Eco-Epidemiological Uncertainties of Emerging Plant Diseases: The Challenge of Predicting Xylella fastidiosa Dynamics in Novel Environments.

In order to prevent and control the emergence of biosecurity threats such as vector-borne diseases of plants, it is vital to understand drivers of entry, establishment, and spatiotemporal spread, as well as the form, timing, and effectiveness of disease management strategies. An inherent challenge for policy in combatting emerging disease is the uncertainty associated with intervention planning in areas not yet affected, based on models and data from current outbreaks. Following the recent high-profile emergence of the bacterium Xylella fastidiosa in a number of European countries, we review the most pertinent epidemiological uncertainties concerning the dynamics of this bacterium in novel environments. To reduce the considerable ecological and socio-economic impacts of these outbreaks, eco-epidemiological research in a broader range of environmental conditions needs to be conducted and used to inform policy to enhance disease risk assessment, and support successful policy-making decisions. By characterizing infection pathways, we can highlight the uncertainties that surround our knowledge of this disease, drawing attention to how these are amplified when trying to predict and manage outbreaks in currently unaffected locations. To help guide future research and decision-making processes, we invited experts in different fields of plant pathology to identify data to prioritize when developing pest risk assessments. Our analysis revealed that epidemiological uncertainty is mainly driven by the large variety of hosts, vectors, and bacterial strains, leading to a range of different epidemiological characteristics further magnified by novel environmental conditions. These results offer new insights on how eco-epidemiological analyses can enhance understanding of plant disease spread and support management recommendations.[Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license.

On a handshake: business-to-business trust in the biosecurity behaviours of the UK live plant trade.

The movement of plants through the ornamental plant trade presents a major source of risk for the introduction and spread of plant pests and pathogens. To minimise the likelihood of infested or infected plants moving through the value chain, individual businesses can adopt a range of biosecurity practices to prevent introduction on site, as well as detecting and then containing or eradicating any plant pests or pathogens present. However, a major additional source of risk is the arrival of unhealthy plants sourced from a supplier. Using the example of bacterial plant pathogen Xylella fastidiosa which has a large host range and potentially devastating economic and environmental impacts, we highlight the importance of trust when businesses navigate the risks of sourcing plants. Through interviews and a survey with a range of plant businesses, we show (i) how two general types of risk-relational risk associated with suppliers acting in good faith, and performance risk associated with suppliers having the ability to perform as expected-can be applied to the challenge of sourcing healthy plants, (ii) how businesses respond to these risks through behaviours based on trust and control, and (iii) the potential outcomes of trust-based and control-based behaviours in the presence of a hard to detect pathogen such as Xylella fastidiosa. We conclude that trust is a significant component in decision-making in the live plant trade, and as such any behavioural interventions designed to encourage better biosecurity practices in the industry should capitalise on this understanding to strengthen responses and avoid undermining of effort.

Wicked conflict: Using wicked problem thinking for holistic management of conservation conflict.

Conservation conflict is widespread, damaging, and has proved difficult to manage using conventional conservation approaches. Conflicts are often "wicked problems," lacking clear solutions due to divergent values of stakeholders, and being embedded within wickedly complex environments. Drawing on the concept of wicked environmental problems could lead to management strategies better suited to tackling conflict. However, it is unclear whether managers are embracing ideas from the wicked problems concept. There is currently a lack of guidance for applying strategies to tackle particular wicked problems, such as conservation conflict. We explored the suitability of wicked problems-inspired management, using eight contemporary conflict case studies. Conservation conflict was managed predominantly using conventional approaches suited to tackling single objectives in simple environments, rather than balancing competing objectives in complex environments. To deal with different characteristics of wickedness, we recommend that managers develop strategies combining distributed decision-making, diverse opinions, pattern-based predictions, trade-off-based objectives, and reporting of failures. Recent advances in conservation conflict research have focused on improving interactions among stakeholders. We believe that such stakeholder-focused approaches would dovetail with the whole-system focus of a wicked problems framework, allowing conservationists to move toward a holistic strategy for managing conservation conflict.

Games as Tools to Address Conservation Conflicts.

Conservation conflicts represent complex multilayered problems that are challenging to study. We explore the utility of theoretical, experimental, and constructivist approaches to games to help to understand and manage these challenges. We show how these approaches can help to develop theory, understand patterns in conflict, and highlight potentially effective management solutions. The choice of approach should be guided by the research question and by whether the focus is on testing hypotheses, predicting behaviour, or engaging stakeholders. Games provide an exciting opportunity to help to unravel the complexity in conflicts, while researchers need an awareness of the limitations and ethical constraints involved. Given the opportunities, this field will benefit from greater investment and development.