Field Quantification of Ammonia Emission following Fertilization of Golf Course Turfgrass in Sub/Urban Areas

Low cost and favorable handling characteristics make urea (46-0-0) a leading nitrogen source for frequent, foliar N fertilization of golf course putting greens in season. Yet few field investigations of resulting NH3 volatilization from putting greens have been directed. Meanwhile, NH3 emissions degrade air and surface water quality. Our objective was to quantify NH3 volatilization following practical, low-N rate, and foliar application of commercial urea-N fertilizers. Over the 2019 and 2020 growing seasons in University Park, PA, USA, an industrial vacuum pump, H3BO3 scrubbing flasks, and sixteen dynamic flux chambers were employed in four unique experiments to measure NH3 volatilization from creeping bentgrass putting greens (Agrostis stolonifera L. ‘Penn G2’) in the 24 h period ensuing foliar application of urea based-N at a 7.32 or 9.76 kg/ha rate. Simultaneous and replicated flux chamber trapping efficiency trials showing 35% mean NH3 recovery were used to adjust NH3 volatilization rates from treated plots. Under the duration and conditions described, 3.1 to 8.0% of conventional urea N volatilized from the putting greens as NH3. Conversely, 0.7 to 1.1% of methylol urea liquid fertilizer (60% short-chain methylene urea) or 0.7 to 2.2% of urea complimented with dicyandiamide (DCD) and N-(n-butyl) thiophosphoric triamide (NBPT) volatilized as NH3.

Download Full-text

Occurrence and Molecular Identification of Azoxystrobin-Resistant Colletotrichum cereale Isolates from Golf Course Putting Greens in the Southern United States

Plant Disease ◽

10.1094/pdis-94-6-0751 ◽

2010 ◽

Vol 94 (6) ◽

pp. 751-757 ◽

Cited By ~ 16

Author(s):

Joseph R. Young ◽

Maria Tomaso-Peterson ◽

Lane P. Tredway ◽

Karla de la Cerda

Keyword(s):

United States ◽

Creeping Bentgrass ◽

Amino Acid Sequences ◽

Golf Course ◽

Southern United States ◽

Common Disease ◽

Putting Greens ◽

Qoi Fungicides ◽

Colletotrichum Cereale

Turfgrass anthracnose, caused by Colletotrichum cereale (≡C. graminicola), has become a common disease of creeping bentgrass and annual bluegrass putting greens throughout the southern United States. Strobilurin (QoI) fungicides such as azoxystrobin are single-site mode-of-action fungicides applied to control C. cereale. In vitro bioassays with azoxystrobin at 0.031 and 8 μg/ml incorporated into agar were performed to evaluate the sensitivity of 175 isolates collected from symptomatic turfgrasses in Alabama, Mississippi, North Carolina, Tennessee, and Virginia. Three sensitivity levels were identified among C. cereale isolates. Resistant, intermediately resistant, and sensitive isolates were characterized by percent relative growth based on the controls with means of 81, 23, and 4%, respectively, on media containing azoxystrobin at 8 μg/ml. The molecular mechanism of resistance was determined by comparing amino acid sequences of the cytochrome b protein. Compared with sensitive isolates, C. cereale isolates exhibiting QoI resistance had a G143A substitution, whereas isolates expressing intermediate resistance had a F129L substitution. C. cereale isolates displaying azoxystrobin resistance in vitro were not controlled by QoI fungicides in a field evaluation. The dominance of QoI-resistant C. cereale isolates identified in this study indicates a shift to resistant populations on highly managed golf course putting greens.

Download Full-text

Long-Term Roughstalk Bluegrass Control in Creeping Bentgrass Fairways

Weed Technology ◽

10.1017/wet.2017.72 ◽

2017 ◽

Vol 31 (5) ◽

pp. 714-723

Author(s):

Sandeep S. Rana ◽

Shawn D. Askew

Keyword(s):

Creeping Bentgrass ◽

Golf Course ◽

Cool Season ◽

Putting Greens ◽

Annual Bluegrass ◽

Turf Quality ◽

Normalized Difference Vegetative Index

Methiozolin is an isoxazoline herbicide that selectively controls annual bluegrass in cool-season turf and may control roughstalk bluegrass, another weedyPoaspecies that is problematic in many turfgrass systems. However, the majority of research to date is limited to evaluating methiozolin efficacy for annual bluegrass control in creeping bentgrass putting greens. Research was conducted comparing various application regimes of methiozolin and other herbicides for long-term roughstalk bluegrass control in creeping bentgrass golf fairways. Methiozolin-only treatments did not injure creeping bentgrass or reduce normalized difference vegetative index (NDVI) at 2 golf course locations based on 20 evaluation dates over a 2.5-yr period. The 2.5-yr average turf quality generally declined as roughstalk bluegrass control increased due to transient turf cover loss. At 1 yr after last treatment, methiozolin at 1500 g ai ha-1applied four times in fall reduced roughstalk bluegrass cover 85%. This was equivalent to methiozolin at 1000 g ha-1applied four times in fall, but greater than low rates of methiozolin applied four times in spring or twice in fall and spring. Amicarbazone, primisulfuron, and bispyribac-sodium alone either did not effectively reduce roughstalk bluegrass cover, or did so at the expense of increased creeping bentgrass injury. Results of this study suggest that methiozolin alone or tank-mixed with amicarbazone or primisulfuron is an effective long-term approach for selectively controlling roughstalk bluegrass in creeping bentgrass.

Download Full-text

Use of High-pressure Injection to Alleviate Type-I Fairy Ring Symptoms in Turfgrass

HortTechnology ◽

10.21273/horttech.15.1.0169 ◽

2005 ◽

Vol 15 (1) ◽

pp. 169-172 ◽

Cited By ~ 7

Author(s):

M.A. Fidanza ◽

P.F. Colbaugh ◽

M.C. Engelke ◽

S.D. Davis ◽

K.E. Kenworthy

Keyword(s):

High Pressure ◽

Root Zone ◽

Creeping Bentgrass ◽

Golf Course ◽

Type I ◽

Putting Greens ◽

Pressure Injection ◽

Spray Method ◽

Putting Green ◽

High Pressure Injection

Fairy ring is a common and troublesome disease of turfgrasses maintained on golf course putting greens. Type-I fairy ring is especially destructive due to the development of hydrophobic conditions in the thatch and root zone, thus contributing to turfgrass injury and loss. The objective of this 2-year field study was to evaluate the application and novel delivery method of two fungicides and a soil surfactant for curative control of type-I fairy ring in a 20-year-old creeping bentgrass [Agrostis palustris (synonym A. stolonifera)] putting green. In both years, all treatments were applied twice on a 28-day interval. In 1998, flutolanil and azoxystrobin fungicides were applied alone and in combination with Primer soil surfactant by a conventional topical spray method, and fungicides without Primer applied via high-pressure injection (HPI). Acceptable type-I fairy ring control was observed in plots treated with flutolanil plus Primer, HPI flutolanil, azoxystrobin alone, azoxystrobin plus Primer, or HPI azoxystrobin. In 1999, treatments were HPI flutolanil, HPI flutolanil plus Primer, HPI azoxystrobin, HPI water only, and aeration only. Acceptable type-I fairy ring control was observed in plots treated with HPI flutolanil plus Primer or HPI azoxystrobin. HPI of fungicides alone or in combination with a soil surfactant may be a viable option for alleviating type-I fairy ring symptoms on golf course putting greens.

Download Full-text

Dollar Spot Suppression on Creeping Bentgrass in Response to Repeated Foliar Nitrogen Applications

Plant Disease ◽

10.1094/pdis-05-20-1031-re ◽

2021 ◽

pp. PDIS-05-20-1031 ◽

Cited By ~ 1

Author(s):

Ronald Townsend ◽

Michael D. Millican ◽

Damon Smith ◽

Ed Nangle ◽

Kurt Hockemeyer ◽

...

Keyword(s):

Calcium Nitrate ◽

Creeping Bentgrass ◽

The United States ◽

Fertilizer Application ◽

N Fertilization ◽

Disease Suppression ◽

Golf Course ◽

Dollar Spot ◽

Putting Greens ◽

The Impact

Dollar spot is caused by the fungus Clarireedia spp. and is the most economically important disease of golf course turfgrass in temperate regions of the United States. Previous research has demonstrated that nitrogen (N) fertilization may reduce dollar spot severity, but the results have been inconsistent, and the impact of N as part of repeated foliar fertilization applications to golf course putting greens remains unclear. Two independent trials were replicated in Madison, Wisconsin and Glenview, Illinois in the 2015, 2016, and 2017 growing seasons. The objective of the first trial was to evaluate the effect of four different N rates applied as urea (4.9, 9.8, 19.4, and 29.3 kg N/ha applied every 2 weeks) on dollar spot severity, and the objective of the second trial was to evaluate the effect of three N sources (calcium nitrate, ammonium sulfate, and ammonium nitrate applied every 2 weeks) on dollar spot severity. Results from the N rate trial at both locations indicated that only the highest (29.3 kg N/ha) rate consistently reduced dollar spot severity relative to the nontreated control. Nitrogen source had minimal and inconsistent impacts on dollar spot severity based on location and year. Although these results show that meaningful reductions in dollar spot severity can be achieved by manipulating N fertilizer application rates, the rate of N needed for disease suppression may be impractical for most superintendents to apply and result in undesirable nontarget impacts.

Download Full-text

Effects of Flutolanil Fungicide and Primer Wetting Agent on Water-repellent Soil

HortTechnology ◽

10.21273/horttech.11.3.437 ◽

2001 ◽

Vol 11 (3) ◽

pp. 437-440 ◽

Cited By ~ 7

Author(s):

Keith J. Karnok ◽

Kevin A. Tucker

Keyword(s):

Root Zone ◽

Water Repellency ◽

Creeping Bentgrass ◽

Wetting Agent ◽

Golf Course ◽

Water Repellent ◽

Agrostis Palustris ◽

Putting Greens ◽

Soil Hydrophobicity ◽

Dry Spot

Localized dry spot (LDS) caused by water repellent soil is a common problem on golf course putting greens having a predominately sand root zone. Fairy ring often causes LDS by developing hydrophobic soil. Although the fungicide flutolanil is labeled for the control of fairy ring, golf course superintendents often apply flutolanil to all LDS caused by hydrophobic soil and other conditions. The objective of this study was to determine the effect of flutolanil on an existing hydrophobic soil. The study was conducted on a creeping bentgrass [Agrostis palustris (synonym A. stolonifera)] experimental golf green in which the top 4 inches (10.2 cm) of the root zone was a moderately hydrophobic sand. Six treatments were used: uncored, cored, flutolanil (two applications.), flutolanil + Primer wetting agent (two applications.), Primer (two applications.) and Primer (three applications.). Plots receiving the fungicide and wetting agent treatments were cored before application. Each treatment containing the wetting agent significantly reduced soil water repellency. Flutolanil without wetting agent had no effect on soil hydrophobicity.

Download Full-text

Taxonomic Diversity of Rhizosphere Bacteria in Golf Course Putting Greens at Representative Sites in the Southeastern United States

HortScience ◽

10.21273/hortsci.43.2.514 ◽

2008 ◽

Vol 43 (2) ◽

pp. 514-518 ◽

Cited By ~ 8

Author(s):

Monica L. Elliott ◽

J.A. McInroy ◽

K. Xiong ◽

J.H. Kim ◽

H.D. Skipper ◽

...

Keyword(s):

South Carolina ◽

Cynodon Dactylon ◽

Similarity Index ◽

Acid Methyl Ester ◽

Creeping Bentgrass ◽

Taxonomic Diversity ◽

Golf Course ◽

Culturable Bacteria ◽

Bacterial Populations ◽

Putting Greens

Taxonomic diversity of bacteria associated with golf course putting greens is a topic that has not been widely explored. The purpose of this project was to isolate and identify culturable bacteria from the rhizosphere of creeping bentgrass (Agrostris palustris Huds.) at two sites (Alabama and North Carolina) and hybrid bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt-Davy] at two sites (Florida and South Carolina) for a minimum of 3 years with sampling initiated after the construction process. Randomly selected colonies were identified using gas chromatography for analysis of fatty acid methyl ester profiles. Over 9000 isolates were successfully analyzed. When a similarity index of 0.300 or higher was used, the average number of unidentifiable isolates was 38.6%. The two dominant genera in both bentgrass and bermudagrass rhizospheres were Bacillus and Pseudomonas with Bacillus dominant in bermudagrass and Pseudomonas dominant or equal to Bacillus in bentgrass. Other genera that comprised at least 1% of the isolates at all four sites were Clavibacter, Flavobacterium, and Microbacterium. Arthrobacter also comprised a significant portion of the bacterial isolates in the bentgrass rhizosphere, but not the bermudagrass rhizosphere. Overall, there were 40 genera common to all four sites. At the species level, there were five that comprised at least 1% of the isolates at each location: B. cereus, B. megaterium, C. michiganensis, F. johnsoniae, and P. putida. As has been reported for many grasses, we found considerable taxonomic diversity among the culturable bacterial populations from the rhizospheres of bentgrass and bermudagrass grown in sand-based putting greens.

Download Full-text

Response of Microbial Populations on the Creeping Bentgrass Phyllosphere to Periodic Fungicide Applications

Plant Health Progress ◽

10.1094/php-rs-16-0067 ◽

2017 ◽

Vol 18 (2) ◽

pp. 44-49

Author(s):

Joseph R. Doherty ◽

Megan Botti-Marino ◽

James P. Kerns ◽

David F. Ritchie ◽

Joseph A. Roberts

Keyword(s):

Creeping Bentgrass ◽

Weather Conditions ◽

Deionized Water ◽

Potato Dextrose Agar ◽

Microbial Populations ◽

Golf Course ◽

Biological Processes ◽

Putting Greens ◽

Negative Impacts ◽

The Impact

Fungicides are frequently applied on golf course putting greens to combat the myriad of diseases that can affect them; however, it is unknown how these fungicides may affect microbial populations. Plant-associated microbial communities are intimately involved with plant development and soil biological processes. This two-year study was designed to evaluate the impact of five selected fungicides on culturable actinomycetes, fungi, general bacteria, and fluorescent pseudomonads residing in the turfgrass phyllosphere. Fungicides were applied at label rates on a 14-day interval. Four samples, consisting of five individual turf plants, were taken five days post-application. Samples were homogenized in 1 ml sterile deionized water and serial diluted to 10−3 and 10−5. Each dilution was then plated onto four different media (actinomycete isolation agar, acidified potato dextrose agar, nutrient agar + 1% sucrose, and King’s B) for enumeration of microbial populations. Fungicides had both positive and negative impacts on the culturable microbes tested, although population shifts across all treatments were observed with the prevailing weather conditions. These results show that while response to repeated fungicide application appears to be organism dependent, microbes are not completely removed from the environment.

Download Full-text

Dose responses of silvery-thread moss (Bryum argenteum) to carfentrazone-ethyl

Weed Technology ◽

10.1017/wet.2021.42 ◽

2021 ◽

pp. 1-24

Author(s):

Zane Raudenbush ◽

Steven J. Keeley ◽

Cole Thompson ◽

Mithila Jugulam

Keyword(s):

Dose Response ◽

Creeping Bentgrass ◽

Field Studies ◽

Golf Course ◽

Short Term ◽

Putting Greens ◽

San Luis ◽

Bryum Argenteum ◽

Petri Dishes ◽

Dose Responses

Abstract Carfentrazone-ethyl is one of few herbicides labeled for control of silvery-thread moss (STM) in golf course putting greens, but common use rates are up to three times higher than for broadleaf weeds. Our objective was to determine the efficacy of a single postemergence application of carfentrazone-ethyl for STM control in greenhouse and field dose response studies. In the greenhouse, carfentrazone-ethyl was applied at 0, 14, 28, 56, 112, and 224 g ai ha−1 to pots containing established STM and creeping bentgrass. Percent gametophyte injury was visually estimated at 14, 28, 49, and 77 d after treatment (DAT). Shoot viability was determined by excising shoots from treated pots and plating them in petri dishes containing sand. The 28 and 49 DAT ED90 (dose required to cause 90% gametophyte injury) were 26.8 and 54.3 g ha−1, respectively; both of these doses are substantially lower than the label rates for long- and short-term control, respectively. All doses reduced the viability of transplanted shoots at 10 DAT compared to untreated STM; however, regrowth occurred in all petri dishes by 17 DAT. Field studies were initiated in Manhattan, Kansas and San Luis Obispo, California to corroborate greenhouse results. Averaged across locations, carfentrazone-ethyl applied at 56 and 112 g ha−1 caused 76% and 84% STM injury at 14 DAT, but quickly reduced to 45% and 48% STM injury by 28 DAT, respectively. In greenhouse and field studies, STM recovery did not occur until after 2 wk after treatment (WAT), which indicates the label-stipulated application interval of 2 wk is too short. Our research suggests 56 g ha−1 can provide similar burndown control of STM as compared to the highest label rate (112 g ha−1), and turfgrass managers should consider extending the reapplication interval to 3 or 4 wk when moss recovery is observed.

Download Full-text

First Report of Brown Ring Patch Caused by Waitea circinata var. circinata on Poa annua in Virginia

Plant Disease ◽

10.1094/pdis-93-4-0426a ◽

2009 ◽

Vol 93 (4) ◽

pp. 426-426 ◽

Cited By ~ 2

Author(s):

S. Kammerer ◽

P. F. Harmon ◽

S. McDonald ◽

B. Horvath

Keyword(s):

Creeping Bentgrass ◽

Internal Transcribed Spacers ◽

Poa Annua ◽

Golf Course ◽

Mixed Stands ◽

Putting Greens ◽

First Report ◽

Annual Bluegrass ◽

Plastic Bag ◽

Waitea Circinata

Brown ring patch was first described as a disease of cool-season turfgrass on creeping bentgrass (Agrostis palustris) (4) in Japan and later reported in California on annual bluegrass (Poa annua) (2). Brown ring patch symptoms were observed beginning in December 2007 through spring 2008 on 6 of 18 putting greens on a golf course in Reston, VA. Symptoms included yellow rings and patches of blighted turfgrass on the mixed stands of creeping bentgrass (A. palustris) and primarily annual bluegrass (Poa annua). Chlorosis and blight occurred predominantly on P. annua. A turfgrass sample was received from a consultant in April 2008, and disease severity on affected greens was estimated to be 40%. After incubating for 2 days in a moist chamber, Rhizoctonia-like aerial mycelia were observed. The pathogen was isolated on water agar and potato dextrose agar amended with thiophanate-methyl (100 mg/L), rifampicin (100 mg/L), and ampicillin (500 mg/L) from P. annua plants that had been surface sterilized with 70% ethanol for 15 s. Colony and sclerotia morphology were consistent with Waitea circinata var. circinata as previously described (2,4). Hyphae were stained with aniline blue and multiple nuclei were observed per cell. The teleomorph was not observed on plant material or in culture. Amplified fragments of rDNA including internal transcribed spacers from the isolate were amplified in three bacterial clones and sequenced bidirectionally (GenBank Accession Nos. FJ154894, FJ154895, and FJ154896) using primers ITS1/ITS4 (2,4). The consensus sequences matched, with 99% homology and 99% sequence overlap, isolate TRGC1.1 of W. circinata var. circinata (GenBank Accession No. DQ900586) (2). Annual bluegrass was not available for use in performing Koch's postulates, but previous studies have shown that W. circinata var. circinata is pathogenic to roughstalk bluegrass (P. trivialis) (1,3). Pots of P. trivialis cv. Cypress that were 1 week postemergence were inoculated with seven wheat grains that had been autoclaved and then infested with the isolate. Plants were incubated at 25°C in a sealed plastic bag with a moist paper towel on the bottom. Hyphae grew from the grains and colonized the grass. Individual plants began to turn chlorotic within 3 days, and more than 80% of the turf in pots was dead after 1 week. Control pots were inoculated with autoclaved wheat seed and showed no disease symptoms after 1 week. Inoculations were repeated twice more with the same results. W. circinata var. circinata was reisolated from affected plants in all replications of the test. To our knowledge, this is the first report of brown ring patch in Virginia. Additional research is needed to assess the prevalence and importance of this disease on golf course putting greens in Virginia. References: (1) C. M. Chen et al. Plant Dis. 91:1687, 2007. (2) K. A. de la Cerda et al. Plant Dis. 91:791, 2007. (3) N. Flor et al. Plant Dis. 92:1586, 2008. (4) T. Toda et al. Plant Dis. 89:536, 2005.

Download Full-text

Creeping Bentgrass (Agrostis stolonifera) Golf Green Tolerance to Bispyribac-Sodium Tank-Mixed with Paclobutrazol

Weed Technology ◽

10.1614/wt-d-10-00148.1 ◽

2012 ◽

Vol 26 (1) ◽

pp. 145-150 ◽

Cited By ~ 2

Author(s):

Justin Q. Moss ◽

Xi Xiong ◽

Kemin Su ◽

Bishow P. Poudel ◽

John B. Haguewood

Keyword(s):

Creeping Bentgrass ◽

Field Trials ◽

Agrostis Stolonifera ◽

Golf Course ◽

Putting Greens ◽

Annual Bluegrass ◽

Turf Quality ◽

Putting Green ◽

Zone Field ◽

Weekly Application

Annual bluegrass is a troublesome weed in golf course putting greens. The objective of this research was to evaluate creeping bentgrass putting green tolerance to bispyribac-sodium tank-mixed with paclobutrazol in the transition zone. Field trials with four replications were conducted in Oklahoma during 2009 and 2010 and in Missouri during 2010. The results of this study suggest that tank-mixing bispyribac-sodium with paclobutrazol may discolor creeping bentgrass putting greens but will not reduce turf quality below acceptable levels. Normalized vegetative difference index readings indicated no treatment differences in turf greenness at 4 and 8 wk after initial treatment. Weekly application of bispyribac-sodium at 12.4 g ha−1 or biweekly application at 24.8 g ha−1 alone or with monthly applications of paclobutrazol at 224 g ha−1 did not cause unacceptable injury to creeping bentgrass putting greens during the spring.

Download Full-text