Rubra Var Research Articles

Authentication and Quality Assessment of Plumeriae Rubrae Flos by UHPLC-QTOF-MS/MS and UHPLC-DAD Combined With Chemometrics.

Plumeriae rubrae flos, the dried flowers of Plumeria rubra cv. acutifolia (PRCA), is one of the most important materials of herbal tea in China. Recently, due to the lack of effective quality evaluation standards, it has been found that Plumeria rubra (PR) and Plumeria rubra var. alba (PRVA) were pretended to be PRCA in herbal material markets. To establish an effective method for comprehensive quality assessment on plumeriae rubrae flos, and distinguishing PRCA from its common adulterants, PR and PRVA. In this study, a method combined application of ultrahigh-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS), UHPLC with a diode array detector (UHPLC-DAD), and chemometrics was developed for qualitative and quantitative analysis of PRCA, PR, and PRVA, based on their multiple components. A total of 26 components were identified by UHPLC-QTOF-MS/MS, including nine flavonoids, eight iridoids, seven phenolic acids, and two coumarins from PRCA. Quantified fingerprints were established and validated using UHPLC-DAD based on 18 chemical markers in PRCA, PR, and PRVA samples. The multivariate statistical analysis of quantitative results demonstrated clear discrimination of PRCA, PR, and PRVA, which indicated that isoquercetin, luteolin-3'-O-β-D-glucoside, 15-demethylplumieride P-E-coumarate, and 4-O-beta-glucopyranosyl-cis-coumaric acid could be considered the most obvious characteristic components for distinguishing PRCA from PR and PRVA. A combination of quantitative fingerprint and chemometrics analysis provided an effective and reliable strategy for the quality control of PRCA. The current study was prospected to apply a comprehensive quality control method for plumeriae rubrae flos.

Adaptation and Some Quality Parameters of Cool Season Turfgrass Species in Samsun Conditions

The aim of this study is to determine adaptation and quality parameters of some cool season turfgrass cultivars and species, In the scope of this study, leaf form, variation of leaf colour according to the seasons, tiller number, thinning ratio, weed ratio and general appearance of the species were determined. The experiment was established according to confounding design with four replications in Samsun Conditions at November, 2010. According to 1000 seed weight and characteristics of the plants seeding ratios were determined as pure and viable seed as follows; Lolium perenne 40 g m-2, Festuca rubra var. rubra and Festuca rubra var. commutata 30 g m-2, Festuca arundinacea 40 g m-2, Poa pratensis 20 g m-2, Festuca rubra trichophylla 30 g m-2, Agrostis stolonifera and Agrostis tenuis 5 g m-2, Festuca ovina 25 g m-2. According to the results obtained from this study it was determined that species/cultivars have some superiority to each other because of their different morphological and physiological characteristics. When we consider weed competition, Lolium perenne and Festuca arundinaceae cultivars have to be added to the mixture in order to decrease weed competition. There was colour variation distinctively depending on the seasons for all species. But, compare to the others, cultivars of Agrostis sp. and Poa pratensis cultivars have the potential to keep leaf colour in different seasons. Leaf form and appearance of Festuca rubra, Poa trivialis and Festuca ovina are better than the others. In order to keep good conditions of turfgrass areas, especially after cutting in summer period, Poa pratensis and Poa trivialis should added in mixtures to get benefit their higher regenerating power.

Taxonomic Revision of Escallonia (Escalloniaceae) in Argentina

A taxonomic revision of the genus Escallonia in Argentina, based on the study of herbarium specimens and field work, is presented. Descriptions, nomenclatural treatment, an identification key, and comments on habitat and distribution are given for each species. Drawings not included in previous works are published here for the first time. Also, a plastid DNA network, combining sequences from previous studies, is included. On the basis of morphology and DNA variability, we recognized 17 species of Escallonia in Argentina. Lectotypes are designated for Escallonia resinosa var. dodoneifolia, E. sellowiana, E. longidens, E. rahmeri, and Stereoxylon virgatum. Second-step lectotypifications are designated for Escallonia bifida, E. vaccinioides, E. vaccinioides var. guaranitica, E. spiraeoides, E. adscendens, E. rosea, E. duplicatoserrata, E. tucumanensis, and Stereoxylon corymbosum. Inadvertent lectotypifications were corrected for Escallonia alpina var. glaberrima, E. bellidifolia, E. vaccinioides, E. vaccinioides var. guaranitica, E. spiraeoides, E. adscendens, E. tucumanensis, and Stereoxylon corymbosum. A new synonym (E. rubra var. dumetorum under E. rubra) is proposed.

In vitro Synergestic activity of Basella alba rubra var. and Beta vulgaris L. against Staphylococcus aureus and Streptococcus pyogenes

<i>In vitro</i> Synergestic activity of <i>Basella alba rubra</i> var. and <i>Beta vulgaris</i> L. against <i>Staphylococcus aureus</i> and <i>Streptococcus pyogenes</i>

PROPAGANTION, ECOLOGICAL-BIOLOGICAL FEATURES, SIGNIFICANCE OF RED FESCUE (FESTUCA RUBRA L., POACEAE)

It is shown that red fescue form (Festuca rubra var. genuina Gr. et Godr.) is the long root-curtin cereal and a perfect «builder» of turf couver. This type contains more mezophytes than another types, though there are forms from gigrophytes to mezokserofit. In Ukraine it’s the common type of meadow herbage which can be find in forest, foreststeppe zone, in Carpathians. In the steppe zone it is mostly adventitious.&#x0D; Original never described before property of Festuca rubra var. genuina Gr. et Godr. is the optional ortotrophnyh ( vertical growth). This phenomenon contributes to the formation of vertical orientation turf (registered in shading conditions and increased air humidity). Support and the basis for this are the Tree trunks and rocks are herewith its support.&#x0D; Festuca rubra is one of the most applicable plants for making of high quality lawns and antierosion sod cover in the steppe zone including the industrial pollution conditions, in the zone of spraying by sea spray as well as for growing of “roll turf”. &#x0D; Ecological-biological properties of Festuca rubra give the big possibilities for improvement of its range, the most closely adapted to the specific conditions of habitat in the steppe zone and introduction of high-performance seed here.

PROPAGANTION, ECOLOGICAL-BIOLOGICAL FEATURES, SIGNIFICANCE OF RED FESCUE (FESTUCA RUBRA L., POACEAE)

It is shown that red fescue form (Festuca rubra var. genuina Gr. et Godr.) is the long root-curtin cereal and a perfect «builder» of turf couver. This type contains more mezophytes than another types, though there are forms from gigrophytes to mezokserofit. In Ukraine it’s the common type of meadow herbage which can be find in forest, foreststeppe zone, in Carpathians. In the steppe zone it is mostly adventitious.&#x0D; Original never described before property of Festuca rubra var. genuina Gr. et Godr. is the optional ortotrophnyh ( vertical growth). This phenomenon contributes to the formation of vertical orientation turf (registered in shading conditions and increased air humidity). Support and the basis for this are the Tree trunks and rocks are herewith its support.&#x0D; Festuca rubra is one of the most applicable plants for making of high quality lawns and antierosion sod cover in the steppe zone including the industrial pollution conditions, in the zone of spraying by sea spray as well as for growing of “roll turf”. &#x0D; Ecological-biological properties of Festuca rubra give the big possibilities for improvement of its range, the most closely adapted to the specific conditions of habitat in the steppe zone and introduction of high-performance seed here.

Water balance of Mediterranean karst soil in Bosnia and Herzegovina as a water conservation and erosion control factor

This research was carried out in the locality of Dubljani in Popovo Polje, which is one of a series of typical Dinaric karstic poljes situated within the Mediterranean part of Bosnia and Herzegovina. Previous research has shown that the Mediterranean part of Bosnia and Herzegovina has the largest surplus and deficit of water at the same time. Because of this, we wanted to explore how much of the water goes to drainage runoff, and then how slope affects the surface runoff. The ultimate goal was to find a way to conserve water and prevent erosion in these natural conditions. Precipitation, drainage runoff, surface runoff and soil erosion were measured at the agro-hydrological station during the experimental period with the goal of understanding the problem of water erosion intensity. In order to study the relationship between precipitation and drainage runoff, six lysimeters with different soil depths were installed (1.3 m, 1.0 m, 0.5 m, 0.3 m and one karst simulation). In addition, six metal cassettes were set up and filled with the same soil used by the lysimeters to simulate inclinations of 1, 5 and 10%, involving both bare and grass-covered soil (Lolium perenne L., Poa pratensis L., Festuca rubra var. fallax Thuill., Dactylis glomerata L., Trifolium repens L., Trifolium pratense L.), and the total water runoff and soil erosion were monitored. The results indicate large differences in the agro-hydrological budget between bare rocky soil and loamy-clayey soils of different depths. The drainage runoff coefficient during the first year ranged from 0.33 in deep soil to 0.50 in shallow soil, while in the second year it ranged from 0.38 to 0.58. The results of the drainage runoff coefficient for the bare karst was higher than 0.70 during both years. The results of the measurement of the total surface runoff and soil erosion indicate that the impact of inclination can be mitigated by grass cover. The surface runoff measurements during the 2 years for both bare and covered soil at the same inclinations show a reduction in the surface runoff from 32 to 86%. The reduction of erosion in covered soil compared to bare soil ranged from 55 to 75%in the first year, while in the second year, erosion in the covered soil was almost completely stopped (a reduction of > 95%). This study shows a huge impact of soil cover on the agrohydrological budget where runoff potential increases with soil depth. Moreover, the results confirm the role of vegetation role in reducing runoff and soil erosion, which is important for better conservation of moisture in the soil. In future research, attention should be paid to the seasonal character of erosional processes.

Anxiolytic effects of Plumeria rubra var. acutifolia (Poiret) L. flower extracts in the elevated plus-maze model of anxiety in mice

Interest in alternative medicine and plant-derived medications that affect the “mind” is growing rapidly since last two decades. The aim of the present study was to investigate the effects of ethanolic extract of flower of Plumeria rubra (PR) along with its fractions in the elevated plus-maze (EPM) model of anxiety. The P. rubra extract or its fractions was administered orally to male Swiss mice, at graded doses, 1h prior to behavioural assessment. The PR extract at the dose of 100mg/kg p.o., significantly increased the time spent in the open arms of the EPM. Further, the anxiolytic properties of hexane, chloroform and butanolic soluble and insoluble fractions at one-fifth of the original dose were also observed in the EPM task. Out of which butanol insoluble fraction showed significant anxiolytic activity comparable to standard anxiolytic drug, diazepam. Further, pretreatment with crude ethanolic extract and butane insoluble fraction showed no significant effects in the horizontal activity, total distance travelled and stereotypy count in the animal activity monitor and had no motor in-coordination side effects in the rotarod test in mice. These observations suggest that the flower extract of P. rubra and its insoluble butanolic fraction might possess significant anxiolytic potential to be pursued further for drug development process.

Rizomlu Kırmızı Yumak (Festuca rubra var. rubra) ile Tesis Edilen Yeşil Alanda Atıksu Arıtma Çamurunun Tesis Gübresi Olarak Değerlendirilmesi

This study was carried out to determine the assessment as establishing fertilizer o f biosolid in a sod establishment with creeping red fescue (Festuca rubra var. rubra) in Van in 2007-2008 years. In this study carried out using randomized complete-block design with three replications, it was evaluated the doses of 3, 6, 9 and 12 t/da biosolid (sewage sludge) and application as establishing fertilizer o f farmyard manure that was used as a control. In the study, criteria such as plant height, green grass yield, plant covered area, weed rate, color and turfgrass quality o f creeping red fescue were evaluated. In the result o f study, in observations at the first period o f primary year, plant height, green grass yield and plant-covered area values were found to be a low in applications where high doses o f biosolid were used and at the further periods, these values were found to be a high. Color and turfgrass quality criteria in fields used as establishing fertilizer of biosolid give generally the best results according to fields used the farmyard manure in each observation period. In the result o f this study, it has been considered that biosolid was increased the turfgrass performance o f creeping red fescue and was an important alternative to a farmyard manure in establishing stage.

Genetic Variability of Thermal Nymphaea (Nymphaeaceae) Populations Based on ISSR Markers: Implications on Relationships, Hybridization, and Conservation

The globally widespread genus Nymphaea exhibits a wide range of morphological and taxonomical diversity. The intrusion of a cultivated variety by progressive propagation and its affect on aquatic habitat is demonstrated in this case study. We have studied the genetic diversity, population, and stand structure of the neophyte Nymphaea × ‘Panama Pacific’ as well as other species found in Lake Hévíz and dikes nearby using inter-simple sequence repeat (ISSR) markers. The ISSR assay revealed a low genetic variability for the small populations of Nymphaea caerulea, Nymphaea lotus var. thermalis, and a medium level for Nymphaea alba, Nymphaea rubra var. longiflora, and Nymphaea × ‘Panama Pacific’. The evolutionary genetic status of individuals found in the overlapping cultivation area of Nymphaea × ‘Panama Pacific’ and N. caerulea was affirmed to be of hybrid origin by reticulate network analysis and with morphological parameters. The Bayesian analysis of hybrid classes and the segregation of the ISSR markers also confirmed the hybrid origin of the individuals in question and revealed that they are falling into F2 or latter genotype frequency classes, indicating the viability and fertility of the hybrids. The set of analyzed species by phylogenetic network analysis of ISSR data has been divided into three major groups according to their evolutionary patterns (subg. Barachyceras, Lotos, and Nymphaea). Our results are in accordance with these three major subgenera within Nymphaea.

Identifying, cloning and structural analysis of differentially expressed genes upon Puccinia infection of Festuca rubra var. rubra

Differentially expressed genes in response to rust infection ( Puccinia sp.) in creeping red fescue ( Festuca rubra var. rubra) were identified and quantified using the mRNA differential display technique. The differentially induced genes were identified as homologs of mitogen-activated protein kinase (MAPK) 3 of Arabidopsis thaliana, stem rust resistance protein Rpg1 of barley and Hsp70 of Spinacia oleracea. The change in the steady state expression levels of these genes in response to rust infection was tested by Northern blot analysis and further quantified by real-time PCR. A steady accumulation of transcripts in the course of rust infection was observed. Full-length transcript of a fescue MPK-3 was obtained by RACE PCR. Its corresponding cDNA encodes a protein with a predicted MW of 42.5 kDa which was mapped onto the structural model of homologs MAPK to illustrate the corresponding MAPK signature motifs. This study, for the first time, presents evidence on the rust infection dependent metabolic pathways in creeping red fescue.

Fescue to the Rescue: Chewings Fescue, Paspalum, and the Application of Non-British Experience to Pastoral Practice in New Zealand, 1880–1920

Abstract Under British settlement, New Zealand’s export income became increasingly dependent upon new and improved pasture for sheep and cattle. While the introduction of familiar pasture plants--such as ryegrass and cocksfoot--was preferred, from the 1880s farmers also experimented with different grass species to suit newly experienced environmental conditions. Both Chewings fescue (Festuca rubra var. commutata) and paspalum (Paspalum dilatatum) were experimented with and adopted for pasture up to the 1920s. While the discovery of ecological limits partly determined the chain of events, the story of these adoptions equally reflects the influence of human and social factors upon the pattern of agricultural change. Individuals and newspapers were more integral to the process of investigating the uses of Chewings fescue and paspalum than departments and government reports. This case study emphasizes Australian and American influences more than British ones, which necessitates the reassessment of all external knowledge in the light of New Zealand’s experience.

Performance and Transition Date of a Turf-type Annual Ryegrass in Comparison to Perennial Ryegrass and Fine Fescues

Perennial ryegrass (Lolium perenne) has traditionally been used to overseed warm-season grasses in the southern U.S. when warm-season sods are dormant due to chilling temperatures. In this study we investigated overseeding turf-type annual ryegrass (two cultivars of L. multiflorum and one cultivar of L. rigidum) and chewing fescue (Festuca rubra var. commutata) as well as perennial ryegrass onto a warm-season common bermudagrass (Cynodon dactylon) sod. The objective was to compare turf quality, turf color, and transition date of turf-type annuals with perennials and other cool-season grasses. Results for turf quality indicated that the annual ryegrass cultivars `Axcella' and `Panterra' (L. multiflorum) compared very well with perennials through March; however, in April and May, perennials were superior for quality. `Hardtop' fine fescue is a hard fescue (F. ovina var. duriuscula). It was inferior to the annuals for turf quality from December to April when the annuals began to die. For turf color, annuals had a lower rating compared to dark green perennials such as `Premier II', `Derby Supreme', or `Allstar'. `Panterra' was darker compared to `Axcella' in March and April. Chewing fescue was intermediate in color compared to annuals and perennials. For turf height, `Axcella' was taller than `Panterra', which were both taller than the perennials, and the fine fescues were shorter than the perennials. For transition in the spring, the annuals had a shorter transition and died about 1 month earlier than the perennials. `Transtar' (L. rigidum) had an earlier transition than the other annuals. The perennials tended to have a longer transition period. The fescues had a very long transition period and were similar to the perennials.

Year-Round Nitrogen Fertilization Effects on Growth and Quality of Sports Turf Mixtures

The effect of three different nitrogen (N) levels applied monthly year-round on the growth and quality aspects of four different sports turf mixtures consisting of perennial ryegrass (Lolium perenne L.), tall fescue (Festuca arundinacea Schreb.), Kentucky bluegrass (Poa pratensis L.), creeping red fescue (Festuca rubra var. rubra L.), Chewings fescue (Festuca rubra var. commutata Gaud.), slender red fescue (Festuca rubra var. trichophlla), and Colonial bentgrass (Agrostis tenuis L.) were evaluated in this three year field irrigated study. Nitrogen was applied monthly at rates of low (2.5 g N m− 2), medium (5.0 g N m− 2), and high (7.5 g N m− 2) starting in the first month after the sowing date in November 1998 and continuing for 34 months. The seasonal average differences in color, quality, cover percentages, and clipping yields of the mixtures were not significant. In contrast, N treatments greatly affected these characteristics, and differences were statistically significant at all the individual sampling dates and for seasonal averages during the three years of this study. Turf color and quality were generally associated with the N fertility treatments. Increasing N significantly (P < 0.01) enhanced the color and quality ratings and increased clipping yields in all turf mixtures. Fall and winter fertilizations significantly (P < 0.01) improved color and quality of turf without winter damage in the experimental area with mild winters. In particular, the high (7.5 g N m− 2) rate resulted in decreased rooting at the both 0–15 cm and 15–30 cm depths.

Taxonomic and nomenclatural notes on Festuca (Poaceae): the Festuca vizzavonae and "F. cyrnea" problem

AbstractMorphological and karyological features show that Festuca vizzavonae and F. rubra var. cyrnea St. Yves &amp; Litard. are taxonomic synonyms and that F. vizzavonae would be the correct name for this taxon at the rank of species. As this name has, however, been generally considered synonymous with F. alpina subsp. briquetii (/F. alfrediana), this would result in a confusing, and therefore disadvantageous, nomenclatural change. A proposal to reject F. vizzavonae is, therefore, being made.

Antitumor principle constituents of Myrica rubra Var. acuminata.

Myrica rubra var. acuminata is a native shrub widely distributed and used as folk medicine in Taiwan for stomach disorders and diarrhea. Column chromatography combined with cytotoxic bioassay-guided fractionation was performed to isolate the antitumor principles from fresh leaves of M. rubravar. acuminata. The 20% MeOH eluate fraction of M. rubra var. acuminata inhibited the viability of HeLa and P-388 cells in an in vitro assay and an in vivo P-388 tumor-bearing CDF(1) mouse model. The percent increase in life span (%ILS) of 20% MeOH eluate fraction was greater than 125%. (-)-Epigallocatechin 3-O-gallate (1) and prodelphinidin A-2,3'-O-gallate (2) were isolated from D-20 as the antitumor principle components. Both compounds can inhibit the growth of HeLa cells, but 1 had lower cytotoxic effects in normal cervical fibroblasts than did 2. Moreover, pretreatment with a caspase-3 specific inhibitor prevented 1- and 2-induced poly(ADP-ribose) polymerase cleavage. In view of these results, we suggest that 1 and 2 can induce apoptosis in HeLa cells and that activation of caspase-3 may provide a mechanistic explanation for their cytotoxic effects. Therefore, we suggest that the 20% MeOH eluate fraction extract is good for health and that M. rubra var. acuminata is an economically valuable plant.

EFFECTS OF NITROGEN APPLICATION TIMING ON GROWTH AND QUALITY OF A TURFGRASS MIXTURE

A 3-year field study was conducted to determine the influence of nitrogen (N) application timing on the growth and quality of a turfgrass mixture consisting of perennial ryegrass (Lolium perenne L.), Kentucky bluegrass (Poa pratensis L.), creeping red fescue (Festuca rubra var. rubra L.), and chewings fescue (Festuca rubra var. commutata Gaud.) under irrigated conditions. Nitrogen was applied annually at the rate of 30 g m−2 year−1, with six application regimes: control (no N), single spring (30 g m−2), single fall (30 g m−2), spring + fall (15 + 15 g m−2), spring + summer + fall (10 + 10 + 10 g m−2), and monthly from April through September (5 g m−2). Color, turf quality, clipping weights, and shoot density were correlated with fertilizer rates and application timing in this study. Fertilization monthly or every 2 months resulted in more uniform color and turf quality and less clipping weights than with comparable heavy spring and fall fertilizations. Heavy N applications in the fall did not cause winter injury and produced significantly darker color and more uniform appearance in early spring than other N applications. All N-fertilization regimes increased shoot density, but spring fertilization stimulated density the most. Nitrogen applied monthly or every 2 months was enough to enhance the color, turf quality, and shoot density of the turf during the growing season but did not greatly affect the growth rate.

Spring‐Applied Nitrogen and Productivity of Cool‐Season Grass Seed Crops

AbstractUnderstanding effects of spring N rates and application timing on seed yield and yield components of cool‐season grass seed crops will help improve N fertilization management. We tested effects of 90, 120, 150, 180, and 210 kg N ha−1, applied at the double‐ridge (DR) stage of development on seed yield and yield components of Chewing's fescue [Festuca rubra L.subsp. fallax (Thuill.) Nyman; syn. F. rubra var. commutata Gaudin], tall fescue (F. arundinacea Schreb.), and orchardgrass (Dactylis glomerata L.) in 1985 and 1986. In a second study, effects of 120 kg N ha−1, applied either at DR, at spikelet initiation (SI), or equally split between the two stages, were tested. Soil type for both experiments was fine‐silty, mixed, mesic Aquultic Argixerolls. Chewing's fescue seed yield was not affected by N rates in 1985 and was the greatest at 90 kg N ha−1 in 1986. Averaged across years, orchardgrass seed yield was the greatest at 120 kg N ha−1. Nitrogen rates did not affect seed yield of tall fescue. Seed yield of all species was most closely correlated with the number of seeds produced per unit area. Seed number per unit area was primarily correlated with the number of seeds produced per panicle in all species; in orchardgrass, the number of panicles per unit area also contributed to total number of seeds produced. Seed yields of all three species were the greatest when N was applied at DR. Split application was not better than application of all N at DR or SI. We concluded that in western Oregon spring application of 90 kg N ha−1 for Chewing's fescue and tall fescue and 120 kg N ha−1 for orchardgrass should be adequate for seed production. For all species, spring N should be applied in one application at DR.

Chemical Dwarfing and the Response of Cool‐Season Grass Seed Crops to Spring‐Applied Nitrogen

AbstractSeed yield response of cool‐season grasses to spring‐applied N is usually limited because of lodging. This study investigated whether chemical dwarfing of these crops improves their seed yield response to spring‐applied N. Chewing's fescue [Festuca rubra L. subsp. fallax (Thuill.) Nyman; syn. F. rubra var. commutata Gaudin], tall fescue (Festuca arundinacea Schreb.), and orchardgrass (Dactylis glomerata L.) were established in September 1983 near Corvallis, OR. Treatments were all combinations of 90, 120, 150, 180, and 210 kg N ha−1 applied at the double‐ridge stage of development, followed by paclobutrazol [(2RS,3RS)‐l‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H1,2,4‐triazol‐1‐yl)‐pentan‐3‐ol] at 0, 0.25, 0.5, and 1 kg a.i. ha−1 applied at floret initiation stage in 1985 and 1986. Averaged across years and N rates, the 1 kg ha−1 rate reduced Chewing's fescue height by 23% and tall fescue and orchardgrass heights by 30%. In the absence of paclobutrazol, Chewing's fescue and tall fescue seed yields were the greatest at 90 kg N ha−1. Paclobutrazol did not affect seed yield response of Chewing's fescue to N rates, but tall fescue seed yield in 1986 was the greatest at 150 kg N ha−1 when only 0.25 kg a.i. paclobutrazol ha−1 was applied. Averaged across N rates, the 0.5 kg ha−1 rate increased Chewing's fescue seed yield by 32% in 1985 and 18% in 1986, and also increased tall fescue seed yield by 32% in 1985 and 23% in 1986. Orchardgrass seed yield was the greatest at 180 kg N ha−1 in both years. Paclobutrazol did not affect orchardgrass seed yield in 1985, and the 1 kg ha−1 rate decreased seed yield in 1986. We concluded that in western Oregon paclobutrazol application at floret initiation does not improve seed yield response of these crops to spring‐applied N, but it would significantly improve Chewing's fescue and tall fescue seed yield, regardless of the N rate applied. Results did not indicate any advantage for applying paclobutrazol on orchardgrass seed crop.

Fine Fescue Species Determination by Laser Flow Cytometry

The close morphological resemblance among tine fescues (Festuca spp.) makes identification and classification of species a difficult problem for turfgrass and taxonomic scientists. Determining ploidy level has become a major taxonomic tool for identifying species of fine fescues. The present study used laser flow cytometry to determine ploidy levels of 48 fine fescue populations (accessions) and thereby infer species classification based on observed and previously reported chromosome numbers. The 10 species of fine fescues examined were strong creeping red fescue (F. rubra L. spp. rubra ), slender creeping red fescue (F. rubra var. littoralis Vasey), Chewings fescue [F. rubra ssp. fallax (Thuill.) Nyman], hard fescue (F. brevipila Tracey), sheep fescue [F. ovina L. ssp. hirtula (Hackel ex Travis) Wilkinson], hair fescue (F. filiformis Pourret), false sheep fescue (F. pseudovina Hackel ex Wiesb), alpine fescue (F. brachyphylla Schultes), bluebunch fescue (F. idahoensis Elmer), and tundra fescue (F. lenensis Drobov). Significant differences were observed between species (P < 0.01) and among populations within species (P < 0.05). DNA content among the 10 species was observed to be highly positively correlated with observed or reported chromosome numbers (r = 0.97, n = 10, P < 0.01). Linear regression analysis (Y =2.1 + 0.23 X) predicted 2C DNA content values for each of the four ploidy levels to be 5.31 pg for diploids (2n = 2x = 14), 8.53 pg for tetraploids (2n = 4x = 28), 11.75 pg for hexaploids (2n = 6x = 42), and 14.98 pg for octoploids (2n = 8x = 56). The observations and results of the present study are consistent with current taxonomic treatments of hard and sheep fescue species as well as the other fine fescue species examined. The information presented should aid breeders in accurately and easily determining primary breeding germplasm with respect to ploidy levels. It may also enable the turfgrass industry to define reliably seed products and the plant collector to begin to assign native and/or naturalized accessions to their proper species categories.