Agriculture

With plentiful rain and long summer day lengths, Scotland producing some of the highest yielding and best quality crops in the world. But conditions that promote good crop growth are often good for pests and pathogens too and in Scotland 15-20% of our crops are lost to pests and diseases annually. 

These losses to pests and diseases   amount  to almost a million lost tonnes per year with a value close to £200 million. Dealing with the endemic disease burden  inevitably means higher prices in supermarkets, hard times for growers  and a knock to the economy but, in addition to this current burden  many more pests and pathogens are arriving or threatening our borders.  Priority concerns for the sector are sustainable methods of reducing and managing pest and disease risks that lessen reliance on pesticides. Current acute issues which have been highlighted by stakeholders  are pesticide resistance developments in some of our endemic pests and diseases, and also concerns over product withdrawals through the regulatory processes. Concerns over resistance development in endemic diseases are a major plant health concern in many crops in the agriculture sector. Potato blight and ramularia in barley being two current example where new issues emerged in 2017.

 

Projects

Project Lead: Rehema White
We have commissioned a project to review and further develop the PHC’s Communications Strategy to help develop further networks and collaborations, while building on existing relationships to improve knowledge flows in relation to plant health across Scotland. This project will draw on and align with previous and ongoing PHC research projects and will address:

1. What is the overall goal and vision for PHC and how do we articulate this for different groups and sectors?
2. What do we want to communicate, when and to whom?
3. How do we want to communicate to different audiences and for these different purposes?
4. How do we optimise budget and human resource in communicating about plant health?

Impact: The outcome of this project will be a Communication Strategy outlining the goal of communication, roles and responsibilities and a process, including an annual cycle of reflection to permit update or modification on a regular basis and linking to the communication matrix.
Project Lead: Peter Skelsey
Potato Cyst Nematode (PCN) is a threat to the Scottish seed potato and bulb industries: SASA estimates that over 13% of the area regularly planted with potatoes in Scotland is now infested with PCN, with an estimated increase in spread of 5% per year. Recently, following a working group on PCN, a report entitled ‘Potato cyst nematode (PCN) and the future of potato production in Scotland’ was submitted to Scottish Government highlighting the PCN problem in detail and outlining practical recommendations for its reduction. However, in order to maximise and target resources for such a reduction, a better understand is needed of i) the main areas of infestation in Scotland and how this is changing over time, ii) what key factors are responsible for that spread (be it geographic, climatic, agronomic etc) and iii) which management options would allow us to make the biggest impact on reducing spread.

Impact: The outcomes of this project to provide guidance to both policy and industry on the most effective ways to reduce spread of PCN.
Project Lead: Ashleigh Holmes
To maximise the impact of the work of the Centre, we need to be effective at the production, exchange and implementation of plant health knowledge across the four plant sectors, forestry, horticulture, environment and agriculture. To this end we have had a Stakeholder Engagement Strategy developed (PHC2020/02). This project, that runs for a 12-month duration, will implement this strategy. The aims of the project are to conduct further research on plant health knowledge flows, develop the Centre’s relationship with plant health stakeholders, foster a more dominant social media narrative for the Centre and lead the translation and distribution of knowledge to plant health practitioners, liaising closely with SEFARI Gateway.

Impact: Keep plant health and biosecurity at the forefront of our stakeholders’ minds, and a high priority for them, raising stakeholder awareness about the risks from plant pests and pathogens and the solutions available for their management and control, and raising the profile of the Plant Health Centre and our online resources.
Project Lead: Elliot Meador
Pesticide use remains an important tool in managing pest, weed and disease risks to crops and maintaining profitable production. There are several drivers, including pesticide withdrawals and the biodiversity and climate crises, for reducing reliance on pesticides and promoting the uptake of more sustainable practices through Integrated Pest Management (IPM). This project looks to understand where growers and agronomists currently gather information to form their impression of pest and disease risk and inform their decision making on the need for interventions, pesticide or otherwise. It will interrogate whether perceived risk and pesticide application made match the actual risk to crops.

Impact: Identify accurate, efficient and trusted sources and test whether these sources are influential in appropriate usage of control options across key arable regions and crop types, plus intervention tools or methods that might be needed to manipulate or change how information flows; bespoke to the needs of the Scottish stakeholder network.
Project Lead: Daniel Chapman
Xylella fastidiosa is a bacterial plant pathogen that can cause disease in a broad range of hosts. There are currently major Xylella outbreaks in Southern France, including Corsica, Italy, mainland Spain and the Balearic Islands. Although Xylella has so far not been detected in Scotland (or UK), an outbreak would have serious impacts on any host plant-related activities/businesses and the wider environment. To understand the risk posed to Scotland’s plants from Xylella, and to be adequately prepared if it is detected, there are important knowledge gaps that must be addressed. This project will build on the results of the previous PHC Xylella projects (PHC2018 / 04 /05 / 06) to further refine Scottish Government’s contingency and preparedness measures for the possible arrival of Xylella fastidiosa.

Impact: Deliver recommendations as to the suitability of vector trapping methods and eradication strategies, if deployed in Scotland.
Project Lead: Jim Wilson
Poor control of groundkeepers (unharvested potatoes that regrow during subsequent crops) enables PCN populations, along with other pests and pathogens, to increase between potato rotations. This greatly undermines the usefulness of rotations in reducing PCN in the soil. A reduction in groundkeeper occurrence, through better control, would have a major impact on the presence of PCN. However, the potential loss of the herbicide glyphosate to control groundkeepers, especially alongside other herbicide withdrawals, will make control more difficult and costly. To control groundkeepers, it is first necessary to know where they are, what factors lead to increased incidence, how to detect them and how effective different control options are.

The aim of this small project is to use aerial imagery from drones equipped with RTK GNSS to repeatably locate groundkeeper potato plants, coupled with soil samples from areas with and without groundkeepers, testing for PCN levels in the soil samples. Results will be mapped and analysed to compare the effect of groundkeepers on PCN. The results from this work will feed directly into the new SG funded PCN project.
Project Lead: Fiona Burnett
The use of pesticides to control plant pests and diseases is a key management intervention across plant health sectors, particularly in agriculture, horticulture, and commercial forestry. Pesticide withdrawals through legislation, coupled with increased insensitivity, have emerged as key concerns for Scottish plant health stakeholders. To meet this stakeholder need, the PHC commissioned a project to quantify the impacts on Scottish plant health arising from pesticide withdrawals and set this in the context and time frame of alternative management tools (PHC2018/15: Potential Impacts Arising from Pesticide Withdrawals to Scotland’s Plant Health). The key outcomes from this project are that for all the plant health sectors (as above and including natural environment) the withdrawal of key substances will have a significant impact on the ability to manage pests, weeds, and diseases effectively and economically. For soft fruit and field vegetables in particular, production will be significantly affected and may become uneconomic. This project builds on data and results from this previous PHC project and will use case studies to understand likely impacts and their mitigation.
Project Lead: Ian Toth
The potato industry in Scotland employs over 2000 people and is worth £250 million to the economy. However, the industry is under serious threat from Potato Cyst Nematode (PCN). PCN comprises two closely related species, Globodera rostochiensis and Globodera pallida, both of which are present in Scotland and, in recent years, the incidence of G. pallida has increased markedly. The use of commercial varieties with resistance to G. rostochiensis have largely halted its spread but there are few varieties with resistance to G. pallida. Statutory testing data collected by SASA shows that the area of land recorded as infested with G. pallida is doubling every 7–8 years and now accounts for nearly 70% of findings. SASA estimates that over 13% of land for growing potatoes is infested with PCN with an estimated increase in spread of 5% per year.

Following a Ministerial round table meeting on PCN in June 2020, the PHC were asked by the OCPHOS to form a working group to identify a clear strategy for dealing with the PCN crisis.
Project Lead: Mariella Marzano
The UK and Scotland have ambitious tree planting targets, with a major driver being carbon sequestration. Scotland’s Forest Strategy outlines a target of 15,000 ha per year. In addition to carbon management, other major drivers for tree planting are commercial forestry, habitat restoration and the establishment of new woodlands for biodiversity and amenity value. Scotland’s Forest Strategy outlines a target of 3,000-5,000 ha of new native woodland per year, and restoration of an additional 10,000 ha of native woodland. This involves planting a large volume of trees. There is considerable uncertainty as to where and how this volume of trees will be sourced, and associated uncertainty as to the biosecurity threats posed. The aim of this project is to improve our understanding of current biosecurity awareness and practices within the arenas of woodland creation/ expansion and habitat restoration in Scotland.

Impact: Determine the main barriers to ensuring that future planting for environmental restoration and conservation will minimise plant health risks.
Project Lead: Mariella Marzano
Large scale infra-structure projects such as transport networks and major housing projects typically include extensive landscaping and planting programmes. These operate at a large scale, often require instant visual impacts (semi-mature shrubs and trees) and face significant cost pressures. The modest scale of domestic production creates challenges in obtaining material from local sources, which can favour low-cost large-scale plant imports with associated risks of pest and disease entry. This project will fill in key knowledge gaps with those responsible for selecting, procuring and planting plants and trees on a large-scale to provide an understanding of how/whether biosecurity features in their decision-making and make recommendations for any changes required to improve bio-secure practices.

Impact: Provide Scottish Government policy with an assessment of the major biosecurity pitfalls and opportunities arising from large-scale landscaping plantings.

Publications

Forestry, Horticulture, Agriculture, Environment | Final Report and Policy Document

A targeted analysis of the impact of insecticide withdrawals in Scotland, in the context of alternative control options

July 2023

Insecticides are commonly used in Scottish agricultural, horticultural, forestry production, and for amenity and natural environment management purposes.  Over the last 10 years, approximately 50% of UK insecticide active substances have been withdrawn due to increasing concern over human health and environmental impacts.  Some of these losses will be mitigated by using alternatives but their practicality and cost under Scottish conditions is unknown.  This project analysed current crop production patterns and insecticide use in combination with how likely different insecticides are to be withdrawn and provided stakeholder views on the impacts of any such losses on their industry, including other control methods that may be adopted.

PHC Annual Report 2022-2023

July 2023

The Plant Health Centre works with Scottish Government, public bodies and stakeholders to provide scientific evidence to help them make important decisions about pests and pathogens that threaten Scotland the most.  Over the past 12 months we have delivered a consistent programme of stakeholder engagement and project commissioning, which are detailed in our annual report. 

Forestry, Horticulture, Agriculture, Environment | Final Report and Policy Document

Biosecurity practices to support plant health: a review of knowledge and practice

March 2023

This research investigated plant biosecurity risks from site visitors, tools & equipment, and large machinery. In addition to reviewing published guidance, UK businesses and organisations were engaged via questionnaires and interviews to explore how these aspects of biosecurity are understood and what procedures may be in place to address them.

Agriculture | Final Report and Policy Document

Modelling the spread of PCN in Scotland

Authors: Peter Skelsey
March 2023

Potato cyst nematodes (PCN) cost Scottish agriculture over £25 million/year and threatens food security in the developed and developing world. Improved understanding of PCN epidemiology is a priority for the Scottish potato industry, with spatial and temporal modelling identified by the recent PHC PCN working group as essential components.

Enhancing the Plant Health Centre’s communication with stakeholders

February 2023

This project was commissioned to implement a selection of the recommendations made in the PHC stakeholder engagement strategy and communication plan. The team developed strategies to manage time and resources of the Plant Health Centre more efficiently regarding communication of outputs, general information on activities, aims and current issues related to plant health.

Horticulture, Agriculture | Final Report and Policy Document

Perceptions of pest risk and differences in IPM uptake by arable farmers and agronomists in Scotland

November 2022

Pesticide use remains an important tool in managing pest, weed and disease risks to crops and maintaining profitable production. There are several drivers for reducing reliance on pesticides and promoting the uptake of more sustainable practices through integrated pest management (IPM).  By identifying IPM information networks it may be possible to improve the flow of information to farmers by targeting their preferred information sources.  Better informed farmers and agronomists can make better IPM decisions.  Therefore, this project undertook a telephone survey to collect information on currently perceived invertebrate pest and disease threats in Scotland, the level of IPM uptake, and the information sources they relied upon.  

Forestry, Horticulture, Agriculture, Environment | Final Report and Policy Document

Improving knowledge of Xylella fastidiosa vector ecology: modelling vector occurrence and abundance in the wider landscape in Scotland

May 2022

If introduced to the UK, the insect-vectored, bacterial plant pathogen Xylella fastidiosa could be a serious threat to trees and other plants. There is a lack of knowledge about the ecology and distributions of Xylella vectors in Scotland and the potential effects of this on any outbreak of the disease, which this project aimed to address.

Assessment of large-scale biosecurity risks to Scotland

December 2021

PHC commissioned an assessment of large-scale biosecurity risks with a focus on three areas of concern:

  1. non-specialist and online horticulture sales;
  2. landscaping and infrastructure;
  3. planting for environmental benefits.

An additional area was the potential for modelling to support decision making across these areas of concern.  This policy report summaries each report and highlights the key findings and suggested actions.  

Assessment of large-scale plant biosecurity risks to Scotland from non-specialist and online horticultural sales

October 2021

This project focused on an initial exploration of tree and plant biosecurity risks to Scotland arising from large-scale movement of plants via non-specialist (those for which plants are not their primary product type, e.g., supermarkets, DIY and lifestyle stores) and online plant retailers. By better understanding the characteristics of these retailer types, the plant health behaviours they undertake, and the challenges they face, potential avenues were offered for greater engagement and collaboration on biosecurity with this important, but understudied and hard to reach sector.

Assessment of plant biosecurity risks to Scotland from large scale plantings for landscaping and infra-structure projects

October 2021

Planting for large-scale landscaping and infrastructure can typically involve tens of thousands of individual plants, potentially threatening plant health in Scotland due to the biosecurity risks of imports and widespread planting of infested or diseased plants. This project aimed to understand the extent and means to mitigate against such plant biosecurity risks with a focus on mapping the pathways from plant specification through to planting and establishment and highlight different biosecurity awareness for actors, in decision-making and procurement processes.

Assessment of plant biosecurity risks to Scotland from large scale tree plantings for environmental benefits

October 2021

This report features five case studies from across Scotland and examines risks associated with large scale tree planting schemes, levels of awareness around pests and diseases, and how the decisions and actions of those involved can serve to reduce or exacerbate pest and disease related threats and long-term tree health. Each case study was unique in respect to their combination of location, site conditions, ownership, management objectives, species choice, supply chains and management activities. By highlighting best practice and lessons learned, it was hoped to ensure that future planting schemes can be successful and, importantly, reduce the likelihood of pests and diseases being introduced and spread into the wider environment.

The potential of ecological and epidemiological models to inform assessment and mitigation of biosecurity risks arising from large scale planting

October 2021

Large scale planting projects linked to infra-structure such as transport networks and major housing projects or to planting for environmental benefits (e.g., urban greening, woodland restoration) pose high biosecurity risks due to the high number and types of plants involved. This report focusses on whether and how ecological and epidemiological model frameworks can inform assessment and mitigation of biosecurity risks from large scale planting using a combination of literature review and stakeholder engagement.  The project aimed to identify priority steps to develop more useful models and tools for assessing biosecurity risks from planting in the future.

Agriculture | Policy Document

A new IPM Planning Tool for Scottish growers

March 2021

Integrated pest management (IPM) is a holistic approach to managing harmful organisms which maximizes profitability and minimises negative impacts on the environment. IPM aims to reduce reliance on pesticides and promoting IPM is identified as a key action in support of a National Action Plan. To promote IPM practices and improve on-farm uptake, it is essential to understand current uptake levels and better understand what motivates farmers to further adopt IPM. A new integrated pest management planning tool for Scottish growers has been launched, replacing a previous IPM plan. The new plan uses stakeholder derived metrics to value how important different interventions, such as rotations or varieties, are in achieving sustainable reductions in invertebrate pest, weed and disease risk.

Horticulture, Agriculture | Final Report and Policy Document

Monitoring for BMSB in Scotland - Final Report and Policy Summary

March 2021

The increase in global trade brings with it the risk of spread of new pests and diseases into Scotland. Halyomorpha halys, Brown Marmorated Stinkbug (BMSB) is an invasive pest that has already become established in North America and several European countries. The insect aggregates inside houses over winter and can cause problems as an urban nuisance pest in homes as well as being a pest of agriculture. In this project, co-ordinated monitoring for the presence of BMSB was undertaken by teams at SASA and the James Hutton Institute. A reference collection of voucher specimens of common UK stinkbug species was established, including DNA barcoding. A process-oriented climate-based niche model was used by a team at SRUC to determine the areas in Scotland that are suitable for the establishment of BMSB under current and future climates.

Recommendations and suggested 'next steps', including encouraging further surveillance, are detailed in the report and policy summary documents.

Agriculture | Policy Document

PCN Working Group - Final Report

March 2021

Following a Ministerial round table meeting on PCN in June 2020, a working group of over 50 potato industry, government and academic partners was set up (from both Scotland and the wider UK) to identify a clear strategy for dealing with the PCN crisis. Following over 320 person hours of scheduled meetings, plus many days of personal discussions, recommendations for how to combat the growing threat of PCN to the Scottish potato industry have been proposed.

Forestry, Horticulture, Agriculture, Environment | Final Report and Policy Document

PHC2020/09: Economic Impact of Pesticide Withdrawals to Scotland, with Case Studies

March 2021

Chemical forms of plant protection are widely used in Scottish agricultural, horticultural and forestry production plus for amenity and natural environment management purposes.  The availability and use of active substances in pesticides are closely regulated and increasing concern over human health and environmental impacts has led to a greater likelihood that some existing approvals will be withdrawn and/or that approvals for new products will not be granted.  Potential impacts from withdrawal of these pesticides are of policy interest and this summary report builds on the data and results from project PHC2018/15 (Potential impacts arising from pesticide withdrawals to Scotland’s plant health) and uses case studies to understand the likely magnitude and distribution of potential impacts and how they may be mitigated. 

PHC2018/15: Potential Impacts Arising from Pesticide Withdrawals to Scotland’s Plant Health

November 2020

The use of pesticides to manage plant pests and diseases is a key management intervention across plant health sectors, particularly in agriculture, horticulture and commercial forestry production. Pesticide withdrawals through legislation, coupled with resistance development and their impact on plant health, have emerged as key concerns for Scottish plant health stakeholders.  This project quantifies the impacts on Scottish plant health that will arise from pesticide withdrawal scenarios and sets this in the context and time frame of alternative management tools. 

Impact of climate change on the spread of pests and diseases in Scotland

June 2020

This project constructed a modelling framework which combined epidemiological and economic modelling.  The modelling framework was used to study predictions of spread and economic impact of pests which are not currently in the UK, including Xylella fastidiosa, Candidatus Liberibacter solanacearum (Zebra chip) and Ips typographus (Eight toothed Spruce Bark Beetle). 

Impact:  A web/desktop application is available to the PHC and Scottish Government to analyse the effects of climate change on the spread and economic impact of new threats. 

Expansion of PHC Online Plant Health Resources

May 2020

This project has expanded the PHC online Resource Bank for plant health threats to the Natural Environment sector in Scotland to include information sources for the remaining three sectors (Forestry, Agriculture and Horticulture). Information sources for Forestry, Agriculture and Horticulture were compiled and evaluated, and a Knowledge Bank relevant to each sector is now online at the PHC website, creating a comprehensive and unique signposting resource for plant health information with relevance to Scotland.

 

Forestry, Horticulture, Agriculture, Environment | Final Report and Policy Document

The use of mobile technology to enhance plant health monitoring and awareness in Scotland

August 2019

The aim of the project was to review existing websites and smartphone apps currently available and applied in the plant health sector and to assemble a detailed overview covering the following points:

  • What options are available in terms of mobile software applications for plant health?
  • What is their primary purpose?
  • Who is the target audience (growers, plant health professionals, citizen science, …)?
  • Which plant health sectors do they cover?
  • Are they reliable and accurate?
  • Is information submitted to a central database? If so, how is this information used?
  • Could they be used globally, or are they limited to certain geographic regions?
Agriculture | Final Report and Policy Document

Assessing the potential of the psyllid Trioza anthrisci to vector Liberibacter solanacearum (Lso) in Scotland

June 2019

The aim of the project was to assess the distribution and population numbers of the psyllid Trioza anthrisci and it’s potential as a vector of ‘Candidatus Liberibacter solanacearum’ (Lso).  The project has allowed the PHC to better understand the distribution and number of T. anthrisci populations in carrot growing areas to better inform assessment of the risk of disease transmission to crops in Scotland. 

Horticulture, Agriculture | Policy Document

Impact on Scottish crops if the molluscicide metaldehyde is withdrawn

December 2018

This report sets out estimates for the crop loss and value to Scottish crop production should the molluscicide metaldehyde be withdrawn. This would leave ferric phosphate as the only available chemical control option. Short term losses are negligible as the substitution of ferric phosphate carries no additional treatment costs and has equivalent efficacy. Longer term there is some risk should resistance arise to this single site mode of action active, and ferric phosphate (although of lower mammalian toxicity to metaldehyde) has some environmental impacts of its own.