Wheat blast: histopathology and transcriptome reprogramming in response to adapted and nonadapted Magnaporthe isolates.
* Blast disease (causal agent Magnaporthe oryzae) has presented as a new and serious field disease of wheat in South America. Here, we investigated the responses of wheat to both adapted and nonadapted isolates of the blast fungus Magnaporthe, examining cellular defence and transcriptional changes. * Resistance towards the nonadapted isolate was associated with the formation of appositions, here termed halos, beneath attempted Magnaporthe grisea penetration sites that wheat-adapted, M. oryzae isolates were able to breach. * Transcriptome analysis indicated extensive transcriptional reprogramming following inoculation with both wheat-adapted and nonadapted isolates of Magnaporthe. Functional annotation of many of the differentially expressed transcripts classified into the categories: cell rescue and defence, plant metabolism, cellular transport and regulation of transcription (although a significant number of transcripts remain unclassified). * Defence-related transcripts induced in common by adapted and nonadapted isolates were differentially regulated in response to M. oryzae and M. grisea isolates over time. Differential expression of genes involved in cellular transport indicated the importance of this process in plant defence. Functional characterisation of these transcripts and their role in defence may eventually lead to the identification of broad-spectrum resistance mechanisms in wheat towards Magnaporthe.
Tufan
Hale A
HA
Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Colney Lane, Colney, Norwich, Norfolk, NR4 7UH, UK.
McGrann
Graham R D
GRD
Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Colney Lane, Colney, Norwich, Norfolk, NR4 7UH, UK.
Magusin
Andreas
A
Department of Computational and Systems Biology, John Innes Centre, Norwich Research Park, Colney Lane, Colney, Norwich, Norfolk, NR4 7UH, UK.
Morel
Jean-Benoit
JB
UMR BGPI INRA/CIRAD/SupAgro, Campus International de Baillarguet, T41/K34398 Montpellier, France.
Miché
Lucie
L
UMR BGPI INRA/CIRAD/SupAgro, Campus International de Baillarguet, T41/K34398 Montpellier, France.
Boyd
Lesley A
LA
Department of Disease and Stress Biology, John Innes Centre, Norwich Research Park, Colney Lane, Colney, Norwich, Norfolk, NR4 7UH, UK.
D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D020082:Magnaporthe / Q000302:isolation & purification / Q000472:pathogenicity*; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D013020:South America; D014908:Triticum / Q000235:genetics* / Q000382:microbiology