67 research outputs found

    The bumble bees (Hymenoptera: Apidae: Bombus) of Arkansas, fifty years later

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    Many species of bumble bees (Hymenoptera: Apidae: Bombus Latreille) are declining throughout their ranges in North America, yet detecting population trends can be difficult when historical survey data are lacking.  In the present study, contemporary data is compared to a 1965 survey to detect changes in bumble bee distributions throughout Arkansas.  Using county-level records as a point of comparison to look for changes in state-wide occurrence among species over time, we find that state-level changes reflect national trends.  Contemporary records of Bombus bimaculatus Cresson and B. impatiens Cresson have more than tripled, while records for B. pensylvanicus (De Geer) show a decline to 61% of historical levels.  Although B. fervidus (Fabricius) has been reported infrequently in the state, misidentifications may have led to an overestimation of the state’s species richness.  In addition to an updated assessment of the bumble bees of Arkansas, we also provide new, localized information on the seasonal phenology and plant preferences of each species that can be used to guide conservation efforts

    Identification of \u3ci\u3eMuscidifurax\u3c/i\u3e Spp. by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism

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    Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the nuclear ribosomal ITS1 region was used to differentiate Muscidifurax (Hymenoptera: Pteromalidae) species which are parasitoids of filth fly pupae. Three restriction enzymes, Dpn 11, Mse I, and Taq I, produced restriction patterns which were diagnostic for the four species analyzed, M. raptor, M. raptorellus, M. uniraptor, and M. zaraptor. Seven other restriction enzymes were able to differentiate one or more of the species and can be used alone, or in combination with other enzymes, to verify identifications. No intraspecific variation was observed among the populations examined. The utility of the PCR-RFLP technique compared with other moIecuIar and biochemical diagnostic procedures is discussed

    Molecular Diagnostics of Three \u3ci\u3eDiabrotica\u3c/i\u3e (Coleoptera: Chrysomelidae) Pest Species

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    A 257 bp region of the mitochondrial ND4 gene was analyzed for genetic variation in three species of corn rootworm, southern corn rootworm (Diabrotica undecim punctata howardi Barber, SCR), northern corn rootworm (D. barberi Smith and Lawrence, NCR), and western corn rootworm (D. virgifera virgifera LeConte, WCR). Nucleotide sequencing revealed 26 polymorphic sites. Genetic distances averaged 8% for all pair-wise comparisons among the three species. Restriction maps were constructed from sequence data and compared to potential species specific restriction sites. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) revealed three restriction enzymes (Alu I, Apo I and Sau 3A) which produced diagnostic patterns for both adults and larvae. Only NCR showed intraspecific polymorphism

    Molecular Diagnostics of Three \u3ci\u3eDiabrotica\u3c/i\u3e (Coleoptera: Chrysomelidae) Pest Species

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    A 257 bp region of the mitochondrial ND4 gene was analyzed for genetic variation in three species of corn rootworm, southern corn rootworm (Diabrotica undecim punctata howardi Barber, SCR), northern corn rootworm (D. barberi Smith and Lawrence, NCR), and western corn rootworm (D. virgifera virgifera LeConte, WCR). Nucleotide sequencing revealed 26 polymorphic sites. Genetic distances averaged 8% for all pair-wise comparisons among the three species. Restriction maps were constructed from sequence data and compared to potential species specific restriction sites. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) revealed three restriction enzymes (Alu I, Apo I and Sau 3A) which produced diagnostic patterns for both adults and larvae. Only NCR showed intraspecific polymorphism

    Population Genetic Structure of Nebraska Paddlefish Based on Mitochondrial DNA Variation

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    Eighty-three paddlefish Polyodon spathula that were collected from 1995 to 1999 from the Missouri River Galvins Point Dam tailwater were analyzed for genetic variation in the mitochondrial DNA d-loop region. Additional samples from Montana, South Dakota, and Louisiana were used for comparative purposes. To facilitate the efficient analysis of numerous paddlefish samples, we applied a method that employs polyacrylamide gel electrophoresis (PAGE) to resolve restriction fragment length polymorphisms (RFLPs) amplified by polymerase chain reaction (PCR). DNA sequencing of 10 paddlefish revealed 22 polymorphic sites. Polymerase chain reaction–RFLP analysis of 93 paddlefish using three restriction enzymes detected six of the polymorphic sites and revealed six distinct haplotypes. All of the observed haplotypes were found in the Missouri River Galvins Point Dam tailwater. No temporal differentiation was observed among the 1995, 1998, and 1999 samples from the Missouri River Galvins Point Dam tailwater. Polymerase chain reaction–RFLP, resolved with PAGE, provided an efficient method for population genetic analysis of paddlefish

    Population Genetic Structure of Nebraska Paddlefish Based on Mitochondrial DNA Variation

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    Eighty-three paddlefish Polyodon spathula that were collected from 1995 to 1999 from the Missouri River Galvins Point Dam tailwater were analyzed for genetic variation in the mitochondrial DNA d-loop region. Additional samples from Montana, South Dakota, and Louisiana were used for comparative purposes. To facilitate the efficient analysis of numerous paddlefish samples, we applied a method that employs polyacrylamide gel electrophoresis (PAGE) to resolve restriction fragment length polymorphisms (RFLPs) amplified by polymerase chain reaction (PCR). DNA sequencing of 10 paddlefish revealed 22 polymorphic sites. Polymerase chain reaction–RFLP analysis of 93 paddlefish using three restriction enzymes detected six of the polymorphic sites and revealed six distinct haplotypes. All of the observed haplotypes were found in the Missouri River Galvins Point Dam tailwater. No temporal differentiation was observed among the 1995, 1998, and 1999 samples from the Missouri River Galvins Point Dam tailwater. Polymerase chain reaction–RFLP, resolved with PAGE, provided an efficient method for population genetic analysis of paddlefish

    Nuclear Ribosomal ITS Region Sequences for Differentiation of Rubus Genotypes

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    Previous molecular investigations into Rubus species diversity have yielded significant knowledge about species relatedness. However, little work has been focused at the cultivar level. Random amplified polymorphic DNA(RAPD)-PCR studies have successfully differentiated closely related cultivars. The ability to definitively distinguish blackberry and red raspberry cultivars based on other molecular methods could prove useful in many aspects of breeding and proprietary protection. In this study, the nuclear ribosomal DNA internal transcribed spacer regions (ITS) of six Rubus cultivars were sequenced. DNA sequencing revealed little genetic variation among blackberry cultivars, but revealed distinctions between blackberry and red raspberry cultivars. Analysis by maximum-parsimony and maximum-likelihood confirmed the small variation among blackberry cultivars, although cultivars Apache, Brazos, and APF-12 did organize a weak sub-cluster within the blackberry genotypes. However, ITS region sequences do not appear to differentiate among closely related blackberry genotypes for purposes of cultivar discrimination or plant patent protection

    Genetic Variation in the Midcontinental Population of Sandhill Cranes, \u3ci\u3eGrus Canadensis\u3c/i\u3e

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    Three subspecies of sandhill crane (Grus canadensis) are recognized in the Midcontinental population, the lesser (Grus c. canadensis), Canadian (G. c. rowani), and greater (G. c. tabida). Blood samples collected on the population’s primary spring staging area in Nebraska, U.S.A., were used to resolve the genetic relationship among these subspecies. Phylogenetic analysis of 27 G. canadensis, by DNA sequencing of a 675 bp region of the mtDNA, supports the subspecies designations of G. c. canadensis and G. c. tabida. G. c. rowani individuals were intermediate with each of the other two subspecies. Genetic divergence ranged from 6.5 to 14.5% between G. c. canadensis and G. c. tabida, 0.5 to 6.6% within G. c. canadensis, and 0.1 to 6.0% within G. c. tabida. Sufficient DNA for analysis was obtained from shed feathers indicating a source of genetic material that does not require the capture or sacrifice of the birds. Other genetic markers and methods, including satellite telemetry, are required for obtaining detailed information on crane distributions as needed to establish effective management units for the MCP
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