Scientists at the University of Strathclyde are working with partners to tackle one of the most damaging bacterial plant diseases in the UK, responsible for annual losses of £50m for the potato industry.

The interactions between the pathogen Pectobacterium atrosepticum and free-living nematodes in the development of blackleg is at the heart of a £2m research project funded by the Biotechnology and Biological Sciences Research Council (BBSRC), Natural Environment Research Council (NERC), Defra and Scottish Government.

The project is being led by the James Hutton Institute with collaborators from the National Institute of Agriculture Botany at Cambridge University Farm, the universities of Dundee, Durham, Glasgow, Newcastle, Strathclyde and industry partners Bayer Crop Science, SA Consulting, Scottish Agronomy, Soil Essentials and SASA. AHDB will play an important role in the project’s knowledge exchange through its Farm Excellence Platform.

Contaminated seed

Project leader Professor Ian Toth, of the JHI’s Cell and Molecular Sciences department, believes scientists have the possibility of making a step change in the way blackleg is managed.

“Blackleg that appears in a ware crop may not necessarily be due to the contaminated seed, but to infection directly from the environment; something that could be managed at a local level rather than just with the seed producer,” he said.

Previous research has shown that when free-living nematodes are present in soil, a significant increase of blackleg-causing bacteria occurs in the stems of potato plants, highlighting an important association between these two groups of organisms.

“Currently there is a knowledge gap in the management of blackleg, and we wish to address it by characterising the identity and distribution of nematodes, and the ways in which they associate and interact with the blackleg pathogen,” Prof Toth added.

“We also want to identify how and where on the plant infection takes place, and whether the management of nematodes might help to reduce blackleg infection.”

Strathclyde’s Professor Adam Kleczkowski, of the Department of Mathematics and Statistics, will lead work package five and will work with colleagues at AHDB and FERA to assess the levels of uptake by end-users.

Support tool

Professor Kleczkowski said: “One of the project aims is to develop a decision support tool, DST, for use by potato growers throughout the UK. However, for such a tool to create impact, it needs to be widely implemented.”

Based on the interactions with key stakeholders, the team will use epidemiological and bioeconomic modelling with input from social science to assess the end-user willingness to engage with the DST and to analyse the impact of partial uptake on the success of the implementation.

Recent modelling using the Scottish Government’s in-house potato inspections database shows that blackleg incidence on a national scale does not occur randomly, but in clusters.

Using data generated from this project, an extensive array of data from other recent and historical investigations and the latest data from government and industry, another aim is to identify trends and drivers of blackleg incidence in both space and time and, through this, produce predictive models to support the development of a set of decision support tools for growers.

“Through further testing, we will quantify the predicted effects of climate change on future blackleg incidence in association with free-living nematode presence and a range of other factors including soil moisture and planting and harvest dates, thus providing the industry with robust and novel data to underpin their sector resilience planning,” Prof Toth added.

The project Building a Decision Support Tool for Blackleg (DeS-BL) will run from 2020 to 2023 and more information can be found on Scotland’s Plant Health Centre website.