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PURPOSE: We determined over-the-counter magnifier usage rates by patients who newly presented for vision rehabilitation services, and sought to elucidate whether patients' ratings of over-the-counter magnifiers were associated with vision rehabilitation management strategies. METHODS: Retrospective records reviews of 274 new vision rehabilitation patients seen between 2021-2023 were completed by three optometric providers at an ophthalmic academic center, college of optometry, and private practice. RESULTS: Over half (58%) of patients tried an over-the-counter magnifier. Older age was significantly associated with trying over-the-counter magnifiers (OR:1.04; p < 0.001). Patients who tried an over-the-counter magnifier had significantly greater odds of the provider recommending and/or dispensing a prescribed hand-held optical illuminated magnifier (P< =0.04) or recommending a CCTV electronic magnifier (p = 0.049). The majority indicated over-the-counter magnifiers were somewhat (46%) or not helpful (38%). There was a significantly greater odds of rating the over-the-counter magnifier as not helpful when the provider subsequently recommended a CCTV (OR:4.8; p = 0.01) or higher spectacle-based near add power (OR: 2.0; p = 0.02). CONCLUSIONS: Since most new patients were unsatisfied with over-the-counter magnifiers, it is encouraging that previous over-the-counter magnifier use often led to upgrades with hand-held optical illuminated magnifiers prescribed by vision rehabilitation providers, or patients were transitioned to CCTV electronic magnifiers or spectacle-based high add powers for near reading. These findings support that older adults who have previously experienced that over-the-counter magnifiers were either helpful or unhelpful are ideal candidates to receive vision rehabilitation by optometric providers who can transition them to a prescribed magnification device to better support their visual functioning needs for near reading.
Over-the-counter magnifiers were deemed helpful by only a small proportion of visually-impaired patients who were newly seeking vision rehabilitation services; but there other are viable options for them, since optometric vision rehabilitation providers prescribed alternative magnification devices, such as spectacle-based high near add powers or electronic visual aids for patients.Patients who have previously tried an over-the-counter magnifier were often recommended and received a different magnification device from vision rehabilitation providers who should be encouraged to evaluate other aids in-office to determine if they are more acceptable and/or better suited to meet patients' needs.For patients and their families who have not yet pursued vision rehabilitation, our findings indicate that they should not give up on magnifiers and remain open to the possibility of using other types of magnification that could be helpful, such as a different optical magnifier, prescription for strong near reading glasses, electronic video magnification, or visual assistive apps for smartphones or tablets.
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Purpose: An evidence basis is lacking but needed to compare reading ability outcomes after magnification device training remotely via telerehabilitation versus in office. Methods: A multicenter randomized controlled trial at academic centers and vision rehabilitation private practices randomized 61 visually impaired adults to telerehabilitation or in-office training 1 to 4 months after dispensing new portable electronic, hand-held, or stand optical magnifiers. Telerehabilitation included loaner equipment for Zoom videoconferencing with remote control access software. Using a multilevel regression model, changes in Activity Inventory responses using Rasch analysis estimated reading ability in dimensionless log odds units (logits) (0.14-logit change corresponds with ability change expected from a one-line change in visual acuity). Results: Across 47 participants who completed the trial, reading ability with new magnifiers improved significantly by 0.61 logits on average (95% confidence interval [CI], 0.36-0.86; P < 0.001) from baseline to 1 month, and by an additional 0.44 logits on average (95% CI, 0.19-0.69; P < 0.001) from 1 to 4months (i.e., after magnifier training), with very similar significant findings for both telerehabilitation (n = 29; mean improvement = 0.44 logits; 95% CI, 0.08-0.80; P = 0.018) and in-office training (n = 18; mean improvement = 0.43 logits; 95% CI, 0.15-0.71; P = .003), and no significant difference between randomized groups across both follow-ups (95% CI, -0.43 to 0.61; P = .73). Vision, demographics, and health factors were nonsignificantly related to reading ability changes from 1 to 4 months. Conclusions: Reading ability improved after the provision of newly dispensed magnifiers, with further improvements following additional magnifier training via either telerehabilitation or in-office usual care. Translational Relevance: These findings provide support for the use of telerehabilitation to enhance reading ability with newly prescribed magnifiers as an alternative modality of care delivery.
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Telerreabilitação , Baixa Visão , Adulto , Humanos , Baixa Visão/reabilitação , Acuidade Visual , Atividades Cotidianas , LeituraRESUMO
SIGNIFICANCE: Vision rehabilitation providers tend to recommend handheld, illuminated optical magnifiers for short-duration spot reading tasks, but this study indicates that they are also a viable option to improve sustained, continuous text reading (e.g., books or magazines), especially for visually impaired adults who read slowly with only spectacle-based near correction. PURPOSE: The utility of handheld optical magnifiers for sustained silent reading tasks involving normal-sized continuous text could be a valuable indication that is not recognized by vision rehabilitation providers and patients. METHODS: Handheld, illuminated optical magnifiers were dispensed to 29 visually impaired adults who completed the sustained silent reading test by phone at baseline without the new magnifier and 1 month after using the magnifier. Reading speed in words per minute (wpm) was calculated from the time to read each page and then averaged across up to 10 pages or determined for the fastest read page (maximum). RESULTS: From baseline without the magnifier to 1 month with the magnifier, there was a significant improvement in mean reading speed by 14 wpm (95% confidence interval [CI], 2.6 to 24; P = .02) and for maximum reading speed by 18 wpm (95% CI, 5.4 to 30; P = .005) on average across participants. Participants who had slower baseline reading speeds without the magnifier demonstrated significantly greater improvements in mean and maximum reading speeds on average with the magnifier (95% CI, 8 to 32 [ P = .003]; 95% CI, 4 to 36 [ P = .02]). A significantly greater number of pages were read with the new magnifier than without it (Wilcoxon z = -2.5; P = .01). A significantly greater number of pages were read with the magnifier by participants who read fewer pages at baseline (95% CI, 0.57 to 5.6; P = .02) or had greater improvements in mean reading speed (95% CI, 0.57 to 5.6; P = .007). CONCLUSIONS: Many visually impaired adults read more quickly and/or read a greater number of pages after using a new magnifier for a month than compared to without it. The largest gains occurred among those with more difficulty at baseline, indicating the potential to improve reading rates with magnifiers for those with greater deficits.
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Auxiliares Sensoriais , Baixa Visão , Humanos , Adulto , Acuidade Visual , Leitura , Óculos , Baixa Visão/reabilitaçãoRESUMO
SIGNIFICANCE: This pilot study provides some insight about the potential benefits of telerehabilitation training to improve the reading ability of adults with low vision using magnifiers, to spur future work with larger groups. Telerehabilitation services can be implemented clinically to facilitate access to follow-up care for low vision. PURPOSE: A recent Cochrane systematic review revealed that there are no published visual function outcomes for telerehabilitation with handheld magnification devices for low vision; thus, this study aimed to provide evidence for its preliminary efficacy. METHODS: One to 4 months after receiving a new magnification device (i.e., handheld or stand optical magnifier or portable electronic magnifier), 14 adult low vision patients (with any visual acuity level or ocular diagnosis) received two training sessions at home via telerehabilitation with their vision rehabilitation provider located remotely in-office. Telerehabilitation included a loaner smartphone for Zoom videoconferencing with remote control access software. The Minnesota Low-Vision Reading Test was administered during each of the telerehabilitation sessions to assess near reading (acuity and speed) with the new magnifier. RESULTS: Mean reading acuity with the magnifier was 0.17 logMAR across subjects before training at telerehabilitation session 1, which significantly improved to 0.09 on average a few weeks later at telerehabilitation session 2 (95%confidence interval, -0.001 to -0.16; P = .047). Logarithm reading speed with the magnifier for the reading acuity level at session 1 improved significantly by 0.18 log words per minute on average for the same text size at session 2 (95% confidence interval, 0.06 to 0.29; P = .002). With the magnifier at session 2, 71% of participants gained at least 0.1 log unit in reading acuity, and half improved by >0.01 in log reading speed; all participants with increased reading speed also improved in reading acuity ( P = .02). CONCLUSIONS: These preliminary data support that telerehabilitation can enhance reading ability and efficiency with newly prescribed magnifiers as an alternative option to in-office vision rehabilitation.
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Telerreabilitação , Baixa Visão , Adulto , Óculos , Humanos , Projetos Piloto , LeituraRESUMO
Purpose: We examined different methods to reduce the burden of accessing technology for videoconferencing during telerehabilitation for magnification devices for the visually impaired. Methods: During telerehabilitation studies over the past 5 years, vision rehabilitation providers assessed and gave training to visually impaired participants with newly dispensed magnification devices at home who connected to Zoom videoconferencing via loaner tablets or smartphones with assistance from (phase 1; n = 10) investigators by phone, (phase 2; n = 11) local Lions Club volunteers in participants' homes, or (phase 3; n = 24) remote access control software in a randomized controlled trial with 13 usual care controls who received in-office training. All participants completed the same post-telerehabilitation phone survey. Results: A significantly greater proportion of phase 3 subjects indicated they strongly or mostly agreed that the technology did not interfere with the session (96%) compared to phase 1 (60%; 95% confidence interval [CI], 1.2-12.5; P = 0.03) or phase 2 (55%; 95% CI, 1.8-188; P = 0.01). The majority indicated telerehabilitation was as accurate as in person (68%), they were comfortable with telerehabilitation (91%) and interested in a future session (83%), and their magnifier use improved (79%), with no significant differences in these responses between phases (all P > 0.10), including comparisons of participants randomized to telerehabilitation or in-office training in phase 3 who reported similar overall satisfaction levels (P = 0.84). Conclusions: Participants across all phases reported high levels of acceptance for telerehabilitation, with least interference from technology using remote access control in phase 3. Translational Relevance: With accommodations for accessibility to videoconferencing technology, telerehabilitation for magnification devices can be a feasible, acceptable, and valuable option in countries with resources to support the technology.
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Telerreabilitação , Baixa Visão , Olho Artificial , Óculos , Humanos , Telerreabilitação/métodos , Comunicação por Videoconferência , Baixa Visão/reabilitaçãoRESUMO
Management of dollar spot (incited by Sclerotinia homoeocarpa) on golf course fairways is increasingly challenging. The objectives of this study were to determine the influence of mowing frequency and plant growth regulators (PGRs) on dollar spot severity and on the residual efficacy of fungicides for control of dollar spot. Two 4-month-long studies were conducted on 'Putter' creeping bentgrass (Agrostis stolonifera) maintained as a fairway at the University of Connecticut. Treatments were arranged in a three-by-three-by-five factorial that assessed the influence of mowing frequency (2, 4, or 6 days week-1) and PGRs (paclobutrazol, trinexapac-ethyl, or none) on dollar spot control by five fungicide treatments (boscalid, chlorothalonil, iprodione, propiconazole, or none). Turf was mowed in the afternoon hours to minimize the confounding effect of mowing frequency on leaf wetness duration. Treatments were initiated in the late spring of 2007 and 2008, and each fungicide treatment was reapplied only when dollar spot exceeded a threshold of five infection centers plot-1. In the absence of fungicides, dollar spot severity was reduced by 63 to 90% in plots treated with paclobutrazol and by 13 to 55% in plots treated with trinexapac-ethyl. Dollar spot severity was 23 to 50% lower in plots mown 2 days week-1 compared with those mown 6 days week-1. In cases where a significant interaction was observed between mowing frequency and PGRs, dollar spot was reduced on most rating dates in plots treated with trinexapacethyl that were mown 2 days week-1 compared with those mown 6 days week-1. Survival analysis of days until threshold was met revealed that duration of control of fungicides in plots receiving paclobutrazol were 28 to 84% longer compared with plots not receiving PGR. Duration of control by fungicides was generally similar between plots treated with trinexapac-ethyl and no PGR. In general, mowing frequency did not influence duration of control. Results from this study indicate that paclobutrazol could be used to increase the treatment interval of fungicides and that mowing frequency in the absence of dew is likely to have little influence on fungicide residual efficacy. When used without fungicides, PGRs and less frequent mowing may reduce dollar spot in situations where fungicide use is limited.
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Dollar spot (Sclerotinia homoeocarpa) is a severe disease problem on creeping bentgrass (Agrostis stolonifera) fairways. The objective of this study was to evaluate the effects of dew removal and mowing frequency on fungicide performance for dollar spot control. In 2009 and 2010, an experiment involving daily dew removal or no dew removal, mowing frequency (2, 4, and 6 days week-1), and fungicides (chlorothalonil, propiconazole, and iprodione) was conducted on creeping bentgrass maintained as a fairway. Daily dew removal resulted in fewer dollar spot infection centers (IC) compared with not removing dew during late summer 2009 and 2010 for all mowing-frequency and fungicide treatments. As mowing frequency increased from 2 to 6 days week-1, dollar spot IC decreased when averaged across all fungicide treatments. For all fungicides, daily dew removal increased the number of days needed to reach a 15-IC plot-1 point of reference when compared with fungicide treatments in which dew was not removed. The number of days required to reach 15 IC varied with fungicide, mowing frequency, and year the test was conducted. Results demonstrate that dollar spot control with fungicides can be extended when daily dew removal is employed and, in some cases, when mowing frequency is increased on dew-covered turf. Benefits of dew-removal practices on dollar spot and fungicide performance can vary with weather conditions, fungicide, threshold level, and possibly other factors.
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Chemical management of dollar spot in turf may lead to the development of Sclerotinia homoeocarpa populations with reduced fungicide sensitivity. The objective of this study was to determine the scope of S. homoeocarpa insensitivity to fungicides commonly used to control dollar spot on golf courses in the northeastern United States. A total of 965 and 387 isolates of S. homoeocarpa from intensively or individually sampled sites, respectively, were evaluated for in vitro sensitivity to iprodione, propiconazole, and thiophanate-methyl. Mean baseline sensitivities to iprodione and propiconazole were 0.2763 and 0.0016 µg a.i. ml-1, respectively, and all baseline isolates were sensitive to thiophanate-methyl at 1,000 µg a.i. ml-1. When compared with the baseline population, 14 and 18 of 20 total populations were less sensitive to iprodione and propiconazole, respectively. Individually sampled isolates obtained from fairways, putting greens, or tees were less sensitive to iprodione and propiconazole when compared with the baseline. For thiophanate-methyl, five populations were sensitive, six were resistant, and the remaining nine populations contained various proportions (2 to 92%) of resistant isolates. Individually sampled isolates obtained from fairways and putting greens were evaluated for associations in sensitivity among the three fungicides. A weak but positive correlation in sensitivity to iprodione and propiconazole was observed for isolates resistant to thiophanate-methyl but correlations for sensitive isolates were not significant. Furthermore, isolates with highly reduced sensitivity to iprodione clustered in a narrow range of propiconazole sensitivity. These data suggest the possible existence of resistance mechanisms common to diverse fungicide classes. Overall, results indicate that insensitivity of S. homoeocarpa to iprodione, propiconazole, and thiophanate-methyl exists in varying degrees on golf courses in the northeastern United States.
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Waitea circinata var. circinata is the causal agent of brown ring patch, an emergent disease of turfgrass in the United States. Forty-two isolates from annual bluegrass were obtained from California, Connecticut, Idaho, Illinois, Massachusetts, New York, Ohio, Oregon, and Rhode Island. Almost all isolates produced white to orange sclerotia (bulbils), 2 to 5 mm in size, that turned dark brown after 21 days on »-strength potato dextrose agar. The ribosomal DNA internal transcribed spacer regions and 5.8S region (ITS) were analyzed by restriction fragment length polymorphism (RFLP) analysis using MspI and sequencing to attempt identification of the isolates. Some isolates were heterozygous at the MspI restriction site, results not found in previous reports using the RFLP technique for identification. Four additional nucleotide positions were found to be variable within ITS based on sequence analysis, including two indels and two additional heterozygous positions. A total of 17 ITS haplotypes were found, and there was no obvious relationship between ITS haplotype and the geographic distribution of the isolates. Results of this work indicate that W. circinata var. circinata is present in multiple states and provide an initial understanding of the diversity of the pathogen in the United States.
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Dead spot of creeping bentgrass is incited by Ophiosphaerella agrostis. The objectives of this 3-year field study were to: (i) elucidate environmental conditions associated with the expression of dead spot symptoms, (ii) develop a model to assist in predicting the appearance of dead spot symptoms and epidemics in creeping bentgrass, and (iii) elucidate the association between ascospore release and the appearance of new dead spot symptoms. Environmental parameters measured included relative humidity (RH), air (AT) and soil (ST) temperatures, solar irradiance (SOL), precipitation and irrigation (RAIN), and leaf wetness duration (LWD). Dead spot symptoms generally did not occur at temperatures (air or soil) below 15°C. Two descriptive models were developed that predicted the appearance of dead spot symptoms with an accuracy of 74 to 80%. Between 1 May and 31 October 2000 to 2002, the appearance of new dead spot infection centers was most accurately predicted (80%) by the single parameter of STMean ≥ 20°C. In years with severe levels of dead spot, the occurrence of major infection events was predicted on 37 of 40 days (93%). A combination of elevated air (ATMax ≥ 27°C) and soil (STMean ≥ 18°C) temperatures, low relative humidity (RHMean ≤ 80%), shortened periods of leaf wetness (LWD ≤ 14 h), and high levels of solar radiation (SOLMean ≥ 230 W m-2) were associated with the development of major dead spot epidemics. Ascospore discharge and the appearance of new infection centers occurred in a cyclic pattern that peaked about every 12 days. New infection centers appeared 3 to 10 days after the release of a large number of ascospores.
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The diagnosis and treatment (including low vision rehabilitation) of permanent vision impairment due to ocular disease and trauma are gaining increased emphasis around the world. In the United States, this emphasis is due to both changing demographics and emerging policies issued by the US Centers for Medicare and Medicaid Services (CMS). In this de facto report, we trace the evolution of low vision rehabilitation service in Michigan, highlighting the role of public appropriations initiated in the mid 1960s and continuing today. An array of state, private, nonprofit, and clinical services for vision rehabilitation in Michigan are described in the context of the historical roots, current roles, and future trends related to emerging policies and systems of care.
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Atenção à Saúde/organização & administração , Baixa Visão/reabilitação , Pessoas com Deficiência Visual/reabilitação , Política de Saúde , Pesquisa sobre Serviços de Saúde , Humanos , Michigan , Modelos OrganizacionaisRESUMO
ABSTRACT Dead spot (Ophiosphaerella agrostis) is a damaging disease of young =6 years old) creeping bentgrass (Agrostis stolonifera) golf greens. The objectives of this 3-year field study were to determine the peak periods of dead spot activity based on increasing patch diameter and pseudothecia development, and to determine where O. agrostis overwinters. Patch diameter generally increased at a linear rate between mid-June and early August. Increases in pseudothecia production closely followed increasing patch diameter. Pseudothecia could be found within necrotic tissue as early as the first day of symptom expression and as many as 478 pseudothecia were found in a single patch. Periods of rapid dead spot development coincided with air and soil temperatures ranging from 22 to 26 degrees C. Increases in patch diameter and pseudothecia development were negligible after late August. Dead spot severity was highest in the year following green construction or fumigation, but then rapidly declined in severity in subsequent years. O. agrostis was capable of overwintering as pseudothecia or as hyphae within or on bentgrass leaf sheaths, crowns, roots, and especially the nodes of stolons.
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Dead spot (Ophiosphaerella agrostis) is a relatively new disease of young creeping bentgrass and hybrid bermudagrass putting greens in the United States. Little is known about the biology or genetic diversity of the pathogen. O. agrostis is unusual in that it produces prodigious numbers of pseudothecia in the field throughout the summer months and has no known asexual state. A total of 77 O. agrostis isolates were collected from 21 different bentgrass putting greens and one hybrid bermudagrass green in 11 states. DNA fingerprint analysis revealed that 78 out of 97 markers were polymorphic (80.4%), providing 57 unique profiles. Genetic variation of O. agrostis was diverse, and isolates separated into three distinct clades with ≥69% similarity. Analysis of molecular variance indicated that the geographic origins of the isolates and the ability to produce pseudothecia were the best indicators for genetic similarity among O. agrostis isolates. Colony color varied among the isolates, but generally was similar for isolates residing within two clades (B and C). Colony color of isolates within clade A appeared to be a mixture of the colony colors exhibited by clades B and C. Isolates examined within each clade generally had varying levels of pseudothecia production and varying colony colors when grown on PDA. Although O. agrostis is a homothallic species, it is unclear if outcrossing among strains occurs.
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BACKGROUND: Patients with multi-handicaps present clinical challenges and are underserved. Central nervous system dysfunction and ocular disorders with this population are prevalent and well-documented. However, vision care outcomes data are limited and specific visual function recommendations to caregivers are rarely cited. METHODS: The charts of 110 multiply handicapped adults residing in 22 group homes in Wayne County. Michigan were retrospectively studied to identify ocular profiles and predictors of visual function. RESULTS: Sixty-five percent of the subjects were male and 80% were ages 26 to 55 years. There was no expressive language in 41%, and 37% were non-ambulatory. The median visual impairment level was moderate in both eyes (based on WHO). Significant associations between visual impairment level and subpopulations (such as seizure disorder, mental retardation without specific etiology, cerebral palsy, and Down syndrome) were identified. Successful spectacle wear statistically increased with higher refractive errors. Associations between cataract, nystagmus, and strabismus with particular subpopulations were significant (all P values < 0.0182). CONCLUSIONS: Clinicians who evaluate patients with multi-handicaps have few known predictors of treatment success. This study indicates that useful predictors of visual function can be made from refractive error, systemic conditions, and ocular diagnoses. No significant relationship was found with cognitive level and either vision impairment or spectacle use. The authors attribute successful implementation of recommendations to communication with group home caregivers.
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Atenção à Saúde/estatística & dados numéricos , Pessoas com Deficiência/estatística & dados numéricos , Lares para Grupos/estatística & dados numéricos , Transtornos da Visão/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Michigan/epidemiologia , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Prevalência , Transtornos da Visão/diagnóstico , Acuidade VisualRESUMO
Dead spot is a relatively new disease of creeping bentgrass and hybrid bermudagrass that is incited by Ophiosphaerella agrostis. Initial symptoms are difficult to diagnose and clinicians generally rely on the presence of pseudothecia within infected tissue or isolation of O. agrostis on an artificial medium. The main goal of this study was to develop a polymerase chain reaction-based technique capable of quickly identifying O. agrostis within infected creeping bentgrass tissues. Oligonucleotide primers specific for O. agrostis were developed based on the internal transcribed spacer (ITS) rDNA regions (ITS1 and ITS2) of three previously sequenced isolates of O. agrostis. The 22-bp primers amplified a 445- or 446-bp region of 80 O. agrostis isolates collected from creeping bentgrass and bermudagrass in 11 states. Primers did not amplify DNA from other common turfgrass pathogens, including three closely related species of Ophiosphaerella. Selective amplification of O. agrostis was successful from field-infected creeping bent-grass samples and primers did not amplify the DNA of noninfected, field-grown creeping bent-grass or hybrid bermudagrass plants. Amplification of purified O. agrostis DNA was successful at quantities between 50 ng and 5 pg. The entire process, including DNA isolation, amplification, and amplicon visualization, may be completed within 4 h. These results indicate the specificity of these primers for assisting in the accurate and timely identification of O. agrostis and the diagnosis of dead spot in both bentgrass and bermudagrass hosts.
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ABSTRACT Ophiosphaerella agrostis, the causal agent of dead spot of creeping bentgrass (Agrostis stolonifera), can produce prodigious numbers of pseudothecia and ascospores throughout the summer. The environmental conditions and seasonal timings associated with O. agrostis ascospore release are unknown. The objectives of this research were to (i) determine the influence of light and relative humidity on ascospore release in a controlled environment, (ii) document the seasonal and daily discharge patterns of ascospores in the field, and (iii) elucidate environmental conditions that promote ascospore release under field conditions. In a growth chamber, a sharp decrease (100 to approximately 50%; 25 degrees C) in relative humidity resulted in a rapid (1- to 3-h) discharge of ascospores, regardless of whether pseudothecia were incubated in constant light or dark. In the field, daily ascospore release increased between 1900 and 2300 h and again between 0700 and 1000 h local time. The release of ascospores occurred primarily during the early morning hours when relative humidity was decreasing and the canopy began to dry, or during evening hours when relative humidity was low and dew began to form. Few ascospores were released between 1100 and 1800 h when the bentgrass canopy was dry. The release of ascospores also was triggered by precipitation. Of the ascospores collected during precipitation events, 87% occurred within 10 h of the beginning of each event.
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Bentgrass dead spot (BDS) is a disease of creeping bentgrass incited by Ophiosphaerella agrostis. This project was designed to determine the susceptibility of field-grown bentgrass cultivars to BDS and to gather information regarding the geographic distribution and field conditions favoring the disease. In a field cultivar evaluation trial, all major Agrostis spp. used on golf courses, including colonial, creeping, and velvet bentgrasses, were shown to be susceptible to an isolate of O. agrostis. Velvet bentgrass cvs. SR7200 and Bavaria were among the most and least susceptible cultivars, respectively. Among creeping bentgrass cultivars, L-93 generally was the most susceptible and Pennlinks, Penncross, and Crenshaw were among the least susceptible. Although recovery of BDS patches in the autumn was slow, Bardot colonial bentgrass and Crenshaw, Imperial, L-93, and Penn G-6 creeping bentgrasses showed the most rapid recovery prior to winter. Variation in the virulence of isolates and the potential for races of the pathogen, however, may affect cultivar susceptibility. The disease was most commonly found on 1- to 4-year-old golf greens and disease severity declined 1 to 3 years after it first appeared. BDS only was found on sand-based greens, collars, and tees and has not been observed in bentgrass grown on native soil. Between 1998 and 2001, O. agrostis was isolated from diseased leaves, roots, crowns, and stolons of creeping bentgrass and hybrid bermudagrass turf samples received from 13 states. The disease was most severe in sunny and exposed locations, especially on ridges, mounds, and slopes. In the mid-Atlantic region, BDS appeared as early as May and remained active as late as December. The disease was most active in July and August, and usually became inactive with the advent of frost in October.