Elucidating the agro-ecological factors influencing virus success in cereal ecosystems (Royal Commission for the Exhibition of 1851; 1851 Research Fellowship; 2022 - 2025; PI; Liverpool University)


Project Overview
Cereal crops are grown for human consumption, livestock feed, and alcohol production. Herbivorous insects and plant diseases can significantly reduce crop yields, threatening food security. Barley yellow dwarf virus (BYDV) is a devastating cereal virus, with significant levels of infection reducing crop yields by up to 80%. BYDV is vectored by aphids, small phloem-feeding insects who’s needle-like mouthparts make them optimal virus vectors. In natural ecosystems individuals of all species are affected by others around them and these interactions can have wide-reaching consequences for organism biology and ecology. Despite this, virus-vector-host interactions are rarely studied in an ecosystem context and this lack of understanding limits the extent to which we can exploit natural processes to better manage virus infection. Studying interactions in a wider ecological context is important as subtle changes in the virus-vector-host system could have far-reaching consequences on vector behaviour and virus transmission. Aphid populations are genetically-diverse and host multiple endosymbiotic bacteria that confer dynamic benefits to host populations, including behavioural traits that could impact virus-vector biology; however, it is currently unknown if this diversity alters virus transmission ability. Additionally, vector-resistant plant varieties are often used to combat disease, although the bottom-up effect this has on the structure and behaviour of insect vector populations, and the knock-on impact on the spread of plant viruses in the local ecosystem, is unknown. It is also unknown to what extent the wider agro-ecological system, such as the presence of the natural predators and parasitoids of vector populations, exerts a top-down influence on the virus-vector-plant relationship, and whether this impacts virus transmission and success.

Filling these fundamental knowledge gaps will unravel the biological and ecological processes that underpin virus-vector-host interactions and will help us develop innovative and novel nature-based pest and disease management solutions. This fellowship will deliver this knowledge through three research objectives, each comprising a question centred on a fundamental knowledge gap. 1) How is virus transmission affected by insect vector diversity?; 2) To what extent does plant diversity influence the vector-virus relationship?; 3) Do natural enemies exert a top-down influence on the virus-vector-plant relationship and virus success? 
New pump-prime funding from Liverpool University to identify molecular processes behind differential virus transmission
In Jan 2023 I was awarded pump-prime funding from Liverpool University for an RNA-sequencing project: "Elucidating the bio-molecular drivers behind differential virus transmission efficiency in an endosymbiont-aphid-virus system". This project will build on recent observations of differential virus transmission across multiple aphid clones by attempting to identify the underlying molecular processes. This will directly support my ongoing 1851 fellowship project.

Publications


Genetic diversity in vector populations influences the transmission efficiency of an important plant virus


Daniel J. Leybourne, Mark A. Whitehead, Torsten Will

Biology Letters, vol. 20, 2024, p. 20240095


To tolerate drought or resist aphids? A new challenge to plant science is on the horizon


CC Ramirez, PE Gundel, AJ Karley, DJ Leybourne

Journal of Experimental Botany, 2023