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K P Pruess

Publications and source records attributed to K P Pruess.

4 recordsLinked to original sources
PubMed1998

Greenbug (Homoptera: Aphididae) biotypes characterized using random amplified polymorphic DNA.

Genomic DNA was extracted from seven greenbug, Schizaphis graminum, biotypes (B, C, E, F, G, H and I) obtained from laboratory colonies maintained by USDA-ARS, Stillwater, Oklahoma. DNA was amplified using single 10-base primers. Of 100 primers tested, four were found which either alone, or in combination, distinguished all biotypes by distinct size differences in amplified fragments. Results were repeatable using aphids obtained from the same colonies 2 years later. These diagnostic primers produced unvarying banding patterns for all biotype E greenbugs collected in the field in Nebraska, Kansas, Oklahoma, and Texas.

Animals↗
PubMed1998

Effects of preservation methods, parasites, and gut contents of black flies (Diptera: Simuliidae) on polymerase chain reaction products.

Molecular analysis of biological specimens usually requires extraction of high-molecular weight DNA free of foreign DNA contaminants. DNA was extracted from black flies at different life stages that had been preserved by 4 methods: larvae and adults in ethanol, larvae in Carnoy's solution, adults on card-points, and adults hand-swatted and sun-dried. Using specific primers for the mitochondrial ND4 gene, a 257-bp amplicon was obtained from specimens preserved by ethanol, card-point mounting, and sun-drying. Successful amplification often required DNA dilutions > or = 1:20 (< 1-10 ng). DNA from specimens preserved in Carnoy's solution (ethanol: acetic acid, 3:1) yielded degraded DNA, resulting in fewer successful amplications. Parasitic nematodes and, to a lesser extent, gut contents resulted in extra products when amplified with randomly amplified polymorphic DNA (RAPD) primers. Sufficient DNA was extracted from the head of a larva for a successful polymerase chain reaction (PCR), eliminating the need to remove the contaminating gut and parasites.

Animals↗
PubMed1992

Mitochondrial transfer RNA genes in a black fly, Simulium vittatum (Diptera: Simuliidae), indicate long divergence from mosquito (Diptera: Culicidae) and fruit fly (Diptera: Drosophilidae).

Sequences are given for nine complete genes and one partial mitochondrial tRNA gene of the black fly, Simulium vittatum (Zetterstedt). Sequenced tRNA genes were for alanine, arginine, asparagine, aspartic acid, glutamic acid, glycine, leucine(CUN), lysine, serine(AGN), and valine. Nucleotides were aligned with the same previously sequenced genes in Aedes albopictus Skuse and Drosophila yakuba Burla. A cluster of six tRNA genes, which differ in arrangement in Ae. albopictus and D. yakuba, was amplified by PCR and found to have the same position and orientation in S. vittatum as in D. yakuba. Overall, similarity with either D. yakuba or Ae. albopictus was 86%. Sequences that were common to the three insects suggest that black flies and mosquitoes are as divergent from each other as either is from Drosophila. Sequences for nine species of black flies were obtained for tRNA leucine(CUN) from DNA amplified with another primer set. Little variation occurred within the tRNA gene but, by including the flanking regions to provide 175 base pairs, a phylogeny of the nine species was obtained that was largely consistent with current classification.

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