Orchardgrass Cultivars Research Articles

Genetic Variation for Morphology and Maturity Among the Half‐Sib Progeny of Nine Orchardgrass Germplasm Populations

ABSTRACTOrchardgrass (Dactylis glomerata L.) acreage has declined compared to perennial ryegrass (Lolium perenne L.) and tall fescue (Festuca arundinacea Schreb.). With the intent of developing new sources of orchardgrass germplasm, 162 half‐sib families from six orchardgrass germplasm populations and three orchardgrass cultivars were evaluated during 2008 for maturity and plant morphology at locations in Idaho and Utah. Genetic similarity of the populations was also characterized using simple sequence repeat markers. Genetic variation between families differed from zero for seven of the nine traits evaluated, with broad‐sense heritability estimates ranging from 0.26 (flag leaf width) to 0.74 (maturity). For each trait that exhibited genetic variation, half‐sib families were identified that possessed trait values similar to or more extreme than the values corresponding to the included commercial orchardgrass cultivars. Through principle component analysis, potential groupings of half‐sib families with similar phenotypic characteristics were identified; for example, taller plants with earlier maturity. Therefore, germplasm could be targeted for development of improved orchardgrass with maturity and morphology suitable to specific management practices, such as short stature, narrow leaves, and late maturity for mixture with legumes.

English

This study was focused on studying the genetic diversity among pasture grass cultivars using inter-simple sequence repeats (ISSR) markers to determine their genetic background. Six grass cultivars were used in this study: two perennial ryegrass (Lolium perenne L.) cultivars (Aries and Quartet), two endophyte-free tall fescue (Festuca arundinacea Schreb.) cultivars (Fawn and K5666v) and two orchardgrass (Dactylis glomerata L.) cultivars (Tekapo and Niva). Analysis of the 15 selected ISSR primers among the six grass cultivars generated 77 bands, 66 (85.7%) of which were polymorphic. The two perennial ryegrasses cultivars (Aries and Quartet) were distinguished by a 600-bp amplification fragment produced by primer UBC807. The 500-bp amplification fragment was produced by primer UBC825, which was distinguished in Niva, but absent in Tekapo- orchard grass. Furthermore, Fawn-tall fescue was distinguished by a 400-bp amplification fragment produced by primer UBC825. The minimum genetic similarity (GS) value was obtained between the two orchard grass cultivars (Niva and Tekapo), while the maximum GS value was obtained between the two perennial ryegrasses cultivars (Aries and Quartet).   Key words: Genetic variation, inter-simple sequence repeats (ISSR) marker, pasture grass.

Genetic variation and comparison of orchardgrass (Dactylis glomerata L.) cultivars and wild accessions as revealed by SSR markers

Orchardgrass is a highly variable, perennial forage grass that is cultivated throughout temperate and subtropical regions of the world. Despite its economic importance, the genetic relationship and distance among and within cultivars are largely unknown but would be of great interest for breeding programs. We investigated the molecular variation and structure of cultivar populations, compared the level of genetic diversity among cultivars (Baoxing, Anba, Bote, and Kaimo), subspecies (Dactylis glomerata ssp Woronowii) and advanced breeding line (YA02-116) to determine whether there is still sufficient genetic diversity within presently used cultivars for future breeding progress in China. Twenty individuals were analyzed from each of six accessions using SSR markers; 114 easily scored bands were generated from 15 SSR primer pairs, with an average of 7.6 alleles per locus. The polymorphic rate was 100% among the 120 individuals, reflecting a high degree of genetic diversity. Among the six accessions, the highest genetic diversity was observed in Kaimo (H = 0.2518; I = 0.3916; P = 87.3%) and 02-116 had a lower level of genetic diversity (H = 0.1806; I = 0.2788; P = 58.73%) compared with other cultivars tested. An of molecular variance revealed a much larger genetic variation within accessions (65%) than between them (35%). This observation suggests that these cultivars have potential for providing rich genetic resource for further breeding program. Furthermore, the study also indicated that Chinese orchardgrass breeding has involved strong selection for adaptation to forage production, which may result in restricted genetic base of orchardgrass cultivar.

DIVIDEND VL orchardgrass

Bowley, S. R. and Hancock, D. 2011. DIVIDEND VL orchardgrass. Can. J. Plant Sci. 91: 793–795. DIVIDEND VL is a late-maturing orchardgrass (Dactylis glomerata L.) cultivar for silage and hay production in mixtures with alfalfa (Medicago sativa L.) in eastern Canada. The population was developed at the University of Guelph, Guelph, ON. DIVIDEND VL matured at a slower rate when grown in pure stand and in binary mixtures with alfalfa compared with the cultivars OKAY and Rapido. When harvested at the same date, DIVIDEND VL averaged 7% lower in biomass yield compared with OKAY, but the herbage was less advanced in its maturity.

Fatty Acid Profiles of Orchardgrass, Tall Fescue, Perennial Ryegrass, and Alfalfa

ABSTRACTRecent research shows that the meat from beef animals finished on pasture has greater concentrations of omega‐3 fatty acid (FA) and conjugated linoleic acids (CLA) compared with animals finished on high‐concentrate diets. However, little is known about the FA concentrations in forage that might alter these FA in the meat of pasture‐finished beef. The objective was to determine the FA variation between and within forage species commonly grown in pastures in the Midwest. A secondary objective was to identify phenotypic characteristics that may be associated with individual FA. The forages analyzed included multiple cultivars of orchardgrass (Dactylis glomerata L.), tall fescue [Lolium arundinaceum (Schreb.) S.J. Darbyshire = Schedonorus phoenix (Scop.) Holub], perennial ryegrass (Lolium perenne L.), and alfalfa [Medicago sativa L. ssp. sativa and falcata (L.) Arcang.]. Grasses had higher amounts of α‐linolenic (C18:3) acid compared with alfalfa. Conversely, alfalfa had larger amounts of linoleic acid (C18:2) than did the grasses. Correlations between phenotypic traits and specific FA were found; plant total chlorophyll had the greatest correlation to total FA concentration. Overall, there is not a large amount of within‐species variation that breeders could use to make large changes in FA concentrations.

A method to differentiate summer-dormant from summer-active tall fescue and orchardgrass accessions at germination stage

Summer-dormant, cool-season perennial grasses are being used in place of traditional, summer-active cultivars for high-quality winter forage. One reason for this change is the ability of cultivars with summer-dormant attributes to tolerate increasing annual temperature, decreasing precipitation, and repeated severe summer droughts. The mechanism of summer dormancy is still not understood in detail. Cultivar development for summer dormancy typically is conducted under field conditions in environments where summer-active types do not survive summer weather conditions. We developed a method based on germination responses to photoperiod to differentiate summer-dormant from summer-active types of tall fescue [Lolium arundinaceum (Schreb.) S. J. Darbyshire] and orchardgrass (Dactylis glomerata L.). Seed of cultivars with known summer dormancy characteristics was germinated at a constant temperature of 24°C under a range of photoperiods (0–24 h) for 14 days. Total germination, modelled cumulative germination, instantaneous rate of germination, and relative germination (to that in the dark) were analysed. Germination of summer-dormant orchardgrass was similar in the dark and short photoperiods (4–12 h), but it was inhibited by a photoperiod longer than 12 h. Germination of summer-active orchardgrass was promoted by any photoperiod compared with the control (0 h). Short photoperiods (4–12 h) promoted germination of summer-dormant tall fescue, while long photoperiods (>12 h) inhibited germination compared with germination in the dark. Summer-active types of tall fescue did not respond to photoperiod, regardless of length. A validation test using two Mediterranean origin cultivars of orchardgrass with contrasting summer dormancy characteristics and experimental lines of Mediterranean origin tall fescue with known expression of summer dormancy characteristics supported the use of seed germination analysis to differentiate among lines for this trait.

Kayak orchardgrass

Kayak is a high yielding early maturing orchardgrass (Dactylis glomerata L.) cultivar with good level of winterhardiness suited for silage and hay production in western Canada including interior British Columbia. The population was developed at the Agriculture and Agri-Food Canada (AAFC) Research Centre, Lethbridge, AB. In BC and Western Forage Trials (WFTests), Kayak yielded 4% better than the check cultivar Kay under both rain fed and irrigated conditions. Kayak orchardgrass produces 10% more seed yield than Kay while its seed size is slightly smaller than Kay. Key words: Orchardgrass, Dactylis glomerata, high forage yield, winterhardy

Ocena plonowania odnowionego użytku zielonego w dolinie Noteci

The aim of this research was to evaluate the yielding of two medow pasture mixtures with varyiny dominants used in the regeneration of a degenerated grassland. The field research was conducted in years 1998–2001 in the Notec Valey in the village Nowe D bie. The experimental field was established on a degenerated pasture on V quality class soil. In the sowing mixtures the dominant species (30 %) were different cultivars of meadow fescue: ’Skra’, ‘Pasja’, ‘Justa’ (model strain), BAH 197 as well as orchard grass cultivars: ‘Amera’ or ‘Astera’. The remaining components of the mixture were the cultivars of the following species: timothy grass – ‘Kaba’ (10 %), perennial ryegrass – ‘Argona’ (10 %), red fescue – “Atra” (15 %), white clover – ‘Rawo’ (20 %), red clover – ‘Karo’ (15 %). The swards were under cutting and grazing utilization. Cultivars of orchard grass were the ones to develop the best from all the sown dominants. The dynamic development suggests high usefulness of orchard grass cultivars in the sowing of meadows and pastures under similar habitat conditions. The cultivars and breading strain of meadow fescue did not develop well. No major influence of the model cultivars and breeding strain of meadow fescue on the assessed parameters was shown. Among other components of the sowing mixtures perennial ryegrass was the most expansive. The yielding of mixtures was strictly connected with the examined factors. With lower frequency of utilization and better development of the sown dominant a much higher yielding was reported.

Cheam-VR orchardgrass

Cheam-VR is an early-maturing orchardgrass (Dactylis glomerata L.) cultivar with high levels of resistance to Cocksfoot Mottle Virus (CfMV) suited to silage and hay production in regions with moderate temperate climate. The population was developed at the Pacific Agri-Food Research Centre (PARC), Agriculture and Agri-Food Canada (AAFC), Agassiz, BC, in collaboration with AAFC Research Centre, Lethbridge, AB. In BC trials, Cheam-VR yielded 6% better than the check cultivar Potomac without inoculation with CfMV and 15% more than the check when inoculated with the virus. In a southern Alberta trial, Cheam-VR survived for 3 yr and yielded 6% more than a winterhardy check cultivar, Kay. Key words: Orchardgrass, Cocksfoot Mottle Virus resistance, Dactylis glomerata

Haida-VR orchardgrass

Haida-VR is a latematuring orchardgrass (Dactylis glomerata L.) cultivar with high levels of resistance to Cocksfoot Mottle Virus (CfMV) suited to silage and hay production in regions with moderate, temperate climate. The cultivar was developed at the Pacific Agri-Food Research Centre (PARC), Agriculture and Agri-Food Canada (AAFC), Agassiz, British Columbia (BC) in collaboration with AAFC Research Centre, Lethbridge, Alberta. In BC trials, Haida-VR yielded 3% more than the check cultivar Potomac without inoculation with CfMV and 21% better than the check when inoculated with the virus. In a southern Alberta trial, Haida-VR survived for 3 yr and yielded 3% better than a winterhardy check cultivar, Kay. Key words: Orchardgrass, Cocksfoot Mottle Virus resistance, Dactylis glomerata

Effect of Initial Harvest Timing on Cultivar Yield in Cool‐Season Forage Grass Trials

Cool‐season forage grasses have a range of inter‐ and intraspecies heading dates in the spring. Selecting a manageable harvest schedule that does not confound yield estimates through a harvest × maturity interaction is troublesome in forage variety trials. Our objective was to determine the extent of interaction between cool‐season forage grass maturity and initial spring harvest when estimating total season yield. Cultivars of orchardgrass (Dactylis glomerata L.), perennial ryegrass (Lolium perenne L.), smooth bromegrass (Bromus inermis Leyss.), tall fescue (Festuca arundinacea Schreb.), and timothy (Phleum pratense L.) differing in relative maturity were established in silt loam soils in 1997 and 1999 at Rock Springs, PA. Orchardgrass and perennial ryegrass were established at the same site in 2001. After the seeding year, three harvest schedules resulting in four harvests per year were applied: (A) each individual cultivar was harvested when it reached boot stage (R0 stage); (B) all cultivars within a species were harvested when the average cultivar maturity within that species was at boot stage; and (C) all cultivars of all species were harvested when the average maturity of all species/cultivars was at boot stage. Subsequent harvests were taken at 35‐d intervals. There was no cultivar × harvest schedule interaction for dry matter (DM) yields in this research. Tall fescue (12140 kg ha−1 yr−1) was the highest‐yielding and perennial ryegrass (5316 kg ha−1 yr−1) the lowest‐yielding species. Cultivars within each species differed in DM yield. Delaying orchardgrass or smooth bromegrass harvest beyond the boot stage (Harvest Schedule C) resulted in increased yields. The results of this research indicate that timing of initial harvest has no effect on relative cultivar total‐season yield within the species tested.

Potassium Level Suitable for Screening High Magnesium Containing Grass Seedlings Under Solution Culture

There is a continued need for breeding high-Mg grass cultivars with low grass tetany risk. Since interaction between magnesium (Mg) and potassium (K) exists, there is a possibility that genotypes characterized for higher Mg concentration may exhibit contrasting behavior for nutrient uptake with K application. A solution culture experiment was conducted to find a suitable K level for individual selection of high-Mg plants. Three K treatments of 1.0, 5.0, and 25 mM were superimposed. The uptake pattern of Mg, calcium (Ca), and K for approved high-Mg cultivars of Italian ryegrass (Magnet), orchardgrass (Mgwell), and tall fescue (HiMag) were compared with that of control cultivars. The seedlings were evaluated for shoot dry weight, amount of nutrient uptake, and average shoot nutrient concentrations. There was an increase in shoot dry weight grown with higher nutrient solution K levels. The effect of K on the trend of Mg uptake was paralleled among the high-Mg cultivars of the three species. The high-Mg cultivars showed higher Mg uptake and average shoot Mg concentrations than the control cultivars. Potassium uptake and average shoot K concentrations of high-Mg cultivars was always lower than the control cultivars. The greatest difference between the controls and high-Mg plants for average shoot Mg and K concentrations was observed in the plants grown under 5.0 mM level of K. This indicates the effectiveness of screening high-Mg grass seedlings using 5.0 mM level of K under solution culture condition. Methodology introduced in this experiment is aimed at expediting the term necessary for screening high-Mg plants.

Virginia Wildrye Evaluated as a Potential Native Cool‐Season Forage in the Northeast USA

Most forage grasses grown in the northeastern USA are introduced species. Interest in native plant species for conservation and production has increased because of new federal policies. We evaluated northeastern accessions of the native cool‐season grass Virginia wildrye (Elymus virginicus L.) for yield, persistence, and plant morphological traits. Thirteen accessions, one cultivar (Omaha), and one commercial ecotype of Elymus were transplanted into single‐row field plots in late summer of 2000 at Beltsville, MD, Rock Springs, PA, and Big Flats, NY. Two orchardgrass (Dactylis glomerata L.) cultivars were the checks. Yield and morphology (leaf width, length, mass, area, and tillers per plant) data were collected during 2001 and 2002. The Elymus accessions produced as much dry matter (28–57 g per plant) as the cultivar and commercial ecotype. Orchardgrass yielded more than twice as much dry matter than the mean of all Elymus entries (94 vs. 34 g per plant averaged for years and locations). The difference in productivity was related to reduced tillering in Elymus especially during regrowth. Yield per plant was strongly correlated (r = 0.62–0.81, P < 0.01) with the number of tillers per plant. Differences in productivity were also reflected in leaf blade traits, with Elymus having a lower leaf area and mass than orchardgrass. Leaf traits were positively correlated (r = 0.35–0.56, P < 0.05) with plant yield. Some northeastern Elymus accessions would probably perform as well as the commercial sources of Elymus in conservation plantings.

Nutritive Value of Virginia Wildrye, a Cool‐Season Grass Native to the Northeast USA

Interest in native plant species for conservation and production has increased because of new federal policies. We evaluated accessions of the native cool‐season grass Virginia wildrye (Elymus virginicus L.) from the northeastern USA for nutritive value and its association with plant morphological traits. Thirteen accessions, one cultivar (Omaha), and one commercial ecotype of Elymus were transplanted into single‐row field plots in late summer of 2000 at Beltsville, MD, Rock Springs, PA, and Big Flats, NY. Two orchardgrass (Dactylis glomerata L.) cultivars were included. Primary growth was harvested in April (Beltsville) or May (Rock Springs and Big Flats) of 2001 and 2002 and analyzed for neutral detergent fiber (NDF), crude protein (CP), and digestible NDF (dNDF). Nutritive value measures were related to plant morphological attributes [leaf width, length, area, and leaf‐to‐stem mass ratio (LSR)]. Virginia wildrye accessions differed (P < 0.01) in nutritive value and often had lower NDF and higher CP and dNDF than the commercial ecotype, Omaha cultivar, and orchardgrass. The LSR accounted for most of the variation in nutritive value. Orchardgrass was more mature at harvest than Elymus entries and thus lower in nutritive value. Neutral detergent fiber was negatively correlated with LSR (r = −0.26 to −0.74, P < 0.05), whereas CP and dNDF were positively correlated (r = 0.36 to 0.80 for CP and 0.44 to 0.74 for dNDF, P < 0.05). Neutral detergent fiber was also positively correlated (r = 0.27 to 0.86, P < 0.05) with leaf length. Virginia wildrye is comparable to other cool‐season grasses in nutritive value.

오차드그래스 성숙종자로부터 캘러스 유도 및 고효율 식물체 재분화

In an effort to optimize tissue culture conditions for genetic transformation of orchardgrass (Dactylis glomerata L.), an efficient and high-frequency plant regeneration system from seed-derived calli was established. Embryogenic calli induced on MS medium containing 3mg/L 2,4-D and 0.1mg/L BA had significantly improved regeneration ability. Plant regeneration rate was 92％ when embryogenic calli were cultured on N6 medium supplemented with 1mg/L 2,4-D and 3mg/L BA. Among three kinds of medium, MS and N6 medium were optimal for embryogenic callus induction and plant regeneration, respectively. Ho difference in callus induction frequency was observed among four cultivars of orchardgrass, however, "Roughrider" cultivar showed higher regenerability with the frequency of 61％. Addition of maltose to the regeneration medium as a carbon source dramatically increased regeneration frequency up to 69％. A short tissue culture period and high-frequency regeneration system would be beneficial for molecular breeding of orchardgrass through genetic transformation.

Forage Nutritional Characteristics of Orchardgrass and Perennial Ryegrass at Five Irrigation Levels

As water resources become limiting, the need to produce stable amounts of highly nutritional forage increases. An understanding of how levels of irrigation affect crude protein (CP), digestible neutral detergent fiber (dNDF), in vitro true digestibility (IVTD), and neutral detergent fiber (NDF) is critical in pasture forage management. Cultivars of orchardgrass (Dactylis glomerata L.) and perennial ryegrass (Lolium perenne L.) were established under a line‐source irrigation system to evaluate the effect of five water levels (WLs) and three harvest dates on concentrations of CP, dNDF, IVTD, and NDF. Perennial ryegrass forage had higher CP, dNDF, and IVTD and lower NDF concentrations than orchardgrass at all harvest dates and within WLs. The most notable trend in nutritional value across WLs was the near linear increase in CP ranging from 175 g kg−1 at the wettest WL to 217 g kg−1 at the driest WL. Digestible NDF ranged from 709 to 757 g kg−1 at corresponding WLs. These trends were particularly evident later in the growing season. Orchardgrass maturity (early vs. late) had little effect on forage nutritional characteristics across WLs. Combined over WLs, tetraploid perennial ryegrass cultivars averaged higher concentrations of CP, IVTD, and dNDF and lower NDF values compared with diploid cultivars. In general, as water stress increased, forage nutritional value (i.e., CP and dNDF) increased.

Forage Nutritional Characteristics of Orchardgrass and Perennial Ryegrass at Five Irrigation Levels

As water resources become limiting, the need to produce stable amounts of highly nutritional forage increases. An understanding of how levels of irrigation affect crude protein (CP), digestible neutral detergent fiber (dNDF), in vitro true digestibility (IVTD), and neutral detergent fiber (NDF) is critical in pasture forage management. Cultivars of orchardgrass (Dactylis glomerata L.) and perennial ryegrass (Lolium perenne L.) were established under a line-source irrigation system to evaluate the effect of five water levels (WLs) and three harvest dates on concentrations of CP, dNDF, IVTD, and NDF. Perennial ryegrass forage had higher CP, dNDF, and IVTD and lower NDF concentrations than orchardgrass at all harvest dates and within WLs. The most notable trend in nutritional value across WLs was the near linear increase in CP ranging from 175 g kg−1 at the wettest WL to 217 g kg−1 at the driest WL. Digestible NDF ranged from 709 to 757 g kg−1 at corresponding WLs. These trends were particularly evident later in the growing season. Orchardgrass maturity (early vs. late) had little effect on forage nutritional characteristics across WLs. Combined over WLs, tetraploid perennial ryegrass cultivars averaged higher concentrations of CP, IVTD, and dNDF and lower NDF values compared with diploid cultivars. In general, as water stress increased, forage nutritional value (i.e., CP and dNDF) increased.

Plant Density and Environment Effects on Orchardgrass–White Clover Mixtures

ABSTRACTEarlier research indicated that orchardgrass (Dactylis glomerata L.) cultivars affected white clover (Trifolium repens L.) stolon structure during establishment. We conducted a field study to determine if plant density and environment modified the effect of orchardgrass cultivars on white clover. ‘Dawn’ and ‘Pennlate’ orchardgrasses were established at 10‐, 20‐, or 40‐cm spacings in mixture with ‘Will’ white clover in a systematic plant spacing design. Plots were established in September 1996 on a Hagerstown, Berks, or Rayne soil in central Pennsylvania. Orchardgrass was harvested monthly from May to September 1997 and 1998 to determine yield and tiller number per plant. White clover plants were dug from each plant spacing and site in the fall to determine stolon structure. Orchardgrass cultivar did not affect white clover stolon structure. Orchardgrass and white clover plants were larger and more complex on the Hagerstown soil than on the lower fertility Berks and Rayne soils. The highest stolon densities occurred at the 40‐cm plant spacing on the Hagerstown soil in 1998 with >22 m of main stolon m−2 along with 8 m of first‐order branches and 1 m of second‐order branches. On the Rayne soil, plant spacing had little effect on stolon structure. Weed competition was greater on the Rayne soil (788 plants m−2 from 33 species) than on the higher fertility Hagerstown soil (157 plants m−2 from 19 species). Interspecific competition, edaphic factors, and climate interacted to govern the structure of white clover stolons and overwhelmed orchardgrass cultivar effects.

Carbon Isotope Discrimination in Orchardgrass and Ryegrasses at Four Irrigation Levels

Availability of irrigation water is often the limiting factor in the establishment of improved pastures in the U.S. Intermountain Region, and grasses used for pasture should have enhanced water-use efficiency (WUE). Objectives of this study were to describe (i) relationships between carbon isotope discrimination (Δ) and dry matter (DM) yield, and (ii) trends in Δ across four water levels (WL 2, wettest, to WL 5, driest) and two harvest dates under frequent defoliation in cultivars of orchardgrass (Dactylis glomerata L.) perennial ryegrass, (Lolium perenne L.), intermediate ryegrass (L. ×hybridum Hausskn), and festulolium [×festulolium braunii (K. Richt.) A. Camus.]. Within all WLs, orchardgrass cultivars exhibited higher WUE than the ryegrasses, which includes intermediate ryegrass and festulolium. Significantly more variation for Δ within WLs was observed in the ryegrasses than orchardgrass. For orchardgrass, DM yield and Δ were not correlated at WLs 2 to 4. However, they were negatively correlated at WL 5. Correlations between Δ and DM yield were not significant at WLs 2 and 3 for the ryegrasses, but were positive at WLs 4 and 5. To avoid possible declines in DM yield in breeding programs to increase WUE in orchardgrass and the ryegrasses, DM yield should also be monitored.

Grazing and the addition of white clover improves the nutritional quality of orchardgrass cultivars

Two experiments were conducted to determine the nutritional quality of orchardgrass (OG) cultivars under hay and rotational grazing systems during the first 2 production years. Crude protein content was higher and fibre content lower in OG managed as rotationally grazed pasture compared with that harvested as hay. The K:Ca + Mg ratio was reduced and Cu deficiency was ameliorated when OG swards contained white clover. Orchardgrass genotypic × sward management effects were also observed. Key words: Orchardgrass, management, potassium, genotypes, quality, pasture, hay