scholarly journals Trinexapac-ethyl Application Regimens Influence Creeping Bentgrass Putting Green Performance

HortScience ◽  
2005 ◽  
Vol 40 (7) ◽  
pp. 2167-2169 ◽  
Author(s):  
Patrick E. McCullough ◽  
Haibo Liu ◽  
Lambert B. McCarty
Keyword(s):  
Heat Stress ◽  
Plant Growth Regulator ◽  
Field Experiments ◽  
Acid Ethyl Ester ◽  
Creeping Bentgrass ◽  
Green Performance ◽  
Summer Heat ◽  
Putting Green ◽  
Repeated Applications ◽  
Cyclohexane Carboxylic Acid

Trinexapac-ethyl (TE) is a plant growth regulator registered for periodic applications on creeping bentgrass greens but ball roll as affected by various TE regimens have not been reported. Field experiments were conducted in Clemson, S.C., from May to July 2003 and 2004 on an `L-93' creeping bentgrass putting green. Turf received a total of 0.2 kg·ha–1 a.i. of TE over 12 weeks in three application regimens: 0.017 kg·ha–1 per week, 0.033 kg·ha–1 per 2 weeks, and 0.05 kg·ha-1 per 3 weeks plus a control. Ball roll distances were measured weekly with a stimpmeter in the morning (900 to 1100 hr) and evening (>1700 hr). Morning ball roll distances were generally longer than evening. Ball roll distances increased from June to July 2003 and from May to July 2004, likely resulting from greater bentgrass summer heat stress during the test period. Turf treated with biweekly and triweekly TE regimens had enhanced ball roll on three and four dates, respectively, but inconsistencies occurred likely from reduced efficacy with greater time between repeated applications. Weekly TE applications enhanced ball roll distances from the untreated by 5% to 8% on six dates. Turf injury did not occur following TE applications regardless of regimen. Overall, weekly TE applications increased ball roll distances more frequently than biweekly and triweekly regimens, but enhancements were inconsistent over the 2 years. Chemical name used: [4-(cyclopropyl-[α]-hydroxymethylene)-3,5-dioxo-cyclohexane carboxylic acid ethyl ester] (trinexapac-ethyl); (tetrachloroisophthalonitrile) (chlorothalonil); [methyl(E)-2-(2-(6-(2-cyanophenoxy) pyrimidin-4-yloxy)phenyl)-3-methoxyacrylate] (azoxystrobin); [aluminum tris(0-ethyl phosphonate)] (fosetyl-al); [N-(2,6-Dimethylphenyl)-N-(methoxyacetyl) alanine methyl ester] (metalaxyl); [(1-[[2-(2,4-dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl) -methyl]-14-1,2,4-triazole] (propiconazole).

scholarly journals Ethephon and Gibberellic Acid Inhibitors Influence Creeping Bentgrass Putting Green Quality and Ball Roll Distances

HortScience ◽  
2005 ◽  
Vol 40 (6) ◽  
pp. 1902-1903 ◽  
Author(s):  
Patrick E. McCullough ◽  
Haibo Liu ◽  
Lambert B. McCarty
Keyword(s):  
Field Experiments ◽  
Acid Ethyl Ester ◽  
Creeping Bentgrass ◽  
Agrostis Stolonifera ◽  
Turf Quality ◽  
Green Ball ◽  
Subsequent Application ◽  
Putting Green ◽  
Ethephon Treatment ◽  
Cyclohexane Carboxylic Acid

Plant growth regulators (PGRs) are often applied in combinations to reduce turf clippings, enhance turf quality, and suppress Poa annua L.; however, effects of PGR combinations on putting green ball roll distances have not been reported. Two field experiments were conducted on an `L-93' creeping bentgrass (Agrostis stolonifera var. palustris Huds.) putting green in Clemson, S.C., to investigate effects of four PGRs with and without a subsequent application of ethephon at 3.8 kg·ha–1 a.i. 6 days after initial treatments. The PGRs initially applied included ethephon at 3.8 kg·ha–1 a.i., flurprimidol at 0.28 kg·ha–1 a.i., paclobutrazol at 0.28 kg·ha–1 a.i., and trinexapac-ethyl at 0.05 kg·ha–1 a.i.. Ball roll distances were enhanced 3% to 6% (4 to 8 cm) by exclusive flurprimidol, paclobutrazol, and trinexapac-ethyl treatments. The additional ethephon application reduced ball distances 2% to 9% (2 to 11 cm). Paclobutrazol and trinexapac-ethyl treated turf receiving the additional ethephon application had longer or similar ball roll distances to non-PGR treated turf. The additional ethephon treatment reduced turf quality to unacceptable levels 1 and 2 weeks after applications. However, bentgrass treated previously with trinexapac-ethyl and paclobutrazol had 8 to 16% higher visual quality following the additional ethephon treatment relative to non-PGR treated turf receiving the subsequent ethephon application. Overall, ethephon may have deleterious effects on monostand creeping bentgrass putting green quality and ball roll distances; however, applying ethephon with GA inhibitors could mitigate these adverse effects. Chemical names used: [4-(cyclopropyl-[α]-hydroxymethylene)-3,5-dioxo-cyclohexane carboxylic acid ethyl ester] (trinexapac-ethyl); {α-(1-methylethyl)-α-[4-(trifluoro-methoxy) phenyl] 5-pyrimidine-methanol} (flurprimidol); (+/-)–(R*,R*)-β-[(4-chlorophenyl) methyl]-α-(1, 1-dimethyl)-1H-1,2,4,-triazole-1-ethanol (paclobutrazol); [(2-chloroethyl)phosphonic acid] (ethephon).

scholarly journals Mowing Operations Influence Creeping Bentgrass Putting Green Ball Roll following Plant Growth Regulator Applications

HortScience ◽  
2005 ◽  
Vol 40 (2) ◽  
pp. 471-474 ◽  
Author(s):  
Patrick E. McCullough ◽  
Haibo Liu ◽  
Lambert B. McCarty
Keyword(s):  
Plant Growth ◽  
Plant Growth Regulator ◽  
Acid Ethyl Ester ◽  
Creeping Bentgrass ◽  
Clemson University ◽  
The Third ◽  
Equal Ball ◽  
Green Ball ◽  
Putting Green ◽  
Cyclohexane Carboxylic Acid

Plant growth regulators (PGRs) are commonly used to enhance putting green quality and ball roll distances but their effects with various mowing operations have not been reported. Three experiments were conducted and repeated at Clemson University, Clemson, SC, on an `L-93' creeping bentgrass putting green to evaluate the effects of mowing operations and PGRs on diurnal ball roll distances. The PGRs tested included ethephon at (a.i.) 3.8 kg·ha-1, flurprimidol at (a.i.) 0.28 kg·ha-1, paclobutrazol at (a.i.) 0.28 kg·ha-1, and trinexapac-ethyl at (a.i.) 0.05 kg·ha-1. Mowing operations tested included rolling vs. mowing, morning mowing vs. morning plus afternoon mowing, and single vs. double morning mowing, all with and without PGRs. PGR by mowing operation interactions did not occur in any experiments. Ball roll distances decreased from 12:00 hr to evening observations in all experiments. In Experiment 1, rolling the green without mowing reduced ball roll distance 4% (5 cm) compared to mowing. Turf rolled without mowing in the morning and treated with flurprimidol, paclobutrazol, and trinexapac-ethyl produced similar ball roll at 12:00, 15:00, and 18:00 hr to mowed untreated turf. In Experiment 2, all plots were mowed at 08:00 hr and half of each plot was remowed at 12:30 hr. The second mowing at 12:30 hr enhanced ball roll distances 6% (8 cm) over the day. Turf mowed only at 08:00 and treated with paclobutrazol and trinexapac-ethyl had greater or equal ball roll distances at 12:30, 15:30, and 18:30 hr to untreated turf that had a second mowing at 12:30 hr. Turf receiving ethephon and 08:00 hr mowing had 4% to 12% (4 to 17 cm) shorter ball roll distances throughout the day compared to untreated turf mowed at 8:00 and 08:00+12:30 hr, respectively. In the third experiment, mowing twice in the morning increased ball roll 3% (4 cm) compared to mowing once. Trinexapac-ethyl and paclobutrazol treated turf mowed once in the morning had greater or equal ball roll distances throughout the day to untreated turf mowed twice in the morning. Overall, PGR use may provide putting green ball roll distances similar to or greater than untreated turf despite additional mowing; however, ethephon reduced ball roll distances regardless of mowing operations. Chemical names used: [4-(cyclopropyl-[α]-hydroxymethylene)-3,5-dioxo-cyclohexane carboxylic acid ethyl ester] (trinexapac-ethyl); {α-(1-methylethyl)-α-[4-(trifluoro-methoxy) phenyl] 5-pyrimidine-methanol} (flurprimidol); (+/-)-(R*,R*)-β-[(4-chlorophenyl) methyl]-α-(1, 1-dimethyl)-1H-1,2,4,-triazole-1-ethanol (paclobutrazol); [(2-chloroethyl)phosphonic acid] (ethephon).

scholarly journals Total Nonstructural Carbohydrate Storage in Creeping Bentgrass Treated with Trinexapac-ethyl

HortScience ◽  
2004 ◽  
Vol 39 (6) ◽  
pp. 1461-1464 ◽  
Author(s):  
Sangwook Han ◽  
Thomas W. Fermanian ◽  
John A Juvik ◽  
Louis A. Spomer
Keyword(s):  
Field Experiments ◽  
Acid Ethyl Ester ◽  
Creeping Bentgrass ◽  
Cool Season ◽  
Total Nonstructural Carbohydrates ◽  
Carbohydrate Storage ◽  
Turf Quality ◽  
Loam Soil ◽  
Cyclohexane Carboxylic Acid

Total nonstructural carbohydrates (TNC) are important for summer recuperation from injury for cool-season turfgrass. The objectives of this study were to determine if trinexapac-ethyl (TE) [4-(cyclopropyl-a-hydroxy-methylene)-3,5-dioxo-cyclohexane-carboxylic acid ethyl ester] affects TNC content and turf quality of a creeping bentgrass at various application frequencies and rates and to investigate any interactions between the effects of TE and traffic treatments on TNC content. Field experiments were conducted in 1995 and 1996 on a mature stand of `Pennlinks' creeping bentgrass grown on a Flanagan silt loam soil maintained at a height of 1.9 cm. Treatments included a single application (0.28 kg·ha-1) or repeat applications at 2 (0.06 kg·ha-1) or 4 (one at 0.28 kg·ha-1 and one at 0.09 kg·ha-1) week intervals during the first 8 weeks of each experiment. Treatments were arranged in a strip-plot design with TE applications as whole plots and traffic treatments as strip plots. Traffic treatments began at 2 weeks and 2 days after initial applications in 1995 and 1996, respectively and continued until the last evaluation date. Traffic treatments consisted of 4 passes of a 102.2 kg smooth roller, 2 days·week-1 in 1995 and 8 passes daily in 1996. A single aqueous extraction method was used for quantification of glucose, fructose, sucrose, and fructan. TNC was the total of all analyzed fractions. Single applications of TE at 0.28 kg·ha-1 significantly reduced turf quality for 4 weeks in both experiments. Sequential applications of TE at 0.06 kg·ha-1 exhibited reduced quality compared to the control at 4 and 8 weeks in 1995 and 2 weeks in 1996. When TE was applied once at 0.28 kg·ha-1, there was a significant reduction in TNC from 4 to 8 weeks after treatment. In 1996 when TE applications were repeated at 2 and 4 week intervals at 0.06 and 0.09 kg·ha-1, a reduction of TNC from week 4 to week 14 was observed. After 14 weeks the TNC content showed incremental increases. There was no interaction effect between traffic treatments and TE applications in the verdure TNC in either year. In 1996, verdure TNC content was 6% to 17% lower in plots receiving traffic from weeks 4 to 18. These results suggest that high rates of TE, either sequential or single applications, might reduce turf quality or carbohydrate content. While this study has not examined if this is detrimental, multiple TE applications at low rates may minimize any TNC reduction while providing effective growth suppression for extended periods.

scholarly journals Bermudagrass Putting Green Performance Influenced by Nitrogen and Trinexapac-ethyl

HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 802-804 ◽  
Author(s):  
Patrick E. McCullough ◽  
Haibo Liu ◽  
Lambert B. McCarty ◽  
Joe E. Toler
Keyword(s):  
Shoot Growth ◽  
Field Experiments ◽  
Cynodon Dactylon ◽  
Acid Ethyl Ester ◽  
Time Of Day ◽  
Putting Greens ◽  
Green Ball ◽  
Putting Green ◽  
N Fertility ◽  
Cyclohexane Carboxylic Acid

Dwarf-type bermudagrass (Cynodon dactylon Pers. × C. transvaalensis Burtt-Davy) putting greens tolerate long-term mowing heights of 3.2 mm but require heavy nitrogen (N) fertilizations that increase ball roll resistance. Applying a plant growth regulator, such as trinexapac-ethyl (TE), could reduce uneven shoot growth from high N fertility and improve putting green ball roll distances. Field experiments were conducted from April to August 2003 and 2004 in Clemson, SC to investigate effects of ammonium nitrate applied at 6, 12, 18, or 24 kg N/ha per week with TE applied at 0 or 0.05 kg a.i. per ha every 3 weeks on `TifEagle' bermudagrass ball roll distances (BRD). BRD were measured weekly with a 38-cm stimpmeter in the morning (900 to 1100 hr) and evening (>1700 hr) beginning 1 wk after initial TE treatments. Interactions were not detected among N, TE, or time of day. TE increased BRD about 15% from non-TE treated. BRD was reduced with increased N rate and from am to pm; however, bermudagrass treated with TE averaged 10% longer PM BRD than am distances of non-TE treated. Overall, increased N fertility and diurnal shoot growth may reduce BRD but TE will be an effective tool for mitigating these effects on bermudagrass putting greens. Chemical name used: [4-(cyclopropyl-[α]-hydroxymethylene)-3,5-dioxo-cyclohexane carboxylic acid ethyl ester] (trinexapac-ethyl).

Creeping Bentgrass (Agrostis stolonifera) Putting Green Tolerance to Bispyribac-Sodium

2009 ◽  
Vol 23 (3) ◽  
pp. 425-430 ◽  
Author(s):  
Patrick E. McCullough ◽  
Stephen E. Hart
Keyword(s):  
Growth Inhibition ◽  
Field Experiments ◽  
Creeping Bentgrass ◽  
Agrostis Stolonifera ◽  
Root Weight ◽  
Putting Greens ◽  
Annual Bluegrass ◽  
Greenhouse Experiments ◽  
Chelated Iron ◽  
Putting Green

Bispyribac-sodium is an efficacious herbicide for annual bluegrass control in creeping bentgrass fairways, but turf tolerance and growth inhibition may be exacerbated by low mowing heights on putting greens. We conducted field and greenhouse experiments to investigate creeping bentgrass putting green tolerance to bispyribac-sodium. In greenhouse experiments, creeping bentgrass discoloration from bispyribac-sodium was exacerbated by reductions in mowing height from 24 to 3 mm, but mowing height did not influence clipping yields or root weight. In field experiments, discoloration of creeping bentgrass putting greens was greatest from applications of 37 g/ha every 10 d, compared to 74, 111, or 222 g/ha applied less frequently. Chelated iron effectively reduced discoloration of creeping bentgrass putting greens from bispyribac-sodium while trinexapac-ethyl inconsistently reduced these effects. Overall, creeping bentgrass putting greens appear more sensitive to bispyribac-sodium than higher mowed turf, but chelated iron and trinexapac-ethyl could reduce discoloration.

scholarly journals Creeping Bentgrass Quality following Preemergence and Postemergence Herbicide Applications

HortScience ◽  
1994 ◽  
Vol 29 (8) ◽  
pp. 880-883 ◽  
Author(s):  
B. Jack Johnson
Keyword(s):  
Field Experiments ◽  
Creeping Bentgrass ◽  
Monosodium Salt ◽  
Putting Green ◽  
Methylarsonic Acid ◽  
Turfgrass Quality ◽  
June July ◽  
Postemergence Herbicides ◽  
Quinolinecarboxylic Acid

Three field experiments were conducted to determine if several preemergence and postemergence herbicides were safe to apply to creeping bentgrass (Agrostis stolonifera L. `Penncross') maintained at putting green height. When dithiopyr was applied at preemergence in late February or early March, the emulsifiable concentrate formulation (≤1.7 kg·ha-1) and granular formulation (≤1.1 kg·ha-1) did not reduce the quality or cover of creeping bentgrass. Applied at preemergence, bensulide plus oxadiazon at 6.7 + 1.7 kg·ha-1 and 13.4 + 3.4 kg·ha-1 reduced turfgrass quality for 2 to 3 weeks and 8 weeks after treatment, respectively. When MON 12051 and monosodium salt of methylarsonic acid (MSMA) (≤0.14 and ≤2.2 kg·ha-1, respectively) were applied at postemergence to creeping bentgrass in early June, the reduction in turfgrass quality varied from slight to moderate for 1 to 2 weeks, but turfgrass fully recovered with no effect on turfgrass cover. Quinclorac applied at postemergence in early June at ≥0.6 kg·ha-1 severely reduced creeping bentgrass quality and cover for ≥8 weeks. Diclofop at 0.6 kg·ha-1 applied to creeping bentgrass in June, July, or August maintained consistently higher quality and cover ratings than when applied at ≥1.1 kg·ha-1. Diclofop applied at 0.6 kg·ha-1 in June and repeated at the same rate in July reduced quality of creeping bentgrass less than when applied at 1.1 kg·ha-1 at any date. Chemical names used: O,O-bis (1-methylethyl) S-{2-[(phenylsulfonyl)amino]ethyl} phosphorodithioate (bensulide); (±)-2-[4-(2,4-dichlorophenoxy)phenoxy]propanoic acid (diclofop); S,S-dimethyl-2-(difluoromethyl)-4-(2-methylpropyl)-6-(trifluoromethyl)-3,5-pyridinedicarbothioate (dithiopyr); methyl-5-{[(4,6-dimethoxy-2-pyrimidinyl)amino] carbonylaminosulfonyl}-3-chloro-1-methyl-1-H-pyrazol-4-carboxylate (MON 12051); 3-[2,4-dicloro-5-(1-methylethoxy)phenyl]-5-(1,1-dimethylethyl)-1,3,4-oxadiazol-2-(3H)-one (oxadiazon); 3,7-dicloro-8-quinolinecarboxylic acid (quinclorac).

Ethephon and Trinexapac-ethyl Influence Creeping Bentgrass Growth, Quality, and Putting Green Performance

2006 ◽  
Vol 3 (1) ◽  
pp. 0 ◽  
Author(s):  
Patrick E. McCullough ◽  
Haibo Liu ◽  
Lambert B. McCarty ◽  
Joe E. Toler
Keyword(s):  
Creeping Bentgrass ◽  
Green Performance ◽  
Putting Green ◽  
Growth Quality

Investigating low-dose herbicide programs for goosegrass (Eleusine indica) and smooth crabgrass (Digitaria ischaemum) control on creeping bentgrass greens

2021 ◽  
pp. 1-21
Author(s):  
John R. Brewer ◽  
Shawn D. Askew
Keyword(s):  
Low Dose ◽  
Field Experiments ◽  
Creeping Bentgrass ◽  
Putting Greens ◽  
Eleusine Indica ◽  
Golf Putting ◽  
Putting Green ◽  
Repeated Use ◽  
Herbicide Programs ◽  
Residual Control

Abstract Only four herbicides are registered for smooth crabgrass or goosegrass control on creeping bentgrass golf putting greens. None of the four herbicides control weedy grasses for the entire season or control weeds postemergence when applied once at labeled rates. Three of these have product labels that prohibit repeated use or application during stressful summer conditions. We hypothesized frequently applying herbicides at low doses could provide season-long control of summer grasses while minimizing turf injury. Seven field experiments were conducted on creeping bentgrass putting greens to evaluate various herbicides applied monthly, biweekly, or weekly for postemergence and residual control of goosegrass and smooth crabgrass as well as creeping bentgrass putting green tolerance. Metamifop applied twice monthly at 200 g ai ha−1, topramezone applied eight times weekly at 1.5 g ae ha−1, and siduron applied weekly at 5.6 kg ai ha−1 or four times biweekly at 11 kg ha−1 did not injure creeping bentgrass greater than 10% and maintained creeping bentgrass quality and cover equivalent to nontreated turf. Weekly or biweekly programs of fenoxaprop or quinclorac caused unacceptable injury and quality decline. Metamifop applied monthly and either fenoxaprop program controlled both smooth crabgrass and goosegrass 97 to 99% throughout the growing season. Programs containing either quinclorac or siduron controlled smooth crabgrass 99 to 100% but did not control goosegrass greater than 39%. All topramezone programs controlled smooth crabgrass 69 to 77% and goosegrass 93 to 98%. In additional studies, siduron applied five times biweekly did not injure creeping bentgrass putting greens and controlled smooth crabgrass greater than 90% at seasonal, cumulative rates between 17 and 65 kg ai ha−1. This method of frequent, low-dose herbicide treatment to control smooth crabgrass and goosegrass on golf putting greens is novel and could be legally implemented currently with siduron.

scholarly journals ‘L-93’ Creeping Bentgrass Putting Green Responses to Various Winter Light Intensities in the Southern Transition Zone

HortScience ◽  
2009 ◽  
Vol 44 (6) ◽  
pp. 1751-1756 ◽  
Author(s):  
Christian M. Baldwin ◽  
Haibo Liu ◽  
Lambert B. McCarty ◽  
Hong Luo ◽  
Joe E. Toler
Keyword(s):  
Transition Zone ◽  
Chlorophyll Concentration ◽  
Acid Ethyl Ester ◽  
Creeping Bentgrass ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Full Sunlight ◽  
Putting Green ◽  
Soil Temperatures ◽  
The Impact

Seasonal variations in temperature and solar radiation in the warm climatic region of the transition zone increase difficulty of creeping bentgrass [Agrostis stolonifera var. palustris (Huds.)] management throughout the year. The impact of winter shade on bentgrass quality and subsequent residual effects of winter shade in spring and summer months has not been investigated. Therefore, a 2-year field study investigated trinexapac-ethyl (TE) [4-(cyclopropyl-α-hydroxy-methylene)-3,5-dioxy-cyclohexanecarboxylic acid ethyl ester] as a winter management strategy to alleviate winter shade stress and determined the winter shade tolerance of ‘L-93’ creeping bentgrass under various reduced light environments. Treatments included a full-sunlight control; 58% and 96% morning, afternoon, and full-day shade artificial; and TE (0.02 kg a.i./ha) applied every 2 weeks from December to July. Data collection included daily light measurements (photosynthetic photon flux density), monthly canopy and soil temperatures, visual turfgrass quality (TQ), chlorophyll concentration, clipping yield, total root biomass, and total root nonstructural carbohydrates. Under 96% shade, canopy temperatures were reduced ≈57% from December to February, whereas soil temperatures were reduced 39% in February compared with full sunlight. Afternoon shade (58%) maintained acceptable TQ throughout winter for both years. Applying TE every 2 weeks in the winter negatively impacted bentgrass quality; however, TE enhanced spring and summer quality. Morning or afternoon shade minimally impacted parameters measured. Overall, moderate winter shade may not limit ‘L-93’ creeping bentgrass performance as a putting green in the transition zone. Results suggest winter shade does not contribute to creeping bentgrass summer decline because all shade-treated plots fully recovered from shade damage in spring months.

scholarly journals Impact of Nitrogen Source and Trinexapac-ethyl Application on Creeping Bentgrass (Agrostis stolonifera L.) Physiology under Neutral Shade, Deciduous Tree Shade, and Full Sunlit Conditions

HortScience ◽  
2012 ◽  
Vol 47 (7) ◽  
pp. 936-942 ◽  
Author(s):  
Edward J. Nangle ◽  
David S. Gardner ◽  
James D. Metzger ◽  
John R. Street ◽  
T. Karl Danneberger
Keyword(s):  
Soluble Sugars ◽  
Canopy Cover ◽  
Leaf Tissue ◽  
Acid Ethyl Ester ◽  
Creeping Bentgrass ◽  
Agrostis Stolonifera ◽  
Deciduous Tree ◽  
Soluble Carbohydrates ◽  
Nitrogen Treatments ◽  
Cyclohexane Carboxylic Acid

Decreased light quantity or quality affects the growth of turfgrass plants. Shade causes thinning of turfgrass stands and loss in surface quality. Plant changes include increased chlorophyll levels, lower soluble sugars, and loss of canopy cover. The objective of this research was to investigate if applications of foliar nitrogen and trinexapac-ethyl [4-(cyclopropyl-α-hydroxy-methylene)-3,5-dioxo-cyclohexane carboxylic acid ethyl ester] (TE) would result in beneficial biochemical changes in creeping bentgrass (Agrostis stolonifera L. cv. Penncross) grown in different shaded environments. Foliar applications of three nitrogen treatments, (NH2)2CO, Ca(NO3)2, or (NH4)2SO4, were made weekly at 0.43 g N/m2. Growth regulator treatments consisted of an untreated control or TE applied biweekly at an a.i. rate of 0.057 kg·ha−1. Plots were established in full sun (FS), neutral shade (NS), and deciduous shade (DS). Chlorophyll content, soluble carbohydrates, flavonoids, clipping yield, and color were measured. Nitrogen treatments caused some variation in levels of soluble carbohydrates in shaded conditions. Chlorophyll (Chl) levels varied between TE treatments, with increased levels of chlorophyll b (Chl b) found in TE-treated plots under FS. Application of TE resulted in higher flavonoid concentrations in leaf tissue in shaded conditions. Repeated applications of (NH2)2CO significantly improved color (P = 0.05). Turfgrass managers maintaining creeping bentgrass in shade may benefit from applications of TE and (NH2)2CO.

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