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Showing 1 to 20 of 102 for “"natural enemies"”.
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Teachers Working with Families: Natural Enemies or Necessary Allies?
<p>The complex and crucial connection between families and schools is embodied in relationship between individual teachers and their students' families. Research findings demonstrate that high levels of family engagement lead to greater success for students. Such findings drive policy mandates that …
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Influence of Selective Insecticides and Cropping System on Arthropod Natural Enemies in Soybean
Arthropod natural enemies play a key role in controlling potentially damaging pest populations in agroecosystems. An abundant and diverse natural enemy community is associated with higher yields in a variety of crops. Certain aspects of soybean production can make a field more or less amenable to a …
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Effects of Natural Enemies and Host Condition on Populations of Insect Pests of Trees
In the third chapter, I reviewed the primary and secondary literature on parasitoids of the wood-boring larvae of cerambycid beetles to examine the relationship between the feeding niche of beetles and the number and types of parasitoids that attack them. Significantly fewer species of parasitoids …
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Use of sensory information by cerambycids and their natural enemies to locate resources and mates
… the cues and signals that cerambycids and their natural enemies use to locate mates and resources. Many species of longhorned beetles (Coleoptera: Cerambycidae) prefer to feed in trees that are stressed, weakened, or in the process of dying. These resources are ephemeral, disappearing rapidly as …
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Combined Roles of Glandular-haired Alfalfa and Natural Enemies in Alfalfa Pest Managment in Virginia
… impact of glandular-haired alfalfa on the natural enemies of alfalfa weevil was examined as well. <i>Bathyplectes anurus</i> (Thompson) (Hymenoptera: Ichneumonidae) was the dominant parasitoid attacking weevil larvae at both locations. Parasitization of weevil larvae by <i>Bathyplectes</i> …
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Not natural enemies : working to improve compatibility between industrial and residential land uses in Jamaica Plain
Thesis (M.C.P.)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 1990.
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Euonymus scale, Unaspis euonymi (Comstock): host preference, and distribution of native and imported natural enemies in Virginia
… conducted to determine the presence of existing natural enemies in Virginia as well as to determine the establishment of the imported predator, Chilocarus kuwanae. In 1992, C. kuwanae and parasites from the genera Aspidiatiphagus and Encarsia was found at several locations in Virginia Beach. In …
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The Use of Buckwheat Border Habitats to Attract Natural Enemies of Cucumber Beetles in a Cucurbit Agroecosystem
… esculentum Moench) border habitat to attract the natural enemies, Celatoria diabroticae (Shimer) and Celatoria setosa (Coquillett) (both Diptera: Tachinidae) and Chauliognathus pennsylvanicus (Deg.) (Coleoptera: Cantharidae). Five different plants were seeded in the border and buckwheat dominated. …
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Plant diversity and its effects on populations of cucumber beetles and their natural enemies in a cucurbit agroecosystem
Populations of striped cucumber beetles (<i>Acalymma vittatum</i> Fabr.), spotted cucumber beetles (<i>Diabrotica undecimpunctata howardi</i> Barber), western cucumber beetles (<i>Acalymma trivittatum</i> Mann.), Pennsylvania leatherwings (<i>Chauliognathus pennsylvanicus</i> DeGeer), Diptera …
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Do Mosquito Pesticides Harm Their Natural Enemies? Ecological Impacts and Non-Target Effects of Larvicides on Mosquito Predators
<p>Larvicides are chemicals used to kill juvenile mosquitoes. When applied to an area, other aquatic organisms are exposed to these chemicals. The removal or impairment of top insect predators could be beneficial to mosquito populations once harmful pesticide levels dissipate. Two common larvicides …
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Combining natural enemies and selective pesticides in IPM programmes of exotic pests: the Tuta absoluta (Lepidoptera: Gelechiidae) case
The recent invasion of the Mediterranean basin by the South American tomato pinworm, Tuta absoluta (Lepidoptera: Gelechiidae), has lead to a swift increase in insecticide applications in tomato crops. Such increase may compromise the tomato Integrated Pest Management (IPM) packages that were …
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Spatial ecology of an insect host-parasitoid-virus interaction: the winter moth (Operophtera brumata) and its natural enemies in Orkney
Understanding the population dynamics of host-natural enemy interactions in spatially heterogeneous habitats may help mitigate the negative effects of environmental change. The aim of this thesis is to investigate the role of spatial processes in determining the distribution and abundance of two …
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Worldwide spatial distribution of Tuta absoluta (Lepidoptera: Gelechiidae) and its natural enemies under current and future climatic change conditions through modelling
… effect of climate change on it and four of its natural enemies (Neochrysocharis formosa, Stenomesius japonicus, Pseudapanteles dignus, and Macrolophus pygmaeus). We modelled the areas under risk and the effect of climate change on the pest and its natural enemies using CLIMEX and MaxEnt. …
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Barcoding alien invertebrates and biological control agents in South Africa, with a focus on the natural enemies of Thaumatotibia leucotreta (Meyrick)
… sampled in the Western Cape suggests that natural wasp populations may be insufficient for pest control, supporting the case for augmentative biological control whilst highlighting the need for more intensive sampling and trials of parasitoid wasps as biological control agents. Using …
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Effects of Prior Defoliation on the Timing of Life Cycle Events and Susceptibility to Natural Enemies of a Host Specific Gall-Former
… (Past: 0-50%, Recent: 0-13%) in the presence of natural enemies. These shifts in conjunction with past and recent defoliation of live oaks by oak leaf rollers (which alter the timing of tissue formation coinciding with B. treatae oviposition) motivated a defoliation experiment inducing variation …
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The natural enemies of Asparagus asparagoides (L.) Wight in South Africa and their potential for use as biological control agents in Australia
… A. asparagoides in South Africa, as well as the natural enemies associated with the plant and their potential for use as biological control agents in Australia. Potential biological control agents that attack vegetative growth of bridal creeper included an undescribed Zygina sp. (Cicadellidae), …
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Influence of cover crop management on Armyworm, Pseudaletia Unipuncta (Haworth) seasonal abundance, natural enemies, and yield in no-till corn, and diurnal abundance and spatial distribution of Armyworm
Rye (<i>Secale cereale</i> L.) used as a winter cover crop was killed by paraquat or by mowing with a bushog. In subsequent no-till corn, early season armyworm, <i>Pseudaletia unipuncta</i> (Lepidoptera: Noctuidae) abundance was lower in the mowed treatment compared with the sprayed treatment. …
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Impact of Natural Mortality Factors on Populations of the European Corn Borer in Bt- and Non-Bt-Corn Fields in Illinois
… were conducted to evaluate the incidence of natural enemies of European corn borer in Bt cornfields. The findings were compared with assessments of the effects of natural enemies in non-Bt cornfields. In my study, corn type did not seem to affect the percentage of eggs parasitized by …
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Assessing the drivers of adaptive radiation in a complex of gall midges: A multitrophic perspective on ecological speciation
Natural enemies as selective forces maintaining and shaping morphological, physiological, and behavioral divergence in adaptive radiations have received very little attention. Until recently, the focus has been on primary resource competition as a major driver of trait divergence in adaptive …
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Effect of Intercropping and Trap Cropping on the Diamondback Moth, Plutella Xylostella L., Its Natural Enemies and Other Brassicaceous Pests, And, Studies on Diadegma Insulare (Cresson), the Major Diamondback Moth Parasitoid
Laboratory studies on D. insulare revealed that it was better synchronized with its host when it developed in second instars, where survival to cocoon formation and adult emergence was also significantly higher than in third- or fourth-instar hosts. A greenhouse study at varying parasitoid and host …
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