Temperature regulation of non-coding RNA networks and plant-microbe communication in the rhizosphere

Plants manipulate the rhizosphere by releasing compounds known collectively as root exudate. Root exudate can recruit beneficial soil microflora and fauna; however, it can also attract parasites and pathogens, with implications for plant health and yield. Our data demonstrate that temperature alters tomato root exudate composition, which affects the hatching and attraction of plant parasites and microbes. Transcriptomic data reveal a range of microRNAs and predicted target genes that are asymmetrically differentially expressed in developmentally-matched tomato seedlings grown at different temperatures (18 - 23 - 28 degrees C). We hypothesise that these microRNAs and target genes contribute to the modification of root exudate composition and altered interactions with parasites and microbes. We will address this hypothesis by validating microRNA-target interactions, followed by functional analysis using transgenic microRNA over-expression and inhibition lines. Transgenic lines will be used to establish the impact that individual microRNAs have on plant-rhizosphere interactions, by collecting root exudates, and using molecular and behavioural assays to assess parasite and microbe behaviours. Target genes will be functionally assessed using transgenic RNAi lines, and correlated with rhizosphere interactions. Exudate composition will be assessed using metabolomics, and selected exudate compounds will be tested for behavioural impact on parasites / microbes.

This project will be supervised by Dr Johnathan Dalzell and Dr Fuquan Liu of Queen’s University School of Biological Sciences.

Start Date: 1 October 2020
Duration: 3.5 years