The Moscou group based at The Sainsbury Laboratory centres their research efforts on understanding the genetic architecture underlying host adaptation to fungal pathogens of the Poaceae family. Current projects include multiple pathogen recognition at the Mla locus in barley and the role of multiple R genes maintaining immunity in barley to non-adapted stripe rusts.
The Wild Barley Diversity Collection (WBDC) has long been known to be a source of resistance against pathogens affecting barley, exhibiting substantial intraspecific genetic diversity to a diverse array of fungal pathogens. Pyricularia oryzae (teleomorph Magnaporthe oryzae) is the causal agent of blast disease. Isolates exhibit host specificity whereby they infect genetically analogous hosts, but a unique characteristic of the rice adapted P. oryzae is that it also shares barley within their host range.
An initial screening panel of the WBDC for resistance against P. oryzae identified several resistant accessions, including WBDC038. From this a mapping population was generated with the susceptible parent Manchuria. Phenotypic analysis of the population spot-inoculated with the P. oryzae isolate Guy11 indicated a 3:1 ratio for resistance:susceptibility (70:26), suggesting a single responsible gene. Visualisation of fungal hyphae growth by WGA-FITC stain under UV fluorescence demonstrated levels of resistance used when scoring phenotypes of inoculated leaves. Further to this, a comprehensive genetic map was assembled, isolating the region conferring resistance. Markers indicated genetic linkage on chromosome 4H and a new locus conferring resistance to P. oryzae. Further investigation into the function of this locus is yet to be carried out but it is a promising start to mining the WBDC for resistance to P. oryzae, and for further fungal pathogens on the Poaceae.
As our reliance on cereal crops becomes ever more important, and with increasing pressures on food production, novel resistance to pathogens that threaten food security will become an increasing priority of agricultural research. For this reason, the implications of this research are potentially far-reaching in their application in producing more robust cereal crops against fungal infections.
This period of research has given me a unique insight into how molecular plant-microbe interactions are investigated and the pathway for cereal crop improvements. I have developed a higher degree of sophistication in my scientific writing and experimental planning, alongside experimental techniques and independent laboratory experience. I was given the opportunity to present my research as a poster at the BSPP presidential meeting in September, consolidating my findings and development as a young scientist. This has given me a fantastic introduction to the scientific community as I begin to embark on my career in research.
Victoria Armer
University of Bristol