the effect of nitrogen and plant growth regulators initiated in 2013 will be repeated in 2014. A new field study will be initated to identify optimal timing of preventive fungicide applications for anthracnose control. A better understanding of when preventive applications need to be initiated should reduce turf losses due to anthracnose, and may reduce the number of fungicide applications applied each year for control of this disease. A peer-reviewed journal article will be submitted and educational opportunties for turfgrass managers will be provided through presentations and field days during 2014.
Impacts
What was accomplished under these goals?
A study evaluating the effect of spring nitrogen fertility and plant growth regulators was initiated in April 2013. Anthracnose developed in the study in early June and progressed rapidly during July. Few treatment differences were evident in the study this year due to the rapid and severe epidemic that occured during July. This study will be repeated in 2014 to assess treatment effects on anthracnose. A fungicide efficacy trial including new and developmental active ingredients was conducted. Tank mixes or rotational programs containing chlorothalonil, a phosphonate, and a green pigment consistently provided the greatest disease control. New active ingredients fluazinam and fluxapyroxad were ineffective in controlling anthracnose.
Publications
- Type:
Journal Articles
Status:
Published
Year Published:
2013
Citation:
Inguagiato, J.C., Murphy, J.A., and Clarke, B.B. 2013. Topdressing sand particle shape and incorporation effects on anthracnose severity of an annual bluegrass putting green. Int. Turfgrass Soc. Res. J. 12:127-133.
- Type:
Other
Status:
Published
Year Published:
2013
Citation:
Inguagiato, J., M. Gagliardi, E. Brown, and R. Platt. 2013. Preventative anthracnose control with various fungicides, 2012. p. 1-7. In Guillard, K. (ed.) 2012 Annual Turfgrass Research Report. Univ. of Connecticut, Storrs.
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Progress 01/01/12 to 12/31/12
Outputs
OUTPUTS: Anthracnose is a devastating fungal disease of annual bluegrass putting greens. Nitrogen fertility has been shown to have a profound effect on the severity of anthracnose epidemics. A field study was conducted at the Plant Science Research Farm in Storrs, CT during 2012 to determine whether anthracnose incidence can be related to field based measurements of nitrogen content in planta. Specifically, estimates of chlorophyll content (CHL) and normalized difference vegetative index (NDVI) using canopy reflectance radiometers, and nitrate-N extracted in sap from leaf clippings, measured with a Cardy Twin nitrate-N meter. Nitrogen was applied at rates from 0.75 to 8.25 lbs N / 1000 sq-ft per year. A separate field study was conducted at the same site to examine the efficacy of experimental and commonly used fungicides for anthracnose control on an annual bluegrass putting green turf. Lastly, annual bluegrass control studies in putting green turf with a new herbicide (methiozolin) were also conducted. PARTICIPANTS: Karl Guillard, Professor of Agronomy, UCONN, collaborator in the design and analysis; Michelle DaCosta, Assistant Professor, UMASS, collaborator for analysis of research samples TARGET AUDIENCES: The target audience was golf course superintendents and industry stakeholders managing annual bluegrass putting green turf. Information was presented in extension presentations to stakeholders in New England. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
A linear relationship between anthracnose severity and chlorophyll index values or NDVI was observed. CHL and NDVI values were lower in plots where anthracnose was more severe. Chlorophyll index values between 264 to 346, and NDVI values between 0.79 to 0.82 minimized anthracnose incidence. No consistent relationship was observed between NO-3-N measured in sap extracted from clippings and anthracnose severity. These data suggest that it may be possible for turf managers to use reflectance meters to guide N fertility practices to minimize anthracnose incidence on putting green turf. Chemical control of anthracnose was most effective with rotational fungicide programs or tank mixtures containing chlorothalonil. Nitrogen applied at 0.1 lb / 1000 sq-ft every 7-d in combination with reduced rates of fungicides also provided excellent anthracnose control in this trial. Methiozolin herbicide provided excellent annual bluegrass control in putting green turf when applied in fall and spring. Higher rates applied 2-3 times in fall provided rapid annual bluegrass control; whereas repeat applications at lower rates applied in spring provided a more gradual control of annual bluegrass. Results from these studies will enhance anthracnose control in annual bluegrass greens through improved nitrogen monitoring techniques to guide fertility applications to reduce disease and reduce fungicide applications by identifying the most efficacious materials to use when needed. New herbicides with improved selectivity and efficacy for controlling annual bluegrass may help superintendents transition to more sustainable turfgrass species such as creeping bentgrass. Results of these studies have been disseminated to industry practitioners in regional educational conferences.
Publications
- Inguagiato, J.C., Murphy, J.A., and Clarke, B.B. 2012. Sand Topdressing Rate and Interval Effects on Anthracnose Severity of an Annual Bluegrass Putting Green. Crop Sci. 52:1406-1415.
- Inguagiato, J.C. 2012. A survey about anthracnose bmps. Golf Course Mange. 80:100-105.
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