Susceptibility to the fungal plant pathogen Austropuccinia psidii is related to monoterpene production in Australian Myrtaceae species

Abstract In 2010, the fungal plant pathogen that causes Myrtle rust, Austropuccinia psidii , which is native to South America, was first detected in Australia and has since had significant impacts on several Australian Myrtaceae species. Despite this, our understanding of role secondary metabolites play susceptibility A. limited. This study aimed determine: (1) whether metabolite (phenolics, terpenes) production induced after inoculation if so, (2) how their relates susceptibility. To test these aims, we selected seven species have a wide range within-species variability . We found five significantly increased either phenolic or sesquiterpene post-inoculation suggesting pre-inoculation levels were not sufficient combat infection. The two ( Angophora costata Corymbia citriodora ) did increase tended greatest amongst Interestingly, across all species, monoterpenes only reduce contributes limited light findings, future research should aim identify biomarkers (e.g. individual chemical compounds) confer resistance so individuals with can be utilised commercial conservation projects.