bluuebunny/crossref_metadata_2025 huggingface dataset:
Performance of Annual and Perennial Ryegrass Mixtures for Winter Overseeding into Three Warm‐Season Turfgrass Species
Authors: Fontanier Charles , Steinke Kurt
Published: October 2017

Perennial ryegrass (Lolium perenne L.) is commonly overseeded into warm‐season turfgrasses during the fall to create a temporary, actively growing green cover. Excessive persistence of perennial ryegrass cultivars can increase management inputs and prolong the spring transitional period. A 2‐yr field study was conducted to investigate the effects of three ryegrass overseeding treatments on winter turf performance and spring transition rate for three warm‐season turfgrasses maintained at a golf fairway height. Treatments included improved turf‐type annual (Lolium multiflorum Lam. ‘Panterra’) and perennial ryegrasses (‘Premier II’ and ‘Peak’) sown into ‘Tifway’ hybrid bermudagrass [Cynodon dactylon (L.) Pers. × C. transvaalensis Burtt Davy], ‘Cavalier’ zoysiagrass (Zoysia spp. Willd.), or ‘Sea Isle 1’ seashore paspalum (Paspalum vaginatum Sw.). Visual assessments of turf quality were performed throughout the spring and early summer. Warm‐season and cool‐season plant density was assessed by measuring shoot counts, aboveground dry weight, and light entering the canopy each May and July. Annual ryegrass alone or within a perennial ryegrass mixture provided acceptable winter turf quality and hastened spring transition but did not consistently improve warm‐season turf recovery over perennial ryegrass alone in bermudagrass or seashore paspalum. Overseeding zoysiagrass resulted in unacceptable turf quality during the summer, regardless of overseeding treatment. In general, warm‐season turfgrass overseeding potential, as defined by spring transition and summer recovery, was ranked as follows: seashore paspalum > bermudagrass > zoysiagrass.
Effects of Phosphorous Acid Compounds on the Incidence of Rhizoctonia solani in Tall Fescue and Creeping Bentgrass
Authors: Lee David J. , Tredway Lane P. , Shew H. David , Peacock Charles H.
Published: October 2017

Phosphorous acid‐containing compounds have been shown to be effective in controlling certain fungal pathogens. The objective of this study was to evaluate the effectiveness of the active ingredient of phosphorous acid (phosphite) in vitro and in vivo. One isolate each of Rhizoctonia solani AG 1, R. solani AG 2–2IIIB, Rhizoctonia zeae, and Pythium aphanidermatum were obtained from turfgrasses and assayed for sensitivity to phosphorous acid and the fungicides fosetyl‐Al, azoxystrobin, and azoxystrobin amended with salicylhydroxamic acid (SHAM). Six concentrations of each compound (0.01–10 mg L−1) were established in 9‐cm diameter Petri dishes. Radial growth of the colonies on the amended agar was measured to determine the relative growth of colonies compared with the growth of the colonies on unamended medium. Parallel greenhouse and field studies were initiated to determine the effects of phosphorous acid on disease incidence and overall turf quality. Mean 50% effective concentrations were observed for all four pathogens with the azoxystrobin amended with SHAM treatment. Effective concentrations for the 2–2IIIB, AG1, P. aphanidermatum, and R. zeae were 1.27, 0.04, 0.012, and 0.145 mg L−1, respectively. Azoxystrobin alone did not reduce colony growth by 50% in the 2–2IIIB and R. zeae isolate. Greenhouse and field studies showed differences (p < 0.05) between two phosphorous acid rates, turf quality, and disease incidence of R. solani in tall fescue (Festuca arundinacea Schreb.) and creeping bentgrass (Agrostis stolonifera L.) turf and the control. However, disease incidence was at an unacceptable level in the phosphorous acid treatments. Phosphorous acid applications did increase the elemental phosphorus composition of shoot tissue.
Evaluation of Herbicides and their Tank‐Mixes for Suppression of Bermudagrass in Zoysiagrass
Authors: Patton Aaron J. , Trappe Jon M. , Doroh Mark C. , McElroy J. Scott
Published: October 2017

Zoysiagrass (Zoysiaspp.) is a popular turfgrass species for use on lawns, sod farms, and golf courses in the transitional and southern climatic zones of the United States. One common problem in managing zoysiagrass is the contamination and subsequent removal of bermudagrass (Cynodonspp.). Various herbicides and herbicide tank‐mixes may be utilized for bermudagrass control in zoysiagrass. Research was conducted in Fayetteville, AR, and Auburn, AL, to evaluate aminocyclopyrachlor, fluazifop, fenoxaprop, triclopyr, and their combinations for bermudagrass suppression in zoysiagrass. Fluazifop at 0.105 kg active ingredient (a.i.) ha–1suppressed bermudagrass most, but this application caused unacceptable injury and quality reduction to zoysiagrass. Tank‐mixing fluazifop or fenoxaprop at 0.14 kg ai ha–1with triclopyr at 0.56 kg acid equivalent (a.e.) ha–1reduced zoysiagrass injury and improved turf quality over fluazifop or fenoxaprop alone. Fluazifop + triclopyr provided more bermudagrass suppression than fenoxaprop + triclopyr. Aminocyclopyrachlor (0.026 or 0.071 kg a.e. ha–1) did not reduce herbicide injury from fluazifop or fenoxaprop applications to zoysiagrass and did not provide significant bermudagrass suppression. Results suggest that fluazifop + triclopyr and fenoxaprop + triclopyr remain the best treatments for bermudagrass suppression in zoysiagrass because they provide bermudagrass suppression without reducing zoysiagrass quality.
Annual Nitrogen Requirement of Bahiagrass Lawns Maintained in Subtropical Climates
Authors: McGroary Pauric , Shaddox Travis W. , Cisar John L. , Unruh J. Bryan , Trenholm Laurie E.
Published: October 2017

Current best management practices (BMPs) regarding the application of nitrogen (N) to bahiagrass (Paspalum notatum Flügge) in southern Florida are 98 to 196 kg ha−1 yr−1. This range has not been tested to determine if the range adequately produces quality bahiagrass without adversely contributing to nonpoint source additions of N to ground water. The objectives of this research were to determine the N necessary to support acceptable bahiagrass quality by measuring associated color, growth, and nitrate‐N (NO3–N) leaching. Research was conducted from October 2006 to October 2008 in Fort Lauderdale, FL. Nitrogen was applied in 60‐d cycles at rates of 49, 98, 196, or 294 kg ha−1 yr−1 under two irrigation regimes (2.5 mm d−1 and 13 mm three times weekly). Bahiagrass quality and color was acceptable under each N rate during each cycle and regression indicated application of N to bahiagrass was not necessary to produce acceptable turfgrass. Nitrate‐N leaching was unaffected by N rates during each cycle except during Cycle 3 of 2008 when the 196 and 294 kg ha−1 yr−1 led to 93 and 94% greater leaching, respectively, than the 49 kg ha−1 yr−1. The high‐irrigation regime increased NO3–N leaching by as much as eightfold but was not consistent among cycles. If current N recommendations were revised downward (∼49 kg ha−1 yr−1), bahiagrass quality would remain acceptable and the risk of NO3–N leaching would be reduced.
Multifunctional Golf Facilities as a Resource of Important Ecosystem Services in a Changing Urban Environment: Nordic Case Studies
Authors: Dahl Jensen Anne Mette , Caspersen Ole Hjorth , Jensen Frank Søndergaard , Strandberg Maria
Published: October 2017

Multifunctional golf facilities are a resource of important ecosystem services in a changing urban environment. Several examples of multifunctional activities fulfilling environmental quality goals are available on Nordic golf courses. These examples should set the standard for many other peri‐urban golf courses. The handbook A Practical Guide to Assessing your Golf Course´s Multifunctional Potential (Jensen et al. 2015) is intended as a tool to visualize the multifunctional potential of golf facilities and to start the process of developing multifunctional values—for example, to contribute to the production or conservation of biological diversity, natural and cultural environments, and to the retention and expansion of ecosystem services in peri‐urban environments and the cultivated landscape. In this paper, we extract examples from Nordic multifunctional golf facilities and relate them to environmental quality goals.
Freezing Tolerance of Field‐ and Growth Chamber–Acclimated Zoysiagrass Hybrids
Authors: Wu Y. , Chandra A. , Genovesi A. D. , Meeks M.
Published: October 2017

The objective of this study was to test the freezing tolerance of a medium‐fine textured ecotype (DALZ 1301) of zoysiagrass (Zoysia spp.) and six fine‐textured interspecific hybrids (DALZ 1304–1309) derived from crosses between Z. minima (Colenso) Zoltov. or Z. pauciflora (Mez.) and Z. matrella (L.) Merr. after cold acclimation under field (FE‐1 and FE‐2) and controlled‐environment conditions (GC‐1 and GC‐2) in 2014 and 2015. Following acclimation, samples were subjected to six freezing treatments (–3, –5, –7, –9, –11, and –13°C) for 1 h, thawed, and placed under optimum greenhouse conditions for recovery. Greenup was visually rated on a 1 to 9 scale (1 = brown; 9 = completely green; 5 = acceptable) at 5 wk. Lethal temperatures (LT50) for each genotype were determined by nonlinear regression. Mean LT50 for field‐acclimated samples ranged from –5.5°C (DALZ 1307) to –9.3°C (Meyer). Mean LT50 for controlled‐acclimation samples ranged from –1.6°C (DALZ 1304) to –9.9°C (Meyer) in GC‐1 and from –4.8°C (DALZ 1304) to –9.4°C (Meyer) for GC‐2. The LT50 of DALZ 1301 and Meyer were statistically similar, but interspecific hybrids were less freeze tolerant than Meyer. Results suggest a limited potential of Z. minima, Z. pauciflora, and Z. matrella lines to impart freezing tolerance. Additionally, high correlations (R2 = 0.718–0.767) of lethal temperatures with field and controlled acclimation experiments, suggest controlled‐environment acclimation is suitable for testing freezing tolerance in zoysia.
Hormone and Dehydrin Expression Responses to Cold Acclimation in Two Zoysiagrass Cultivars with Contrasting Freezing Tolerance
Authors: Zhang Xunzhong , Shang Chao , Liu Yiming , Hu Guofu , Harich Kim , Ervin Erik H.
Published: October 2017

Zoysiagrass (Zoysia spp.), a warm‐season turfgrass genus, is subjected to freezing damage in the US transition zone and other similar climate regions. This study was designed to investigate changes in hormones and dehydrin expression in responses to cold acclimation (CA) in two zoysiagrass cultivars. Two zoysiagrass cultivars (‘Meyer’, cold tolerant; ‘Cavalier’, relatively cold sensitive) were subjected to either CA (8/4°C day/night and a photosynthetically active radiation of 250 μmol m−2 s−1 over a 10‐h photoperiod) or no CA in growth chambers for 28 d. Cold‐acclimated Meyer had greater overall freezing tolerance (stolon temperature resulting in 50% survival [LT50] = −15.4°C) than cold‐acclimated Cavalier (stolon LT50 = −8.2°C). Leaf abscisic acid (ABA) content increased and cytokinins (trans‐zeatin riboside and isopentenyl adenosine) declined during CA. Cold‐acclimated Meyer accumulated higher levels of ABA but less cytokinins relative to cold‐acclimated Cavalier. Leaf ABA content was 37% higher in cold‐acclimated Meyer than in cold‐acclimated Cavalier at 28 d. Meyer had higher levels of indole‐3‐acetic acid than Cavalier. Cold acclimation induced dehydrin (12, 23, and 65 kDa) expression in leaf tissues of both cultivars. Cold‐acclimated Meyer had greater abundance of the dehydrins (12, 23, 30, and 35 kDa) in stolon tissues and in leaf tissues (12, 30, and 65 kDa) than cold‐acclimated Cavalier. The results of this study suggest that higher levels of ABA and certain dehydrin expression and lower levels of cytokinins during CA may be associated with freezing tolerance in zoysiagrass.
Dissipation of Foliar Carfentrazone Residues after Application to a Tall Fescue Lawn and Implications for Human Exposure
Authors: Cooper R. J. , Shea D. , Gannon T. W. , Peacock C. H. , John C. V.
Published: October 2017

Dislodgeable foliar residues (DFR) are a primary route for human exposure after pesticide application to turfgrass areas. The portion of applied pesticide available for human exposure via dislodgeable residues depends on various factors. In this study, DFR were determined over a 15‐d period after carfentrazone application to an established stand of ‘Confederate’ tall fescue (Festuca arundinacea Schreb). Dislodgeable foliar residues were determined by wiping treated turfgrass with a distilled‐water‐dampened cheesecloth and analyzing samples using gas chromatography–mass spectrometry. Less than 20% of the applied carfentrazone (18,000 ng dm−2) was dislodged, with 13.8% dislodged immediately after application. Dislodgeable foliar residues as determined 1, 4, and 8 h after treatment contributed an additional 5.5% to the applied carfentrazone dislodged from tall fescue foliage. One day after treatment (DAT), carfentrazone dislodgeable residue levels had declined to below 1% of that applied and were nondetectable 3 DAT and after. Carfentrazone residues resulted in a maximum estimated hazard quotient <1 for the duration of the study, indicating that potential human toxicological effects associated with maximum field residue levels are unlikely. This work indicates that carfentrazone poses minimal risk to human health via dermal exposure applied per label recommendations.
Effect of Oriental Mustard (Brassica juncea) Seed Meal for Control of Dollar Spot on Creeping Bentgrass (Agrostis stolonifera) Turf
Authors: Pan Xiaowei , Earlywine Daniel T. , Smeda Reid J. , Teuton Travis C. , English James T. , Sams Carl E. , Xiong Xi
Published: October 2017

This research evaluated oriental mustard [Brassica juncea (L.) Czern.] seed meal (MSM) for safety and efficacy in control of dollar spot (Sclerotinia homoeocarpa F.T. Benn.) in vitro and on creeping bentgrass (Agrostis stolonifera L.) turf. As a plant residual, MSM is the seed fraction that remains after seeds are crushed and oil is removed. The meal contains both nitrogen and secondary compounds termed glucosinolates. When moist, glucosinolates convert to fungicidal isothiocyanates. The in vitro study determined that MSM at higher rates completely suppressed S. homoeocarpa mycelial growth. A field study was conducted for 2 yr with three sequential applications of MSM at seven rates ranging from 0 to 1680 kg ha−1, in addition to the fungicide iprodione at 3.1 kg a.i. ha−1. In 2007, the severity of dollar spot infections varied among MSM treatments, with greater rates reducing dollar spot up to 82% compared with untreated control. In 2008, MSM at 1680 kg ha−1 reduced dollar spot by 60% or greater 8 to 14 wk after initial application (WAIA). After application of MSM at 1120 kg ha−1 or greater, the color of creeping bentgrass color was reduced 1 point on a 1 to 9 scale, but this reduction in color only lasted for 2 wk, and turf color in treated plots increased significantly by 6 WAIA compared with the untreated plots. Collectively, our results suggest that MSM is an organic material that could be integrated into a dollar spot management program on turf for minimizing selection of pathogen resistance to fungicides.
Efficiency of Embryo Rescue Technology in St. Augustinegrass Breeding
Authors: Genovesi A. D. , Chandra A. , Meeks M.
Published: October 2017

St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] is a popular warm‐season turfgrass in Gulf Coast regions of the United States. Diploid St. Augustinegrass produces fertile seed, but triploids and higher polyploids are mostly sterile. Polyploid St. Augustinegrass cultivars have been selected for their resistance to southern chinch bugs, St. Augustine Decline, and drought tolerance but lack the cold hardiness and shade tolerance of diploids. However, because of sterility barriers, the polyploid germplasm had not been fully used as breeding material until 2009 when we reported the development of interploid hybrids using embryo rescue technology. The objective of the present study was to backcross these first‐generation interploid hybrids with diploid males to produce second‐generation hybrids. Sterility barriers were found to be much greater with second‐generation crosses yielding only 0.00 to 2.69% progeny per interploid hybrid. Using this technique, the embryos are generally rescued 3 wk postpollination, thereby causing a heavy demand on one's time to process spikelets before embryos abort. Our preliminary findings show the use of cold storage at 7°C to potentially extend the processing period up to 2 mo with a slight drop off in efficiency (4.37–6.03% crossability). Our results also show the potential of first‐generation hybrids to exhibit superior performance under drought when compared with diploid cultivars Palmetto and Raleigh. Tested second‐generation interploids did not exhibit superior performance in drought. Nonetheless, our results emphasize the utility of embryo rescue technology in facilitating gene exchange between ploidy levels to generate hybrids with superior performance.
Bibliometric Analysis of the International Turfgrass Society Research Journal, Proceedings, and Supplements, 1969 to 2013
Authors: Cookingham P. O. , Schury M. , Mabie‐Flynn E. , Lundeen A.
Published: October 2017

A bibliometric description of the publications in the International Turfgrass Society Research Journal, Proceedings, and supplements from 1969 to 2013 provides a longitudinal view of authorship and paper trends. To date, there have been few bibliometric analyses of these publications or of turfgrass literature as a whole. Using the Turfgrass Information Center's Turfgrass Information File database, bibliometric metadata were examined for these 1685 unique papers to analyze paper length, number of authors, number of references, host countries, authors’ national affiliations, title words, section headings, content keywords, and rates of institutional collaboration. United States–affiliated authors wrote 67.5% (n = 1137) of all papers, more authors produced jointly written papers over time, and the growth of domestic institutional collaboration outpaced the growth of international collaboration. Overall, most content was focused on areas such as field trials, evaluations, and cultural and chemical maintenance practices rather than on specific industry sectors.
Damage Functions for Sting Nematode (Belonolaimus longicaudatus) on Bermudagrass Turf
Authors: Shaver Bradly R. , Agudelo Paula , Martin S. Bruce
Published: October 2017

Sting nematode (Belonolaimus longicaudatus) is one of the most aggressive and damaging parasites of bermudagrass, a widely used turfgrass in the southeastern United States. A damage threshold model for sting nematode on bermudagrass was developed with data collected during a 2‐yr field trial at multiple locations in South Carolina. Soil cores and visual turf quality ratings were collected on multiple sampling dates from plots at each location. Bermudagrass root weight and sting nematode density were determined for each core. A total of 678 soil cores were collected and used for root weight, turf quality, and nematode density regressions. Models discussed in this paper include linear and nonlinear regressions, a segmented regression model, and the first Seinhorst model for sting nematodes on bermudagrass. Results suggest reduced turfgrass quality is detectable before reductions in root weights are observed. Our findings support the use of low action–level thresholds for sting nematodes on bermudagrass, such as those applied in South Carolina (17 nematodes 100 cm–3 soil).
Tolerance of Bentgrass (Agrostis spp.) to Postemergence Applications of Metamifop
Authors: Cooper Tyler , Beck Leslie L. , Straw Chase M. , Henry Gerald M.
Published: October 2017

Previous research indicates that metamifop may be an alternative for the control of bermudagrass (Cynodon spp. Rich.) in bentgrass (Agrostis spp. L.) with minimal phytotoxicity; however, only a few cultivars have been evaluated for tolerance. We hypothesize that bentgrass cultivars will respond differently to increasing rates of metamifop. Therefore, the objective of our research was to evaluate the tolerance of several bentgrass cultivars to sequential postemergence applications of metamifop. ‘L‐93’, ‘Penn A‐4’, ‘Penncross’, ‘Seaside II’, ‘Crystal Bluelinks’, and ‘T‐1’ creeping bentgrass (Agrostis stolonifera L.) and ‘SR 7200’ velvet bentgrass (Agrostis canina L.) were established in a greenhouse and sprayed with metamifop at 0, 200, 300, 400, and 500 g a.i. ha−1. Metamifop applications reduced 3‐wk clipping production and increased phytotoxicity of L‐93, Penn A‐4, and Penncross more than Seaside II, Crystal Bluelinks, T‐1, and SR 7200 3 and 6 wk after initial treatment. Seaside II, Crystal Bluelinks, T‐1, and SR 7200 exhibited good tolerance (≤26% phytotoxicity) to sequential applications of metamifop at 300 g a.i. ha−1. The same applications caused ≥47% phytotoxicity to the remaining cultivars. However, methods employed in this research may have affected the level of bentgrass phytotoxicity. Plants grown under greenhouse conditions are often more susceptible to herbicides and therefore exhibit higher levels of phytotoxicity. Furthermore, continuous defoliation indicative of golf course putting greens may stimulate leaf production, thereby reducing bentgrass phytotoxicity associated with metamifop applications. Consequently, additional research is warranted to evaluate the response of bentgrass cultivars maintained under putting green conditions to field applications of metamifop.
Turfgrass Cover Sources Vary in Temperature, Light and Moisture Penetration, and Weight
Authors: Goatley Michael , Askew Whitnee , Askew Shawn , Dickerson Jonathan , McCall David
Published: October 2017

Turfgrass managers apply covers to manipulate grass and soil environments. This study evaluated how various cover compositions and colors affect winter temperatures under cover, light and moisture penetration, and wet and dry weights of covers in the field. Seven covers including interwoven translucent polyethylene, gray, white, or orange nonwoven geotextiles, black and white woven polypropylene, and aluminized high‐density polyethylene strips were tested in Blacksburg, VA. Covers were in place December to March of 2013–2014 and 2014–2015 to evaluate bermudagrass (Cynodon dactylon × transvaalensis Burtt‐Davy, ‘Patriot’) surface temperature moderation. Cover effects on photosynthetically active radiation (PAR), moisture penetration (measured as percent change in soil volumetric water content [%SVWC] at 5‐cm soil depth under cover prior to and following a minimum 1.25 cm rain event), as well as cover dry and wet weights in the field prior to and after 0.1 cm irrigation were collected in spring 2016. Considering mean minimum extreme low temperatures, all covers provided significantly higher temperatures than uncovered control in 2013–2014, while in 2014–2015 all covers except for interwoven translucent polythethylene and aluminized high‐density polyethylene strips exceeded the control. Of standard covers, translucent polyethylene had the highest PAR transmission and was always in the top statistical category for mean maximum and daily range temperatures. Orange geotextile had the greatest dry and wet weights and gray and orange geotextiles had the lowest change in %SVWC on a 3% sloped native soil. Understanding differences in cover parameters will aid turfgrass managers in appropriate cover selection.
Wetting Agent Influence on Putting Green Surface Firmness
Authors: Bauer Samuel J. , Cavanaugh Matthew J. , Horgan Brian P.
Published: October 2017

Soil wetting agents are commonly used in the golf course industry for managing soil moisture. Recently, there has been an interest in the influence wetting agents have on the firmness characteristics of putting surfaces. To date, there has been no established relationship between wetting agents and surface firmness of putting greens. Research was conducted in St. Paul, MN, to evaluate the surface firmness impacts from 13 commercially available wetting agents applied individually or in combination to a creeping bentgrass (Agrostis stolonifera L.) research green. Treatments were evaluated as season‐long wetting agent programs with applications every 4 wk. Data collection included surface firmness (Clegg Impact Soil Tester), turfgrass quality (TQ), chlorophyll index (CI), volumetric water content (VWC), and spring water drop penetration tests (WDPT) to assess residual of fall‐applied wetting agents. Firmness measurements were not affected by wetting agent applications in 2014. In 2015, Duplex (15% alcohol ethoxylates, 2% alkyl sulfonate, 7% ethylenediaminetetraacetic acid), Aquicare (100% blend of alkoxylated alcohols), and Primer Select (100% alkoxylated polyols) provided the firmest surfaces. Ratings for TQ and CI demonstrated only minor influence of wetting agent applications, as did VWC measurements. Spring WDPT tests indicated wetting agent residual from late‐fall applications, and persistence was most evident at shallow depths. Revolution (100% modified alkylated polyol) demonstrated the greatest residual, whereas Duplex and Aquiflo (45% poloxanlene, 2‐butoxyethanol, siloxane surfactants) had the least residual. These results indicate that firmness can be influenced by wetting agent applications, and that persistence in the soil through the winter months is possible.
Overexpression of Arabidopsis DREB1A Gene in Transgenic Poa pratensis: Impacts on Osmotic Adjustment and Hormone Metabolism under Drought
Authors: Xu Lixin , Li Feifei , Han Liebao , Song Guilong , Zhang Xunzhong
Published: October 2017

Drought stress is a major limiting factor in turfgrass management in many regions. The objective of this study was to examine responses of transgenic Kentucky bluegrass (Poa pratensis L.) overexpressing an Arabidopsis DREB1A gene to drought stress. Five transgenic Kentucky bluegrass (cv. Baron) lines overexpressing AtDREB1A and wild‐type (WT, nontransgenic plant) were subjected to water deficit for 12 d and then rewatering treatment for 3 d. Leaf relative water content (RWC), turf quality, electrolyte leakage (EL), osmoregulating compounds, abscisic acid (ABA), and indol‐3‐acetic acid (IAA) content were measured. Transgenic plants had higher RWC and turf quality and lower EL relative to WT plants during drought stress and recovery periods. In addition, the transgenic plants had greater osmotic adjustment associated with higher water‐soluble carbohydrates (WSC), proline, and soluble protein in leaf tissues. The transgenic plants had higher IAA and lower ABA content relative to WT plants. The results suggest that the improvement of drought tolerance in transgenic Kentucky bluegrass overexpressing the DREB1A gene may have resulted from increased accumulation of organic solutes (WSC, proline, and protein) and alteration in hormone metabolism.
12‐Year Study at Saitama Stadium 2OO2: The Relationship between Turf Quality and Rootzone Functions by Temperature‐Controlling System
Authors: Tonogi Hideaki , Wajima Masataka
Published: October 2017

A 12‐yr soccer pitch survey was performed at Saitama Stadium 2OO2 after opening for the Japan‐Korea World Cup in 2002. This survey lasted from 2002 to 2015 and measured traits such as ball rebound, ball roll, surface hardness, traction, ground surface hardness, grass height, infiltration rate, 50‐ and 100‐mm depth air permeability, and root length. Most notably, this paper reports on tensile strength data obtained using a new handy‐type device. This device will be useful to conduct future periodic surveys of soccer pitches easily and without expense.
Infilrooter: Multifunctional Apparatus to Measure Water Infiltration, Compaction, and Playability of Manicured Grass Sports Surfaces
Authors: Ross William R. , Ross Susanne M. , Ross Roderick
Published: October 2017

Compaction of manicured grass surfaces such as golf and bowling greens and tennis lawns is a progressive and inevitable process caused by high player numbers and maintenance machines. For the health of the grass, compaction can be minimized by timeous aeration techniques. The objective of this case study was to describe a benchmarking concept using water infiltration rate to assess surface compaction of sports turfs and consequently the need for aeration. A simplified and low‐cost apparatus, termed the Infilrooter, enabled both the measurement of water infiltration and subsequent withdrawal of a core sample for investigating the root‐soil‐grass systems. Both an infiltrometer and core sampler are well‐known concepts, but their functional combination, as in the Infilrooter, is novel and has no known previous application in grass management to assess compaction. A suitable range of infiltration rates between 100 and 1000 mm h−1 was observed on healthy manicured grass sports surfaces. Infiltration rates <100 mm h−1 were indicative of surface compaction and poor root development. A corollary to the Infilrooter case study established the relationship between water infiltration rate and stimpmeter readings (speed of green) as a useful index to gauge the playability of grass sports surfaces.
Incidence and Distribution of Mite Species across a Reference Collection of Cynodon spp. (Bermudagrass) Genotypes Growing in Subtropical Australia
Authors: Loch Donald S. , Seeman Owen D.
Published: October 2017

In November 2014, unreplicated plots of 43 different cultivars and experimental genotypes of Cynodon spp. (bermudagrass) from a 14‐yr‐old turfgrass collection (growing at Cleveland, Queensland, Australia) were rated for mite damage. The phytophagous mite species present, Aceria cynodoniensis (Eriophyidae) and/or Dolichotetranychus australianus (Tenuipalpidae), was initially assessed from the characteristic symptoms caused by each species. Samples taken from 55% of the 29 visually infested genotypes confirmed the diagnoses based on symptoms of the sole or dominant‐mite species present. The data provide a snapshot of infestation by two mite species across a wide range of bermudagrass genotypes at a point in time. The implications of the results are discussed in relation to differential susceptibility of varieties and varietal families to one or other of these mite species, with reference to other records of mite species found in named bermudagrass varieties sampled elsewhere in Australia over the period 2010 to 2017.
Estimating Transpiration from Turfgrass Using Stomatal Conductance Values Derived from Infrared Thermometry
Authors: Peterson K. W. , Bremer D. J. , Blonquist J. M.
Published: October 2017

Infrared thermometry provides accurate measurements of plant canopy temperature, which, along with basic weather variables, allows estimation of canopy stomatal conductance to water vapor flux (gc) and transpiration. Our objectives were (i) to compare single‐ versus two‐source energy balance approaches for sensible and latent heat flux calculations; (ii) to use gc calculated with the method of Blonquist et al. (2009) to estimate transpiration from a dense, well‐watered sward of tall fescue (Festuca arundinacea Schreb.) turfgrass; and (iii) to compare calculated canopy transpiration with measured lysimeter evapotranspiration (LYSET). The study was conducted from June to October 2012 near Manhattan, KS. Three microlysimeters containing ambient cores of turfgrass were used to measure LYSET. Four infrared radiometers, used to measure canopy temperature, were positioned on a weather station that recorded all data necessary for calculating gc. Transpiration calculated from modeled gc averaged 1.71 mm d−1 (29.6%) less than mean LYSET, suggesting 29.6% of LYSET was from soil water evaporation. Nighttime LYSET may have inadvertently contributed to the soil water evaporation component using this method (our conductance model assumed zero nighttime transpiration). Differences were negligible between the single‐ and two‐source energy balance approaches for sensible and latent heat flux calculations. Results indicate transpiration may be reliably estimated via calculation of gc in turfgrass.
Breeding Cool‐Season Turfgrass Cultivars for Stress Tolerance and Sustainability in a Changing Environment
Authors: Meyer William A. , Hoffman Lindsey , Bonos Stacy A.
Published: October 2017

Growth and sustainability of cool‐season turfgrass species has the potential to be negatively impacted by future climate change; therefore, it will be necessary to breed turfgrass cultivars that have improved abiotic and biotic stress tolerance compared with cultivars that are currently available. This will require the use of techniques that can efficiently and effectively identify novel germplasm for incorporation into a breeding program. Over the past decade, advances have been made in the methodologies used to develop new cultivars of apomictic and open‐pollinated, cool‐season turfgrass species. This keynote address will discuss the impact climate change will have on plant breeding objectives, breeding techniques used by Rutgers University, and advances that have been made in breeding cool‐season grasses for improved abiotic and biotic stress tolerance.
Sodium Chloride Transport in the Stolons of Zoysia matrella in a Heterogeneous Saline Environment
Authors: Sugiura Souichirou , Tanaka Satoru , Mizuniwa Chizuko , Takahashi Shimpei
Published: October 2017

Zoysia matrella Merr. can tolerate salt. However, nothing is known about NaCl transport in the stolon between ramets. We examined how much NaCl is transported to other ramets via the stolons to enhance understanding of the salt tolerance mechanisms from the perspective of physiological integration. In this study, interconnected clonal stolon ramets were grown in three separate pots (basal [BR], intermediate [IR], and apical ramets [AR]), such that the stolons were not touching the soil (SNTS). The study was conducted in two experimental plots: (A) all ramets were irrigated with tap water (control), and (B) IR was irrigated with NaCl solution, while BR and AR were irrigated with tap water (NaCl application in IR). For the IR irrigated with NaCl solution, the leaves, stolons, and roots had higher Na+ and Cl− concentrations than those of the ramets irrigated with tap water. In comparisons of BR and AR, there were no significant differences in the Na+ or Cl− contents of each part of the ramet, compared with plants irrigated with tap water. In the SNTS irrigated with NaCl solution, the leaves and stolons contained more Na+ and Cl− than those irrigated with tap water. From these results, it was found that until a stolon node touches the ground and develops roots, Na+ and Cl− are transported through the stolon. However, for interconnected ramets under heterogeneous saline conditions, there are two hypotheses: NaCl might be diluted with water in BR and AR, or NaCl is not transported from IR to either BR or AR after ramets are established.
Herbicide Screening Trials on Earthquake Damaged Leptinella maniototo Bowling Greens
Authors: Walmsley William H , Stewart Alan V
Published: October 2017

Lawn bowls in New Zealand is played on a native herb in the Asteraceae family, Leptinella maniototo (Petrie). Only three herbicides are currently recommended for postemergence broadleaf weed control in Leptinella maniototo greens by the New Zealand Sports Turf Institute. After the Christchurch earthquakes of 2010 and 2011, a number of abandoned bowling greens were available for trials. Nine trials were performed on five greens screening 51 active ingredients or mixtures. The first eight nonreplicated screening trials used a single‐nozzle sprayer fitted with a TeeJet even flat nozzle adjusted to 0.5‐m width spraying strips 5 to 6 m long. The eighth trial used two replicates and a four‐nozzle boom sprayer. The trials were scored at two weekly intervals on a 1‐to‐9 scale, where 9 = no visible effect. Thirteen active ingredients caused no visible discoloration or growth reduction. Four active ingredients caused discoloration for a single scoring, which may be acceptable. The active ingredients with most potential for broadleaf weed control are trifluralin, nicosulfuron, chlorsulfuron, carfentrazone‐ethyl, oxyfluorfen, and thifensulfuron‐methyl. Preemergence herbicides with acceptable safety are dimethenamid, oryzalin, oxadiazon, chlorpropham, propachlor, and chloridazon. Grass control herbicides are clethodim, fluazifop‐P butyl, and haloxyfop.
A Life‐Cycle Cost Analysis of Synthetic Infill and Natural Grass Systems
Authors: Daviscourt Brian L. , Kowalewski Alec R. , Lambrinos John G. , Eleveld Bartelt
Published: October 2017

The perception of a long‐term cost advantage of synthetic infill turf systems relative to natural grass systems has contributed to a rise in their popularity in the United States. This case study compared the costs associated with installation and maintenance of third‐generation synthetic infill and natural turfgrass systems in the US Pacific Northwest. Installation costs, maintenance budgets, and field use information were gathered from five synthetic and five natural grass systems and used to find the cost of providing an hour of use. Costs were inflated by 3% each year and brought back to their present value with a 4% discount rate. For maintenance and replacement scenarios with different planning lives (i.e., 16 vs. 20 yr), net present values were converted to annual equivalents by amortizing the net present values into an annual equivalent payment using the discount rate. Findings from this work determined that the average cost of installing a synthetic field was US$163.00 m−2 and the average annual equivalent was $20.10 m−2. The average cost of installing a natural grass field was $45.60 m−2 and an annual equivalent $10.10 m−2. When the cost of providing an hour of use was taken into consideration, the synthetic fields averaged $3.30 per player use hour, and natural grass fields averaged $3.50 per player use hour.
Ploidy Characterization of Axonopus by Meiotic Chromosome Counts and Flow Cytometry
Authors: Quesenberry K. H. , Kenworthy K. E. , Harrison D.
Published: October 2017

Carpetgrasses (Axonopus spp.) have been used as home lawn, sports, and amenity turfgrasses in many locations around the world. Only limited efforts have focused on genetic improvement of Axonopus for turf. Before initiating any genetic improvement program, knowledge of ploidy differences within and among species in a germplasm collection is critical. We evaluated the ploidy variability in Axonopus compressus (Sw.) P. Beauv, Axonopus furcatus (Flüggé) Hitchc., and Axonopus fissifolius (Raddi) Kuhlm. using flow cytometry and meiotic chromosome counts. Meiotic chromosome observations combined with flow cytometry histograms results show that, within our collection, all genotypes of A. compressus were 2n = 4x = 40, one genotype of A. furcatus was 2n = 4x = 40, and all genotypes of A. fissifolius were 2n = 8x = 80 chromosomes. Although a detailed meiotic analysis was not conducted, photographic evidence supports the finding that meiosis, even in the high‐chromosome‐number A. fissifolius, was regular with very few cytological aberrations.
Zoysiagrass Use and Culture in Europe
Authors: Magni Simone , Pompeiano Antonio , Volterrani Marco
Published: October 2017

In Europe, the cultivation of warm‐season turfgrasses was negligible until the beginning of the 1990s. A scientific approach to their cultivation started with field trials being installed in several locations in Italy in 1994, when adaptation to climatic conditions and first screening of relative performance of cultivars was done to assist turf growers in introducing zoysiagrass (Zoysia spp. Willd.) species and cultivars in the warm temperate regions of Mediterranean Europe. At a later stage, studies on zoysiagrass adaptation were extended to winter dormancy and techniques to extend color retention. Research work has also been performed to explore the application of zoysiagrass for soccer pitches and green roofs. Despite the increasing availability of research‐based knowledge regarding the adaptation and cultivation of zoysiagrass, its usage in European countries is still limited.
Divot Resistance of Thick Cut Sod as Influenced by Preharvest Nitrogen and Sand Topdressing
Authors: Mascitti Evan C. , McNitt Andrew S. , Serensits Thomas J.
Published: October 2017

Professional sports facilities in the United States install thick‐cut sod during the playing season. Field performance immediately after installation is primarily determined by maintenance practices at the sod farm. This research investigated the influence of six N programs (98–245 kg N ha−1 yr−1 applied in spring or fall) and two sand‐topdressing rates (0 and 8.5 kg m−2 yr−1) on Kentucky bluegrass (KBG, Poa pratensis L.). In 2013 and 2014, KBG was established from seed in September and grown for 7 mo at a commercial sod farm (Hammonton, NJ) and then transported as sod and grown for another 7 mo under six by two treatment combinations at University Park, PA. Sod was harvested 14 mo after seeding and evaluated for divot resistance, shear, and sod strength. In 2013, all N treatments were similar in divot resistance except the 245‐kg total N rate, which exhibited the lowest divot resistance. In 2014, the most divot resistance was observed with 49 kg N ha−1 applied three times in the spring (147 kg total N) or using the same N program with another 49 kg ha−1 applied in September (196 kg total N). Nitrogen treatments resulted in few meaningful differences in shear resistance. Sand topdressing affected divot and shear resistance differently. Topdressing reduced divot resistance by only 6% in 2014 and had no effect in 2013. Topdressing reduced shear resistance by averages of 21.6 and 28.4% in 2013 and 2014, respectively. Growers may improve the divot resistance of KBG sod by moderating N inputs.
Cultivation Reduces Infestation of Silvery‐Thread Moss in a Creeping Bentgrass Putting Green
Authors: Raudenbush Zane , Keeley Steven J.
Published: October 2017

Cultivation creates voids in a putting green that may be recolonized by weeds or creeping bentgrass (Agrostis stolonifera L.); therefore, we investigated the cumulative effect of cultivation on a silvery‐thread moss (STM, Bryum argenteum Hedw.) infestation in a creeping bentgrass putting green when used with or without light, frequent topdressing, and the herbicide carfentrazone. Cultivation treatments were applied for 2 yr in the spring and fall and included hollow‐tine aerification at low and high surface disruption (SD), vertislicing, and no cultivation. Carfentrazone was applied 1 wk before and after cultivation treatments each spring and fall. On average, each split application of carfentrazone reduced STM cover by ∼20%. Cultivation did not increase STM cover; to the contrary, hollow‐tine aerification at low SD and vertislicing slightly reduced STM cover, even in the absence of carfentrazone. Topdressing did not affect STM cover. The greatest reduction in STM cover was achieved when cultivation treatments were used in conjunction with carfentrazone.
The Commons Revisited: Revalorizing the Role of comuneiros in the Redesign of Urban Agro‐Food and Agroforestry Systems
Authors: Dominguez Garcia M. Dolores , Swagemakers Paul , Schmid Otto
Published: October 2017

Continuing urbanization means that city regions face challenges of development, governance, and sustainability. One of these challenges relates to the management of urban green space, whether municipal parks, forests, or productive land (animal husbandry, vegetable or fruit production). This paper draws on case study research of forestry associations in Galicia. We pay specific attention to the role of comuneiros (commoners): parishioners, who collectively own and manage often‐neglected green spaces: planting or rejuvenating forests of native species to enhance ecological services (water retention, fire prevention, biodiversity) while also including productive functions such as forest fruit production and small‐scale animal husbandry. At the same time these activities create social benefits. With the aim of examining the position and strategies of self‐governing forest organizations, we explore the organizational‐institutional environment of the commons and how this facilitates (and/or obstructs) the objective of providing multiple sustainable and health benefits within the parishes, between them, and to nearby urban residents. We conclude that this particular type of management of urban green space provides products (food and non‐food) and services which are not only of private interest in that they create potential new business opportunities but also of high public value.
Assessing Urban Community Gardens’ Impact on Net Primary Production using NDVI
Authors: Parece Tammy E. , Campbell James B.
Published: October 2017

Community gardens are one form of urban agriculture–growing of food and non‐food products for sale or consumption within urban and peri‐urban areas. Urban community gardens provide many benefits, including provisioning of fresh and nutritious foods, supporting environmental education, nurturing social interaction and community building, and contributing to sustainability. In many cities worldwide, urban agriculture is now integrated within urban planning programs. Although social, community, and nutritional benefits of community gardens are well documented, few quantitative assessments of their environmental benefits exist. None have applied Normalized Difference Vegetation Index (NDVI) as an environmental metric. NDVI is widely used in forestry and agriculture to track changes in vegetation phenology, assess vegetation stress and health, and, in urban areas, to separate vegetation from impervious surfaces. NDVI has a positive relationship with net primary production. We used NDVI product from U.S. satellites–Landsats 5, 7, and 8–to assess urban community garden sites. We conducted a time series analysis over the 2007 to 2015 growing seasons (May–September) for three eastern U.S. cities–Roanoke, VA; Pittsburgh, PA; and Buffalo, NY. Our results show that establishment of community gardens alter seasonal NDVI trajectories, sometimes with initial declines, but then increasing over time. Furthermore, NDVI profiles reveal the vigorous character of urban agriculture.
The Impact of Vineyard Abandonment on Soil Properties and Hydrological Processes
Authors: Comino Jesús Rodrigo , Bogunovic Igor , Mohajerani Hadis , Pereira Paulo , Cerdà Artemi , Ruiz Sinoga José Damián , Ries Johannes B.
Published: October 2017

Core Ideas

A Guelph permeameter was used to quantify water movements.

The active vineyard had higher permeability and saturated conductivity than the abandoned one.

Vineyard soils showed a higher variability among seasons and slope positions.

In the abandoned plot, there was a high correlation with gravel, OM, and clay content.

In the vineyard, human impacts on the soil did not allow any key factor to be obtained.

Soil and water resources are affected by land use changes such as land abandonment in vineyards. Changes in water resources and soil water dynamics can result in sudden alterations in erosion rates and trigger land degradation. In this study, we examined the impact of land abandonment on soil properties and hydrological processes in two paired plots: an active and an abandoned vineyard. Laboratory analyses were performed to assess texture, antecedent soil moisture, stoniness, soil water content, and organic matter (OM). A Guelph permeameter was used to quantify the permeability (Per) and saturated hydraulic conductivity (Kfs) at different slope positions and seasons (before and after harvest). Results showed that soil texture and OM were highly modified, and as consequence soil hydrology, after abandonment. We observed a significantly higher Per (26.8 mm h−1) and Kfs (8.4 mm h−1) in the active vineyard soil than in the abandoned one (Per of 14.2 mm h−1 and a Kfs of 5.4 mm h−1). The soils of the active vineyard showed a greater variability among seasons and slope positions. In the abandoned vineyard, the results showed a high correlation of Per and Kfs with gravel content and OM and a negative correlation with the clay fraction. Natural revegetation improved the soil water retention capacity. In the active vineyard, we could not find any relevant factor to explain the soil hydrological properties, and this may be attributed to the disturbance induced by human activities, such as machinery, trampling, and the use of herbicides.