Wheat homologues of BAK1 contribute to basal resistance against Zymoseptoria tritici and Fusarium graminearum
W. LEE (1), J. Rudd (1), K. Hammond-Kosack (1), K. Kanyuka (1) (1) Rothamsted Research, United Kingdom

The two ascomycete fungi Z. tritici and F. graminearum are economically important pathogens of wheat world-wide, causing Septoria tritici leaf blotch (STB) and Fusarium head blight (FHB) diseases, respectively. Although the infection biology of both pathogens has been well characterised, the mechanisms behind either resistance gene-mediated or basal defence against either pathogen are not well understood. In Arabidopsis, the leucine-rich repeat receptor-like kinase (LRR-RLK) BAK1 is an important regulator of Pattern Recognition Receptor (PRR)-triggered immunity (PTI) and is known to be involved in defence against a range of bacterial, oomycete and fungal pathogens. BAK1 regulation of PTI depends on interactions with a number of other LRR-RLKs, including BIR1 and SUPPRESSOR OF BIR1 (SOBIR). BAK1 also appears to be required for the function of LRR-receptor-like immune receptor proteins (LRR-RLPs). It is currently unknown whether functional homologs of these genes exist in wheat. We have identified at least 3 candidate wheat BAK1 genes, two of which (TaBAK1-2L and TaBAK1-6L) are up-regulated during Z. tritici infection. Using BSMV-VIGS to silence these genes, we show that leaves and ears of susceptible silenced plants support higher levels of Z. tritici and F. graminearum infection, respectively. These data suggest that BAK1 and therefore probably as yet unknown interacting surface receptor(s) also contribute to basal resistance in wheat against these fungal pathogens. 

Abstract Number: P18-680
Session Type: Poster