Climate change effects on Black Sigatoka disease of banana

This is the final version. Available on open access from the Royal Society via the DOI in this record Data accessibility: JRA55 data are available from the Research Data Archive of the National Center for Atmospheric Research at https://rda.ucar.edu. SPAM crop distribution data area available from http://mapspam.info.Climate change has significantly altered species distributions in the wild and has the potential to affect the interactions between pests and diseases and their human, animal and plant hosts. While several studies have projected changes in disease distributions in the future, responses to historical climate change are poorly understood. Such analyses are required to dissect the relative contributions of climate change, host availability and dispersal to the emergence of pests and diseases. Here, we model the influence of climate change on the most damaging disease of a major tropical food plant, Black Sigatoka disease of banana. Black Sigatoka emerged from Asia in the late twentieth Century and has recently completed its invasion of Latin American and Caribbean banana-growing areas. We parametrize an infection model with published experimental data and drive the model with hourly microclimate data from a global climate reanalysis dataset. We define infection risk as the sum of the number of modelled hourly spore cohorts that infect a leaf over a time interval. The model shows that infection risk has increased by a median of 44.2% across banana-growing areas of Latin America and the Caribbean since the 1960s, due to increasing canopy wetness and improving temperature conditions for the pathogen. Thus, while increasing banana production and global trade have probably facilitated Black Sigatoka establishment and spread, climate change has made the region increasingly conducive for plant infection. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'. This issue is linked with the subsequent theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'.Biotechnology & Biological Sciences Research Council (BBSRC)European Union Horizon 202

Tropical protected areas reduced deforestation carbon emissions by one third from 2000-2012

This is the final version. Available on open access from Springer Nature via the DOI in this recordTropical deforestation is responsible for around one tenth of total anthropogenic carbon emissions, and tropical protected areas (PAs) that reduce deforestation can therefore play an important role in mitigating climate change and protecting biodiversity and ecosystem services. While the effectiveness of PAs in reducing deforestation has been estimated, the impact on global carbon emissions remains unquantified. Here we show that tropical PAs overall reduced deforestation carbon emissions by 4.88 Pg, or around 29%, between 2000 and 2012, when compared to expected rates of deforestation controlling for spatial variation in deforestation pressure. The largest contribution was from the tropical Americas (368.8 GgC y-1), followed by Asia (25.0 GgC y-1) and Africa (12.7 GgC y-1). Variation in PA effectiveness is largely driven by local factors affecting individual PAs, rather than designations assigned by governments

The long road to a sustainable banana trade

This is the final version. Available from Wiley via the DOI in this record. DATA AVAILABILITY STATEMENT: The UK Government consumer price inflation (CPI) time series data (dataset ID MM23) are available online (https://www.ons.gov.uk/ economy/inflationandpriceindices/datasets/consumerpriceindices).Societal Impact Statement: Bananas are the world's most popular dessert fruit and a staple starch crop for millions in low- and middle-income countries. The banana export trade that supplies North America, Europe, and other wealthy nations has a history fraught with exploitation and conflict. The price of cheap bananas has been environmental degradation, violence, and poverty. Only recently have efforts to address the power imbalances in this trade been made. Voluntary certification schemes aim to address multiple sustainability issues, while research into biological control, accelerated plant breeding, and efficient irrigation will help prepare the industry for emerging threats from pests, diseases, and climate change. Summary: Bananas are the world's favorite dessert fruit, a staple starch crop for millions, and an important source of income for producers across the tropics and subtropics. Bananas evolved and diversified as giant perennial herbs of open habitats within the humid forests of Southeast Asia and West Oceania and were domesticated around 7000 years BP through a series of hybridization events. This review considers the journey from rainforest riversides to intensively managed monoculture plantations, focussing on the Cavendish banana that comprises nearly the entire global export trade. Climate change increasingly threatens economic sustainability in several major producer regions, requiring responses such as efficient irrigation systems to maintain productivity and water security. Pests and diseases are spreading globally and have severe direct impacts on production as well as indirect impacts via harm to ecological and human health caused by pesticides. New pest and disease management methods employing biological controls and enhancing soil health and new plant breeding techniques must be developed and implemented. The banana production and trade system has been characterized by power imbalances between international firms that own plantations and supply the market and the local agricultural workers who cultivate and harvest the fruit. Voluntary certification schemes have been developed to address the numerous environmental, social, and economic sustainability issues faced by the industry. There are indications, from research on biological disease control to new deals on wages and benefits for banana workers, that change is slowly coming to the global banana trade.Biotechnology and Biological Sciences Research CouncilEuropean Union’s Horizon 202

Modelling coffee leaf rust risk in Colombia with climate reanalysis data.

PublishedJournal ArticleThis is the final version of the article. Available from Royal Society via the DOI in this record.Many fungal plant diseases are strongly controlled by weather, and global climate change is thus likely to have affected fungal pathogen distributions and impacts. Modelling the response of plant diseases to climate change is hampered by the difficulty of estimating pathogen-relevant microclimatic variables from standard meteorological data. The availability of increasingly sophisticated high-resolution climate reanalyses may help overcome this challenge. We illustrate the use of climate reanalyses by testing the hypothesis that climate change increased the likelihood of the 2008-2011 outbreak of Coffee Leaf Rust (CLR, Hemileia vastatrix) in Colombia. We develop a model of germination and infection risk, and drive this model using estimates of leaf wetness duration and canopy temperature from the Japanese 55-Year Reanalysis (JRA-55). We model germination and infection as Weibull functions with different temperature optima, based upon existing experimental data. We find no evidence for an overall trend in disease risk in coffee-growing regions of Colombia from 1990 to 2015, therefore, we reject the climate change hypothesis. There was a significant elevation in predicted CLR infection risk from 2008 to 2011 compared with other years. JRA-55 data suggest a decrease in canopy surface water after 2008, which may have helped terminate the outbreak. The spatial resolution and accuracy of climate reanalyses are continually improving, increasing their utility for biological modelling. Confronting disease models with data requires not only accurate climate data, but also disease observations at high spatio-temporal resolution. Investment in monitoring, storage and accessibility of plant disease observation data are needed to match the quality of the climate data now available.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'.We thank Gerry and Clemencia Brown for their sponsorship of A.D. S.G. acknowledges support from the University of Utrecht

The global spread of crop pests and pathogens

AcceptedArticle in PressCopyright © 2014 The Authors. Global Ecology and Biogeography published by John Wiley & Sons Ltd.Aim: To describe the patterns and trends in the spread of crop pests and pathogens around the world, and determine the socioeconomic, environmental and biological factors underlying the rate and degree of redistribution of crop-destroying organisms. Location: Global. Methods: Current country- and state-level distributions of 1901 pests and pathogens and historical observation dates for 424 species were compared with potential distributions based upon distributions of host crops. The degree of 'saturation', i.e. the fraction of the potential distribution occupied, was related to pest type, host range, crop production, climate and socioeconomic variables using linear models. Results: More than one-tenth of all pests have reached more than half the countries that grow their hosts. If current trends continue, many important crop-producing countries will be fully saturated with pests by the middle of the century. While dispersal increases with host range overall, fungi have the narrowest host range but are the most widely dispersed group. The global dispersal of some pests has been rapid, but pest assemblages remain strongly regionalized and follow the distributions of their hosts. Pest assemblages are significantly correlated with socioeconomics, climate and latitude. Tropical staple crops, with restricted latitudinal ranges, tend to be more saturated with pests and pathogens than temperate staples with broad latitudinal ranges. We list the pests likely to be the most invasive in coming years. Main conclusions: Despite ongoing dispersal of crop pests and pathogens, the degree of biotic homogenization of the globe remains moderate and regionally constrained, but is growing. Fungal pathogens lead the global invasion of agriculture, despite their more restricted host range. Climate change is likely to influence future distributions. Improved surveillance would reveal greater levels of invasion, particularly in developing countries. © 2014 John Wiley & Sons Ltd.BBSR

Weather does influence fungal and oomycete crop disease outbreaks, but ProMED-mail reports don't prove it

This is the final version. Available on open access from Wiley via the DOI in this recordA comment on Romero et al. (2021) ‘Humidity and high temperature are important for predicting fungal disease outbreaks worldwid

Economic and physical determinants of the global distributions of crop pests and pathogens.

© 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.Crop pests and pathogens pose a significant and growing threat to food security, but their geographical distributions are poorly understood. We present a global analysis of pest and pathogen distributions, to determine the roles of socioeconomic and biophysical factors in determining pest diversity, controlling for variation in observational capacity among countries. Known distributions of 1901 pests and pathogens were obtained from CABI. Linear models were used to partition the variation in pest species per country amongst predictors. Reported pest numbers increased with per capita gross domestic product (GDP), research expenditure and research capacity, and the influence of economics was greater in micro-organisms than in arthropods. Total crop production and crop diversity were the strongest physical predictors of pest numbers per country, but trade and tourism were insignificant once other factors were controlled. Islands reported more pests than mainland countries, but no latitudinal gradient in species richness was evident. Country wealth is likely to be a strong indicator of observational capacity, not just trade flow, as has been interpreted in invasive species studies. If every country had US levels of per capita GDP, then 205 ± 9 additional pests per country would be reported, suggesting that enhanced investment in pest observations will reveal the hidden threat of crop pests and pathogens.BBSR

Specialists, generalists and the shape of the ecological niche in fungi

This is the final version. Available on open access from Wiley via the DOI in this recordData availability: Data used in the publication are openly available from the publications cited as sources in the manuscript.Biotechnology and Biological Sciences Research Council (BBSRC

A new mechanistic model of weather-dependent Septoria tritici blotch disease risk

This is the final version. Available on open access from the Royal Society via the DOI in this record.Data accessibility: All data and code associated with this work are available as supplementary material or on Github (https://github.com/thomaschaloner/A_new_mechanistic_model_of_weather-dependent_Septoria_tritici_blotch_disease_risk), respectively.We present a new mechanistic model for predicting Septoria tritici blotch (STB) disease, parameterized with experimentally derived data for temperature- and wetness-dependent germination, growth and death of the causal agent, Zymoseptoria tritici. The output of this model (A) was compared with observed disease data for UK wheat over the period 2002-2016. In addition, we compared the output of a second model (B), in which experimentally derived parameters were replaced by a modified version of a published Z. tritici thermal performance equation, with the same observed disease data. Neither model predicted observed annual disease, but model A was able to differentiate UK regions with differing average disease risks over the entire period. The greatest limitations of both models are: broad spatial resolution of the climate data, and lack of host parameters. Model B is further limited by its lack of explicitly defined pathogen death, leading to a cumulative overestimation of disease over the course of the growing season. Comparison of models A and B demonstrates the importance of accounting for the temperature-dependency of pathogen processes important in the initiation and progression of disease. However, effective modelling of STB will probably require similar experimentally derived parameters for host and environmental factors, completing the disease triangle. This article is part of the theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: approaches and important themes'. This issue is linked with the subsequent theme issue 'Modelling infectious disease outbreaks in humans, animals and plants: epidemic forecasting and control'

Stable forest carbon stocks support current assumption of biogenic carbon neutrality in the case of European-manufactured beverage cartons

This is the final version. Available on open access from Springer Verlag via the DOI in this recordPurpose: Life cycle assessments (LCAs) of forest-based products, such as beverage cartons, generally demonstrate lower greenhouse gas emissions than fossil fuel-based alternatives and often contain the implicit assumption that removal of carbon dioxide (CO2) by a growing forest and emission of CO2at the end of a product’s life cancel each other out such that the net emission is zero. This study aims to test the validity of this assumption of biogenic CO2neutrality in relation to beverage cartons by examining whether carbon stocks of the source forests are stable. The fact that over 95 % of the cartonboard used in their manufacture is sourced from the boreal forests of Sweden and Finland provides a scenario with a straightforward relationship between forest and product thus avoiding issues surrounding the complexities of global supply chains. Methods: The reviewed LCAs conclude that beverage cartons have lower greenhouse gas emissions than alternatives, although non-forest-derived components such as plastic caps and aluminium laminate often contribute disproportionately to those emissions. We discuss issues surrounding the assumption of biogenic CO2neutrality and explore the factors that influence carbon stocks in boreal forests that supply much of the raw material for beverage cartons. Results and discussion: An analysis of published rates of carbon sequestration in the managed forests of Finland and Sweden reveals that forest carbon is stable under current harvest rates. This lends support to the assumption of biogenic CO2neutrality in the case of beverage cartons produced from these forests. We conclude that greenhouse gas emissions would not change if an LCA included forest carbon. However, future forest dynamics and thus carbon stocks are predicted to alter in response to climate change, for example, which will have knock on effects for greenhouse gas emissions from packaging derived from forests. Conclusions: This review combines current thinking on inclusion of forest carbon in LCAs with an analysis of issues that will influence carbon stocks in managed forests. Although current assumptions of biogenic CO2neutrality are valid in the case of European-manufactured beverage cartons, we argue that this assumption needs to be explicitly addressed in LCAs. While there is no accepted methodology for integrating biogenic forest carbon uptake into LCA, our assessment of current trends in forest carbon stocks allows for assumptions of biogenic CO2neutrality to be tested, although our approach may not be practical for more complex supply chains.This paper is based on research funded by The Alliance for Beverage Cartons and the Environment (ACE) UK and the Earthwatch Institute