Detection of Chalara fraxinea from tissue of Fraxinus excelsior using species‐specific ITS primers

Abstract

Chalara fraxinea (teleomorph: Hymenoscyphus albidus) is known as a serious pathogen of Fraxinus excelsior, causing massive dieback of trees in Europe. The fungus is able to cause latent infections, and has been previously detected as an endophyte in asymptomatic tissues. Chalara fraxinea is a slow grower in culture, and is thus likely to be overgrown by faster growing fungi whenever pure culture isolations are being attempted. This study reports species-specific ITS primers allowing fast and reliable detection of the pathogen directly from infected tissues of F. excelsior.

Patterns and severity of crown dieback in young even-aged stands of european ash (Fraxinus excelsior L.) in relation to stand density, bud flushing phenotype, and season

“…In all stands ash dieback has been observed at least since 2006, and H. pseudoalbidus was consistently isolated from symptomatic shoots (Johansson et al 2009b). A total of 3180 trees were evaluated for crown dieback: 1945 trees in seven unthinned plots of 1700-5500 trees/ha, 777 trees in six plots with a residual stem density of 1500 trees/ha, 397 trees in six plots of 500 trees/ha, and 61 trees in two plots Evaluation of tree flushing and dieback.…”

Presence of natural genetic resistance in Fraxinus excelsior (Oleraceae) to Chalara fraxinea (Ascomycota): an emerging infectious disease

“…The fungus has been isolated and confirmed by molecular markers from symptomatic trees in affected stands throughout Europe (Kowalski, 2006;Bakys et al, 2009a;Chandelier et al, 2009;Ioos et al, 2009;Johansson et al, 2010). The epidemiology of the fungus was further elucidated when the teleomorph was identified.…”

The susceptibility of Asian, European and North American Fraxinus species to the ash dieback pathogen Hymenoscyphus fraxineus reflects their phylogenetic history

“…DNA was extracted from at least one apothecium per ash species with a DNeasy Plant mini Kit (Qiagen, Hilden Germany) following the manufacturer's protocol except for excluding the shredder column. PCRs were performed as described in an earlier study (Johansson et al 2010) and run on a Biorad thermo cycler (model c1000). PCR products from H. fraxineus were identified following McKinney et al (2012a).…”