Correspondence between symptom development of Colletotrichum graminicola and fungal biomass, quantified by a newly developed qPCR assay, depends on the maize variety.

Background: Penetration attempts of the hemibiotroph Colletotrichum graminicola may activate PAMP-triggered immunity (PTI) on different cultivars of Zea mays to different extent. However, in most events, this does not prevent the establishment of a compatible pathogenic interaction. In this study, we investigate the extent to which the host variety influences PTI.

New gene models and alternative splicing in the maize pathogen Colletotrichum graminicola revealed by RNA-Seq analysis.

Background: An annotated genomic sequence of the corn anthracnose fungus Colletotrichum graminicola has been published previously, but correct identification of gene models by means of automated gene annotation remains a challenge. RNA-Seq offers the potential for substantially improved gene annotations and for the identification of posttranscriptional RNA modifications, such as alternative splicing and RNA editing.

Results: Based on the nucleotide sequence information of transcripts, we identified 819 novel transcriptionally active regions (nTARs) and revised 906 incorrectly predicted gene models, including revisions of exon-intron structure, gene orientation and sequencing errors.

Fungal cytochrome P450 sterol 14α-demethylase (CYP51) and azole resistance in plant and human pathogens.

Azoles have been applied widely to combat pathogenic fungi in medicine and agriculture and, consequently, loss of efficacy has occurred in populations of some species. Often, but not always, resistance was found to result from amino acid substitutions in the molecular target of azoles, 14α-sterol demethylase (CYP51 syn. ERG11).

Development of a novel multiplex DNA microarray for Fusarium graminearum and analysis of azole fungicide responses.

Background: The toxigenic fungal plant pathogen Fusarium graminearum compromises wheat production worldwide. Azole fungicides play a prominent role in controlling this pathogen. Sequencing of its genome stimulated the development of high-throughput technologies to study mechanisms of coping with fungicide stress and adaptation to fungicides at a previously unprecedented precision.

Adaptation of Fusarium graminearum to tebuconazole yielded descendants diverging for levels of fitness, fungicide resistance, virulence, and mycotoxin production.

Azole fungicides play a prominent role for reliable plant disease management. However, quantitative azole resistance has been shown to develop in fungal pathogens, including Fusarium graminearum, the causal agent of Fusarium head blight (FHB). Due to widespread application of azole fungicides, resistance may accumulate to higher degrees in fungal field populations over time.

Chitin synthesis during in planta growth and asexual propagation of the cellulosic oomycete and obligate biotrophic grapevine pathogen Plasmopara viticola.

PCR amplification of two CHS gene fragments of the obligate biotroph Plasmopara viticola, the causal agent of downy mildew of grapevine, is described. While one fragment shows homology to fungal class IV chitin synthases, the other fragment groups with other oomycete chitin synthases to form a novel class of chitin synthases most closely related to class I-III. RT-PCR experiments indicate that PvCHS1 is constitutively expressed, whereas PvCHS2 is specifically transcribed in sporangiophores and sporangia.