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Showing 1 to 20 of 43 for “"weevils"”.
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Phytochemical mediated resistance in sweetpotato to sweetpotato weevils
… evaluated sweetpotato resistance to sweet potato weevils (Cylas spp.) and investigated the phytochemicals that mediated this defence. New Kawogo, LIR302 and ARA228 were shown to be the most resistant based on stem and root damage. Significant differences were observed on the number of faecal …
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A Comparison of the Viability of Thistle Weevils From Fire Ant Suppressed Site to Weevils From a Site Where Fire Ants Were Not Suppressed
<p>The thistle weevil, <em>Rhinocyllus conicus</em>, was introduced to the United States as an agent of biological control for another non-native species, the musk thistle,<em> Carduus nutans</em>. Musk thistle are noxious weeds of pastures which reduce forage for grazing livestock. A high weevil …
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Morphology, phylogeny, and evolutionary development in the weevils (Insecta: Coleoptera: Curculionoidea)
Weevils (superfamily Curculionoidea) rank among the most diverse groups of extant organisms, with ~60,000 described species. They are extremely important economically, being of great agricultural significance because they associate with all major groups of plants, often with negative consequences …
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Systematics and evolutionary biology of the Weevils associated with cycads in Australia
… four genera and approximately 90 named species. Weevils play significant roles in pollination of Australian cycads, although some species are also pollinated or co-pollinated by some genera and species of the beetle families Boganiidae and Erotylidae and thrips. While it is now established that …
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Systematics and evolutionary biology of the Weevils associated with cycads in Australia
… four genera and approximately 90 named species. Weevils play significant roles in pollination of Australian cycads, although some species are also pollinated or co-pollinated by some genera and species of the beetle families Boganiidae and Erotylidae and thrips. While it is now established that …
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Population genetics prior to biological control: Ceutorhynchus weevils proposed for managing garlic mustard
I studied the population genetic structure of three weevil species, Ceutorhynchus alliariae, C. roberti, and C. scrobicollis, being considered for the biological control of garlic mustard, Alliaria petiolata, in North America. My first objective was to develop a polymerase chain …
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Are Weevils Picky Eaters? Community Structure and Host Specificity of Neotropical Saproxylic Beetles (Coleoptera: Curculionidae)
… richness (N = 33) and abundance. Fourteen weevils were host specialists. Nine ambrosia beetles were host specialists, associated with either Lecythidaceae or Fabaceae (legume family). Secondary forest yielded the highest number of forest stage specialist species (N = 18). Ground stratum in …
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Sublethal effects by deltamethrin and spinosad on the grain weevils Sitophilus zeamais and S. granarius
… Little is known about such effects on grain weevils. In this context, we evaluated the sublethal effects by deltamethrin and spinosad on two species of grain weevils (Sitophilus zeamais e S. granarius). In the first experiment, we evaluated the insecticide effect of deltamethrin and spinosad …
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Trophic Interactions And The Efficacy Of Milfoil Weevils For Biocontrol Of Eurasian Watermilfoil In Wisconsin Lakes
… predation may account for high weevil mortality. Weevils were augmented in 4 northern Wisconsin lakes in summer 2013. In summer 2014, I collected invertebrates associated with EWM plus 442 bluegill (Lepomis macrochirus Rafinesque) diet samples from the 4 study lakes. Overall, chironomids and …
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Adaptation to the host-plant, and the evolution of host specialization, in 'cycad weevils' (Coleoptera: Brentidae)
… in an enigmatic and seemingly primitive group of weevils belonging to the genus Antliarhinus (Coleoptera: Brentidae). These beetles occur only on species of the cycad genus Encephalartos and appear to retain an ancient association with cycads, a group of plants that were widespread in the Mesozoic …
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Biology and natural control of the white pine weevil, Pissodes strobi (Peck), in Virginia
… the white pine weevil were studied by dissecting weevils at various intervals throughout the winter. Old-generation adults brought into the laboratory November produced viable eggs within 5 days. New generation adults brought into the laboratory on November 4 produced viable eggs during November. …
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Mating behavior of the alfalfa weevil, Hypera postica (Gyllenhal)
… were studied in the laboratory. Postdiapausing weevils, collected in April, and nondiapausing weevils, reared in the laboratory, were utilized. In both groups, the males aggressively mounted the females from any angle or position with little or no indication of prior courtship. In petri dishes …
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The reproductive seasonality and flight capability of Sitona discoideus Gyllenhal (Coleoptera: Curculionidae) and its pattern of larval establishment in Canterbury lucerne
… This work confirmed that the univoltine adult weevils entered aestivatory diapause some three to four weeks after the eclosion of the new generation in December-January each year. Flight to aestivation sites remote from the host crop, was preceded by a vigorous feeding phase during which time …
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Development of female sex organs during aestivation in the alfalfa weevil, Hypera postica (Gyll.) (Coleoptera, Curculionidae)
… of female sex organs were made in dissected weevils at monthly intervals to observe each of the developmental stages of sexual maturation. Results of this sexual development as it progressed after adult emergence, were presented by means of tables, graphs, and a series of photographs. The …
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Behavioural interactions between the large pine weevil, Hylobius abietis L.(Coleoptera: Curculionidae), and entomopathogenic nematodes
… were applied to the head region of adult weevils and grooming responses were recorded (Chapter 3). Insects that had Steinernema carpocapsae applied on average groomed for significantly longer (44.16 seconds), than those that had Heterorhabditis downesi applied (11.33 seconds). In order to …
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Aspects of the biology of the receptacle weevil, Rhinocyllus conicus (Froehlich) relating to its role as a biocontrol agent of nodding thistle, Carduus nutans L.
… investigated by microscopic dissection. Adult weevils were shown to disappear from the field in mid-summer and to hibernate from June to September-October. Hibernation sites are hard to find, and remain an unsolved problem. The phenology of nodding thistle in relation to the life-cycle of R. …
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Biological control of Acacia cyclops in South Africa : the role of an introduced seed-feeding weevil, Melanterius servulus (Coleoptera: Curculionidae), together with indigenous seed-sucking bugs and birds
… of indigenous seed-sucking bugs and birds. The weevils utilise filled green pods of A. cyclops for adult feeding, oviposition and larval development and completely destroy seeds during these activities. Examination of the reproductive phenology of A. cyclops showed that seeds are produced …
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Effectiveness of Root-Boring Knapweed Weevil (Cyphocleonus achates Fåhr.) Herbivory on Spotted Knapweed (Centaurea stoebe Lam.) in Kamloops, BC: A Five-year Review
… agents. In 2017 and 2018, root-boring knapweed weevils were released at 15 sites across Kamloops, BC, Canada. This study is a five-year follow-up on the possible effects of C. achates on spotted knapweed density, distribution, and vigour. The presence of weevils was determined by destructive …
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