4 results on '"Heungens, Kurt"'
Search Results
2. Identification and early detection of Cryphonectria parasitica and Ceratocystis platani occurring on trees in Europe (CERACRY)
- Author
-
van Leeuwen, Gerard, Heungens, Kurt, Chandelier, Anne, Svobodová, Iveta, Tomankova, Katerina, Csertan-Halasz, Agnes, Destefanis, Maria, Pilotti, Massimo, Braganca, Helena, Perez-Sierra, Ana, Vettraino, Anna Maria, Parker, John, and Prospero, Simone
- Subjects
fungi ,Euphresco, plant health, Ceratocystis platani, Cryphonectria parasitica, mycology, survey, collections, diagnostics, TPS - Abstract
The overall goal of the project was to bring together scientists, practitioners and official national bodies (NPPOs) to share knowledge on two important quarantine diseases of trees in Europe: Ceratocystis platani and Cryphonectria parasitica. The threats posed by Ceratocystis platani are often underestimated and even in countries where the disease already occurs, not much measures are taken to limit the spread of this devastating disease. The project contributed to: Improve knowledge on the distribution of Cryphonectria parasitica in European countries. It was shown that C. parasitica is present in Belgium and United Kingdom, but not in Ireland. In the Netherlands, the fungus was found several times on imported Castanea stakes/fences in 2018, but not in nurseries or public green. Develop a collection of C. parasitica isolates. The isolates were used to determine the population structure of C. parasitica in Europe. Evidence was found that in countries where the pathogen was relatively recently described (e.g. UK), the pathogen was introduced several times but has not spread widely, possibly due to suboptimal climatic conditions. Organise a test performance study (TPS) for the real-time PCR test from Pilotti et al. (2012) for the detection of C. platani in wood. Specifically, EvaGreen, SYBR Green and Taqman tests were validated. Standard curves confirmed that the tests have high amplification efficiency. For analytical sensitivity, all laboratories detected 15 and 3 fg C. platani gDNA, thus reproducing the previously reported detection threshold of the method. Testing blind samples yielded a 100% scoring sensitivity, accuracy and specificity in all the experiments, with an exception in the SYBR Green test for which results from one laboratory were nonconforming for the criterion of accuracy.
- Published
- 2019
- Full Text
- View/download PDF
3. Oospores progenies from Phytophthora ramorum
- Author
-
Vercauteren Annelies, Boutet Xavier, Chandelier Anne, Laurent Fréderic, and Heungens Kurt
- Subjects
Phytophthora ,Spores ,Homothallism ,biology ,Reproduction ,Molecular Sequence Data ,fungi ,Context (language use) ,biology.organism_classification ,Magnoliopsida ,Infectious Diseases ,Phytophthora ramorum ,Botany ,Genetics ,Spore germination ,Oospore ,Heterothallic ,Ecology, Evolution, Behavior and Systematics ,Mycelium ,Microsatellite Repeats ,Plant Diseases - Abstract
Oospores of Phytophthora ramorum were produced from intraspecific pairings between a European A1 and European or American A2 strains. Their viability was evaluated through colouration with tetrazolium bromide. The distribution of oospores in the different classes of colouration was similar to that found in other Phytophthora species (homothallic and heterothallic): most of the oospores stained purple, which corresponds to spores in dormancy. In order to produce single-oospore cultures, a method was developed to separate oospores from mycelium and chlamydospores. Germination of oospores was observed in 110, 250, 350 and 500-d-old cultures at a low proportion. Microsatellite marker analyses on oospore progenies revealed that the oospores resulted from hybridisation. More than 50 oospore progenies were characterised in terms of mating type, aggressiveness on Rhododendron leaves, and growth rate on two different media. The results are discussed in the context of pest risk analysis.
- Published
- 2010
4. Global distribution of mating types shows limited opportunities for mating across populations of fungi causing boxwood blight disease.
- Author
-
Malapi-Wight, Martha, Veltri, Daniel, Gehesquière, Bjorn, Heungens, Kurt, Rivera, Yazmín, Salgado-Salazar, Catalina, and Crouch, Jo Anne
- Subjects
- *
BOXWOOD , *BLIGHT diseases (Botany) , *MYCOSES , *FUNGI , *SPECIES hybridization , *NATURAL landscaping - Abstract
• MAT1 loci with heterothallic organization identified from the two Calonectria that cause boxwood blight. • Calonectria pseudonaviculata isolates possess MAT1-2 mating type idiomorphs. • Calonectria henricotiae isolates possess MAT1-1 mating type idiomorphs. • Phylogenomic estimates place divergence of the boxwood blight pathogens at ∼2.1 Mya. • Minimal divergence between Che and Cps was observed in the genome region proximal to the MAT1 locus. Boxwood blight is a disease threat to natural and managed landscapes worldwide. To determine mating potential of the fungi responsible for the disease, Calonectria pseudonaviculata and C. henricotiae , we characterized their mating-type (MAT) loci. Genomes of C. henricotiae , C. pseudonaviculata and two other Calonectria species (C. leucothoes , C. naviculata) were sequenced and used to design PCR tests for mating-type from 268 isolates collected from four continents. All four Calonectria species have a MAT locus that is structurally consistent with the organization found in heterothallic ascomycetes, with just one idiomorph per individual isolate. Mating type was subdivided by species: all C. henricotiae isolates possessed the MAT1-1 idiomorph, whereas all C. pseudonaviculata isolates possessed the MAT1-2 idiomorph. To determine the potential for divergence at the MAT1 locus to present a barrier to interspecific hybridization, evolutionary analysis was conducted. Phylogenomic estimates showed that C. henricotiae and C. pseudonaviculata diverged approximately 2.1 Mya. However, syntenic comparisons, phylogenetic analyses, and estimates of nucleotide divergence across the MAT1 locus and proximal genes identified minimal divergence in this region of the genome. These results show that in North America and parts of Europe, where only C. pseudonaviculata resides, mating is constrained by the absence of MAT1-1. In regions of Europe where C. henricotiae and C. pseudonaviculata currently share the same host and geographic range, it remains to be determined whether or not these two recently diverged species are able to overcome species barriers to mate. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.