Brendan Delroy

Candidature

PhD Candidate

Thesis Title

Effects of Arbuscular Mycorrhiza on the accumulation of Salicylic Acid in B. distachyon root systems

Research Project

Arbuscular mycorrhiza (AM) is a mutualistic symbiotic association that occurs between most terrestrial plants and fungi of the phylum Glomeromycota. While most renowned for its function of resource exchange between symbionts, the association is also capable of performing a number of secondary functions, such as the ability to suppress pathogen infection of the host plant. However, our current mechanistic understanding of pathogen-AM interactions is still quite limited, not only as to how AM influence and suppress pathogen infection, but even more so as to how pathogens influence AM associations. My area of research focuses on this latter, novel approach aimed at improving our understanding on the influence pathogens might play in altering plant-AM interactions which could play a role in shaping AM fungal communities over time.

I aim to identify pathogen-mediated alterations of host plant physiology which influence the interactions that occur between the host plant and its AM fungal partners and to determine if AM fungal taxa are differentially affected. Such work might highlight pathogen stress upon a host plant as a selective force that plays a role in structuring the local AM fungal community over time. This is significant in that such a structural shift may have implications on the functional capacity of the community. For example, pathogen stress upon a host plant may select for AM fungi most capable at providing the host with pathogen protection at the expense of AM fungi more capable at nutrient uptake. As a result, we might expect to observe a functional shift within the AM fungal community over time.  A better understanding of this potential pathogen influence might help predict how AM fungal communities respond within systems afflicted by particular pathogens, an important consideration for future efforts aimed at employing AM associations in agricultural strategies intended to improve crop yields.

Publication

Donn S, Kawasaki A, Delroy B, Chochois V, Watt M, Powell JR, (2017) 'Root type is not an important driver of mycorrhizal colonisation in Brachypodium distachyon', Pedobiologia, vol.65, pp 5-15

Research Supervisors

A/Professor Jeff Powell, Dr Alexie Papanicolaou