bluuebunny/crossref_metadata_2025 huggingface dataset:
Argon Laser Photocystotomy of a Vitreous Cyst
Authors: Desai Rajen U. , Saffra Norman A.
Published: March 2010

Free-floating idiopathic vitreous cysts are rare entities. For symptomatic patients, treatment options include laser photocystotomy or pars plana vitrectomy (PPV) with cyst excision. Historically, size of the cyst impacted treatment approaches. Laser treatments have been used for smaller cysts ranging 3 to 5 mm in diameter. PPV has been utilized for cysts larger than 4 mm. Successful laser photocystotomy has been reported, utilizing both argon and Nd: YAG lasers. Herein, we present a case of successful argon laser photocystotomy of a 7.1 mm diameter vitreous cyst, the largest documented cyst ever treated. Treatment should be individualized based on patient age, ability to cooperate in an office setting, phakic status, status of the posterior hyaloid, cyst morphology, and location. In our case, because of pigment on the anterior cyst surface, and the presence of an attached posterior hyaloid, the argon green laser was used.
A Rare Presentation of Occult Sinusitis: Upper Eyelid Fistula
Authors: Narendran Nirodhini , Sandramouli Soupramaniem
Published: March 2010

Sinus disease can present in a variety of ways and may occur in individuals who are not otherwise aware that they have problems (occult sinusitis). An unusual presentation of occult frontal sinus disease in a 64-year-old patient was reported. A fistulous communication with the upper lid, causing a persistent abscess. There was a 6-month delay in making the correct diagnosis and the patient was treated with repeated courses of antibiotics and even an incision and drainage procedure. Finally, the correct diagnosis was made following CT imaging and the patient underwent functional endoscopic sinus surgery which closed the communication, but left the patient with a tight upper lid, which required further oculoplastic surgery. The patient was pleased with the final visual outcome and the fistula remained closed.
Pupillary Block Glaucoma After Implantation of Iris-Fixated Phakic Intraocular Lens
Authors: Okumura Yoshihiko , Yamaguchi Takefumi , Shiba Daisuke , Murat Dogru , Kawamura Ryosuke , Toda Ikuko , Tsubota Kazuo , Negishi Kazuno
Published: March 2010

To report a case of pupillary block glaucoma after implantation of iris-fixated phakic intraocular lens (IF pIOL). A 43-year-old man was referred for pupillary block one day after implantation of IF pIOL. Slit-lamp examination revealed extremely shallow anterior chamber, closure of peripheral laser iridotomy and contact of iris on the peripheral of the optics of IF pIOL. The intraocular pressure (IOP) was 62 mm Hg. The iris moved forward in contact with the IF pIOL and the lens remained in the physiologic position, which made the distance between the lens and the iris wide. He underwent an uneventful peripheral surgical iridectomy and the IOP decreased to 6 mm Hg. Acute pupillary block glaucoma can occur after IF pIOL implantation due to the occlusion of aqueous flow between the IF pIOL and the iris if the peripheral iridotomy closes.
Fundus Autofluorescence Imaging of Diffuse Uveal Melanocytic Proliferation
Authors: Semenova Ekaterina A. , Chin Kimberly J. , Natesh Sribhargava , Finger Paul T.
Published: March 2010

Fundus autofluorescence imaging (FAF) in a case of diffuse uveal melanocytic proliferation is described in this study. It is a rare chorioretinopathy associated with systemic cancer, for which the exact pathological mechanisms are poorly understood. FAF-imaging revealed a diffuse background of hyper-autofluorescence associated with diffuse orange pigment deposition and islands of persistent hypo-fluorescence corresponding to loss of retinal pigment epithelium (RPE). In this disorder, increasingly smaller spots of FAF hypo-fluorescence were found from the center to the periphery of the affected retina. Fluorescein angiography demonstrated a negative of the FAF-images. FAF hypo-autofluorescence corresponded to optical coherence tomography (OCT) thinning or absence of the RPE-layer. Conversely, FAF hyper-autofluorescence correlated to thickening of the RPE-layer on OCT. The case demonstrates that FAF can be useful for the diagnosis of diffuse uveal melanocytic proliferation and offers greater insight into the pathophysiology of this disease.
In Vivo Confocal Microscopy in Presumed Central Cloudy Dystrophy of François
Authors: Utine Canan Asli , Oral Deniz , Altunsoy Muhsin , Basar Demir , Alimgil Levent M.
Published: March 2010

A 70-years-old woman with no visual symptoms was incidentally diagnosed with presumed central cloudy dystrophy of François (CCDF) on regular ophthalmic examination. Bilateral polygonal opacities separated by clear spaces were seen in corneal biomicroscopic examination. The opacities were prominent in the central cornea and occupied full-thickness corneal stroma. Confocal microscopy revealed small highly refractile granules and deposits in the anterior and deeper stromal layers. Multiple dark acellular striae among extra-cellular matrices with increased intensities were seen in the posterior stroma. No stromal layer of keratocytes was observed. In the right eye, the corneal endothelial cell density was 3,319 cells/mm
2
, polymegathism was 52.9%, and pleomorphism was 34.3%. In the left eye, endothelial cell counts could not be performed because of high stromal reflectance intensity. Full-thickness involvement of the corneal stroma with hyperreflective granules and microstriae and absence of keratocytes may represent a more advanced stage of the dystrophy.
Severe Hypotony Associated With Parry–Romberg Syndrome
Authors: Hung Susan , Rutar Tina , Lin Shan , Wong Ira G.
Published: March 2010

Parry–Romberg syndrome is a rare inflammatory disorder characterized by progressive hemifacial atrophy and ocular involvement. Two patients with Parry–Romberg syndrome who had mild heterochromic uveitis but developed profound ocular hypotony were evaluated. A 17-year-old girl and a 32-year-old woman with Parry–Romberg syndrome developed chronic uveitis with gradual worsening of intraocular pressure to 0 mm Hg. For the first time, ultrasound biomicrosopy found evidence of inflammation of the ipsilateral ciliary muscle in patients with hemifacial atrophy. The profound hypotony concomitant with ciliary body edema in two patients with Parry–Romberg syndrome provides a clue linking the systemic disease to the ocular findings.
Unusual Loop-Like Vessel Formation After Intravitreal Ranibizumab Injections in AMD
Authors: Koizumi Hideki , Ferrara Daniela C. , Slakter Jason S.
Published: March 2010

The authors observed an unusual closed loop-like vessel formation in the macula and describe its regression caused by the heterogenous treatment effects of intravitreal ranibizumab injections in an eye with exudative age-related macular degeneration associated with multiple retinochoroidal anastomoses.
Acute Phthisis Bulbi in a Premature Infant
Authors: Moss Jason , Jain Atul , Doshi Amish , Moshfeghi Darius M.
Published: March 2010

A neonate with an estimated gestational age of 32 weeks who had post-partum sepsis (methicillin-resistant
Staphylococcus aureus
[MRSA] and
Pseudomonas aeruginosa
) and MRSA meningitis was found to have blunted light reflexes and microphthalmia in both eyes on routine screening for retinopathy of prematurity. Retrolenticular membranes precluded visualization of the fundi. Computed tomography confirmed the presence of intraocular calcifications, an interval development over 6 weeks from previously normal scans. Referral was made and diagnostic enucleation of the right eye was performed, revealing intraocular disorganization and metaplasia consistent with phthisis following intraocular inflammation. The patient's contralateral eye achieved visual acuity of light perception after lensectomy and vitrectomy. Vitreous cultures from the enucleation specimen and from the fellow eye at the time of vitrectomy were negative. Unsuspected, untreated endogenous endophthalmitis can result in dramatic and rapid metaplastic response in the developing eye and result in acute phthisis.
Fundus Autofluorescence and OCT in the Management of Progressive Outer Retinal Necrosis
Authors: Yeh Steven , Wong Wai T. , Weichel Eric D. , Lew Julie C. , Chew Emily Y. , Nussenblatt Robert B.
Published: March 2010

A 41-year-old woman with AIDS presented with progressive nasal visual field loss in her right eye. Ophthalmic examination revealed widespread retinal opacification with hemorrhage consistent with progressive outer retinal necrosis, which was confirmed by polymerase chain reaction for varicella zoster virus DNA. The patient was treated with intravenous and intravitreal foscarnet and ganciclovir with improvement clinically. Optical coherence tomography (OCT) and fundus autofluorescence imaging revealed progressive changes indicative of widespread retinal pigment epithelial (RPE) and outer retinal dysfunction. OCT showed progressive changes in macular architecture, including neurosensory elevation, cystoid macular edema, and severe outer retinal necrosis, at initial examination and 1 week and 1 month of follow-up. Fundus autofluorescence revealed stippled hyperfluorescence within extensive zones of hypofluorescence, which progressed during follow-up. OCT and fundus autofluorescence was useful in the characterization of the RPE and retinal anatomy in this patient with progressive outer retinal necrosis.
Mitochondrial Reactive Oxygen Species Control T Cell Activation by Regulating IL-2 and IL-4 Expression: Mechanism of Ciprofloxacin-Mediated Immunosuppression
Authors: Kamiński Marcin M. , Sauer Sven W. , Klemke Claus-Detlev , Süss Dorothee , Okun Jürgen G. , Krammer Peter H. , Gülow Karsten
Published: March 2010

This article shows that T cell activation-induced expression of the cytokines IL-2 and -4 is determined by an oxidative signal originating from mitochondrial respiratory complex I. We also report that ciprofloxacin, a fluoroquinolone antibiotic, exerts immunosuppressive effects on human T cells suppressing this novel mechanism. Sustained treatment of preactivated primary human T cells with ciprofloxacin results in a dose-dependent inhibition of TCR-induced generation of reactive oxygen species (ROS) and IL-2 and -4 expression. This is accompanied by the loss of mitochondrial DNA and a resulting decrease in activity of the complex I. Consequently, using a complex I inhibitor or small interfering RNA-mediated downregulation of the complex I chaperone NDUFAF1, we demonstrate that TCR-triggered ROS generation by complex I is indispensable for activation-induced IL-2 and -4 expression and secretion in resting and preactivated human T cells. This oxidative signal (H2O2) synergizes with Ca2+ influx for IL-2/IL-4 expression and facilitates induction of the transcription factors NF-κB and AP-1. Moreover, using T cells isolated from patients with atopic dermatitis, we show that inhibition of complex I-mediated ROS generation blocks disease-associated spontaneous hyperexpression and TCR-induced expression of IL-4. Prolonged ciprofloxacin treatment of T cells from patients with atopic dermatitis also blocks activation-induced expression and secretion of IL-4. Thus, our work shows that the activation phenotype of T cells is controlled by a mitochondrial complex I-originated oxidative signal.
CCR5 Dictates the Equilibrium of Proinflammatory IL-17+ and Regulatory Foxp3+ T Cells in Fungal Infection
Authors: Kroetz Danielle N. , Deepe George S.
Published: March 2010

CCR5 is a chemotactic mediator for inflammatory cells as well as regulatory T cells (Tregs). In this study, we investigated the role of CCR5 during infection with the fungal pathogen Histoplasma capsulatum. Mice lacking CCR5 or treated with an mAb to CCL4 had impaired infiltration of inflammatory cells to the lungs. Despite displaying an elevated fungal burden prior to activation of an adaptive immune response, CCL4-neutralized and CCR5−/− mice resolved infection more efficiently than controls. Accelerated fungal clearance was associated with a reduced number of Tregs in the lungs. Impaired trafficking was not solely responsible for the paucity of Tregs in the lungs, as proliferation of both CD4+ T cells and Tregs was diminished in CCR5−/− lungs during infection. A reduced number of Tregs in CCR5−/− lungs was associated with a selective increase of Th17 cytokines, and neutralization of IL-17 increased Treg proliferation and consequently fungal burden in CCR5−/− mice. Thus, CCR5 dictates pathogen persistence by tightly regulating the balance between Treg and Th17 cells in H. capsulatum infection.
Statins Decrease Oxidative Stress and ICD Therapies
Authors: Bloom Heather L. , Shukrullah Irfan , Veledar Emir , Gutmann Rebecca , London Barry , Dudley Samuel C.
Published: March 2010

Recent studies demonstrate that statins decrease ventricular arrhythmias in internal cardioverter defibrillator (ICD) patients. The mechanism is unknown, but evidence links increased inflammatory and oxidative states with increased arrhythmias. We hypothesized that statin use decreases oxidation.Methods.304 subjects with ICDs were surveyed for ventricular arrhythmia. Blood was analyzed for derivatives of reactive oxygen species (DROMs) and interleukin-6 (IL-6).Results.Subjects included 252 (83%) men, 58% on statins, 20% had ventricular arrhythmias. Average age was 63 years and ejection fraction (EF) 20%. ICD implant duration was 29±27 months. Use of statins correlated with lower ICD events (r=0.12,P=.02). Subjects on statins had lower hsCRP (5.2 versus 6.3;P=.05) and DROM levels (373 versus 397;P=.03). Other factors, including IL-6 and EF did not differ between statin and nonstatin use, nor did beta-blocker or antiarrhythmic use. Multivariate cross-correlation analysis demonstrated that DROMs, statins, IL-6 and EF were strongly associated with ICD events. Multivariate regression shows DROMs to be the dominant predictor.Conclusion.ICD event rate correlates with DROMs, a measure of lipid peroxides. Use of statins is associated with reduced DROMs and fewer ICD events, suggesting that statins exert their effect through reducing oxidation.
Identification, Cloning, and Characterization of l-Phenylserine Dehydrogenase from Pseudomonas syringae NK-15
Authors: Ueshima Sakuko , Muramatsu Hisashi , Nakajima Takanori , Yamamoto Hiroaki , Kato Shin-ichiro , Misono Haruo , Nagata Shinji
Published: March 2010

The gene encoding d-phenylserine dehydrogenase from Pseudomonas syringae NK-15 was identified, and a 9,246-bp nucleotide sequence containing the gene was sequenced. Six ORFs were confirmed in the sequenced region, four of which were predicted to form an operon. A homology search of each ORF predicted that orf3 encoded l-phenylserine dehydrogenase. Hence, orf3 was cloned and overexpressed in Escherichia coli cells and recombinant ORF3 was purified to homogeneity and characterized. The purified ORF3 enzyme showed l-phenylserine dehydrogenase activity. The enzymological properties and primary structure of l-phenylserine dehydrogenase (ORF3) were quite different from those of d-phenylserine dehydrogenase previously reported. l-Phenylserine dehydrogenase catalyzed the NAD+-dependent oxidation of the β-hydroxyl group of l-β-phenylserine. l-Phenylserine and l-threo-(2-thienyl)serine were good substrates for l-phenylserine dehydrogenase. The genes encoding l-phenylserine dehydrogenase and d-phenylserine dehydrogenase, which is induced by phenylserine, are located in a single operon. The reaction products of both enzymatic reactions were 2-aminoacetophenone and CO2.
THE EFFECT OF SHADE STRESS ON THE PERFORMANCE OF CORN FOR SILAGE VERSUS GRAIN
Authors: MBEWE D. M. N. , HUNTER R. B.
Published: March 2010

A field study was conducted near Guelph, Ontario, to investigate the effects of shade stress on the yield of corn grown for silage versus grain. The effects of shading on the quality of whole-plant corn silage were also examined. Shade was provided by two layers of fiberglass screen, which reduced the amount of light by approximately 65%. The shade treatments were applied during either the vegetative, reproductive or grain-filling stages of development. Shading at any stage reduced whole-plant dry matter (WPDM) yield at the silage corn harvest stage and the level of this reduction was relatively independent of the stage at which the shade was applied. Grain DM yield at the grain harvest stage was also reduced by light stress, with the greatest reduction resulting from light stress during the reproductive stage. However, for silage production, high stover yield compensated for the reduction in grain yield, resulting in little reduction in whole-plant yield. Shading during either the reproductive or filling stage reduced WPDM content due to reduced grain content and higher stover moisture content.Key words: Corn, silage quality, whole-plant corn silage
EFFECT OF SEEDING RATE ON HEIGHT, YIELD AND QUALITY OF LARGE-SEEDED AND SEMI-DWARF BUCKWHEAT GENOTYPES
Authors: GUBBELS G. H. , CAMPBELL C. G.
Published: March 2010

Two large-seeded buckwheat (Fagopyrum esculentum Moench.) cultivars, Mancan and Manor, and semi-dwarf lines, were grown at Morden and Portage la Prairie in the years 1979–1982 at seeding rates of 15, 30, 45 and 60 kg/ha. There was no consistent effect of seeding rate on plant height, seed weight (g/1000 seeds) or seed density. In six of the eight location-years there was no interaction of genotype × seeding rate for seed yield, indicating that, generally, the cultivars and lines reacted similarly to differences in seeding rate. It was concluded that a seeding rate of from 30 to 45 kg/ha would ensure optimum yield in most years.Key words: Buckwheat, Fagopyrum esculentum Moench., seeding rates
EFFECT OF KERNEL WATER CONCENTRATION AT HARVEST AND DRYING METHOD ON GRADES OF RED SPRING AND DURUM WHEATS
Authors: CLARKE JOHN M.
Published: March 2010

Effects of kernel water concentration at harvest, and windrow compared to artificial drying, were determined in two red spring (Triticum aestivum L.) and three durum (T. turgidum L. var. durum) cultivars. Grain harvested at kernel water concentrations of 1000 to < 170 g water per kilogram kernel dry weight was dried in the field in simulated windrows or artificially in a forced-air oven (40–45 °C). Test weight and commercial grades were determined. Artificial drying of immature wheat reduced grades, primarily due to numbers of green kernels. Green kernel levels reduced grades of windrowed durum wheat in 1 of 3 years. In the absence of grade-limiting levels of green kernels, test weight limited grades of durum in 1 year, particularly in the windrowed treatment. In a separate experiment, percentages of green kernels were determined in field-scale windrowed and standing hard red spring and durum wheat crops. Levels of green kernels declined at similar rates in standing and windrowed crops. The kernel water concentration at which level of green kernels dropped to 0.75%, the maximum level tolerated in the top grades of hard red spring and durum wheat, was lower in dry years when maturity was forced than in moist years.Key words: Wheat (red spring), wheat (durum), windrowing, artificial drying, test weight
SAINFOIN ESTABLISHMENT AND PRODUCTION ON TRIFLURALIN-TREATED SOILS, AND HERBICIDE RESIDUES IN GREEN FORAGE AND HAY
Authors: WADDINGTON JOHN , CESSNA ALLAN J. , MOYER JAMES R. , HOLT NEAL W.
Published: March 2010

Sainfoin (Onobrychis viciaefolia Scop.) was grown in soils treated with 1.12 and 2.24 kg a.i./ha of trifluralin at four sites in western Canada. Sainfoin seedling populations were reduced only on a soil very low in both organic matter and clay. Weed control by trifluralin applied at 1.12 kg/ha resulted in dry matter yields equal to those from handweeded plots in both the seedling years and the following year. Forage yields were reduced at one site treated with 2.24 kg/ha of trifluralin. A method for extracting and measuring trifluralin residues in green and dried forage is described. Trifluralin residues in sainfoin forage samples harvested in the fall of the seedling year were not significantly different at three sites from the background level of 0.6 ± 0.4 ppb and were 3.6 ± 0.7 ppb for the fourth site. All the residue levels were below the limit of reliable measurement of the analytical method. It was demonstrated that sainfoin can be established reliably in soils treated with 1.12 kg a.i./ha of trifluralin just prior to seeding, and that trifluralin residues are negligible by the time a harvestable amount of forage has been produced.Key words: Sainfoin, Onobrychis viciaefolia, trifluralin, residues, tolerance, yield
FEASIBILITY OF PRODUCTION OF COMMERCIAL HYBRIDS IN REED CANARYGRASS, Phalaris arundinacea L., USING A YELLOW-SEEDED MUTANT
Authors: KNOWLES R. P.
Published: March 2010

A yellow-seeded mutant of reed canarygrass resulting from close breeding was used to produce F1 hybrids with normal black-seeded strains. The vigor of the yellow-seeded parent was below that of standard cultivars but seed yield was significantly higher. Forage yields of hybrids from the free interpollination with black-seeded strains were equal to, but not above, those of recommended cultivars. A high degree of effective hybridization (80% or more) was obtained when sib lines, selfed lines, or synthetics of the yellow-seeded mutant were grown in alternate rows with black-seeded strains. Alternate three-row (3 m) groups of parents in the hybrid crossing block were convenient for machine harvesting of seed and resulted in good hybridization.Key words: Reed canarygrass, heterosis, incompatibility, seed production, pollination
EFFECT OF DEFOLIATING TIMOTHY CULTIVARS DURING PRIMARY GROWTH ON YIELD, QUALITY AND PERSISTENCE
Authors: KUNELIUS H. T. , McRAE K. B.
Published: March 2010

A forage system based on timothy (Phleum pratense L.) cultivars of different maturities is recommended in Atlantic Canada. Early and later maturing cultivars are grown to spread the harvesting of timothy, at optimal primary growth maturities, to about 3 wk. At some locations the resulting harvest period has been considerably shorter and for this reason the timothy system was examined in a 4-yr field study. Four timothies, representing very early, early, midseason, and late cultivars, were cut at five dates with primary growth stages ranging from vegetative to full heading. Regrowth was cut about 45 days after cut 1. Total dry matter yield and total N concentration of combined cuts 1 and 2 were generally influenced by cutting schedules but not by cultivars. The in vitro dry matter disappearance (IVDMD) was dependent on both cutting schedule and cultivar. The early-maturing cultivar Clair reached its peak IVDMD earlier than later maturing Champ, Itasca, or Bounty. At termination of the field study, there were fewer timothy tillers per square metre and ground cover by timothy was slightly less for those cuts taken during stem elongation. The results suggest that three out of four cultivars were of similar maturity and had similar total N and IVDMD. We conclude that the currently recommended timothy cultivars in Atlantic Canada do not provide a sufficient range in maturity for the average growing season in the region to warrant multiple cultivars on individual farms. At present, timothy stands may be cut prior to and during stem elongation to lengthen the harvest period.Key words: Timothy, in vitro dry matter digestibility, total nitrogen
TOLERANCE OF EARLY-MATURING SOYBEAN CULTIVARS TO METRIBUZIN
Authors: FRIESEN G. H. , WALL D. A.
Published: March 2010

McCall, Maple Presto, Maple Amber and OT80-3 soybean (Glycine max (L.) Merr.) cultivars were evaluated under field conditions for their response to metribuzin. Maple Amber was found to be less tolerant than the other cultivars. In controlled environment chamber studies, injury to this cultivar was more severe on a sandy loam soil than on a clay loam soil. Fall applications of metribuzin, alone or tank-mixed with trifluralin, were tolerant to Maple Amber soybeans and such applications may offer a practical alternative to spring treatments for broad spectrum weed control in the less tolerant soybean cultivars grown in Manitoba.Key words: Metribuzin, trifluralin, preplant incorporation, fall treatments, soybean cultivars
FABA BEAN AS FORAGE IN THE PARKLANDS OF ALBERTA
Authors: BERKENKAMP B. , MEERES J.
Published: March 2010

Six cultivars of faba bean were compared for forage yield over 3 years at two locations, on Black and Grey-wooded soils. Aladin, Herz Freya and Outlook were more productive than the earlier maturing Diana, or the very early Lacombe lines. Protein averaging 18.8% resulted in very high protein production.Key words: Faba bean, Vicia faba, forage
EFFECTS OF FREQUENCY OF IRRIGATION ON NUTRIENT UPTAKE OF APPLE TREES
Authors: NEILSEN G. H. , STEVENSON D. S.
Published: March 2010

Throughout the 1980–1983 growing seasons, ’Summerland Red McIntosh’ apple (Malus domestica Borkh.) on M.26 rootstock growing outdoors in large buried pots with a range of N nutrition were irrigated daily or twice weekly with the same quantity of water (equivalent to 5.9 mm∙day−1) Irrigation frequency affected leaf nutrient concentration; leaf Mn and Zn increased in 3 of 4 yr, leaf Ca and Mg in 2 yr and leaf N in 1 yr at the daily irrigation frequency.Key words: Irrigation frequency, McIntosh apple trees, leaf N, leaf Ca, leaf Mg, leaf Zn, leaf Mn
CONTROL OF WILD OAT WITH TRIALLATE IN A SPRING WHEAT CONSERVATION TILLAGE SYSTEM
Authors: CARLSON S. J. , MORROW L. A.
Published: March 2010

Triallate granules were applied at 2.8 kg/ha without incorporation either immediately before or after planting into standing spring wheat (Triticum aestivum L. ’Fielder’ and ’Dirkwin’) stubble. The triallate granules controlled wild oat (Avena fatua L.), and resulted in increased spring wheat yield. Difenzoquat or diclofop-methyl application also increased wheat yields.Key words: Triallate, oat (wild), conservation tillage, minimum tillage, wheat (spring)
QUACKGRASS COMPETITION EFFECT ON POTATO YIELD
Authors: IVANY J. A.
Published: March 2010

The effect of different periods of quackgrass (Agropyron repens L. Beauv.) competition after crop emergence was studied for potato (Solanum tuberosum L. ’Russet Burbank’). Delaying quackgrass removal for 2 wk after crop emergence reduced small-sized tuber yield, marketable tuber yield and total yield by 6%, 27% and 21%, respectively, averaged over 4 yr. Successively longer delays in quackgrass removal showed progressively greater reductions in yield.Key words: Quackgrass, potato, competition
CANDEL FLUE-CURED TOBACCO
Authors: PANDEYA R. S.
Published: March 2010

Candel flue-cured tobacco (Nicotiana tabacum L.) with good quality of cured leaves, lower smoke tar:nicotine ratio and early maturing habits was developed at the Agriculture Canada Research Station, Delhi, Ontario in an interspecific hybridization study.Key words: Tobacco, Tar:nicotine ratio, cultivar description
INFLUENCE OF TEMPERATURE ON STERILITY OF TWO CYTOPLASMIC MALE-STERILITY SYSTEMS IN RAPE (Brassica napus L.)
Authors: FAN ZHEGONG , STEFANSSON B. R.
Published: March 2010

The effect of temperature on two cytoplasmic male-sterility (CMS) systems in rape (Brassica napus L.) was investigated. These were the nap CMS system with cytoplasm which occurs in most Canadian cultivars and the pol CMS system with cytoplasm from the cultivar Polima. The day/night temperature regimes used were 22/16, 26/20 and 30/24 °C. Two floral characteristics, anther type and stamen length, were influenced by temperature treatments. Male sterility of both CMS systems was expressed consistently at the lowest temperature. The nap male-sterile plants became partially sterile at the second temperature and fully fertile at the highest temperature. The pol male-sterile plants were more stable and became partially sterile only at the highest temperature.Key words: Rape, Brassica napus L., CMS, temperature
VARIATION IN DIGESTIBILITY DECLINE WITH ADVANCE IN MATURITY AMONG TIMOTHY (Phleum pratense L.) GENOTYPES
Authors: McELROY A. R. , CHRISTIE B. R.
Published: March 2010

The in vitro digestibility (IVD) of timothy (Phleum pratense L.) declines with advance in maturity. Forage quality reductions resulting from late harvesting could be minimized by developing cultivars with reduced IVD decline during maturation. This study examines variation for IVD decline among timothy genotypes. Clones originating from a single population were grown in simulated swards (100 plants m−2) at two Ontario locations in 1980 and 1981. Harvests were made every 5–6 d from early heading to late anthesis. Relative IVD declines were determined by regressing genotype performance on the population mean over several harvests. Considerable variation was found for relative IVD decline, but this parameter was not associated with IVD at early heading. Genotypes were identified which showed high IVD at heading and a 20% reduction in digestibility decline from heading to late anthesis. Changes in IVD were not associated with changes in the leaf content of forage. It is concluded that selection for reduced IVD decline, in addition to high digestibility at heading, might result in a 2–3% unit increase at anthesis.Key words: Timothy, Phleum pratense L., in vitro digestibility, IVD, IVD decline
EVALUATION OF TWO DOLLARSPOT FORECASTING SYSTEMS FOR CREEPING BENTGRASS
Authors: BURPEE L. L. , GOULTY L. G.
Published: March 2010

Dollarspot, caused by Lanzia sp. and/or Moellerodiscus sp., is a serious disease of turfgrass in cool humid climates. Fungicide application programs, based on the Hall and Mills and Rothwell (M & R) dollarspot forecasting systems for creeping bentgrass (Agrostis palustris Huds.), were compared with fungicide application schedules of 7, 14 and 21 d in 1983 and a schedule of 10 d in 1984. In both years, programs based on the Hall system failed to provide acceptable disease control (< 1 dollarspot m−2 of turf) with chlorothalonil applied at 5.7 kg a.i. ha−1. In 1983, the same dosage of chlorothalonil applied according to the M & R system or a 7-d spray schedule resulted in acceptable disease control over a 70-d test period. Spray schedules of 14 and 21 d did not provide acceptable control. In 1984, the M & R system and a 10-d spray schedule resulted in significant disease control over a 44-d test period. Increases in the incidence of dollarspot were observed on 20 and 18 d in 1983 and 1984, respectively. The M & R system’s critical weather criteria, used to select the time for fungicide applications, were met on 48 and 35 d in 1983 and 1984, respectively. This overestimation of disease indicated that the success of the M & R system was a result of prediction frequency and not prediction accuracy. Failure of the Hall system was attributed to its ability to predict disease on only 17% of the occasions when increases in disease incidence were observed.Key words: Disease management, fungicide, turfgrass, dollarspot
LANCER HARD RED SPRING WHEAT
Authors: PAUW R. M. DE , TOWNLEY-SMITH T. F. , CLARKE J. M. , McCAIG T. N. , McBEAN D. S.
Published: March 2010

Lancer hard red spring wheat (Triticum aestivum L.) combines a high level of stem solidness which confers resistance to wheat stem sawfly (Cephus cinctus Nort.) with improved resistance to common root rot (Bipolaris sorokiniana (Sacc. in Sorok.) Shoem.) and seed shattering. It is adapted to the Brown and Dark Brown soil zones of Alberta and Saskatchewan and should be a suitable replacement for Canuck. It was licensed on 15 May 1985. Breeder seed of Lancer will be maintained by Agriculture Canada Research Station, Regina, Saskatchewan.Key words: Wheat (spring), cultivar decription
EARLIBRIGHT, AN EARLY PROCESSING TOMATO
Authors: METCALF JOHN G. , MOHR WILLARD P. , REYES ANDRES A.
Published: March 2010

Earlibright is an early, multiple hand-picked, dark crimson colored tomato suitable for the whole-pack and juice industry. It is resistant to blossom end rot, fruit cracking, and sun bleaching.Key words: Lycopersicon esculentum, blossom end rot, fruit cracking, sun bleaching, ethephon
FACTORS CONTROLLING THE RESPONSE OF FIELD CROPS TO VERY LOW DOSES OF GAMMA IRRADIATION OF THE SEED
Authors: SHEPPARD S. C. , EVENDEN W. G.
Published: March 2010

Stimulation of growth by very low doses of ionizing radiation, or hormesis, is a widely documented phenomenon. The biochemical mechanisms are unclear and the phenomenon is sporadic, controlled by factors as yet only poorly understood. Our study addressed factors reported to control the growth response of plants to seed irradiation. A growth chamber experiment compared the effects of four radiation sources on three crop species. Early emergence of flax (Linum usitatissimum) and early growth of wheat (Triticum aestivum) and barley (Hordeum vulgare) were increased by irradiation. These effects did not vary as a function of the photon-energy or dose-rate of the sources. Three field experiments were conducted where various cultivars and seed lots of wheat were irradiated at doses of 0.5–50 Gy using Cobalt-60. Early emergence was significantly accelerated in 7 of 18 seed lots. Grain yields were significantly increased in five cases for Neepawa or Glenlea cultivars, but were significantly decreased in nine other cases. The effects were not consistently related to measured seed lot characteristics, manipulation of the seed moisture content prior to irradiation, or the post-seeding environment as varied by delayed planting. In conclusion, there was some evidence of hormesis in emergence and early growth, but these effects did not persist to yield a benefit at harvest.Key words: Hormesis, stimulation, wheat, barley, flax, irradiation
A MUTANT GENOTYPE OF FLAX (Linum usitatissimum L.) CONTAINING VERY LOW LEVELS OF LINOLENIC ACID IN ITS SEED OIL
Authors: GREEN A. G.
Published: March 2010

Two flax (Linum usitatissimum L.) mutants having reduced linolenic acid content in their seed oil (M1589 = 19.1% linolenic; M1722 = 23.4% linolenic) were crossed to determine whether further reductions could be achieved by recombination of the mutant genes. Extensive transgressive segregation was evident in the F2 for both linolenic acid (1.2–36.6%) and linoleic acid (14.7–55.2%), which were strongly negatively correlated (r = −0.97). F2 plants homozygous for both the M1589 and M1722 mutations had very low levels of linolenic acid (<2%) and high levels of linoleic acid (>46%).Key words: Flax, linseed, Linum usitatissimum, linoleic acid, linolenic acid, seed oil
EFFECT OF PLANT DENSITY AND SOIL FERTILITY ON OILSEED SUNFLOWER GENOTYPES
Authors: GUBBELS G. H. , DEDIO W.
Published: March 2010

Field experiments were conducted in the 1979 to 1982 seasons to determine the response of sunflower (Helianthus annuus L.) genotypes with different growth habits to different plant densities at two levels of soil fertility in the Morden, Manitoba area. Treatments included hybrids and an open-pollinated cultivar, no fertilizer and 250 kg ha−1 of 27-14-0 and plant densities of 30 000, 45 000, 60 000 and 75 000 plants ha−1. Hybrids and open-pollinated cultivar responded similarly to the fertility and plant density levels. An increase in plant density did not affect yield, but slightly delayed flowering time, increased plant height, test weight and oil concentration and decreased achene weight. A plant density of about 45 000 plants ha−1 was required to ensure optimum yield.Key words: Sunflower, Helianthus annuus L., plant density, soil fertility
INFLUENCE OF DELAYED SEEDING ON YIELD, HECTOLITRE WEIGHT AND SEED SIZE OF STUBBLE-SEEDED WINTER WHEAT AND RYE GROWN IN SASKATCHEWAN
Authors: FOWLER D. B.
Published: March 2010

Winter wheat (Triticum aestivum L.) and rye (Secale cereale L.) were seeded into stubble the first week of September and October on four different years at a total of 11 sites in the central, eastern and northern part of the agricultural region of Saskatchewan. The average response to delayed seeding was a reduction in yield and hectolitre weight for both species. In contrast, date of seeding did not have a large influence on kernel size. A significant environmental effect was observed for all characters measured. Productivity of both wheat and rye was high when moisture conditions were adequate. Average yield of rye was higher and 1000-kernel and hectolitre weight lower than for wheat. Significant first and second order interactions demonstrated that the effects of seeding date, species and environment were not independent. These interactions were of sufficient magnitude to introduce a risk factor which should be taken into consideration when conclusions are drawn on the influence of seeding date on yield and other agronomic characters of stubble-seeded winter cereals.Key words: Triticum aestivum L., Secale cereale L., yield, hectolitre weight, kernel size, seeding date
GROWTHROOM EVALUATION OF SOYBEAN CULTIVARS FOR RESISTANCE TO Sclerotinia sclerotiorum
Authors: BOLAND G. J. , HALL R.
Published: March 2010

Forty-three soybean (Glycine max) cultivars were evaluated for resistance to Sclerotinia sclerotiorum in the growthroom by a modified limited-term-inoculation (LTI) method to determine whether any were more resistant than Evans. Cultivars were compared with Evans in small tests; those appearing to be more resistant were advanced for further testing. Averaged over three trials, Corsoy 79, Hodgson, Hawk and Pioneer 1677 were significantly (P = 0.05) more resistant than Evans. These same cultivars and Pioneer 0877, Maple Arrow, OAC 1981–3, Apache, Ozzie, and OAC 1981–4 were also more resistant than Evans in the last trial.Key words: Soybean, Sclerotinia sclerotiorum, disease resistance
EFFECT OF GENERATION AND LOCATION OF SEED PRODUCTION ON GROWTH HABIT AND ANTHRACNOSE RESISTANCE IN ARC ALFALFA
Authors: ELGIN Jr. J. H. , RINCKER C. M.
Published: March 2010

Thirty-one seedlots of Arc alfalfa (Medicago sativa L.), produced between 1971 and 1974 at Prosser, Wash.; Stanfield, Oreg.; and Shafter and Tehachapi, Calif., were evaluated for shifts in field growth habits (regrowth after cutting, winter injury, and date of flowering) and greenhouse anthracnose resistance. Seedlots represented one (Syn 2), two (Syn 3), and three (Syn 4) generations of increase beyond the original Syn 1 lot, grown under four diverse environments. Results indicated a tendency for shift in regrowth rate among the Syn 3 and Syn 4 generation seedlots produced at Shafter, Calif. No shift in regrowth rate was observed for the other locations and no significant trends away from the original lot were observed for winter injury, date of flowering or anthracnose resistance.Key words: Medicago sativa L., seed production, genetic shifts, anthracnose resistance, fall growth, regrowth
CAUSAL EFFECTS AMONG FORAGE YIELD AND QUALITY MEASURES OI SMOOTH BROMEGRASS
Authors: CASLER M. D.
Published: March 2010

Future improvement of forage quality in smooth bromegrass (Bromus inermis Leyss.) and other species will require a knowledge of the chemical and structural factors most limiting to digestibility and intake of dry matter by ruminants. The objective of this study was to estimate direct and indirect effects from path analysis of several forage constituents on in vitro dry matter digestibility (IVDMD) and forage yield of smooth bromegrass. Six hundred and fifteen spaced plants of B8HD smooth bromegrass were harvested at Arlington, Wis. in June 1982 to assess dry matter yield and forage constituents. Near-infrared reflectance (NIR) spectroscopy was used to estimate IVDMD, crude protein, neutral detergent fiber, acid detergent fiber, cellulose, acid detergent hemicellulose, acid detergent lignin, and ash based on a random calibration subset of 75 plants. Five independent variables comprised the path analysis model: crude protein, cellulose, hemicellulose, lignin, and ash. None of the variables directly or indirectly affected forage yield. Lignin and cellulose concentrations had the overwhelmingly largest direct effects on IVDMD, while hemicellulose was important only when expressed as a percentage of the cell wall. Crude protein was important, but only to a small extent, while ash had no effect on IVDMD. The largest indirect effects on IVDMD were generally indirect effects of each character through correlated changes in lignin and indirect effects of lignin through correlated changes in other characters. The large effects of lignin support previous work establishing lignin as the primary factor limiting IVDMD. The importance of cellulose compared to hemicellulose, a result contrary to many current theories on the role of cell walls in rumen digestion, emphasizes at least three factors contributing to differences between this study and previous studies: (1) species differences, (2) genetic vs. species and maturity effects, and (3) analytical procedures. Current evidence suggests a cell wall ideotype should have reduced cellulose and lignin with either reduced or unchanged hemicellulose concentration.Key words: Bromus inermis Leyss., cellulose, hemicellulose, in vitro dry matter digestibility, lignin, forage yield
EFFECTS OF NITROGEN APPLICATION ON YIELD AND QUALITY OF BROMEGRASS HAY IN CENTRAL ALBERTA
Authors: MALHI S. S. , McBEATH D. K. , BARON V. S.
Published: March 2010

Field experiments were conducted at four locations in central Alberta to determine the effect of N applications on dry matter yield and quality of bromegrass (Bromus inermis L.) hay. Ammonium nitrate was broadcast in early spring for 5 yr at rates of 0, 50, 100, 150, 200 and 300 kg N ha−1. In addition, fertilizer N was applied at 200 and 400 kg ha−1 only in the initial year to determine residual effects. Total dry matter yield (TDY) increased with increasing fertilizer N rates maximizing at 150 to 200, 100 to 150, 50 to 100 and 100 to 150 kg N ha−1 at Lacombe, Joffre, Botha, and Rocky Mountain House, respectively. Protein concentration and protein yield in bromegrass hay also increased with increasing N applications. Over the 4-yr period, TDY with initial N applications were generally lower than with the same total amount of N applied with annual rates. The residual effect of initial rates of N lasted only 2–3 yr following fertilizer application. With the exception of the Botha location, levels of NO3-N potentially toxic to livestock (>0.226%) were produced only in the first year. Potentially toxic NO3-N levels did not generally occur at those rates required to maximize TDY.Key words: Ammonium nitrate fertilizer, Bromus inermis, dry matter yield, nitrate-N concentration, protein concentration, protein yield
EFFECTS OF PHOSPHATE SPRAYS ON McINTOSH APPLE FRUIT AND LEAF COMPOSITION, FLESH FIRMNESS AND SUSCEPTIBILITY TO LOW-TEMPERATURE DISORDERS
Authors: WEBSTER D. H. , LIDSTER P. D.
Published: March 2010

Phosphate compounds (NH4H2PO4, KH2PO4 and CaH4(PO4)2 in 1982; NH4H2PO4 in 1983) applied to McIntosh apple trees as six foliar sprays at weekly intervals starting 4 wk after bloom, increased leaf and fruit P, decreased loss of firmness under some storage conditions and decreased incidence of low-temperature storage disorders. Phosphate sprays improved firmness retention of apples stored in either 5% CO2 plus 3% O2 or 0.7% CO2 plus 1% O2 in 1982 and maintained fruit firmness during a simulated shelf life at 20 °C for apples stored at 0 °C. Firmness retention at 20 °C of the 1983 crop was improved by monobasic ammonium phosphate regardless of storage temperature. Apple samples from unsprayed control trees had mean phosphorus concentrations of 85.4 and 94.4 ppm fresh weight in 1982 and 1983, respectively (whole fruit less seeds and stems).Key words: Apple, fruit phosphorus, low temperature breakdown, core flush
PEROXIDASE ZYMOGRAMS OF 16 APPLE ROOTSTOCKS
Authors: WELLER DAVID L. , COSTANTE JOSEPH F.
Published: March 2010

Shoot bark and root extracts of 16 different apple (Malus domestica Borkh.) root-stocks were analyzed for multiple electrophoretic forms of peroxidase (EC 1.11.1.7) using polyacrylamide gel electrophoresis (PAGE). Thirteen bands were seen in the peroxidase zymograms of shoot bark extracts and eight in the peroxidase zymograms of root extracts. The root peroxidase bands corresponded to ones in the shoot bark peroxidase zymograms. Two of the bands were common to all 16 rootstock patterns. The other 11 bands formed six patterns which were characterized by the presence of specific peroxidase bands. The 16 rootstocks were grouped according to banding characteristics.Key words: Apple, Malus domestica Borkh., apple rootstocks, PAGE-peroxidase zymograms
THE BIOLOGY OF CANADIAN WEEDS.: 75. Bromus tectorum L.
Authors: UPADHYAYA MAHESH K. , McILVRIDE DOUGLAS , TURKINGTON ROY
Published: March 2010

Bromus tectorum L. (downy brome), introduced to North America from Europe before 1861, has spread throughout most of the continent. It is present in all Canadian provinces except Newfoundland and is particularly abundant in southwestern Alberta and southern British Columbia. The ubiquitous nature of B. tectorum and its dual role as a serious weed and an important forage have resulted in extensive documentation on various aspects of its biology. Intensive research efforts have been expended in understanding its competitive success, and in implementing management and control practices. This paper reviews and summarizes literature on the biology of B. tectorum.Key words: Bromus tectorum, downy brome, cheatgrass, weed biology
THE BIOLOGY OF CANADIAN WEEDS.: 76. Vicia angustifolia L.,V. cracca L., V. sativa L., V. tetrasperma (L.) Schreb. and V. villosa Roth.
Authors: AARSSEN L. W. , HALL IVAN V. , JENSEN K. I. N.
Published: March 2010

This paper provides a summary of biological data on five weedy species of vetch (Vicia). All species are naturalized in Canada and are found in a wide range of habitats with their main centers of distribution in Eastern Canada and the south and coastal regions of British Columbia. Vicia cracca is the most common and serious problem and occurs nationwide. Vicia sativa is the most variable of the species; numerous subspecies, varieties, forms and hybrids are described. Tendrils allow vetches to attach to crop plants and form mat-like infestations. Vetch species are sensitive to a number of herbicides but there appears to be differential tolerance among species to chlorthal dimethyl, 2,4-DB and others. Vicia spp. are host to several economically important pathogens and parasites.Key words: Weed biology, vetches, Vicia spp., distribution
THE BIOLOGY OF CANADIAN WEEDS.: 77. Echinochloa crus-galli (L.) Beauv.
Authors: MAUN M. A. , BARRETT S. C. H.
Published: March 2010

Echinochloa crus-galli (L.) Beauv., barnyard grass (pied-de-coq), is an annual grass and a cosmopolitan weed with a range from 50°N to 40°S latitude. In Canada, it extends up to 53°N latitude in the prairies and is widely distributed along roadsides and in cultivated fields of all provinces. The success of this weed may be attributed to the production of large numbers of small, easily dispersed seeds per plant, possession of seed dormancy, rapid development and ability to flower under a wide range of photoperiods, and relative resistance of mature plants to herbicide sprays. In this review a summary of biological information on E. crus-galli is presented.Key words: Barnyard grass, weed biology, Echinochloa crus-galli
ETAT DE CROISSANCE DES CULTURES FOURRAGERES CARACTERISE PAR SIMULATION AEROPORTEE THEMATIC MAPPER DE LANDSAT-5
Authors: CARIGNAN M. , DUBOIS J. M. M. , BONN F. , PESANT A.
Published: March 2010

Two airborne surveys, simulating the spectral and spatial resolution of the Thematic Mapper sensor of Landsat-5 were made during the summer of 1982 (10 June and 18 Aug.). The Agriculture Canada Research Station at Lennoxville was surveyed and two common field crops in Quebec were studied. The digital image analysis revealed two parameters which influence the spectral signatures of the vegetation: the alfalfa plots presented spectral variations relative to cover structure which were associated with growth stage, and the corn plot analysis suggests a relation between the drainage conditions of the soil and growth characteristics.Key words: Remote sensing, airborne surveys, Thematic Mapper simulation, field crops, digital image analysis, spectral and multidate analysis