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Journal article
Chemistry of floral rewards: intra- and interspecific variability of nectar and pollen secondary metabolites across taxa
Floral chemistry mediates plant interactions with pollinators, pathogens, and herbivores, with major consequences for fitness of both plants and flower visitors. The outcome of such interactions often depends on compound dose and chemical context. However, chemical diversity and intraspecific variation of nectar and pollen secondary chemistry are known for very... -
Journal article
From plant fungi to bee parasites: mycorrhizae and soil nutrients shape floral chemistry and bee pathogens
Bee populations have experienced declines in recent years, due in part to increased disease incidence. Multiple factors influence bee-pathogen interactions, including nectar and pollen quality and secondary metabolites. However, we lack an understanding of how plant interactions with their environment shape bee diet quality. We examined how plant interactions with... -
Journal article
Mechanisms in mutualisms: a chemically mediated thrips pollination strategy in common elder
The concept of flower-feeding thrips as pollinating insects in temperate regions is rarely considered as they are more frequently regarded to be destructive florivores feeding on pollen and surrounding plant tissue. Combining laboratory and field-based studies we examined interactions between Sambucus nigra (elderflower) and Thrips major within their native range... -
Journal article
Rosmarinic acid in Canna generalis activates the medial deterrent chemosensory neurone and deters feeding in the tobacco hornworm Manduca sexta
For all but a very few highly specialized insect feeders, Canna generalis L. (Cannaceae) is unacceptable as a food plant and is a highly potent feeding deterrent for the tobacco hornworm Manduca sexta Johan. (Lepidoptera). The present study describes the isolation of an active deterrent compound, rosmarinic acid (RA) from...Simmonds, Monique S.J. ; Stevenson, Philip C. ; Hanson, Frank E.
sensory coding, feeding behaviour, phagodeterrents, phytochemistry, Lepidoptera, and insect neurophysiology
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Data paper
Secondary metabolites from nectar and pollen: a resource for ecological and evolutionary studies
Floral chemistry mediates plant interactions with herbivores, pathogens, and pollinators. The chemistry of floral nectar and pollen, the primary food rewards for pollinators, can affect both plant reproduction and pollinator health. Although the existence and functional significance of nectar and pollen secondary metabolites has long been known, comprehensive quantitative characterizations...Palmer-Young, Evan ; Farrell, Iain ; Adler, Lynn ; Milano, Nelson ; Egan, Paul …
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Journal article
The climatic challenge: Which plants will people use in the next century?
More than 31,000 useful plant species have been documented to fulfil needs and services for humans or the animals and environment we depend on. Despite this diversity, humans currently satisfy most requirements with surprisingly few plant species; for example, just three crops – rice, wheat and maize – comprise more... -
Journal article
For antagonists and mutualists: the paradox of insect toxic secondary metabolites in nectar and pollen
The plant kingdom produces an extraordinary diversity of secondary metabolites and the majority of the literature supports a defensive ecological role for them, particularly against invertebrate herbivores (antagonists). Plants also produce secondary compounds in floral nectar and pollen and these are often similar to those produced for defense against invertebrates...Stevenson, Philip C.
Bombus, Bee pathogens, Nicotine, Caffeine, Pollinator specialization, Nectar chemicals, and Crithidia bombi
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Journal article
Flagellum Removal by a Nectar Metabolite Inhibits Infectivity of a Bumblebee Parasite
Plant phytochemicals can act as natural ‘‘medicines’’ for animals against parasites [1–3]. Some nectar metabolites, for example, reduce parasite infections in bees [4–7]. Declining plant diversity through anthropogenic landscape change [8–11] could reduce the availability of medicinal nectar plants for pollinators, exacerbating their decline [12]. Existing studies are, however, limited... -
Journal article
Characterization of Hymenopteran Parasitoids of Aphis fabae in an African Smallholder Bean Farming System through Sequencing of COI ‘Mini-Barcodes’
Parasitoids are among the most frequently reported natural enemies of insect pests, particularly aphids. The efficacy of parasitoids as biocontrol agents is influenced by biotic and abiotic factors. For example, hyperparasitoids can reduce the abundance of the primary parasitoids as well as modify their behavior. A field study was conducted... -
Journal article
Field Margin Vegetation in Tropical African Bean Systems Harbours Diverse Natural Enemies for Biological Pest Control in Adjacent Crops
Non-crop vegetation around farmland can be valuable habitats for enhancing ecosystem services but little is known of the importance of field margins in supporting natural enemies of insect pests in tropical agriculture. This study was conducted in smallholder bean fields in three elevation zones to assess the importance of field...Mkenda, Prisila A. ; Ndakidemi, Patrick A. ; Stevenson, Philip C. ; Arnold, Sarah E. J. ; Belmain, Steven R. …
ecosystem service, parasitoids, pest regulation, predators, and non-crop vegetation
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Journal article
Multiple ecosystem services from field margin vegetation for ecological sustainability in agriculture: scientific evidence and knowledge gaps
Background Field margin and non-crop vegetation in agricultural systems are potential ecosystem services providers because they offer semi-natural habitats for both below and above ground animal groups such as soil organisms, small mammals, birds and arthropods that are service supplying units. They are considered as a target area for... -
Journal article
A comparison of coffee floral traits under two different agricultural practices
Floral traits and rewards are important in mediating interactions between plants and pollinators. Agricultural management practices can affect abiotic factors known to influence floral traits; however, our understanding of the links between agricultural practices and floral trait expression is still poorly understood. Variation in floral morphological, nectar, and pollen traits...Prado, Sara Guiti ; Collazo, Jaime A. ; Stevenson, Philip C. ; Irwin, Rebecca E.
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Journal article
Floral Odors and the Interaction between Pollinating Ceratopogonid Midges and Cacao
Most plant species depend upon insect pollination services, including many cash and subsistence crops. Plants compete to attract those insects using visual cues and floral odor which pollinators associate with a reward. The cacao tree, Theobroma cacao, has a highly specialized floral morphology permitting pollination primarily by Ceratopogonid midges. However,... -
Journal article
Phytochemical Analysis of Tephrosia vogelii across East Africa Reveals Three Chemotypes that Influence Its Use as a Pesticidal Plant
Tephrosia vogelii is a plant species chemically characterized by the presence of entomotoxic rotenoids and used widely across Africa as a botanical pesticide. Phytochemical analysis was conducted to establish the presence and abundance of the bioactive principles in this species across three countries in East Africa: Tanzania, Kenya, and Malawi....Mkindi, Angela G. ; Tembo, Yolice ; Mbega, Ernest R. ; Medvecky, Beth ; Kendal-Smith, Amy …
deguelin, chemotype 3, botanical insecticides, spatial-temporal variation, and rotenoids
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Journal article
Bioactivity of Common Pesticidal Plants on Fall Armyworm Larvae (Spodoptera frugiperda)
The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae) is a recent invasive pest species that has successfully established across sub-Saharan Africa where it continues to disrupt agriculture, particularly smallholder cereal production. Management of FAW in its native range in the Americas has led to the development of resistance to many... -
Journal article
Knowledge gaps among smallholder farmers hinder adoption of conservation biological control
Conservation biological control uses habitat management to enhance the survival and impact of arthropod natural enemies for pest control. Its advantages are that it relies on native or established invertebrate populations that are adapted to local agricultural ecosystems and conditions. We surveyed 300 farmers in three agro-ecological zones of Kilimanjaro... -
Journal article
Extracts of Common Pesticidal Plants Increase Plant Growth and Yield in Common Bean Plants
Common bean (Phaseolus vulgaris) is an important food and cash crop in many countries. Bean crop yields in sub-Saharan Africa are on average 50% lower than the global average, which is largely due to severe problems with pests and diseases as well as poor soil fertility exacerbated by low-input smallholder...Mkindi, Angela G. ; Tembo, Yolice L.B. ; Mbega, Ernest R. ; Kendal-Smith, Amy ; Farrell, Iain W. …
tryptophan, phenylalanine, rutin, botanicals, induced systemic response, and foliar fertiliser
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Journal article
Additive Effect of Botanical Insecticide and Entomopathogenic Fungi on Pest Mortality and the Behavioral Response of Its Natural Enemy
Sustainable agricultural intensification employs alternatives to synthetic insecticides for pest management, but these are not always a direct replacement. Botanical insecticides, for example, have rapid knockdown but are highly labile and while biological pesticides are more persistent, they are slow acting. To mitigate these shortcomings, we combined the entomopathogenic fungus... -
Journal article
Opportunities and Scope for Botanical Extracts and Products for the Management of Fall Armyworm (Spodoptera frugiperda) for Smallholders in Africa.
Fall Armyworm (FAW) (Spodoptera frugiperda) is a polyphagous and highly destructive pest of many crops. It was recently introduced into Africa and now represents a serious threat to food security, particularly because of yield losses in maize, which is the staple food for the majority of small-scale farmers in Africa....Rioba, Naomi B. ; Stevenson, Philip C.
Biopesticides, Botanicals, Fall Armyworm, Prospects, Zea mays, Corn, Pests, Africa, Spodoptera frugiperda, and Insects
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Journal article
Age-related pharmacodynamics in a bumblebee–microsporidian system mirror similar patterns in vertebrates
Immune systems provide a key defence against diseases. However, they are not a panacea and so both vertebrates and invertebrates co-opt naturally occurring bioactive compounds to treat themselves against parasites and pathogens. In vertebrates, this co-option is complex, with pharmacodynamics leading to differential effects of treatment at different life stages,...Folly, Arran J. ; Stevenson, Philip C. ; Brown, Mark J. F.
Bombus terrestris, pollinator health, medication, Trifolium pratense, phytochemicals, and Nosema bombi