Roger Day

Roger Day
Centre for Agricultural Bioscience International | CABI · International Development

PhD

About

107
Publications
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Introduction
Currently Global Advisor, Plant Health, having previously led CABI's Action on Invasives programme, now merged into CABI's PlantwisePlus programme. Particular interest in prevention, early detection and rapid response to emerging plant health problems.

Publications

Publications (107)
Article
This paper explores the potential role of the private sector, particularly the crop protection industry, in enhancing emergency pest prevention, preparedness and response (EPPPR) in relation to invasive pests. By leveraging their position and knowledge, private companies can contribute significantly to mitigating pest-related risks, enabling sustai...
Article
In the context of risk analysis, horizon scanning activity is a necessary component of any foresight process. This applies also to the specific context of biological invasions, supported and accelerated by climate change and global trade. Today, various institutions and research centres are equipped with a set of tools and methods for early warning...
Article
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Background Fall armyworm ( Spodoptera frugiperda ; FAW), a native pest of the Americas, invaded West Africa about 7 years ago and spread rapidly across the rest of sub-Saharan Africa (SSA) and several countries in Asia and Oceania. Early cross-sectional studies reported that the pest causes severe damage to maize, stimulating widespread use of synt...
Article
In the last 6 years, the fall armyworm (FAW) has spread to the Middle East, Asia and the Pacific, as well as most nations in Africa. This case focuses on sub-Saharan Africa, where more than 300 million people depend on maize, as a staple crop, and the preferred host plant of FAW. Synthetic pesticides against FAW are not always used safely or effect...
Article
Full-text available
The fall armyworm (FAW), Spodoptera frugiperda (JE Smith, 1797), is a serious pest of several crops, particularly maize and other cereals. It has long been known as a pest in the Americas and has invaded most of Africa and parts of the Middle East, Asia, and Australia in the last six years. Its new status as an invasive species causing serious dama...
Article
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We assembled 3,175 geo-tagged occurrences of fall armyworm worldwide and used that data in conjunction with information about the physiological requirements of the pest to spatially assess its global climate suitability. Our analysis indicates that almost the entire African maize crop is grown in areas with climates that support seasonal infestatio...
Article
Deploying maize varieties with fall armyworm (Spodoptera frugiperda [J.E. Smith]; FAW) resistance, desirable product profiles (PPs) and climate resilience is fundamental for food and economic security in sub‐Saharan Africa (SSA). This study reviewed and identified challenges and opportunities for effective and accelerated breeding of demand‐led mai...
Article
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Invasive species have historically been a problem derived from global trade and transport. To aid in the control and management of these species, species distribution models (SDMs) have been used to help predict possible areas of expansion. Our focal organism, the African Armyworm (AAW), has historically been known as an important pest species in A...
Article
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Invasive alien species (IAS) rank among the most significant drivers of species extinction and ecosystem degradation resulting in significant impacts on socio-economic development. The recent exponential spread of IAS in most of Africa is attributed to poor border biosecurity due to porous borders that have failed to prevent initial introductions....
Article
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This paper summarises institutional and policy bottlenecks to IPM in Africa. Agricultural policy in Africa generally prioritises production and productivity above environmental sustainability, so the use of synthetic pesticides for controlling pests is encouraged. Funding for research in IPM is limited, and extension systems struggle to provide the...
Article
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Background Invasive species affect the social, economic and health aspects of many farmers and are known to cause major losses with considerable costs spent on management. Several international agreements recognise the threat caused by invasive species which signatories have an obligation to manage. This paper sets out a framework and method for as...
Article
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Currently, maize (Zea mays L.) production is under threat from climate change, drought, and pests such as fall armyworm (FAW) [Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)]. Since its first detection outside of its native range in 2016, FAW has spread into 76 nations across Africa and Asia adversely affecting maize production and, in...
Article
Full-text available
Currently, maize (Zea mays L.) production is under threat from climate change, drought, and pests such as fall armyworm (FAW) [Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae)]. Since its first detection outside of its native range in 2016, FAW has spread into 76 nations across Africa and Asia adversely affecting maize production and, in...
Article
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BACKGROUND Forecasting the spread of emerging pests is widely requested by pest management agencies in order to prioritise and target efforts. Two widely used approaches are statistical Species Distribution Models (SDMs) and CLIMEX, which uses ecophysiological parameters. Each have strengths and weaknesses. SDMs can incorporate almost any environme...
Preprint
Full-text available
Invasive alien species (IAS) rank among the most significant drivers of species extinction and ecosystem degradation, causing significant impacts on ecosystem services, human well-being and socio-economic development. Recent invasions have spread rapidly in Africa due to porous borders constraining maintenance of border biosecurity. Countries also...
Preprint
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This review summarizes information about various maize landraces, native germplasm, and crop wild relatives possessing FAW resistance traits and about their potential resistance mechanisms, namely antibiosis, antixenosis, and tolerance. Further, a scheme that outlines strategies and approaches for pre-breeding and their introgression into elite var...
Article
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In response to the threat caused by the fall armyworm to African maize farmers, we conducted a series of field release studies with the egg parasitoid Telenomus remus in Ghana. Three releases of ≈15,000 individuals each were conducted in maize plots of 0.5 ha each in the major and minor rainy seasons of 2020, and compared to no-release control plot...
Technical Report
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Huanglongbing (HLB), also known as citrus greening disease, is one of the most devastating pathogens of citrus worldwide and is caused by closely-related species of systemic Candidatus bacteria. Vectored by the Asian citrus psyllid (ACP), Diaphorina citri, the heat-tolerant, Asian form of the disease, Candidatus Liberibacter asiaticus (CLas) is the...
Preprint
Background: Invasive species affect the social, economic and health aspects of many farmers and are known to cause major losses with considerable costs spent on management. Several international agreements recognise the threat caused by invasive species which signatories have an obligation to manage. This paper sets out a framework and method for a...
Technical Report
Full-text available
The South American freshwater apple snail, Pomacea canaliculata (Lamarck) has been introduced and become invasive in many parts of the world, causing significant economic losses in wetland rice cultivation, threatening biodiversity and impacting on human health. The confirmed report in 2020 of this snail species damaging rice crops in Mwea, the mos...
Article
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Since 2016, the invasive fall armyworm (FAW), Spodoptera frugiperda, has been one of the most rapidly spreading and highly devastating maize pests across Africa and Asia. Although several studies have estimated the effect of FAW on maize yield, little is known about its impact on broader welfare outcomes. Using data from smallholder maize‐growing h...
Article
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Following reports of an invasive snail causing crop damage in the expansive Mwea irrigation scheme in Kenya, samples of snails and associated egg masses were collected and sent to CABI laboratories in the UK for molecular identification. DNA barcoding analyses using the cytochrome oxidase subunit I gene gave preliminary identification of the snails...
Article
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The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is a highly polyphagous plant pest that can severely impact yields of several agricultural crops. Understanding the economic impact and management thresholds for FAW across a variety of crop commodities is crucial for effective management. Evaluating the peer-rev...
Article
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Since 2016, the fall armyworm (FAW), Spodoptera frugiperda, has undergone a significant range expansion from its native range in the Americas, to continental Africa, Asia, and in February 2020, mainland Australia. The large dispersal potential of FAW adults, wide host range of immature feeding stages, and unique environmental conditions in its inva...
Article
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The fall armyworm (FAW, Spodoptera frugiperda) has recently spread to many countries in Africa, the Near East, Asia and the Pacific. In sub‐Saharan Africa (SSA), more than 300 million people depend on FAW’s preferred host plant, maize, as a staple crop. Hence, the spread of FAW in SSA has the potential to negatively affect livelihoods and food secu...
Preprint
Following reports of an invasive snail causing crop damage in the expansive Mwea irrigation scheme in Kenya, samples of snails and associated egg masses were collected and sent to CABI laboratories in the UK for molecular identification. DNA barcoding analyses using the cytochrome oxidase subunit I gene confirmed the identity of the snails as Pomac...
Article
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This study quantified crop losses and economic impacts associated with papaya mealybug (Paracoccus marginatus) infestation in Kenya and identified the most important predictors of papaya tree (Carica papaya L.) yield losses through a household survey of 404 farmers. At least 95% male and 88% female respondents correctly identified papaya mealybug....
Article
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Article
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The battle between humans and plant pests is as old as agriculture, but the movement of pests as a consequence of human activities has been exacerbated only recently. International research collaboration is increasingly important to tackle pests causing serious damage to economies.
Article
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Fall armyworm (FAW) is a new invasive pest that is causing devastating effects on maize production and threatening the livelihoods of millions of poor smallholders across sub-Saharan Africa and Asia. Using unique survey data from 2356 maize-growing households in Ghana, Rwanda, Uganda, Zambia and Zimbabwe, we examined how smallholder farmers are fig...
Article
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Background Although Kenya has a relatively high number of registered biopesticide products, little is known about biopesticide use by smallholders. This paper documents farmers' current use and perception of chemical pesticides and biopesticides, their willingness to pay for biopesticides, and the key challenges to biopesticide uptake. Results A s...
Article
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The fall armyworm, Spodoptera frugiperda, a moth originating from the American continent, has recently invaded most African countries, where it is seriously threatening food security as a pest of cereals. The current management methods rely heavily on the use of synthetic insecticides but there is a need for more sustainable control methods, includ...
Article
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Biological control is one of the best options for the sustainable management of the invasive maize pest Spodoptera frugiperda in Africa. However, there is limited knowledge of the efficacy of native natural enemies of S. frugiperda and their potential use in integrated pest management. The endoparasitoid wasp Coccygidium luteum is one of the natura...
Article
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Since its emergence in Africa in 2016, fall armyworm (FAW) has spread rapidly and poses a severe threat to the food security and livelihood of millions of smallholder farmers in the continent. Using survey data from Ghana and Zambia, we examined FAW prevention and control methods implemented by farm households and their impacts on maize output and...
Article
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BACKGROUND This paper documents farmer perceptions and management practices for fall armyworm (Spodoptera frugiderda J.E. Smith), providing a baseline for the development of sustainable pest management strategies. RESULTS 91% of farmers correctly identified fall armyworm, and reported it as the most important maize pest during 2016/2017 cropping s...
Article
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To satisfy a growing demand for food, global agricultural production must increase by 70% by 2050. However, pests and crop diseases put global food supplies at risk. Worldwide, yield losses caused by pests and diseases are estimated to average 21.5% in wheat, 30.0% in rice, 22.6% in maize, 17.2% in potato, and 21.4% in soybean (1); these crops acco...
Technical Report
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Executive summary Background Since its first arrival on the African continent in 2008, the tomato leafminer, Tuta absoluta, remains the most important biotic constraint to tomato production in North and sub-Saharan Africa. Subsequently, several research efforts have been undertaken to understand the bio-ecology of Tuta absoluta and to develop integ...
Article
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This is an opinion paper to the perspective paper “The spread of the Fall Army Worm Spodoptera frugiperda in Africa—what should be done next?” from the “Section Plant Protection in the Tropics and Subtropics” at the 61st German Congress of Plant Protection, held at the University of Hohenheim, Germany, on 11 September 2018. It highlights the best a...
Article
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Fall armyworm, Spodopterafrugiperda , is a crop pest native to the Americas, which has invaded and spread throughout sub-Saharan Africa within two years. Recent estimates of 20–50% maize yield loss in Africa suggest severe impact on livelihoods. Fall armyworm is still infilling its potential range in Africa and could spread to other continents. In...
Technical Report
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This Evidence Note provides new evidence on the distribution and impact of fall armyworm in Africa, summarises research and development on control methods, and makes recommendations for sustainable management of the pest.
Article
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The fall armyworm (FAW, Spodoptera frugiperda) originates from the tropical and sub‐tropical regions of the Americas. Recently it was reported for the first time in Africa and has since spread rapidly across more than 30 countries in the continent. Chemical pesticides are being promoted and used for FAW management, but where application practices a...
Preprint
Full-text available
Fall armyworm, Spodoptera frugiperda , is a crop pest native to the Americas, which has invaded and spread throughout sub-Saharan Africa within two years. Recent estimates of 20-50% maize yield loss in Africa suggest severe damage to livelihoods. Fall armyworm is still infilling its potential range in Africa, and could spread to other continents. I...
Article
Full-text available
Abstract EFSA was asked for a partial risk assessment of Spodoptera frugiperda for the territory of the EU focussing on the main pathways for entry, factors affecting establishment, risk reduction options and pest management. As a polyphagous pest, five commodity pathways were examined in detail. Aggregating across these and other pathways, we esti...
Article
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The appearance of Fall Armyworm (FAW) (Spodoptera frugiperda) in Africa has caused much consternation: “The hungry caterpillar threatening a global food crisis”, according to a headline in the Guardian newspaper. The UK Department for International Development (DFID) commissioned CABI to compile an evidence note, which was published by CABI in Sept...
Chapter
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This proceedings contains papers dealing with issues affecting biological control, particularly pertaining to the use of parasitoids and predators as biological control agents. This includes all approaches to biological control: conservation, augmentation, and importation of natural enemy species for the control of arthropod targets, as well as oth...
Conference Paper
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Day, R.K., Cock, M.J.W. and Kuhlman, U. (2017) Success and impact in classical biological control; some examples from developing countries. [Extended abstract]. In: Mason, P.G., Gillespie, D.R. and Vincent, C. (eds) Proceedings of the 5th International Symposium on Biological Control of Arthropods, Langkawi, Malaysia, September 11-15, 2017. CABI, W...
Article
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Despite growth in Rwanda's agricultural production ability, with food crops representing 33% of the National GDP and 80% of the population reliant on agriculture, food supply remains fragile. A factor which has significant impact on productivity is soil pests, whose effects filter through the whole value chain. Poor yields result in demand that exc...
Article
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We differentiate between the success of a classical biological control programme and its impact; the former addressing the completed implementation of the steps of a biological control programme, and the anticipated reduction of the target pest, and the latter addressing the societal and environmental benefits of control of the target pest. We prov...
Article
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Up to 80 % of global commodity production comes from smallholdings of less than 0.5 ha. Yet commodity crops may be a substantial proportion of a country’s exports, and feed into global supply networks. Pest risks thus have consequences at local, national and global levels. We consider three categories of risk in global commodity networks: introduct...
Research
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Key messages • Africa's food and agricultural exports must comply with the importing countries' sanitary and phytosanitary (SPS) requirements. Inability to comply would mean lost market opportunities and lost revenue. • SPS compliance involves action by farmers and others in the value chain, as well as government and regulatory bodies. Private and...
Research
Full-text available
Key messages • Africa's food and agricultural exports must comply with the importing countries' sanitary and phytosanitary (SPS) requirements. Inability to comply would mean lost market opportunities and lost revenue. • SPS compliance involves action by farmers and others in the value chain, as well as government and regulatory bodies. Private and...
Conference Paper
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Agricultural extension has been undergoing major changes. Changing policies, declining public funding, new thinking and approaches, climate change and other environmental factors pose major challenges to public sector extension services. Pre-packaged, crop and region-biased extension approaches often failed to help remote and resource poor farmers...
Article
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Many development interventions have failed to generate the desired impact among African resource-poor farmers for reasons including the centralised and top-down approach, lack of active community participation, and over-reliance on external information and technology delivery strategies and channels. The migrant African armyworm, Spodoptera exempta...
Article
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Leptocybe invasa, an invasive gall-inducing wasp of Australian origin, recently emerged as a serious eucalyptus pest of global importance. We examined the spatial and temporal variations in L. invasa adult populations and evaluated eucalyptus gemplasms for infestations by the wasp in Uganda and Kenya. There were significant differences in L. invasa...
Article
Very little is known about Leptocybe invasa Fisher & LaSalle, a new fast-spreading alien pest infesting Eucalyptus in several countries. This study examined L. invasa infestation on Eucalyptus germplasms in different agroecological zones of Uganda. The incidence and severity of the pest infestation were higher in hotter and drier agroecological zon...
Article
Cupressus lusitanica seedlings from open-pollinated seeds of 18 families were inoculated with day-old first instar Cinara cupressi. Aphid survival was used to determine the genetic basis and inheritance of resistance to the insect. There was marked variation in aphid survival both between and within families. An individual-tree narrow-sense heritab...