Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

This project will establish the science underpinning our recent discovery that soaking seeds of plants in plant defence hormones confers long-lasting pest resistance in plants grown from these seeds. It will investigate the fundamental mechanisms behind priming of defence against pests and diseases by seed treatments with jasmonic acid (JA) and the nonprotein amino acid, beta-aminobutyric acid (BABA). The primary objectives are: 1. To determine the extent to which JA and BABA seed treatments directly stimulate defence even without any biotic attack, and the extent to which they act via priming. This objective will be achieved by investigating (i) transcriptional profiles, and (ii) profiles of volatile emissions, in control and seed-treated plants before and after pest attack. 2. To examine the contribution of chromatin remodelling and DNA methylation to the priming of defence-related genes in seed-treated plants. 3. To investigate the impacts of seed treatments with JA and BABA on (i) direct defences against herbivores, (ii) indirect defences against herbivores, and (iii) pathogen resistance. 4. To test the hypothesis that JA and BABA act independently, providing additive (or even synergistic) effects on defence when used as a combined seed treatment. The project will generate data relating to plant responses to JA and BABA seed treatments at three levels: gene expression, volatile emission and susceptibility to insect attack. Molecular and biochemical changes will be compared between primed and un-primed plants with and without subsequent infestation by insects. Insect bioassays will put the observed changes in gene expression and volatile emission in an ecological context, both in terms of interactions with herbivores and in terms of tritrophic interactions with natural enemies of the herbivores.

Research in this project is focused on the movement ecology and spatial patterning of populations of pests (insects & pathogens) and beneficials (natural enemies & pollinators). Many pests and their natural enemies are highly mobile (which affects their ability to colonise and damage crops), while the quantity and quality of seed and fruit production in many crops is dependent on the spatial structuring of the crop and the movement patterns of pollinators. This project seeks to tackle all aspects of spatial scaling from national and regional dynamics through to landscape and farm-scale patterns and individual movements, in an attempt to better understand how sustainable food production and high levels of biodiversity can co-exist in agricultural landscapes. The research tackles the following questions: 1. Are invasive species and their migration pathways predictable, and can models be developed that elucidate a mechanistic understanding of observed spatial patterns of pests? 2. Do pest species exhibit spatial synchrony over large scales, and does this synchrony facilitate area-wide suppression given additional management interventions? 3. At what scale should pests, pathogens and natural enemies be managed (monitored and controlled) for maximum yield? 4. Does the spatial patterning of floral resources of differing nutritional quality affect the search strategies, foraging success, colony fitness and pollination services of bees? 5. How do sub-lethal infections of diseases and parasites affect the navigational capabilities, foraging success, and fitness of infected versus uninfected hives? These questions will be tackled with a variety of approaches, including exploitation of Rothamsted’s long-term datasets and classical experiments; purpose-built entomological radars for studying long-range migration and short-range foraging movements; and mathematical models to predict and explain spatio-temporal dynamics in pest and beneficial populations.

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.

Aim: To establish the mechanisms by which plant and invertebrate communities function in the arable ecosystem to maintain a) productivity of crops and b) survival and resilience of non-cropped biodiversity. Approach: Research in this project will test the hypothesis that trait-based, genetic and behavioural mechanisms can be used to predict evolutionary and functional responses to changes in land management, habitat diversity and spatial and temporal resource availability. The project brings together Rothamsted's work on the role of arable plants, pollinators, herbivores and their natural enemies (pathogens, predators and parasitoids) in the ecological functioning of arable landscapes, building primarily on Rothamsted's strength in studying multi-trophic interactions at a variety of spatial scales. Objectives: 1. Use a functional trait approach to predict the response of arable plant communities to changes in land use and management and the resulting effect on the ecosystem functions they perform including support of beneficial biodiversity. 2. Examine strategies of resource exploration and exploitation by pests and beneficial organisms (pollinators and natural enemies) within farmland, to predict patchy resource utilisation over space and time. 3. Measure how pollination and the spatial dynamics of pollen flow in crops and wild plants are affected directly by landscape context and management; and indirectly by the effects of these drivers on pollinator abundance and behaviour. 4. Test whether the stability of natural enemy communities is increased by habitat diversity (allowing co-existence by niche differentiation) and if the distribution of pests and their natural enemies can be predictably manipulated by habitat management to enhance pest control.