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Environmental pollution with heavy metals has a negative impact on lawn grasses. Heavy metals are one of the priority pollutants of anthropogenic ecosystems. Earlier, plants Agrostis stolonifera, resistant to cadmium, were obtained using biotechnological method. Plants that are resistant to one heavy metal may be cross-resistant to another. The assessment of the resistance of plants obtained by biotechnological methods to other heavy metals is of practical value. The object of our study was to lawn grass - Agrostis stolonifera L. The aim of this work was to assess the tolerance of the next generation descendants of the regenerant Agrostis stolonifera, resistant to cadmium, to one of the most phytotoxic heavy metals - copper. Cadmium -tolerant plants were more resistant to copper. The tolerance of cadmium – resistant plants to copper is associated with nonspecific mechanisms. However, the increase in plant resistance was not very significant. Therefore, it is more expedient to obtain plants that are resistant to copper. [ABSTRACT FROM AUTHOR]

Cytokinin (CK) is a vital plant hormone that controls many aspects of growth and development in plants. Nitrogen (N) is the indispensable macronutrient needed in plants and also one of the most important limiting factors for plant growth. This study was designed to investigate the simultaneous effects of CK and N on the visual turf quality and antioxidant metabolism of drought-stressed creeping bentgrass (Agrostis stolonifera L.). ‘PennA-4’ creeping bentgrass treated with trans-zeatin riboside at three rates of CK concentrations of 0, 10 and 100 μM (designated by CK0, 10, and 100) and two nitrogen rates with 2.5 and 7.5 kg N·ha-1 every 15 days (designated by low and high N) in a complete factorial arrangement was grown under two soil moisture regimes: well-watered and drought stress. Exogenous CK improved turf quality and delayed leaf wilting under drought stress, especially under high N. The grasses treated with CK10 and CK100 had lower O2- production and H2O2 concentration than those without CK treatment. The CK100 treatment enhanced the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and guaiacol peroxidase (POD) by 25%, 22%, 17% and 24%, respectively, relative to CK0. Moreover, the activity changes of the antioxidant enzyme isoforms were more significant under high N condition relative to low N condition. Our results demonstrated the beneficial impacts of CK and N on physiological reactions, especially antioxidant metabolism, and foliar application of CK at 10 or 100 μM plus 7.5 kg ha-1 N biweekly may improve drought stress resistance of creeping bentgrass. [ABSTRACT FROM AUTHOR]

Main conclusion: First observation that chemical spray can induce limited-transpiration rate under high vapor pressure deficit. It appears that acibenzolar may be key in inducing this water conservation trait. Irrigation and water use have become major issues in management of turfgrasses. Plant health products that have been introduced into the turfgrass market have been observed to improve plant performance in water stress conditions. In this study, we evaluated whether a selection of common plant health products alter the ability of creeping bentgrass ( Agrostis stolonifera L.) to control transpiration under high vapor pressure deficit (VPD). The plant health treatments-Daconil Action, Insignia, and Signature-were applied to plots on golf course putting greens located in Raleigh NC and in Scottsdale, AZ. Using intact cores removed from the putting greens, transpiration rates were measured over a range of VPDs in controlled conditions. In all cases stretching over a 3-year period, bentgrass cores from field plots treated with Daconil-Action limited transpiration under high VPD conditions, while check treatments with water, and others treated with Insignia or Signature did not. Transpiration control became engaged when VPDs reached values ranging from 1.39 to 2.50 kPa, and was not strongly influenced by the field temperature at which the bentgrass was growing. Because all plots in NC had been treated with chlorothalonil-the key ingredient in Daconil Action to control diseases-it was concluded that the likely chemical ingredient in Daconil Action triggering the transpiration control response was acibenzolar. This is the first evidence that the limited-transpiration trait can be induced by a chemical application, and it implies significant potential for ameliorating drought vulnerability in cool-season turfgrasses, and likely other plant species. [ABSTRACT FROM AUTHOR]

Core Ideas: Limited impact of lower clip of the reel is noticed in bentgrass green quality and color.Double cutting and lower clip of the reel does not always lower green speeds.Lower clip of the reel picks up more sands than higher clip of the reel. [ABSTRACT FROM AUTHOR]

Ecological risk assessments for grass species with novel traits are advisable, or required, in order to identify potential environmental harms prior to large-scale cultivation. Credible risk assessments are built upon knowledge of the communities that could be negatively affected by crop-to-wild gene flow, new weeds, or invasive plants. This study focused on two cultivated grasses with different life histories: the exotic, weedy Agrostis stolonifera (creeping bentgrass) and the native Panicum virgatum (switchgrass). Vascular plant communities were analyzed in 190 transects (50 m) in ten habitat types across two ecoregions (inland and coastal) in the northeastern U.S. Ordination plots and dendrogram analysis showed clustering of inland plant community assemblages within habitat types, while coastal plant communities were similar across the habitats studied. Agrostis and Panicum species had unequal distribution across the habitat types and ecoregions. Agrostis species were more common in the inland ecoregion and habitats receiving moderate management or disturbance events. In both ecoregions, A. stolonifera had high co-occurrence values with other exotic Agrostis species, suggesting potential for interspecific gene flow. P. virgatum was most common in inland roadside and wasteland habitats, but was distributed equally in the three coastal habitats. Co-occurrence between P. virgatum and congenerics was infrequent, although one transect had both P. virgatum and the state-listed coastal species Panicum amarum. This is the first study to characterize Agrostis and Panicum plant communities and distribution providing the basis for ecological risk assessments, coexistence-strategies, and geographic exclusion zones. [ABSTRACT FROM AUTHOR]

The article discusses Irish Protestant minister and amateur botanist William Richardson, focusing on his work with a grass called fiorin, also known as fiorthann or Agrostis stolonifera. It examines Richardson within the scientific and intellectual context of the early nineteenth century, commenting on the Enlightenment. The author particularly reflects on intellectual societies and the intellectual world of Belfast, Northern Ireland. Belfast Literary Society founder William Bruce is also considered.

Effects of long-term applications (50, 100 and 200 m3 ha−1y−1) of pig and cow slurries on yield, botanical composition and nutrient content of herbage of an original perennial ryegrass sward were assessed in a three-cut silage system and compared with unamended and fertilized controls in the 36th year of the experiment. Cow slurry at 50 m3 ha−1 produced similar annual herbage DM yield to 200 kg ha−1 fertilizer N in 2006, whereas about 100 m3 ha−1 pig slurry were required to produce a similar amount of DM. The highest slurry application rate significantly influenced sward botanical composition without depressing DM yield. The principal invading species were creeping bent and meadow grasses (similar to findings at a previous assessment in 1981) except in the unamended control (which were common bent and Yorkshire fog). Perennial ryegrass remained a main species in plots receiving fertilizer (31 % annual DM yield) and low slurry rates (38 %) but declined to 3 % annual DM yield at the highest slurry rate where the ability of ryegrass to utilize slurry N and P may have been affected by chemically or physically induced deficiencies of other nutrients (e.g. Ca) or direct physical effects such as smothering. [ABSTRACT FROM AUTHOR]

Knowledge of water use requirements of various grass species is important for identifying grasses that persist with reduced water inputs and also for developing efficient irrigation management practices. This study was designed to examine minimum water requirements for maintaining acceptable quality fairways established to creeping (Agrostis stolonifera L.), colonial (A. capillaris L.) and velvet (A. canina L.) bentgrasses. Field experiments were conducted from July to November in 2002 and 2003. Plots were irrigated at four levels of irrigation on the basis of the percentage of actual evapotranspiration determined with minilysimeters (ETa): 100, 80, 60, and 40% ETa replacement. Turf performance was evaluated by measuring visual turf quality (TQ), canopy spectral parameters, canopy photosynthetic rates (Pn), and soil moisture status. Results generally demonstrated that irrigating at 100% ETa was not necessary to maintain acceptable TQ and physiological processes and that the minimum water requirements depended on species and time of year. Colonial bentgrass required irrigating at 80 to 100% ETa, while creeping and velvet bentgrasses required 60 to 80% ETa to maintain acceptable turf performance in the summer of 2002. During the summer treatment period in 2003, however, irrigating at 60% ETa was sufficient for all three species. Irrigating at 40% ETa in the fall treatment period in both 2002 and 2003 was sufficient to maintain acceptable TQ, canopy Pn, and comparable canopy growth parameters to plots receiving 100% ETa. The results from this study demonstrate the potential for significant water and monetary savings by utilizing deficit irrigation practices on bentgrass species used for golf course fairways. [ABSTRACT FROM AUTHOR]

• Background and Aims To improve the management of grass communities, early plant development was compared in three species with contrasting growth forms, a caespitose (Lolium perenne), a rhizomatous (Poa pratensis) and a caespitose–stoloniferous species (Agrostis stolonifera).• Methods Isolated seedlings were grown in a glasshouse without trophic constraints for 37 d (761 °Cd). The appearance of leaves and their location on tillers were recorded. Leaf appearance rate (LAR) on the tillers and site-filling were calculated. Tillering was modelled based on the assumption that tiller number increases with the number of leaves produced on the seedling main stem. Above- and below-ground parts were harvested to compare biomass.• Key Results Lolium perenne and A. stolonifera expressed similar bunch-type developments. However, root biomass was approx. 30 % lower in A. stolonifera than in L. perenne. Poa pratensis was rhizomatous. Nevertheless, the ratio of above-ground : below-ground biomass of P. pratensis was similar to that of L. perenne. LAR was approximately equal to 0·30 leaf d−1 in L. perenne, and on the main stem and first primary tillers of A. stolonifera. LAR on the other tillers of A. stolonifera was 30 % higher than on L. perenne. For P. pratensis, LAR was 30 % lower than on L. perenne, but the interval between the appearance of two successive shoots from rhizomes was 30 % higher than the interval between two successive leaf stages on the main stem. Above-ground parts of P. pratensis first grew slower than in the other species to the benefit of the rhizomes, whose development enhanced tiller production.• Conclusions Lolium perenne had the fastest tiller production at the earliest stages of seedling development. Agrostis stolonifera and P. pratensis compensated almost completely for the delay due to higher LAR on tillers or ramets compared with L. perenne. This study provides a basis for modelling plant development. [ABSTRACT FROM AUTHOR]

High soil temperature is a critical factor limiting growth of cool-season grasses. This study was designed to examine changes in water, nutritional, and hormonal status in response to high soil temperature for creeping bentgrass (Agrostis stoloniferavar. palustris) and to compare the sensitivity of those parameters to high soil temperatures. Plants of ‘Penncross’ were exposed to 35 °C soil temperature (heat stress) or 20 °C (control) in water baths while air temperature was maintained at 20 °C in growth chambers. Turfgrass quality, shoot growth rate, and root biomass decreased below the control levels at 15, 15, and 10 days of heat stress, respectively, while root mortality increased above the control level at 5 days of heat stress. Relative water content (RWC) of leaves decreased below the control level at 15 days of heat treatment. Root N content increased while P and K content did not change over time at 35 °C. Shoot N, P, and K content decreased below the control level at 15, 15, and 10 days of heat stress, respectively. Root abscisic acid (ABA) content decreased below the control level at 10 days while shoot ABA content increased above the control level at 5 days. The content of cytokinins (zeatin (Z) and zeatin riboside (ZR), dihydrogen zeatin riboside (DHZR), and isopentenyl adenosine (iPA)) decreased below their respective control levels as early as 5 days of heat stress for roots and 10 days for shoots. The decline in cytokinin content was also more dramatic than changes in other parameters. Our results suggested that cytokinin was most sensitive to high soil temperature among parameters examined, suggesting that changes in cytokinins could serve as an early stress indicator for plant responses to high soil temperature; however, decreased water, nutrient (N, P, and K), and cytokinin content, and increased ABA could all contribute to the decline in shoot and root growth for creeping bentgrass exposed to high soil temperatures. [Copyright &y& Elsevier]

Spatial models predict that long-distance dispersal of offspring provides competitive superiority in open environments. We tested this prediction by artificially aggregating ramets of the spreading clonal species Agrostis stolonifera in an undisturbed environment and in an environment where flooding increased open space. We compared the competitive response of this manipulated Agrostis with both the natural ramet distribution of Agrostis and with the naturally aggregated clonal species Alopecurus pratensis. Our phenotypic manipulation of ramet dispersal significantly increased aggregation of clonal offspring, without altering the number of offspring, and thus provided an adequate test of spatial effects. Regardless of flooding, both Alopecurus and the aggregated Agrostis were more suppressed in species mixtures than the natural dispersed form of Agrostis. This demonstrates that long distance dispersal of ramets enhances competitive ability, at least in early stages of succession. [ABSTRACT FROM AUTHOR]

Annual bluegrass (Poa annua L.) and creeping bentgrass (Agrostis palustris Huds. syn. A. stolonifera L.) coexist on golf greens as a dynamic ecosystem in the temperate regions of the United States. In a two year field study, the competitive ability of different populations of annual bluegrass was investigated both in and out of their native environment. In April 2000, at both The Country Club in Cleveland, Ohio, a temperate environment, and Camargo Club in Cincinnati, Ohio, a transition zone environment, 72 plugs of annual bluegrass were removed from golf greens and inserted into polyvinyl chloride pipe measuring 10.2 cm in diameter and 15 cm in length to eliminate root competition between species. Thirty-six plugs then were reestablished into one of three greens at the same golf course, and the remaining 36 plugs were transported to the opposite location and also established into one of three preselected greens. Each plug was centered in a 20.3-cm-diameter sward of 'L-93' creeping bentgrass to provide an initial point of reference. Competitive ability was measured as the rate of increase or decrease in average diameter of each plug. Measurements initially were taken on a bimonthly basis and then on a monthly basis for the remainder of the study. Significant (P <0.05) differences in the location x population interaction were seen in the first 2 months of the study and then not seen again until the last 2 months. The most frequent occurrence of significant (P <0.05) differences was in the variability between greens within a particular location. At each location the native population of annual bluegrass outperformed the imported population. Differences at the beginning of the study are attributed to an additional acclimation period required by the exported population following transportation to the opposite location. From our study, annual bluegrass performance was similar across populations, suggesting that management recommendations can be made on a... [ABSTRACT FROM AUTHOR]

Creeping bentgrass (Agrostis palustris Huds.) is used on putting greens for its fine-leaf texture, consistent speed, smooth ball roll, and year-round color. In recent years bentgrass use has extended into the warmer climates of the southern United States. Being a C3 plant, bentgrass is not well adapted to extended hot and humid environmental conditions. Subsurface air movement systems are now commercially available that can transport air through the root zone to alter soil conditions and potentially improve bentgrass survival. This research investigated the effects of subsurface air movement on the composition of soil gases, matric potential, temperature, and growth response of a sand-based creeping bentgrass golf green. Treatments included: air movement direction (evacuate, inject, and no air) and duration of air movement (0400-0600 Ha, 1000-1800 ha, and 24 hours). Treatment combinations were imposed for 13 days. Subsurface air movement reduced CO2 at the 9-cm depth to values <0.0033 mol.mol-1 when evacuating or injecting air, depending upon duration. Soil matric potentials at a 9-cm depth were decreased by a maximum of 96% when evacuating air for 24-hour duration compared to no-air plots. Soil temperatures at 9 cm were decreased ≈1 to 1.5 °C when injecting air from 1000 to 1800 HR. and 24-hour treatments and increased ≈0.75 °C when evacuating air from 1000 to 1800 HR. Subsurface air movement did not improve creeping bentgrass turf quality or rooting. Although not effective in improving the growth response of creeping bentgrass, subsurface air movement may be a useful tool to improve soil gas composition, reduce excess soil moisture, and potentially reduce soil temperature(s) of heat-stressed creeping bentgrass golf greens. [ABSTRACT FROM AUTHOR]

Creeping bentgrass (Agrostis palustris Huds) is an important turfgrass used on golf course greens and fairways. It is susceptible to a number of fungal pathogens and requires considerable fungicide use for disease control. Transgenic approaches may be useful in improving the level of disease resistance. We have generated transgenic creeping bentgrass plants expressing PR5K from Arabidopsis thaliana (L.) Henyh. PR5K is a receptor protein kinase whose extracellular domain is homologous to the PR5 family of pathogenesis-related proteins. In a field test of plants inoculated with the fungal pathogen dollar spot (Sclerotinia homoeocarpa F.T. Bennett) four of the eight transgenic lines showed delays in disease expression of 29 to 45 days, relative to the control plants. [ABSTRACT FROM AUTHOR]

Creeping bentgrass (Agrostis stolonifera L.) is a commercially important turfgrass used principally on golf courses. Weed control is one of the major problems encountered in golf course maintenance, largely because the major weed, Poa annua L., is another grass species with herbicide responses similar to creeping bentgrass. Development of creeping bentgrass cultivars expressing one of the herbicide resistance genes would provide an effective solution. The prospects of commercialization of transgenic cultivars of creeping bentgrass have raised questions about the potential for pollen-mediated gene flow to related Agrostis spp. In a field study we have measured the frequency of interspecific hybridization between transgenic creeping bentgrass and four related species, A. canina L., A. castellana Boisso and Reut., A. gigantea Roth, and A. capillaris L. Interspecific trausgenic hybrids were recovered between creeping bentgrass and A. capillaris and A. castellana at frequencies of 0.044 and 0.0015%, respectively, which were considerably lower than intraspecific transgenic progeny recovery in the same experimental plots (0.631%). No interspecific transgenic hybrids were recovered with A. gigantea or A. canina. [ABSTRACT FROM AUTHOR]

Explores the growth and physiological responses of creeping bentgrass (Agrostis palustris huds. cv. Penncross) to changes in air and soil temperatures. Influences of air versus oil temperature on turf quality, physiological activities and root growth; Improvement of turf quality via reduction of soil temperature under high ambient temperature conditions.

Life-history variation among four ecologically contrasting populations of Agrostis stolonifera was examined using a reciprocal-transplant technique in natural habitats. Survival, growth and flowering were mainly determined environmentally across Transplant sites, although population effects in growth and flowering were present. Significant population-transplant-site interactions were also detected. Survival tended to be lower in summer than in winter, and alien populations tended to be more negatively influenced by the change of seasons than home populations. Phenotypic correlations between life-history determinants (survival, growth and flowering) tended to be positive, mainly due to their common environmental component. It is argued that the analyses of life histories, in particular for clonal organisms, Should focus on the dynamics of separate ramets of known genotype. [ABSTRACT FROM AUTHOR]

Colonization and differentiation were studied in four populations (inland meadow, salt-marsh, polder and sand-dune) of the widespread grass Agrostis stolonifera. A common-garden experiment showed that the overall population variability could be divided, through the use of principal component analysis, into three groups of characteristics: a group determined by the number and size of stolons, a group determined by reproductive characteristics and a group determined by the yield of above-ground vegetative biomass. A relationship was found between plant architecture and habitat: a few, long and thick stolons in the productive meadow site: numerous, short and thin stolons in the salt-marsh site; a few, long and thin stolons in the bare and nutrient-poor sand-dune site; and the joint occurrence of all three biotypes in the polder site. Significant difference in means between colonizing and non-colonizing populations were found for the number of inflorescences and reproductive biomass. Within-population variation differed significantly between populations. The meadow populations was least variable, probably caused by the almost complete absence of sexuality in this population. Stolon length, stolon diameter and leaf width were the characteristics with the lowest coefficients of variation within each populations, suggesting the importance of these characteristics in population maintenance. Differences in clonal structure, as detected by isozyme analysis, were most pronounced between the meadow population on the one hand (a few large clones) and the salt-marsh, polder and sand-dune populations on the other (higher density of small clones). [ABSTRACT FROM AUTHOR]

Curvularia lunata is reported as a minor pathogen of adventitious roots of Agrostis palustris. C. lunata isolates from roots of A. palustris were evaluated for their ability to infect adventitious roots at temperatures ranging from 23 to 48°C. All isolates of C. lunata decreased both the shoot and root growth of root-inoculated plants during a 10-week observation period, but failed to produce the foliar symptoms observed in the field. Shoot and root weights of inoculated plants were 47-66% and 55--69° of their respective controls. Infected roots were light tan in colour without lesions or rot, and infections were restricted to root hairs and cortical tissue. These observations are discussed relative to the nature of the pathogenicity of C. lunata as a root pathogen and its potential function in a root disease complex. [ABSTRACT FROM AUTHOR]

Scanning electron microscope examination of the morphology of adaxial and abaxial leaf surfaces of salt spray-tolerant and normal plants of Agrostis stolonifera L., Dactylis glomerata L. and Holcus lanatus L. was carried out. Differences were found in degree and types of waxiness of epidermal cells, number and size of macro-hairs and prickles, epidermal cell lengths and extent to which stomata were sunken. These differences were consistent with a reduction of the wettability, and hence salt spray damage, to adaxial leaf surfaces. Abaxial leaf surface differences were much less pronounced. [ABSTRACT FROM AUTHOR]

Tolerance to sodium chloride in solution culture and its genetic basis has been assessed for populations of Festuca rubra L., Holcus lanatus L., Agrostis stolonifera L., and Dactylis glomerata L. from salt marsh, spray zone, and inland habitats. Two populations of F. rubra from salt marshes and one population of A. stolonifera from a spray zone showed significant NaC1 tolerance. However, in the main, responses of populations to increasing NaCl in the rooting medium showed little relationship with electrical conductivity or Na content of the soil. Narrow-sense heritability estimates were high for all populations, except for one F. rubra population from a salt marsh and the population of A. stolonifera from a spray zone. Broad-sense heritabilities were high for all populations suggesting high genetic components for variation in NaCl tolerance. [ABSTRACT FROM AUTHOR]

Vegetation changes on the steeply-sloping batters and near-horizontal berms, excavated 0.3 m above dry-weather water level to form the flood relief stage of a two-stage channel along the River Roding near Abridge, Essex, were monitored during 1980-82. The mean number of species per 0-25 m² was greatest during the first summer after berm excavation. Diversity (H′) was consistently greater on batters compared with berms, and in ungrazed compared with grazed sites. Grass species dominated the vegetation in all areas. With the exception of Agrostis stolonifera L. and Alopeeurus geniculatus L., invasion by native species was inhibited by cattle grazing. Most of the agriculturally-productive grasses in the seed-mix performed poorly in ungrazed areas. By the third year there were significant ftoristic differences between ungrazed batters and berms. Arrhenatherurn elatius (L.) Beauv. ex J. & C. Presl and Dactylis glomerata L. were more abundant on the freely drained batters (P < 0.01), while Agrostis stolon:fern and Rum.ex spp. were more abundant on the berms (P < 0.001). phalaris arundinacea L. was confined to berms, growing prolifically in poorly-drained areas. In ungrazed areas, tall (>0.76 m) plants, especially reeds, represented a flood hazard by the third summer because more than 25% of the flood channel was filled with vegetation. In contrast, reeds did not grow on ungrazed berms excavated 0.8–0.9 m above dry-weather water level. Creeping grasses are recommended for seeding ungrazed high level berms excavated to one side of an otherwise undisturbed river channel. Two-stage channel construction has considerable potential as an ecologically acceptable method of flood alleviation along small clay rivers, but the amount of land required for berm excavation may limit the scope for this type of river management. [ABSTRACT FROM AUTHOR]

The article presents a study on the influence of iron and manganese and waterlogging on the growth and distribution of Agrostis stolonifera, Festuca rubra, Carex flacca and Carex nigra. Results showed that in terms of the plants' appearance, there were no visible differences between A. stolonifera and C. flacca in various treatments applied. However, small dark brown spots were observed on some leaves of F. rubra in the manganese treatment. The shoot manganese content of all species, except C. nigra, increased with increasing manganese content of the culture solutions. Also, growth of the Carices was enhanced by increasing the concentration of manganese.

The article presents a study on the influence of the relationship among iron and manganese and waterlogging on the growth and distribution of Agrostis stolonifera, Festuca rubra, Carex flacca and Carex nigra. It states since C. flacca is the only one of the four plants to occur in dune, slack and intermediate habitats were also collected and examined to identify whether the experimental tretments were actually simulating the natural environment in this respect. Results showed that the plants in dune sand behaved differently than those in slack sand. In all cases, the increasing wetness from the dune to the slack sites was associated with a marked increase in the iron and manganese content of shoot and root tissues.

The article presents a study on the effects of phosphorus content in soil on the growth of the plant Agrostis setacea. It mentions that studies on the differences of adaptive behaviors in plants to the shortage of nutrients in soil are hard to quantify. The study argues that in the study of Agrostis, the supply of phosphorus in soil must be low to compare growth and survival rates. An experiment was carried out using soil samples from Haldon Ridge, Devon which were examined for nutrient content. Plants were grown on culture solutions. An overview of the study is provided.

The article compares the calcium uptake and the growth responses of Agrostis canina, Agrostis setacea, Agrostis stolonifera and Agrostis tenuis to various calcium concentrations. Information on the soil and water cultures used in the experiments is presented. A detailed description of the preparation of material for analysis is presented. The soils used in the study were collected from plots on the Haldon Ridge, Devon, on which field trials had been carried out earlier. The sources of seeds used in the study are presented.

The article presents a study on six grass species, including Lolium perenne, Cynosurus cristatus, Agrostis stolonifera, A. tenuis, A. canina and Nardus stricta, and their respective responses to varying calcium levels in sand culture. It states that the six species were harvested after the treatments at three separate times. Results showed that Lolium perenne, Agrostis stolonifera and Cynosorus cristatus increased their growth with an increase in calcium at lower levels, while A. tenuis and A. canina increased their growth at all levels. Nardus stricta, however, increased its growth in calcium, but was depressed at higher levels.

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The article compares plant growth and distribution in relation to waterlogging, which means simulated slack moisture regime, with focus on the growth of dune and dune slack plants in Glamorganshire, Wales. The article also investigates the effect of different water regimes on the growth of Agrostis stolonifera, Festuca rubra, Carex flacca and Carex nigra in pots of sand in a glasshouse. The study found that waterlogging caused a considerable reduction of soil compared with the freely draining control treatment and also caused reduction of tiller production by the grasses.

We needed a reliable way to identify species and confirm potential interspecific and intergeneric hybrids in a landscape level study of gene flow from transgenic glyphosate-resistant Agrostis stolonifera (Poaceae) to compatible relatives. We developed 12 new polymorphic chloroplast microsatellite markers to aid in identifying species recipient of transgenic pollen both within the Agrostis complex and the related genera Polypogon. [ABSTRACT FROM AUTHOR]

Black layer has been associated with a severe decline In the quality of turf on putting greens. It was suggested that the black layer results from dissimilatory sulfate (SO42-) reduction. This study was done to determine if SO42- reduction occurs in an existing black layer. Radioactive 35SO42- was used to calculate the rate of SO42- reduction in intact soil cores taken from an existing black layer in a 'Penncross' creeping bentgrass (Agrostis palustris Huds. 'Penncross') putting green. When 10-3 M 35SO42- with a specific activity of 1.554 x 105 Bq⋅mg-1 SO4 2- was injected into a core it reduced to sulfide (35S2-) at a mean rate of 7.1 nmol sulfur (S)/cm³ soil/d. Injecting azide (N3-) or molybdate (MoO42-) at 10% w/v with the label reduced the rate of SO42- reduction to 0.03 and 0.01 nmol S/cm³ soil/d, respectively. The effect of N3- confirmed that reduction of SO42- was biological, while the effect of MoO42- confirmed that the entities responsible for the reductive cycling were sulfate-reducing bacteria (SRBs). This was the first proof that biological reduction of SO42- produces S2- in a black layer from a creeping bentgrass putting green. It was concluded that the respiration of indigenous SRBs was linked to development of this black layer. Thus, a key to successfully controlling black layer in putting greens must Involve regulating the respiratory activities of SRBs. [ABSTRACT FROM AUTHOR]

The article focuses on a study on the development, characteristics and uses of Alpha and T-1 creeping bentgrass. It states that the objective in breeding the said cultivars was to compete more effectively with annual bluegrass under golf conditions. The two sources of the origins of Alpha and T-1 are presented. Common characteristics of the cultivars are discussed. The results of the study are also presented.

Reports that the genetically modified (GM) creeping bentgrass used for golf courses in North America can cross-pollinate wild grasses, according to a study conducted by a team in the U.S. Environmental Protection Agency in 2004. Reasons behind the use of GM grass; Actions taken by the government to counter gene flow; Comments from David Gardner, a bentgrass expert at Ohio State University's department of horticulture and crop science in Columbus, regarding the production of pollen by the grass on a golf course.