The Experts below are selected from a list of 28911 Experts worldwide ranked by ideXlab platform
Åke Brännström - One of the best experts on this subject based on the ideXlab platform.
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Pareto-efficient Biological Pest Control enable high efficacy at small costs
Ecological Modelling, 2017Co-Authors: Niklas L. P. Lundström, Hong Zhang, Åke BrännströmAbstract:Biological Pest Control is increasingly used in agriculture as an alternative to traditional chemical Pest Control. In many cases, this involves a one-off or periodic release of naturally occurring ...
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Pareto-efficient Biological Pest Control enable high efficacy at small costs
arXiv: Populations and Evolution, 2016Co-Authors: Niklas L. P. Lundström, Hong Zhang, Åke BrännströmAbstract:Biological Pest Control is increasingly used in agriculture as a an alternative to traditional chemical Pest Control. In many cases, this involves a one-off or periodic release of naturally occurring and/or genetically modified enemies such as predators, parasitoids, or pathogens. As the interaction between these enemies and the Pest is complex and the production of natural enemies potentially expensive, it is not surprising that both the efficacy and economic viability of Biological Pest Control are debated. Here, we investigate the performance of very simple Control strategies. In particular, we show how Pareto-efficient one-off or periodic release strategies, that optimally trade off between efficacy and economic viability, can be devised and used to enable high efficacy at small economic costs. We demonstrate our method on a Pest-pathogen-crop model with a tunable immigration rate of Pests. By analyzing this model, we demonstrate that simple Pareto-efficient one-off and periodic release strategies are efficacious and simultaneously have profits that are close to the theoretical maximum obtained by strategies optimizing only the profit. When the immigration rate of Pests is low to intermediate, one-off Control strategies are sufficient, and when the immigration of Pests is high, periodic release strategies are preferable. The methods presented here can be extended to more complex scenarios and be used to identify promising Biological Pest Control strategies in many circumstances.
Teja Tscharntke - One of the best experts on this subject based on the ideXlab platform.
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when natural habitat fails to enhance Biological Pest Control five hypotheses
Biological Conservation, 2016Co-Authors: Teja Tscharntke, Mattias Jonsson, Daniel S Karp, Rebecca Chaplinkramer, Peter Batary, Fabrice Declerck, Claudio Gratton, Lauren Hunt, Anthony R Ives, Ashley E LarsenAbstract:Abstract Ecologists and farmers often have contrasting perceptions about the value of natural habitat in agricultural production landscapes, which so far has been little acknowledged in ecology and conservation. Ecologists and conservationists often appreciate the contribution of natural habitat to biodiversity and potential ecosystem services such as Biological Pest Control, whereas many farmers see habitat remnants as a waste of cropland or source of Pests. While natural habitat has been shown to increase Pest Control in many systems, we here identify five hypotheses for when and why natural habitat can fail to support Biological Pest Control, and illustrate each with case studies from the literature: (1) Pest populations have no effective natural enemies in the region, (2) natural habitat is a greater source of Pests than natural enemies, (3) crops provide more resources for natural enemies than does natural habitat, (4) natural habitat is insufficient in amount, proximity, composition, or configuration to provide large enough enemy populations needed for Pest Control, and (5) agricultural practices counteract enemy establishment and bioControl provided by natural habitat. In conclusion, we show that the relative importance of natural habitat for bioControl can vary dramatically depending on type of crop, Pest, predator, land management, and landscape structure. This variation needs to be considered when designing measures aimed at enhancing bioControl services through restoring or maintaining natural habitat.
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economic trade offs between carbon sequestration timber production and crop pollination in tropical forested landscapes
Ecological Complexity, 2010Co-Authors: Roland Olschewski, Alexandramaria Klein, Teja TscharntkeAbstract:The Millennium Ecosystem Assessment distinguishes between supporting, regulating, provisioning, and cultural ecosystem services. We focus on three services, namely the provision of timber, the regulation of atmospheric carbon dioxide, and the supporting service of bee pollination for coffee production. Possible trade-offs between the different ecosystem services might result in a reduced attractiveness of afforestation projects when taking pollination services into account. We found that economic losses due to a limited reduction of tree density of a Cordia alliodora plantation can be overcompensated by generating pollination services to adjacent coffee agroforestry systems. Thus, for moderate silvicultural interventions such trade-offs do not necessarily occur. Including additional ecosystem services such as Biological Pest Control or seed dispersal, which are also associated with the enhanced functional biodiversity in less dense tree plantations, might further emphasize the hump-shaped relationship between tree density and forest revenues.
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relative importance of predators and parasitoids for cereal aphid Control
Proceedings of The Royal Society B: Biological Sciences, 2003Co-Authors: Martin Schmidt, Carsten Thies, Andreas Lauer, Tobias Purtauf, Matthias Schaefer, Teja TscharntkeAbstract:Field experiments with manipulations of natural enemies of plant-feeding insects may show how a diverse enemy group ensures an important ecosystem function such as naturally occurring Biological Pest Control. We studied cereal aphid populations in winter wheat under experimentally reduced densities of: (i) ground-dwelling generalist predators (mostly spiders, carabid and staphylinid beetles); (ii) flying predators (coccinellid beetles, syrphid flies, gall midges, etc.) and parasitoids (aphidiid wasps), and a combination of (i) and (ii), compared with open Controls. Aphid populations were 18% higher at reduced densities of ground-dwelling predators, 70% higher when flying predators and parasitoids were removed, and 172% higher on the removal of both enemy groups. Parasitoid wasps probably had the strongest effect, as flying predators occurred only in negligible densities. The great importance of parasitism is a new finding for aphid Control in cereal fields. In conclusion, a more detailed knowledge of the mechanisms of natural Pest Control would help to develop environmentally sound crop management with reduced Pesticide applications.
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Landscape structure and Biological Control in agroecosystems
Science, 1999Co-Authors: Carsten Thies, Teja TscharntkeAbstract:Biological Pest Control has primarily relied on local improvements in populations of natural enemies, but landscape structure may also be important. This is shown here with experiments at different spatial scales using the rape pollen beetle (Meligethes aeneus), an important Pest on oilseed rape (Brassica napus). The presence of old field margin strips along rape fields was associated with increased mortality of pollen beetles resulting from parasitism and adjacent, large, old fallow habitats had an even greater effect. In structurally complex landscapes, parasitism was higher and crop damage was lower than in simple landscapes with a high percentage of agricultural use.
Geoff M Gurr - One of the best experts on this subject based on the ideXlab platform.
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field margin vegetation in tropical african bean systems harbours diverse natural enemies for Biological Pest Control in adjacent crops
Sustainability, 2019Co-Authors: Prisila A Mkenda, Patrick A Ndakidemi, Philip C Stevenson, Sarah E J Arnold, Steven R Belmain, Maneno Chidege, Geoff M GurrAbstract: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 margin vegetation to natural enemy populations and movement to the bean crop for Biological Pest Control. The Pests and natural enemies were assessed using different coloured water pan traps (to ensure the capture of insects with different colour preferences) and the interactions of the two arthropod groups with the margin vegetation and their movement to the bean crop were monitored using fluorescent dye. Sentinel plants were used to assess predation and parasitism levels. A total of 5003 natural enemies were captured, more in the field margin than within the bean field for low and mid elevation zones, while in the high elevation zone, they were more abundant within the bean field. Pests were more abundant in the crop than margins for all the elevation zones. The use of a dye applied to margin vegetation demonstrated that common natural enemy taxa moved to the crop during the days after dye application. The proportion of dye-marked natural enemies (showing their origin to be margin vegetation) sampled from the crop suggest high levels of spatial flux in the arthropod assemblage. Aphid mortality rates (measured by prey removal and parasitism levels on sentinel plants) did not differ between the field edges and field centre in any of the three elevation zones, suggesting that for this Pest taxon, the centre of the fields still receive comparable Pest Control service as in the field edges. This study found that field margins around smallholder bean fields are useful habitats to large numbers of natural enemy taxa that move to adjacent crops providing Biological Pest Control service.
Niklas L. P. Lundström - One of the best experts on this subject based on the ideXlab platform.
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Pareto-efficient Biological Pest Control enable high efficacy at small costs
Ecological Modelling, 2017Co-Authors: Niklas L. P. Lundström, Hong Zhang, Åke BrännströmAbstract:Biological Pest Control is increasingly used in agriculture as an alternative to traditional chemical Pest Control. In many cases, this involves a one-off or periodic release of naturally occurring ...
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Pareto-efficient Biological Pest Control enable high efficacy at small costs
arXiv: Populations and Evolution, 2016Co-Authors: Niklas L. P. Lundström, Hong Zhang, Åke BrännströmAbstract:Biological Pest Control is increasingly used in agriculture as a an alternative to traditional chemical Pest Control. In many cases, this involves a one-off or periodic release of naturally occurring and/or genetically modified enemies such as predators, parasitoids, or pathogens. As the interaction between these enemies and the Pest is complex and the production of natural enemies potentially expensive, it is not surprising that both the efficacy and economic viability of Biological Pest Control are debated. Here, we investigate the performance of very simple Control strategies. In particular, we show how Pareto-efficient one-off or periodic release strategies, that optimally trade off between efficacy and economic viability, can be devised and used to enable high efficacy at small economic costs. We demonstrate our method on a Pest-pathogen-crop model with a tunable immigration rate of Pests. By analyzing this model, we demonstrate that simple Pareto-efficient one-off and periodic release strategies are efficacious and simultaneously have profits that are close to the theoretical maximum obtained by strategies optimizing only the profit. When the immigration rate of Pests is low to intermediate, one-off Control strategies are sufficient, and when the immigration of Pests is high, periodic release strategies are preferable. The methods presented here can be extended to more complex scenarios and be used to identify promising Biological Pest Control strategies in many circumstances.
Marta Montserrat - One of the best experts on this subject based on the ideXlab platform.
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food web engineering ecology and evolution to improve Biological Pest Control
Current opinion in insect science, 2021Co-Authors: Marta Montserrat, Diego Serranocarnero, Inmaculada Torrescampos, Mehdi Bohloolzadeh, Dolores Ruizlupion, Jordi MoyalaranoAbstract:If we are to sustainably provide food to a rapidly growing human population, Biological Pest Control (BPC) should integrate food web theory and evolution. This will account for the impacts of climate warming on the complex community settings of agroecosystems. We review recent studies looking for top-down augmentative Pest Control being hampered/promoted by biotic (community contexts) and/or abiotic (climate) drivers. Most studies found either positive or neutral effects on BPC. However, most ignored potential evolutionary responses occurring in the environments under study. We propose engineering food webs by engaging in a continuous feedback between ecological and evolutionary data, and individual-based modelling of agroecosystems. This should speed up the procurement of strains of efficient natural enemies better adapted to warming.
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Differential effects of abiotic conditions on fitness-related parameters of two Euseius species inhabiting avocado agro-ecosystems
BioControl, 2018Co-Authors: Celeste Guzmán, Rosa María Sahún, Marta MontserratAbstract:Temperature and relative humidity are important factors in shaping the structure and dynamics of communities composed of ectothermic species, as they directly affect fitness-related parameters and biotic interactions. In a climate change context, increased warming and dryness will likely affect arthropod communities of agro-ecosystems managed by Biological Pest Control. In this work, we compare, at the individual level, the functional relation between temperature and relative humidity and different life-history parameters in two sister predatory mite species that inhabit Spanish avocado crops, Euseius stipulatus and E. scutalis (Athias-Henriot) (Acari: Phytoseiidae). We found that negative effects of high temperature and low relative humidity were stronger in E. stipulatus than in E. scutalis. That E. scutalis tolerates very well hot and dry environments makes the species a good candidate to be considered in the future as a bioControl agent against Pests in subtropical and Mediterranean orchards.
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alternative food improves the combined effect of an omnivore and a predator on Biological Pest Control a case study in avocado orchards
Bulletin of Entomological Research, 2009Co-Authors: Jorge J Gonzalezfernandez, F De La Pena, J I Hormaza, Juan Ramon Boyero, Jose Miguel Vela, Eva Wong, Maria Del Mar Trigo, Marta MontserratAbstract:Ecological communities used in Biological Pest Control are usually represented as three-trophic level food chains with top-down Control. However, at least two factors complicate this simple way of characterizing agricultural communities. First, agro-ecosystems are composed of several interacting species forming complicated food webs. Second, the structure of agricultural communities may vary in time. Efficient Pest management approaches need to integrate these two factors to generate better predictions for Pest Control. In this work, we identified the food web components of an avocado agro-ecosystem, and unravelled patterns of co-occurrence and interactions between these components through field and laboratory experiments. This allowed us to predict community changes that would improve the performance of the naturally occurring predators and to test these predictions in field population experiments. Field surveys revealed that the food-web structure and species composition of the avocado community changed in time. In spring, the community was characterized by a linear food chain of Euseius stipulatus, an omnivorous mite, feeding on pollen. In the summer, E. stipulatus and a predatory mite, Neoseiulus californicus, shared a herbivorous mite prey. Laboratory experiments confirmed these trophic interactions and revealed that N. californicus can feed inside the prey nests, whereas E. stipulatus cannot, which may further reduce competition among predators. Finally, we artificially increased the coexistence of the two communities via addition of the non-herbivore food source (pollen) for the omnivore. This led to an increase in predator numbers and reduced populations of the herbivore. Therefore, the presence of pollen is expected to improve Pest Control in this system.