International Symposium on Cereal Leaf Blights 2019 | University College Dublin, Ireland | 22-24 May 2019

PHOTOPROTECTION PLAYS A KEY ROLE IN DEFENCE AGAINST ZYMOSEPTORIA TRITICI IN WHEAT


Olubukola Ajigboye
University of Nottingham

Dasuni Jayaweera
University of Nottingham

Erik Murchie
University of Nottingham

Rumiana Ray*
University of Nottingham


Oral Presentation
Host-Pathogen Interactions

Moore Auditorium, UCD O'Brien centre for Science
23 May 2019, 11:40

View this abstract online by visting isclb2019.com/see/ABS15591

Septoria tritici blotch (STB), caused by Zymoseptoria tritici, is the most destructive foliar disease of wheat. Optimal chemical control can be challenging due to the widespread fungicide resistance in the fungal pathogen populations. Thus, improving varietal resistance is the most sustainable and economical method for future STB disease control. Chloroplast photoprotection plays a critical role in plant responses to environmental stress. In this work, we aimed to determine the role of photoprotection in the early disease response and resistance to STB. Two winter wheat cultivars that differ in photoprotective responses to STB were spray-inoculated with Z. tritici at growth stage 19. Components of photoprotection including non-photochemical quenching (NPQ) of chlorophyll fluorescence, carotenoids, reactive oxygen species (ROS), and the expression of genes implicated in ROS detoxification were quantified at 0, 8 and 24 hours post inoculation (hpi). Early defence responses to Z. tritici at 8 and 24 hpi were associated with slow relaxing (qI) NPQ and significant upregulation of genes encoding ROS scavenging specific to the chloroplast and the accumulation of carotenoids. Our results show that photoprotective mechanisms originating in the chloroplast are crucial in plant defence against Z. tritici. Further elucidation of the underlying molecular and genetic mechanisms can facilitate breeding of new genotypes with improved durable resistance to STB as well as to other important foliar crop pathogens.