Jamie Waterman


PhD Candidate

Thesis Title

Using Simulated Herbivory to Mechanistically Understand Inducible Specialised Metabolites and Silicon-based Plant Defences

Research Project

Silicon (Si) is the second most abundant element in earth’s crust and is thus ubiquitous in soil systems. This considered, certain classes of plants have evolved the ability to uptake and transport Si between tissues. Nevertheless, the functional role of Si in plant biology remains ambiguous.

Although it has been well documented that Si may modify chemical defence capabilities of plants, the mechanisms through which this is achieved have not been well documented. Further, when a plant is attacked by an insect herbivore, numerous stimuli are introduced such as mechanical stimulation, wounding, and chemical elicitation from both insect- and microbial symbiont-derived compounds. Using simulated herbivory techniques (see Waterman et al., 2019 (opens in a new window) ), I will investigate the role of Si in defence responses against each of the aforementioned stimuli in order to understand the mechanisms through which Si helps to confer resistance against herbivore attack. Additionally, Si might also assist with defence against herbivory by acting as a physical barrier, abrading the insect alimentary tract and/or hindering nutrient absorption; beyond solely chemical defences, I will attempt to realise the influence of Si on the nutritional qualities of plant tissue. By identifying the functional role of Si in mediating plant defences, it may be possible to determine the evolutionary basis for the accumulation and transport of Si by plants, and may help to inform useful pest mitigation strategies that avoid the use of costly and potentially harmful chemical treatments.


Waterman JM, Mann TJ, Cazzonelli CI, Hartley SE, Johnson SN, (2020) 'Microbes in Helicoverpa armigera oral secretions contribute to increased senescence around plant wounds', Ecological Entomology (in press)

Hall CR, Dagg V, Waterman JM, Johnson SN, (2020) 'Silicon alters leaf surface morphology and suppresses insect herbivory in a model grass species', Plants, vol.9, no.5, Article no.643

Hall CR, Waterman JM, Vandegeer RK, Hartley SE, Johnson SN, (2019) 'The Role of Silicon in Antiherbivore Phytohormonal Signalling', Frontiers in Plant Science, vol.10, Article no.1132

Waterman JM, Cazzonelli CI, Hartley SE, Johnson SN, (2019) 'Simulated Herbivory: The Key to Disentangling Plant Defence Responses', Trends in Ecology & Evolution, vol.34, no.5, pp 447-458


Assoc. Prof. Scott Johnson, Dr. Chris Cazzonelli, Prof. Susan Hartley (University of York)