13 MOTILITY CHARACTERISTICS OF SPERMATOZOA FROM BULLS GRAZING TALL FESCUE PASTURES

2014 ◽  
Vol 26 (1) ◽  
pp. 121
Author(s):  
J. P. Harris ◽  
J. L. Edwards ◽  
L. A. Rispoli ◽  
N. R. Rorhbach ◽  
T. M. Prado ◽  
...  
Keyword(s):  
Liquid Nitrogen ◽  
Tall Fescue ◽  
Ergot Alkaloid ◽  
Festuca Arundinacea ◽  
Fixed Effects ◽  
Block Design ◽  
Computer Assisted ◽  
Sperm Analysis ◽  
Scrotal Circumference ◽  
Cold Room

Fertilisation is less than expected with spermatozoa from bulls consuming toxic endophyte-infected (E+) tall fescue. The objective of this study was to evaluate motility characteristics of spermatozoa from bulls grazing tall fescue pastures using computer-assisted sperm analysis (CASA). Semen was collected from six Angus bulls (average age = 15.1 ± 0.04 months) during a three-month grazing study. Bulls grazed Kentucky 31 tall fescue (Festuca arundinacea Schreb.) infected with Neotyphodium coenophialum, an ergot alkaloid-producing endophyte (n = 3), or Jesup tall fescue with Max-Q™ (NTE), a non-ergot alkaloid producing endophyte (n = 3), and grouped by body weight and scrotal circumference to graze pastures from April 18 to June 26. Semen was collected once per week between 0600–0800 h beginning in mid-May and ending the last week of June. Gross motility and morphology was evaluated before extending with Bioxcell® animal protein-free formula (IMV, Aigle, France) and antibiotics (CSS 100, 2% of total volume). Extended semen was then evaluated using CASA to determine final dilution and packaged into straws (20 million sperm/straw), where equilibration occurred over 3 h in a cold room at 4°C. Straws were frozen for 7 min in static vapor of liquid nitrogen and plunged into goblets filled with liquid nitrogen. Semen was thawed and assessed using CASA at 0 and 3 h post-thaw. Data were analysed as a randomised block design with the fixed effects of treatment, blocking on semen collection date, utilising the mixed models procedure of SAS 9.2 (SAS Institute Inc., Cary, NC, USA). Data were tested for normality (Shapiro-Wilk W ≥ 0.90), and treatment differences were determined using F-protected least significant differences. Path velocity (P = 0.001) and progressive velocity (P = 0.003) were lower in spermatozoa from bulls grazing E+ during the last 2 weeks of collection in June independent of time of assessment post-thaw. Sperm head area decreased in size in spermatozoa from E+ grazing bulls at 3 h post-thaw (P = 0.04) compared with NTE grazing bulls. Percent of rapid (progressive % with path velocity >50 μm s–1) and medium (progressive % with path velocity <50 μm s–1 but > 30μm s–1) velocity spermatozoa was decreased for E+ grazing bulls compared to NTE grazing bulls (P < 0.0001 and P = 0.004, respectively) and was accompanied by an increase in static (immobile) spermatozoa from E+ bulls (P < 0.0001). These findings indicate that spermatozoa movement and velocity are impaired in bulls grazing E+ tall fescue pastures compared to bulls grazing NTE tall fescue pastures after the freeze and thaw process, which may explain decreased fertilisation and cleavage rates of oocytes co-incubated with these spermatozoa.

Determining the Rate of Ergot-alkaloid Degradation in Toxic Endophyte-infected Tall Fescue Hay and Haylage During Long Term Storage

2021 ◽  
Vol 99 (Supplement_2) ◽  
pp. 22-22
Author(s):  
Charles A Zumbaugh ◽  
Susannah A Gonia ◽  
Kathryn M Payne ◽  
Thomas B Wilson
Keyword(s):  
Tall Fescue ◽  
Ergot Alkaloid ◽  
Fixed Effects ◽  
High Performance ◽  
Nutritive Value ◽  
Day Treatment ◽  
Random Effect ◽  
Storage Period ◽  
Neutral Detergent Fiber ◽  
Experimental Unit

Abstract The objectives of this experiment were to determine changes in the nutritive value and ergot alkaloid concentrations of endophyte-infected tall fescue hay and haylage during a 180-d storage period. Forage from a single field of Kentucky-31 tall fescue was cut for hay in late June and allowed to dry in the field. The dry matter (DM) of the windrow of cut forage was measured every 2 h after clipping. Forage was sampled from the windrow in 6 location blocks once forage DM reached target levels for haylage and hay treatments. Haylage and hay samples were taken when the DM of the windrow reached 50% and 80%, respectively. Seven subsamples of each treatment within block were chopped to 1.91 cm in length with a lettuce chopper and vacuum sealed in oxygen-excluding bags. Sample bags were stored indoors and opened at 30 d intervals over the 180-d storage period. Samples were analyzed for pH, nutritive value, and individual ergot alkaloid concentrations using high-performance liquid chromatography. Within each storage day, treatment within block was considered the experimental unit. Data were analyzed in SAS using the MIXED procedure with fixed effects of treatment, day, and the treatment by day interaction. Location block was considered a random effect. As expected, pH was decreased for haylage compared to hay at all time points (P &lt; 0.01) and DM was greater (P &lt; 0.01) for hay compared to haylage. Neutral detergent fiber values were greater (P &lt; 0.01) for hay compared to haylage and declined during storage (P &lt; 0.01). Total ergot alkaloid concentrations did not differ by treatment (P = 0.61), but ergovaline concentrations declined (P &lt; 0.01) during storage. Collectively, these results indicate minimal differences in nutritive value and ergot alkaloid concentrations between hay and haylage during storage, and that ergovaline concentrations decline during storage.

51 CHANGING ROOSTER SPERM MEMBRANES TO FACILITATE CRYOPRESERVATION

2012 ◽  
Vol 24 (1) ◽  
pp. 137 ◽  
Author(s):  
K. M. Tarvis ◽  
P. H. Purdy ◽  
J. K. Graham
Keyword(s):  
Liquid Nitrogen ◽  
Sperm Motility ◽  
Membrane Damage ◽  
Membrane Integrity ◽  
Computer Assisted ◽  
Membrane Composition ◽  
Sperm Analysis ◽  
Unsaturated Lipids ◽  
Multiple Comparison Test ◽  
Nitrogen Vapor

Cryopreservation damages rooster sperm membranes. Part of this damage is due to membrane transitioning from the fluid to the gel state as temperature is reduced. Some of this damage may be prevented by increasing membrane fluidity at low temperatures by incorporating cholesterol or unsaturated lipids into the membrane. Different concentrations of cholesterol-loaded cyclodextrins (CLC) and lipid-loaded cyclodextrins (LLC) containing 1,2-dilinoleoyl-sn-glycero-3-phosphocholine; 1,2-dilinoleoyl-rac-glycerol; and 1,2-dilinolenoyl-sn-glycero-3-phosphocholine were added to rooster sperm to determine if they improved cryopreservation. Osmotic stresses when cryoprotectants (CPA) are added to the cells before freezing and when the CPA are removed from cells after thawing also cause membrane damage. To minimize this damage, low molecular weight CPA with high membrane permeability were tested to determine their effectiveness for cryopreserving sperm. Rooster semen was collected from several birds, pooled and diluted to 800 million sperm mL–1 at 5°C in Lake's Low Temperature diluent (LLT). Sperm were treated with either LLC (0.25, 0.5, 1, 1.5, 2, 4 and 6 mg mL–1) or CLC (0.5, 1 and 2 mg mL–1) for 30 min. The sperm were diluted 1:1 with LLT containing 18% CPA, resulting in final CPA concentrations of 9%. The CPA tested were glycerol (G), methylacetamide (MA), dimethylformamide (DMF), methylformamide (MF) and ethylene glycol (EG). The sperm were frozen in liquid nitrogen vapor and stored in liquid nitrogen. Straws were thawed in 5°C water and sperm motility and membrane integrity analysed immediately. Sperm motility was measured using computer-assisted sperm analysis (CASA) and membrane integrity was analysed by flow cytometry using propidium iodide to detect cells with damaged membranes. Data were analysed by ANOVA and means separated using Student–Newman–Keuls multiple comparison test. Addition of LLC and CLC did improve sperm cryosurvival rates (P > 0.05). Using G as the CPA resulted in higher percentages of motile (54%) and viable (58%) sperm than MA (47 and 52%; P < 0.05), whereas DMF, EG and MF resulted in less than 45% motile cells (P < 0.05). In conclusion, altering sperm membrane composition using CLC and LLC did not improve post-thaw motility or viability in rooster sperm. Although MA did not protect the rooster sperm from cryodamage as effectively as G, future assays will need to determine the fertilizing capacity of sperm frozen using these CPA. We thank CSU-CVBMS for funding support.

scholarly journals Towards the elimination of ergot alkaloid biosynthesis genes in Neotyphodium Coenophialum

2007 ◽  
Vol 13 ◽  
pp. 477-479
Author(s):  
S. Florea ◽  
C. Machado ◽  
D. Zhang ◽  
D.G. Panaccione ◽  
C.L. Schardl
Keyword(s):  
Tall Fescue ◽  
Ergot Alkaloid ◽  
Festuca Arundinacea ◽  
Ergot Alkaloids ◽  
Loxp Site ◽  
Alkaloid Biosynthesis ◽  
Neotyphodium Coenophialum ◽  
Type Locus ◽  
Dimethylallyltryptophan Synthase ◽  
Recombination System

Neotyphodium coenophialum strain e19 from tall fescue cv. Kentucky 31 carries dmaW1 and dmaW2, two gene homologues that encode dimethylallyltryptophan synthase, the enzyme for the first step in ergot-alkaloid biosynthesis. In our effort to disrupt both homologues and ultimately obtain marker-free mutants, we are using a marker-exchange strategy employing the Cre/ loxP site-specific recombination system. Of 1522 transformants obtained and screened, three were likely dmaW2 disruptants because they gave no PCR product from the wild-type locus, but yielded the larger PCR fragment from the disruption construct. The putative dmaW2-knockouts were also transformed with pKAES186, a plasmid with a cassette containing the cre and ble genes in between loxP sequences. The transformants obtained were screened for the presence of hph, cre and ble genes. The preliminary results indicate a loop-out of the hph gene. The transformants inoculated into endophyte-free tall fescue preserved their compatibility with the plant. The fungus grown from these plants will be further analysed for the presence of hph, cre and ble genes. Keywords: Cre/LoxP, dimethylallyltryptophan synthase, dmaW, Epichloë, ergot alkaloids, Festuca arundinacea, gene knockouts, Lolium arundinaceum, Neotyphodium coenophialum, tall fescue

scholarly journals Growth Responses of Hybrid Bluegrass and Tall Fescue as Influenced by Light Intensity and Trinexapac-ethyl

HortScience ◽  
2015 ◽  
Vol 50 (8) ◽  
pp. 1241-1247 ◽  
Author(s):  
Meghyn Meeks ◽  
Ambika Chandra ◽  
Ben G. Wherley
Keyword(s):  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Poa Pratensis ◽  
Block Design ◽  
Kentucky Bluegrass ◽  
Late Spring ◽  
Healthy Plant ◽  
Growth Responses ◽  
Leaf Elongation ◽  
Turfgrass Quality

Interspecific hybrids between texas bluegrass (Poa arachnifera Torr.) and kentucky bluegrass (Poa pratensis L.) are known to exhibit good heat tolerance, which has aided in their adaptation to the warmer climates of the southern United States, but their tolerance to shade has not been investigated. The objectives of this study were to 1) evaluate the growth responses of interspecific bluegrass hybrids (P. arachnifera × P. pratensis) in comparison with kentucky bluegrasses and a shade-tolerant cultivar of tall fescue (Festuca arundinacea Schreb.) under full sunlight and shaded environments, 2) identify optimum times to evaluate shade tolerance using the selected growth measurements, 3) calculate the minimum daily light requirements to retain acceptable turfgrass quality, and 4) determine if trinexapac-ethyl (TE) applications enhance hybrid bluegrass quality under shade. Two 10-week greenhouse experiments (late spring and early fall) were conducted in Dallas, TX. Within each of three light environments a randomized complete block design was used to accommodate three replications of eight genotypes treated with and without TE (0 or 0.228 kg·ha−1 a.i.). Turfgrass quality, leaf elongation rates, clipping dry weights, and percent green cover were measured. Meaningful comparisons were best during the late spring when daily light integrals (DLI) were optimum for healthy plant growth. Shade-tolerant hybrid bluegrasses (DALBG 1201 and TAES 5654) were identified using turfgrass quality and leaf elongation rates. These genotypes exhibited above-acceptable turfgrass quality in all environments, and a reduced leaf elongation rate similar to the tested dwarf-type tall fescue. DLI requirements of DALBG 1201 and TAES 5654 were ≤4 to achieve acceptable quality. TE applications generally did not improve turfgrass quality of genotypes, although leaf elongation rates were significantly reduced in all environments.

181 FERTILIZATION CHARACTERISTICS OF SPERMATOZOA FROM BULLS GRAZING TALL FESCUE PASTURES

2012 ◽  
Vol 24 (1) ◽  
pp. 202
Author(s):  
J. P. Harris ◽  
J. L. Edwards ◽  
L. A. Rispoli ◽  
R. R. Payton ◽  
N. R. Rohrbach ◽  
...  
Keyword(s):  
Tall Fescue ◽  
Ergot Alkaloid ◽  
Mixed Models ◽  
Semen Analysis ◽  
Stress Test ◽  
In Vitro Assays ◽  
Serum Prolactin ◽  
Computer Assisted ◽  
In Vitro Production

Fertilization with spermatozoa from bulls ingesting elevated concentrations of ergovaline [i.e. consumption of toxic endophyte-infected (E+) tall fescue] results in reduced cleavage rates. Thus, the objectives of the current study were to evaluate motility and penetration rates of spermatozoa from bulls grazing tall fescue pastures and intracellular calcium (Ca2+) parameters of presumptive zygotes (PZ). During a 3-month study, 6 Angus bulls (average age = 15.1 ± 0.04 months) were appointed to graze Kentucky 31 tall fescue (Festuca arundinacea Schreb.) infected with Neotyphodium coenophialum, an ergot alkaloid-producing endophyte (n = 3), or Jesup tall fescue infected with non-ergot alkaloid-producing endophyte (NTE) MaxQ™ (n = 3). Bulls were grouped by bodyweight (BW) and scrotal circumference (SC) to graze pastures from April 18 to June 26. Blood samples, BW, SC, semen and rectal temperatures (RT) were collected every 7 days. Semen was evaluated for gross motility, morphology and computer assisted semen analysis (CASA) parameters. Semen from a subset of bulls (n = 2 per treatment; acceptable motility after 3-h stress test) was used to assess spermatozoa function using in vitro assays; that is, in vitro production of embryos, penetration rates obtained 6.5 to 7.5 h post-insemination (hpi) and intracellular Ca2+ measured 8.0 to 10.0 hpi. Data were analyzed using a mixed models procedure (semen data), generalized linear mixed models (in vitro data) and nonlinear regression (intracellular Ca2+ data) of SAS 9.2 (SAS Institute Inc., Cary, NC, USA). Concentrations of serum prolactin were higher in bulls grazing NTE compared with those of the bulls grazing E+ tall fescue pastures (123.43 ± 9.23 ng mL–1 vs 97.13 ± 9.23 ng mL–1, respectively; P = 0.05). Gross motility of spermatozoa (90.95 ± 2.67% vs 85.62 ± 2.67%, NTE and E+ respectively; P = 0.17) and percent normal morphology (77.14 ± 1.93% vs 77.61 ± 1.93%, NTE and E+ respectively; P = 0.87) before cryopreservation did not differ. However, motility immediately post-thaw (58.27 ± 2.81% vs 43.84 ± 5.30%, NTE and E+, respectively; P = 0.02) and following a 3-h stress test (51.13 ± 3.88% vs 23.33 ± 3.23%, NTE and E+, respectively; P < 0.0001) were decreased for spermatozoa from bulls grazing E+ tall fescue. The percentage of PZ that cleaved was higher for oocytes fertilized with spermatozoa from bulls grazing NTE (76.30 ± 3.93%) compared with that of the bulls grazing E+ tall fescue pastures (58.92 ± 3.9%; P = 0.007; n = 1539 PZ, n = 10 replicates). Penetration rates were higher in oocytes fertilized with spermatozoa from NTE bulls (87.42 ± 1.63%) compared with that of E+ bulls (64.54 ± 3.28%; P < 0.0001; n = 2547 oocytes, n = 33 replicates). Meiotic progression of maternal chromatin was hastened in oocytes penetrated by spermatozoa from bulls grazing E+ compared to that from bulls grazing NTE tall fescue. Intracellular Ca2+ parameters (baseline, P = 0.01; amplitude, P = 0.0002; and area under the curve, P = 0.006) were reduced in PZ fertilized with spermatozoa from E+ bulls (n = 192 oocytes, n = 4 replicates). These findings indicate impaired spermatozoa function in bulls grazing E+ tall fescue pastures that extends beyond gross semen characteristics and may provide direction for future studies.

scholarly journals PSII-3 Effect of molasses-based block supplementation on cattle fed endophyte-infected Tall Fescue (Festuca arundinacea) seed

2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 227-228
Author(s):  
Luis Felipe Barbosa Braga. Feitoza ◽  
Hans Christian Muller ◽  
Tom Williams ◽  
James Drouillard
Keyword(s):  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Fixed Effects ◽  
Treatment Time ◽  
Random Effect ◽  
Positive Control ◽  
Negative Control ◽  
Time Interaction ◽  
Doppler Ultrasound Imaging ◽  
Protein Block

Abstract Ergot-alkaloid toxicosis induces persistent vasoconstriction in cattle, interfering with efficient thermoregulation. Our objective was to evaluate impact of cooked molasses-based block supplements (MBS) on performance and physiological measurements in cattle fed ergot-containing Tall Fescue seed (TFS). Crossbred steers (n = 95; 287 ± 6.4 kg) were blocked by body weight, randomly assigned to individual indoor feeding pens and treatments consisting of: Negative Control (NC; prairie hay only); Positive Control (PC; hay plus TFS); and molasses block treatments fed hay and TFS with ad libitum access to a 38% protein block (CB); 38% protein block containing 0.3% crystalline menthol (MB); or a 38% protein block containing a proprietary blend of mannan oligosaccharide and capsaicin (AB). The TFS was mixed with molasses (9:1), and amount fed was increased gradually at 3-d intervals from 45 to 520 g/animal daily by day 42. Temperature differential between ocular conjunctiva and ear tip (ΔT) was determined weekly using thermographic imaging. Coccigeal vein diameter (CVD) was measured with Doppler ultrasound imaging (DU) on days 63 and 84. Data were analyzed as mixed models with block as a random effect and treatment, time, and treatment by time interaction as fixed effects. Block intakes did not differ among MBS treatments (P > 0.05). Cattle fed MBS had greater ADG, DMI, gain:feed (P < 0.01) compared to NC and PC. For the second half of the study MBS treatments had lower ΔT (P < 0.05). Supplementing cooked molasses-based block supplements low-moisture molasses block can improve performance and potentially enhance peripheral blood irrigation in cattle consuming ergot-infested feeds.

scholarly journals Growth Response of Three Turfgrass Species to Nitrogen and Trinexapac-ethyl in Shade

HortScience ◽  
2005 ◽  
Vol 40 (6) ◽  
pp. 1911-1915 ◽  
Author(s):  
D.S. Gardner ◽  
B.G. Wherley
Keyword(s):  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Block Design ◽  
Acid Ethyl Ester ◽  
Visual Quality ◽  
High Rate ◽  
Yield Reduction ◽  
Neutral Density ◽  
Growth Responses

Previous research on the potential of the gibberellin inhibiting growth regulator trinexapac-ethyl (TE) [4-(cyclopropyl-α-hydroxy-methylene)-3,5-dioxocyclohexanecarboxylic acid ethyl ester] to improve quality and density of shaded turfgrass has been conducted under neutral-density shade. However, some phytochrome-mediated growth responses of turfgrass, such as tillering, are different under deciduous shade versus neutral-density shade. The objectives of this study were to investigate 1) whether TE would result in improved stand density and quality of turfgrass grown under deciduous shade as has been observed under neutral-density shade and 2) the shade tolerance of sheep fescue (Festuca ovina L. `Quatro') compared to tall fescue (Festuca arundinacea Schreb. `Plantation'), and rough bluegrass (Poa trivialis L.). Trinexapac-ethyl at either 0 or 29 kg·ha–1 a.i. and nitrogen at 12 or 36 kg·ha–1 were applied on 23 May, 3 July, and 15 Aug. 2003 and 21 May 2004 to each species in a randomized complete block design under deciduous shade (about 9% of full sun). Clipping yield, color, and density data were collected for 6 weeks after the May applications in each year. Visual quality was assessed for 6 weeks after application in 2004 only. In 2003, TE significantly reduced clipping yields by 35% to 50% on sheep fescue, 58% to 76% on tall fescue and 55% to 80% on rough bluegrass. However, in 2004, yield reduction was 0% to 50% for all three species and there was no interaction between week, TE, and species. `Plantation' tall fescue had the highest overall visual quality and density. Sheep fescue also provided an acceptable quality turf stand. TE application did not significantly impact the quality of these species. Rough bluegrass performance was unacceptable, and high rate applications of TE to this species in shade resulted in significant (P < 0.05) losses in density. Trinexapac-ethyl application, based on the results of this study, may not enhance turf quality of cool season grasses grown under dense tree shade.

12 FERTILITY OF FROZEN EQUINE SPERM IN SYSTEMS FOR CRYOPRESERVATION

2012 ◽  
Vol 24 (1) ◽  
pp. 117
Author(s):  
R. R. D. Maziero ◽  
P. N. Guasti ◽  
I. D. P. Blanco ◽  
I. Martin ◽  
G. A. Monteiro ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Liquid Nitrogen ◽  
Membrane Integrity ◽  
Skim Milk ◽  
Egg Yolk ◽  
Automated System ◽  
Epifluorescence Microscopy ◽  
Computer Assisted ◽  
Plasma Membrane Integrity ◽  
Sperm Analysis

Optimizing cryopreservation of equine sperm will facilitate genetic banking and propagation of important horse strains through assisted reproduction. This study aimed to evaluate the motility pattern using computer-assisted sperm analysis (CASA) and plasma membrane integrity by epifluorescence microscopy of equine semen frozen in 0.5 mL straws at different freezing rates; also, a fertility trial was performed according to the freezing protocol. Three ejaculates from four stallions of various breeds (Mangalarga Marchador, Westfallen, Hanovarian and Arabian) and ages (5 to 20 years) were collected and processed for cryopreservation. The stallions were housed at the CERBEQ, Reproduction Centre of the Department of Animal Reproduction and Veterinary Radiology, UNESP. The ejaculates were filtered and submitted to analysis by CASA (HTM IVOS 12, Hamilton Thorne Research, USA). In addition, the plasma membrane integrity was determined by fluorescent probes. After evaluation, the ejaculates were diluted at 1:1 (extender:semen) with skim milk extender Botu-Semen™ and centrifuged at 600 × g for 10 min. The supernatant was removed and the pellet resuspended to a final concentration of 100 × 106 sperm mL–1 with milk-egg yolk freezing extender (Botu-Crio™). Semen was packaged in 0.5-mL straws (IMV, LAigle, France) and was placed in nitrogen for 20 min and then from room temperature to 5°C and then frozen in two different cooling systems: an isothermic box (42 cm × 28 cm × 12.5 cm) was placed upon racks suspended 6 cm above liquid nitrogen or other 20 min then immersed into nitrogen and automated system Mini Digitcool™ (IMV Technologies, France), cooling at a –40°C min–1 rate. All straws were stored in liquid nitrogen until thawing and analysis. The straws were thawed in a water bath at 46°C for 20 s and the samples were evaluated for progressive motility, angular progressive velocity, progressive velocity, track speed, percentage of rapid sperm and percentage of sperm with plasma membrane integrity. For the fertility trial, 65 clinically healthy mares had their oestrous cycle monitored by ultrasound and inseminated postovulation with sperm into the uterus. Ovulation was induced with 1 mL of deslorelin acetate (GnRH) injected IM when a 35-mm follicle was detected. Thirty-six hours later, mares were monitored every 6 h until ovulation was detected. When it was detected, mares were inseminated with 800 × 106 total sperm. Pregnancy was confirmed via ultrasound examination 15 days after ovulation. Pregnancy rate was 52.2% using the isothermic box and 60% using the automated machine. Statistical analysis from the frozen–thawed semen evaluated parameters was performed using the statistics software Proc. MIXED of SAS 9.1 and for the fertility trial, logistic regression using the Proc GENMOD from SAS 9.1. The conventional method using the isothermic box was similar to the automated machine with a fast freezing rate. Additionally, AI with 800 × 106 sperm frozen in the isothermic box or automated system resulted in similarly acceptable conception rates.

scholarly journals Broad-sense Heritability and Stability Analysis of Brown Patch Resistance in Tall Fescue

HortScience ◽  
2009 ◽  
Vol 44 (2) ◽  
pp. 289-292 ◽  
Author(s):  
Jonathan M. Bokmeyer ◽  
Stacy A. Bonos ◽  
William A. Meyer
Keyword(s):  
Stability Analysis ◽  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Block Design ◽  
Genetic Resistance ◽  
Continuous Distribution ◽  
Field Trials ◽  
Broad Sense ◽  
Broad Sense Heritability ◽  
Brown Patch

Brown patch, caused by Rhizoctonia solani Kühn, is a devastating disease of tall fescue (Festuca arundinacea Schreb.). Developing genetic resistance is a viable long-term control strategy; however, the genetic mechanism of brown patch resistance in tall fescue is not known. The objectives of this study were to determine the broad-sense heritability and stability analysis of brown patch resistance in tall fescue. To complete these objectives, 230 tall fescue genotypes were arranged in a randomized complete block design with six clonal replications at two locations and evaluated for brown patch resistance over 2 years. Two isolates of R. solani were used to inoculate both field trials at a rate of 0.8 g·m−2 of prepared inoculum. The lack of complete resistance and the observation of a continuous distribution of phenotypes suggest that brown patch resistance is quantitatively inherited. The broad-sense heritability estimates (0.25 on a single plant basis and 0.74 on 12-plant clonal mean basis) indicate that resistance is influenced by the genotype and also illustrate the importance of replication in selecting for brown patch resistance in tall fescue. Stability analysis resulted in the identification of tall fescue genotypes that were stable over multiple environments for brown patch resistance.

Isolation and identification of plant growth-promoting bacteria associated with tall fescue

2009 ◽  
pp. 211-216 ◽  
Author(s):  
J. Monk ◽  
E. Gerard ◽  
S. Young ◽  
K. Widdup ◽  
M. O'Callaghan
Keyword(s):  
New Zealand ◽  
Plant Growth ◽  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Plant Growth Promoting Bacteria ◽  
Beneficial Bacteria ◽  
Isolation And Identification ◽  
Naturally Occurring ◽  
Plant Growth Promoting ◽  
Growth Promoting

Tall fescue (Festuca arundinacea) is a useful alternative to ryegrass in New Zealand pasture but it is slow to establish. Naturally occurring beneficial bacteria in the rhizosphere can improve plant growth and health through a variety of direct and indirect mechanisms. Keywords: rhizosphere, endorhiza, auxin, siderophore, P-solubilisation

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