Diagnostic markers for Teratosphaeria destructans and closely related species

Teratosphaeria foliar pathogens cause leaf and shoot blight on Eucalyptus trees in many parts of the world. Among them, T. destructans is one of the most aggressive pathogens causing defoliation of young Eucalyptus trees in tropic regions. Identification of T. destructans to species level is currently not possible based solely on morphological characteristics or ITS sequence data. The aim of this study was to assess T. destructans microsatellites and a newly developed T. epicoccoides microsatellite as a diagnostic tool to differentiate among T. destructans and several closely related foliar pathogens. Based on the number of markers that amplified, the T. destructans microsatellites allowed for the differentiation of T. destructans, T. epicoccoides,T. eucalypti,T. nubilosa,T. pseudoeucalypti and T. viscidus. These microsatellites provide a rapid and cost-effective diagnostic tool that will enable the identification of a large number of isolates important in disease surveys and inoculation trials.Supplementary material: Table S1. Teratosphaeria isolates and their sequences used for phylogenetic analyses.Table S2. Microsatellite markers and panel designs for Teratosphaeria species.Table S3. BLASTn results of microsatellites in the Teratosphaeria genomes.The National Research Foundation, the SARChI Chair in Fungal Genomics, the UP Doctoral Research Bursary and the Tree Protection Co-operative program (TPCP).http://wileyonlinelibrary.com/journal/efp2021-10-27hj2021BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Genetic recombination in Teratosphaeria destructans causing a new disease outbreak in Malaysia

The Eucalyptus foliar pathogen Teratosphaeria destructans causes severe and widespread damage in South-East Asian and South African plantations. In 2016, leaf blight symptoms resembling those caused by T. destructans were observed in a plantation of a Eucalyptus grandis × E. urophylla hybrid in Sabah, Malaysia. The aims of this study were to confirm the identity of the causal agent as T. destructans and to investigate the genetic structure of isolates associated with this newly detected disease outbreak. Using sequence data of three gene regions, the identity of the pathogen was confirmed as T. destructans. The mating type and microsatellite genotypes of 41 isolates from this Malaysian population were identified and compared with those from previously characterized populations in South-East Asia and South Africa. The Malaysian population had the highest genotypic diversity of any T. destructans population thus far investigated. Both the mating types were found in the collection of isolates, and these were in approximately equal proportions. Although structures linked to a sexual state of the fungus have not been found, sexual reproduction is theoretically possible and could explain the high genetic diversity in the pathogen that must have been accidentally introduced into Malaysia. This is the first record of T. destructans in Sabah and, to the best of our knowledge, in also other parts of Borneo.The SARChI chair in Fungal Genomics; South African Agency for Science and Technology Advancement, Grant/Award Number: - NRF Centre of Excellence in Tree Health Biotechn; Tree Protection Co- operative program (TPCP); University of Pretoria (UP) Doctoral Research Bursary; National Research Foundation.http://www.wileyonlinelibrary.com/journal/efphj2022BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Genetic diversity of Teratosphaeria pseudoeucalypti in Eucalyptus plantations in Australia and Uruguay

Please read abstract in the article.http://link.springer.com/journal/133132022-06-16hj2022BiochemistryForestry and Agricultural Biotechnology Institute (FABI)GeneticsMicrobiology and Plant Patholog

Associations of airway inflammation and responsiveness markers in non asthmatic subjects at start of apprenticeship

<p>Abstract</p> <p>Background</p> <p>Bronchial Hyperresponsiveness (BHR) is considered a hallmark of asthma. Other methods are helpful in epidemiological respiratory health studies including Fractional Exhaled Nitric Oxide (FENO) and Eosinophils Percentage (EP) in nasal lavage fluid measuring markers for airway inflammation along with the Forced Oscillatory Technique measuring Airway resistance (AR). Can their outcomes discriminate profiles of respiratory health in healthy subjects starting apprenticeship in occupations with a risk of asthma?</p> <p>Methods</p> <p>Rhinoconjunctivitis, asthma-like symptoms, FEV1 and AR post-Methacholine Bronchial Challenge (MBC) test results, FENO measurements and EP were all investigated in apprentice bakers, pastry-makers and hairdressers not suffering from asthma. Multiple Correspondence Analysis (MCA) was simultaneously conducted in relation to these groups and this generated a synthetic partition (EI). Associations between groups of subjects based on BHR and EI respectively, as well as risk factors, symptoms and investigations were also assessed.</p> <p>Results</p> <p>Among the 441 apprentice subjects, 45 (10%) declared rhinoconjunctivitis-like symptoms, 18 (4%) declared asthma-like symptoms and 26 (6%) suffered from BHR. The mean increase in AR post-MBC test was 21% (sd = 20.8%). The median of FENO values was 12.6 ppb (2.6-132 range). Twenty-six subjects (6.7%) had EP exceeding 14%. BHR was associated with atopy (p < 0.01) and highest FENO values (p = 0.09). EI identified 39 subjects with eosinophilic inflammation (highest values of FENO and eosinophils), which was associated with BHR and atopy.</p> <p>Conclusions</p> <p>Are any of the identified markers predictive of increased inflammatory responsiveness or of development of symptoms caused by occupational exposures? Analysis of population follow-up will attempt to answer this question.</p