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Showing 1 to 7 of 7 for “"Rhinocyllus conicus"”.
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Impact of Rhinocyllus conicus Froelich (Coleoptera:Curculioniadae) on the reproduction of Carduus thistles in Virginia
… in 1973 and 75% in 1974 due to larval feeding of Rhinocyllus conicus. This was caused by heavy infestation of the early heads (45% in 1973, 70% in 1974) with a subsequent 5-fold increase in the number of weevil pupation chambers in these heads. Total seed production was reduced by 35-36% in both …
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Integrated control of Carduus thistles and ecological studies on Rhinocyllus conicus Froelich and Ceuthorhynchidius horridus (Panzer)
… developed using the biological control agents Rhinocyllus conicus Froelich and Ceuthorhynchidius horridus (Panzer) and the herbicide 2,4-Dichlorophenoxyacetic acid (2,4-D). Field studies on the development of Ceuthorhynchidius horridus (Panzer) on Carduus thistles in Virginia between 1975-1978 …
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Biological studies of Rhinocyllus conicus, Carduus thoermeri and a model of the interaction between these two species
… and the seasonal population dynamics of R. conicus was constructed based on a synthesis of the literature, and on laboratory experiments which determined developmental periods, mortality for immature stages and the ovipositional pattern of R. conicus. The model successfully simulated the …
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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.
Observations were carried out on the lifecycle of Rhinocyllus conicus (receptacle weevil) and growth forms of Carduus nutans (nodding thistle) from Nov. 1988 to June 1990 at Galatea in the central Bay of Plenty and on the coast at Whakatane. The dates of first emergence of adults in the spring, …
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Interactions between the rust fungus Puccinia carduorum Jacky and the musk thistle herbivores Trichosirocalus horridus (Panzer), Rhinocyllus conicus Froelich (Curculionidae: Coleoptera), and Cassida rubiginosa Muller (Coleoptera; Chrysomelidae)
… Trichosirocalus horridus (Panzer), rhinocvllus conicus Froelich, and Cassida rubiginosa Müller and their combined impact on must thistle, Carduus thoermeri Weinmann were studied.
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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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An analysis of the establishment and impact of an exotic insect, Rhinocyllus conicus Froehling (Coleoptera: Curculionidae), on Carduus nutans L. and Carduus acanthoides L. (Campanulatae: Compositae) in Virginia with notes on their biologies
… to evaluate the potential and effect of Rhinocyllus conicus as a biological control agent for Carduus nutans and C. acanthoides in Virginia. Over an 81 day range, 25 females oviposited an average of 100.5 eggs. Life expectancy did not differ between sexes. Examination of 1999 C. nutans …