My research falls in to two broad areas, with the shared priority of building links between fundamental plant science and its application in sustainable agriculture and horticulture. My interest in interactions between plants and their natural enemies, invertebrate herbivores or pathogenic microbes, is founded on understanding the ecology of such interactions in non-crop systems (e.g. Senecio vulgaris and its rust Puccinia lagenophorae; Rumex spp. and their Uromyces rumicis and herbivores (especially the beetle Gastrophysa viridula)). My interest in the ecology and physiology of these systems has expanded to build links between ecological studies of defence (especially defence against multiple enemies) and molecular research into similar topics. These cross-disciplinary studies have formed the foundation of more applied research in to new approaches to pest and disease control in sustainable agriculture. My interest in the effects of solar UV radiation on plants and their associated organisms was originally stimulated by concerns over stratospheric ozone depletion, which increases the intensity of UV-B radiation reaching the biosphere. Ozone depletion remains a significant environmental issue, despite the undoubted success of the Montreal Protocol, and I am a member United Nations Environment Programme (UNEP) panel on the interactive effects of ozone depletion and climate change on health and the environment, which continues to provide up-to-date assessment of this topic for governments and policy makers. Much of my current research in to UV radiation now has a strong applied thrust, seeking to exploit biological responses to UV, in crops and their pests and pathogens, in sustainable horticulture.