P-435 - Developing broad bean as a new model system for studying plant immunity

The study of molecular plant immunity using transient Agrobacterium-mediated expression is currently reliant on two key model species, Nicotiana benthamiana and Arabidopsis thaliana. Whilst these species have proven to be highly amenable to a range of molecular techniques, we lack an understanding of how well conserved immune functions are across the rest of the diversity of angiosperms. In this work, we aim to develop broad bean as a new model species for transient assays as a representative member of the globally important plant family Fabaceae (legumes). Using a synthetic biology approach, we optimise transient Agrobacterium-mediated expression in this species and demonstrate that our system can be used to study the function of nucleotide binding and leucine rich‐repeat immune receptors (NLRs). Using recently published genomic data, we characterise the NLR repertoire of broad bean and show that we can test endogenous NLR function by transient cell death assays. We also propose broad bean as a test bed for studying the interspecific transfer of NLRs, showing that several Solanaceae-specific helper NLRs function and cause cell death in this species. This work will help to establish broad bean as a new, amenable model for understanding immune function in Fabaceae to facilitate future biotechnological approaches for enhancing disease resistance in legume crops.