37 research outputs found
Identification of Species of Botryosphaeriaceae Causing Bot Gummosis in Citrus in California
Members of the Botryosphaeriaceae family are known to cause Bot gummosis on many woody plants worldwide. To identify pathogens associated with Bot gummosis on citrus in California, scion and rootstock samples were collected in 2010 and 2011 from five citrusgrowing counties in California. Symptoms observed on citrus included branch cankers, dieback, and gumming. Various fungal species were recovered from necrotic tissues of branch canker and rootstock samples. Species were identified morphologically and by phylogenetic comparison as âEurekaâ lemon, âValenciaâ, âWashington Navelâ, âFukumotoâ, grapefruit, âSatsumaâ, and âMeyerâ lemon. Species were identified morphologically and by phylogenetic comparison of the complete sequence of the internal transcribed spacer regions, β-tubulin gene, and elongation factor Îą-1 genes with those of other species in GenBank. A consensus-unrooted most parsimonious tree resulting from multigene phylogenetic analysis showed the existence of three major clades in the Botryosphaeriaceae family. In total, 74 isolates were identified belonging to the Botryosphaeriaceae family, with Neofusicoccum spp., Dothiorella spp., Diplodia spp., (teleomorph Botryosphaeria), Lasiodiplodia spp., and Neoscytalidium dimidiatum (teleomorphs unknown) accounting for 39, 25, 23, 10, and 3% of the total, respectively. On inoculated Eureka lemon shoots, lesion length was significantly different (P \u3c 0.05) among 14 isolates recovered from portions of cankered tissues of the original trees. Lesion lengths were significantly longer (P \u3c 0.05) for shoots inoculated with isolates of Neofusicoccum luteum and shorter for shoots inoculated with isolates of Dothiorella viticola (P \u3c 0.05) than those of other species. Identifying the distribution and occurrence of these fungal pathogens associated with Bot gummosis is useful for management applications during occasional outbreaks in California
Deux cas bĂŠninois dâentomophthoromycoses (basidiobolomycose et conidiobolomycose) diagnostiquĂŠs en 2010 au CHU dâAngers
National audienc
Conidiobolomycose rhinofaciale avec localisations cervicales, thoraciques et brachiales : Ă propos dâun cas nigĂŠrian
We report here the clinical case of a Nigerian adult patient who received medical care during October 2010, at the Center for Diagnosis and Treatment of Buruli ulcer in Pobè (Benin). He presented a massive facial tumor associated with several subcutaneous (cervical, thoracic and upper limbs) nodules, evolving since several years. Tissue samples collected at Pobè medical center were addressed to the mycology and histology laboratories of Angers University Hospital (France), according to the medical exchange agreement between the two institutions about the diagnosis and treatment of Buruli ulcer disease. Histological examination showed a Splendore-Hoeppli phenomenon, consisting of a granulomatous reaction made of eosinophilic polynuclear cells surrounding rare, large and irregular, non-septate hyphae. A filamentous fungus was isolated by cultivation of the clinical samples, which was identified as Conidiobolus coronatus. The patient was treated orally with daily doses of ketoconazole (400 mg per day). After 4 months of treatment, a marked regression of the facial lesion was obtained. A first constructive facial surgery was achieved, but the patient did not attend the second step. This case report allows us to remind the mycological diagnosis of this exotic mycosis, but also to emphasize the main difficulties encountered in medical management in the developing countries
Robust evidence for bats as reservoir hosts is lacking in most African virus studies : a review and call to optimize sampling and conserve bats
DATA ACCESSIBILITY : Data used in this study are available from the Dryad
Digital Repository: https://doi.org/10.5061/dryad.c866t1gcx [222].
Supplementary material is available online [223].Africa experiences frequent emerging disease outbreaks
among humans, with bats often proposed as zoonotic
pathogen hosts. We comprehensively reviewed virusâbat
findings from papers published between 1978 and 2020
to evaluate the evidence that African bats are reservoir
and/or bridging hosts for viruses that cause human disease.
We present data from 162 papers (of 1322) with
original findings on (1) numbers and species of bats
sampled across bat families and the continent, (2) how
bats were selected for study inclusion, (3) if bats were
terminally sampled, (4) what types of ecological data,
if any, were recorded and (5) which viruses were
detected and with what methodology. We propose a
scheme for evaluating presumed virusâhost relationships
by evidence type and quality, using the contrasting
available evidence for Orthoebolavirus versus Orthomarburgvirus
as an example. We review the wording
in abstracts and discussions of all 162 papers, identifying
key framing terms, how these refer to findings, and
how they might contribute to peopleâs beliefs about bats.
We discuss the impact of scientific research communication
on public perception and emphasize the need
for strategies that minimize humanâbat conflict and
support bat conservation. Finally, we make recommendations
for best practices that will improve virological
study metadata.Open access funding provided by the Max Planck Society. Bucknell University and, in part, by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health (NIH); the German Academic Exchange Service; the German Research Foundation the Institut Universitaire de France; the South African Research Chair Initiative of the Department of Science and Innovation and administered by the National Research Foundation (NRF) of South Africa; in part, by NSF and National Geographic and Rolex grants.https://royalsocietypublishing.org/journal/rsblam2024Medical VirologyNon
Identification of Species of Botryosphaeriaceae Causing Bot Gummosis in Citrus in California
Members of the Botryosphaeriaceae family are known to cause Bot gummosis on many woody plants worldwide. To identify pathogens associated with Bot gummosis on citrus in California, scion and rootstock samples were collected in 2010 and 2011 from five citrusgrowing counties in California. Symptoms observed on citrus included branch cankers, dieback, and gumming. Various fungal species were recovered from necrotic tissues of branch canker and rootstock samples. Species were identified morphologically and by phylogenetic comparison as âEurekaâ lemon, âValenciaâ, âWashington Navelâ, âFukumotoâ, grapefruit, âSatsumaâ, and âMeyerâ lemon. Species were identified morphologically and by phylogenetic comparison of the complete sequence of the internal transcribed spacer regions, β-tubulin gene, and elongation factor Îą-1 genes with those of other species in GenBank. A consensus-unrooted most parsimonious tree resulting from multigene phylogenetic analysis showed the existence of three major clades in the Botryosphaeriaceae family. In total, 74 isolates were identified belonging to the Botryosphaeriaceae family, with Neofusicoccum spp., Dothiorella spp., Diplodia spp., (teleomorph Botryosphaeria), Lasiodiplodia spp., and Neoscytalidium dimidiatum (teleomorphs unknown) accounting for 39, 25, 23, 10, and 3% of the total, respectively. On inoculated Eureka lemon shoots, lesion length was significantly different (P \u3c 0.05) among 14 isolates recovered from portions of cankered tissues of the original trees. Lesion lengths were significantly longer (P \u3c 0.05) for shoots inoculated with isolates of Neofusicoccum luteum and shorter for shoots inoculated with isolates of Dothiorella viticola (P \u3c 0.05) than those of other species. Identifying the distribution and occurrence of these fungal pathogens associated with Bot gummosis is useful for management applications during occasional outbreaks in California
Dynamics of soybean rust epidemics in sequential plantings of soybean cultivars in Nigeria
Soybean rust, caused by Phakopsora pachyrhizi, is an important foliar disease of soybean. Disease severity is dependent on several environmental factors, although the precise nature of most of these factors under field conditions is not known. To help understand the environmental factors that affect disease development, soybean rust epidemics were studied in Nigeria by sequentially planting an early-maturing, highly susceptible cultivar, TGx 1485-1D, and a late-maturing, moderately susceptible cultivar, TGx 1448-2E, at 30- to 45-day intervals from August 2004 to September 2006. Within each planting date, disease onset occurred earlier on TGx 1485-1D than on TGx 1448-2E, and rust onset was at least 20 days earlier on soybean planted between August and October than on soybean planted between November and April. The logistic model provided a better description of the temporal increase in rust severity than the Gompertz model. Based on the logistic model, the highest absolute rates of disease increase were observed on soybean planted in September 2006 and October 2004 for TGx 1485-1D and TGx 1448-2E, respectively. Disease severity as measured by the relative area under disease progress curve (RAUDPC) was significantly (P < 0.05) negatively correlated with evaporation (r = â0.73), solar radiation (r = â0.59), and temperature (r = â0.64) but positively correlated with urediniospore concentration (r = 0.58). Planting date and soybean cultivar significantly (P < 0.05) affected disease severity, with severity being higher on soybean crops planted during the wet season than those planted in the dry season. Within the wet season, planting in May and July resulted in a significantly (P < 0.05) lower RAUDPC than planting between August and October. Yields were significantly (P < 0.001) related to RAUDPC during the wet season, whereby an increase in RAUDPC resulted in a linear decrease in yield. This study suggests that selection of planting date could be a useful cultural practice for reducing soybean rust
Evaluation of soybean germplasm for resistance to soybean rust (Phakopsora pachyrhizi) in Nigeria
Soybean rust, caused by Phakopsora pachyrhizi, is one of the most important constraints to soybean production worldwide. The absence of high levels of host resistance to the pathogen has necessitated the continued search and identification of sources of resistance. In one set of experiments, 178 soybean breeding lines from the International Institute of Tropical Agriculture were rated for rust severity in the field in 2002 and 2003 at Ile-Ife, Yandev, and Ibadan, Nigeria. Thirty-six lines with disease severity â¤3 (based on a 0-to-5 scale) were selected for a second round of evaluation in 2004 at Ibadan. In the third round of evaluation under inoculated field conditions, 11 breeding lines with disease severity â¤2 were further evaluated for rust resistance at Ibadan in 2005 and 2006. The breeding lines TGx 1835-10E, TGx 1895-50F, and TGx 1903-3F consistently had the lowest level of disease severity across years and locations. In another set of experiments, 101 accessions from the United States Department of AgricultureâAgricultural Research Service and National Agriculture Research Organization (Uganda) were evaluated in the first round in 2005 under inoculated conditions in the screenhouse; 12 accessions with disease severity â¤20% leaf area infected were selected for evaluation in the second round in 2005 and 2006 under inoculated field conditions at Ibadan. Highly significant differences (P < 0.0001) in disease severity were observed among the 101 accessions during this first round of rust evaluation. Significant (P < 0.0001) differences in rust severity and sporulation also were observed among the 12 selected accessions. Accessions PI 594538A, PI 417089A, and UG-5 had significantly (P < 0.05) lower disease severity than all other selected accessions in both years of evaluation, with rust severities ranging from 0.1 to 2.4%. These results indicate that some of the breeding lines (TGx 1835-10E, TGx 1895-50F, and TGx 1903-3F) and accessions (PI 594538A, PI 417089A, and UG-5) would be useful sources of soybean rust resistance genes for incorporation into high-yielding and adapted cultivars