Watch Professor Nicola Spence talk on protecting the UK from plant pests and diseases at the 2018 John MacLeod lecture

Protecting the UK from plant pests and diseases: this year's topic in more detail

The plants and trees of this country are precious natural resources. They contribute to our food supply, our rural economy, and are essential to the biodiversity of the country. They shape the landscape, provide timber, form part of our heritage and support our health and wellbeing providing much enjoyment. Yet the threat to the health of our plants and trees from pests and diseases is real and increasing. Globalisation of travel and trade and demands for a greater variety of plant species mean threats are ever-present. While we cannot eliminate all threats from occurring, we can strengthen protection, minimise impact and enhance the ability of our plants and trees to resist pressures.

In the UK we have worked hard to earn a global reputation for highest standards of biosecurity for plants and trees. We have established a risk-based approach, world-leading science and research, enhanced protection, surveillance and inspection. Yet the threat level is constantly evolving and we must take further action to keep pace with changing threats. By working collectively we can minimise the risks and strengthen our approach from potential threats such as Xylella and Emerald Ash Borer. We all have a part to play to limit the spread of pests and diseases through simple actions when travelling, buying plants or visiting our woodlands and parks.

Professor Nicola Spence: this year's speaker in more detail

Professor Nicola SpenceNicola Spence is DEFRA's Chief Plant Health Officer, Deputy Director for plant and bee health and is an expert in plant health and international plant trade.

Previously Head of Plant Health and Chief Scientist at the Food and Environment Research Agency, Nicola is an experienced research scientist and has worked on virus diseases of horticultural crops in the UK and internationally.

She is Vice President of the British Society of Plant Pathology, President of the European Foundation of Plant Pathology, Visiting Professor in Plant Pathology at Harper Adams University, a member of Court at the University of York and a Trustee of The Yorkshire Arboretum.

She has a BSc in Botany from the University of Durham, an MSc in Microbiology from Birkbeck College, University of London and a PhD in Plant Virology from the University of Birmingham.

History of the John MacLeod annual lecture

Launched and hosted for two years at the RHS Lindley Hall in London, the John MacLeod Annual Lecture was created to highlight important and inspiring topics on horticultural science. A broad audience of RHS members, scientists, policymakers and the media is invited every year to hear luminaries of the scientific field give talks on major research projects or new areas of thought. 

Catch up on previous lectures: watch our YouTube playlist

The late professor John MacLeodWho was Professor John MacLeod?

The lecture's namesake, Professor John MacLeod, who died in 2010, was a plant scientist and Professor of Horticulture at the RHS. He was also chairman of the RHS Scientific Committee and was a powerful advocate for horticultural science. He was acutely aware of its pressing relevance in sustaining the natural environment and world food supplies.

Watch previous John MacLeod lectures on our YouTube playlist


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