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Series

1994

Department of Entomology: Faculty Publications

Articles 1 - 12 of 12

Full-Text Articles in Life Sciences

Characterization Of General Esterases From Susceptible And Parathion-Resistant Strains Of The Greenbug (Homoptera: Aphididae), Midori Ono, Jonathan S. Richman, Blair Siegfried Dec 1994

Characterization Of General Esterases From Susceptible And Parathion-Resistant Strains Of The Greenbug (Homoptera: Aphididae), Midori Ono, Jonathan S. Richman, Blair Siegfried

Department of Entomology: Faculty Publications

A susceptible and two parathion-resistant strains of the greenbug, Schizaphis graminum (Rondani), exhibit three different patterns of general esterase isozymes in native polyacrylamide electrophoresis gels. Characterization of general esterase activity using α -naphtholic esters as model substrates indicated that the three strains differed in isozyme composition. The type-I1 strain, which had the highest level of resistance, exhibited the highest levels of general esterase activity under all assay conditions, and the type-I strain had consistently higher levels than the susceptible strain. In all three strains, these esterases were more active toward α -naphtholic esters with side chains of six or fewer …

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Registration Of Eight Hessian Fly Resistant Common Winter Wheat Germplasm Lines (Carol, Erin, Flynn, Iris, Joy, Karen, Lola, And Molly), F. L. Patterson, F. B. Maas Iii, John E. Foster, R. H. Ratcliffe, S. Cambron, G. Safranski, P. L. Taylor, H. W. Ohm Jan 1994

Registration Of Eight Hessian Fly Resistant Common Winter Wheat Germplasm Lines (Carol, Erin, Flynn, Iris, Joy, Karen, Lola, And Molly), F. L. Patterson, F. B. Maas Iii, John E. Foster, R. H. Ratcliffe, S. Cambron, G. Safranski, P. L. Taylor, H. W. Ohm

Department of Entomology: Faculty Publications

Eight genes for resistance to Hessian fly, Mayetiola destructor (Say), were transferred individually by backcrossing and selfing into 'Newton' (Cl 17715) wheat (Triticum aestivum L.), a commercial hard red winter cultivar susceptible to all Hessian fly biotypes to which it has been tested. The eight germplasm lines (Table 1) were developed by the Purdue University Agricultural Experiment Station in cooperation with the USDAARS, with release in 1993. Newton is the source of the cytoplasm of the germplasm lines. Newton has a moderate level of winterhardiness suitable for commercial production in Kansas. The germplasm lines have not been tested adequately …

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Eicosanoids Mediate Insect Nodulation Responses To Bacterial Infections, Jon S. Miller, Tuanh Nguyen, David W. Stanley-Samuelson Jan 1994

Eicosanoids Mediate Insect Nodulation Responses To Bacterial Infections, Jon S. Miller, Tuanh Nguyen, David W. Stanley-Samuelson

Department of Entomology: Faculty Publications

We propose that nodule formation is mediated by eicosanoids in insects. Nodulation is the temporally and quantitatively predominant cellular defense response to bacterial infection in insects and other invertebrates. Inhibition of eicosanoid biosynthesis in larvae of the tobacco hornworn Manduca sexta immediately prior to intrahemocoelic infections with the bacterium Serratia marcescens strongly reduced the nodulation response. Inhibition of eicosanoid biosynthesis also reduced formation of cellular aggregates at 1 hr postinfection, which indicates that eicosanoids mediate early stages of nodulation. Separate treatments with specific inhibitors of phospholipase A2, cyclooxygenase, and lipoxygenase reduced nodulation, which supports the view that nodule …

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Screening Sunflower For Tolerance To Sunflower Midge Using The Synthetic Auxin 2,4-Dichlorophenoxyacetic Acid, Gary J. Brewer, Marc D. Anderson, N. V. Rama Raje Urs Jan 1994

Screening Sunflower For Tolerance To Sunflower Midge Using The Synthetic Auxin 2,4-Dichlorophenoxyacetic Acid, Gary J. Brewer, Marc D. Anderson, N. V. Rama Raje Urs

Department of Entomology: Faculty Publications

The sunflower midge, Contarinia schulzi Gagné, causes economic damage by inducing abnormal growth in infested heads (capitula) of sunflower, Helianthus annuus L. The primary objective of this study was to determine whether sunflower midge damage could be simulated and whether that simulated damage could be used to select midge-tolerant sunflower germplasm. An additional objective was to develop a quantitative alternative to the scoring systems used to visually estimate damage. Sunflower plants were treated by injecting buds with the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D), which resulted in a distortion of the head morphology that was similar in appearance to the damage …

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Patterns Among Host Plants Of Potato Leafhopper, Empoasca Fabae (Homoptera: Cicadellidae), William O. Lamp, Gary R. Nielsen, Stephen D. Danielson Jan 1994

Patterns Among Host Plants Of Potato Leafhopper, Empoasca Fabae (Homoptera: Cicadellidae), William O. Lamp, Gary R. Nielsen, Stephen D. Danielson

Department of Entomology: Faculty Publications

Ecological characteristics of potato leafhopper, Empoasca fabae (Harris), including polyphagy, suggest that non-economic plant species in the landscape may be important to its population ecology. The objectives of this study were to compile a host list, to ascertain taxonomic and ecological patterns within the list, and to determine host utilization in non-crop habitats. The host plant list included 220 species in 100 genera and 26 families. Fabaceae represented 47% of the genera and 62% of the species. Yet, the list includes a diversity of taxonomic groups within the class Magnoliopsida, representing highly divergent chemistry and morphological types. Ecological classifications, based …

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Subcellular Distribution And Characterization Of Esterase Isozymes From Insecticide-Resistant And -Susceptible Strains Of German Cockroach (Dictyoptera: Blatlellidae), Suresh K. Prabhakaran, Shripat T. Kamble Jan 1994

Subcellular Distribution And Characterization Of Esterase Isozymes From Insecticide-Resistant And -Susceptible Strains Of German Cockroach (Dictyoptera: Blatlellidae), Suresh K. Prabhakaran, Shripat T. Kamble

Department of Entomology: Faculty Publications

Esterases from insecticide-resistant and -susceptible strains of German cockroach, Blattella germanica (L.), were isolated and analyzed for differences in activity. The isozymes E5, E6, E7, and E8 of resistant strains indicated about two- to fivefold increases in activity compared with those of the susceptible strain. These isozymes constituted ≈60% of the total activity in the resistant strains, whereas they contributed only about 40% activity in the susceptible strain. Subcellular distribution studies showed that most esterase activity is present in the 100,000 x g fraction of the homogenate (cytosolic). Only a small portion of activity was membrane bound. Molecular weights of …

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Flight Behavior And Seasonal Trapping Of Rhynchophorus Cruentatus (Coleoptera: Curculionidae), Thomas J. Weissling, Robin M. Giblin-Davis, Barbara J. Center, Tak Hiyakawa Jan 1994

Flight Behavior And Seasonal Trapping Of Rhynchophorus Cruentatus (Coleoptera: Curculionidae), Thomas J. Weissling, Robin M. Giblin-Davis, Barbara J. Center, Tak Hiyakawa

Department of Entomology: Faculty Publications

Flight behavior, activity, and seasonal variation in capture of Rhynchophorus cruentatus (F.) were investigated. Response of R. cruentatus to traps baited with palm tissue was assessed at four locations in Florida over a 12- to 18-mo period. Capture of weevils varied by location and through time. Average temperature, the difference between high and low temperature, and total rainfall during trapping periods were not correlated with seasonal trends, but capture peaked in the spring following rise in temperature. Preflight behaviors of R. cruentatus were consistent for all weevils tested. Weevils preparing for flight first wipe their rostrum with the prothoracic legs, …

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Rice Pests In The Ivory Coast, West Africa: Farmers’ Perceptions And Management Strategies, A. A. Adesina, D. E. Johnson, E. A. Heinrichs Jan 1994

Rice Pests In The Ivory Coast, West Africa: Farmers’ Perceptions And Management Strategies, A. A. Adesina, D. E. Johnson, E. A. Heinrichs

Department of Entomology: Faculty Publications

An understanding of farmers’ perceptions of pests and their existing pest control methods can make an important contribution to the development of effective integrated pest management strategies. While the relatively successful rice IPM technologies in Asia have been extensively documented in studies examining farmers’ pest perceptions and management practices, studies examining, specifically, perceptions and management practices of West African rice farmers are rare. This may reflect the more limited success to date in the implementation of rice IPM strategies in the region. This paper describes rice pests, pest perceptions, and management practices of smallholder rice farmers in the Ivory Coast. …

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Fecundity And Fertility Of Rhynchophorus Cruentatus (Coleoptera: Curculionidae), Thomas J. Weissling, Robin M. Giblin-Davis Jan 1994

Fecundity And Fertility Of Rhynchophorus Cruentatus (Coleoptera: Curculionidae), Thomas J. Weissling, Robin M. Giblin-Davis

Department of Entomology: Faculty Publications

The palmetto weevil (R. cruentatus F.) breeds in a variety of stressed or dying palms (Giblin-Davis & Howard 1988, 1989). These large (1.9 - 3.0 cm long) weevils are associated with the native cabbage palmetto, Sabal palmetto (Walter), in Florida (Woodruff 1967). Semiochemicals emanating from stressed or dying palms and male conspecifics (Weissling et al. 1992, 1993, 1994, Giblin-Davis et al. 1994) are attractive to R. cruentatus adults. Although not fully understood, mating apparently takes place on dying palms and females lay their eggs in the leaf bases or directly into the wounds of the host. Larvae develop primarily …

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Population Genetics And Gene Variation In Primary And Secondary Screwworm (Diptera : Calliphoridae), David B. Taylor, Richard D. Peterson Ii Jan 1994

Population Genetics And Gene Variation In Primary And Secondary Screwworm (Diptera : Calliphoridae), David B. Taylor, Richard D. Peterson Ii

Department of Entomology: Faculty Publications

Allozyme variation in screwworm, Cochliomyia hominivorax (Coquerel), and secondary screwworm, C. macellaria (F.), populations from northwest Costa Rica was examined . Variability was observed in 11 of 13 enzyme loci and the frequency of the most common allele was <0.95 for 5 loci in screwworm . In secondary screwworm, 12 of 13 loci were variable and the frequency of the most common allele was <0.95 for 6 loci . Expected heterozygosities were 0.149 and 0.160 for screwworm and secondary screwworm, respectively. Goodness-of-fit statistics for Hardy-Weinberg equilibrium and Wrights F statistics indicated that both species are panmictic with no evidence of population substructuring. Nei ' s genetic distances were 0.000–0.001 for intraspecific comparisons and 0.899–0.916 for interspecific comparisons. The data indicate a high level of gene flow between populations within each species.

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Development Of Multiple Pest Resistant Crop Cultivars, Elvis A. Heinrichs Jan 1994

Development Of Multiple Pest Resistant Crop Cultivars, Elvis A. Heinrichs

Department of Entomology: Faculty Publications

Insects are one, among a number, of biotic and abiotic constraints that limit the production of food crops. Entomologists can play a key role in increasing food production through the development of insect-resistant crop cultivars. Resistant cultivars are sought as a major tactic in the development of IPM strategies and have been shown to be compatible with biological, chemical and cultural control tactics. There has been significant progress in the breeding and commercial utilization of multiple pest resistant crop cultivars having resistance to insects, diseases and nematodes. The most notable examples are rice cultivars which are grown on millions of …

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Passive Trap For Monitoring Codling Moth (Lepidoptera: Tortricidae) Flight Activity, Thomas J. Weissling, Alan L. Knight Jan 1994

Passive Trap For Monitoring Codling Moth (Lepidoptera: Tortricidae) Flight Activity, Thomas J. Weissling, Alan L. Knight

Department of Entomology: Faculty Publications

A new passive trap, constructed of rigid, clear plastic panes (0.3 m by 0.3 m), coated with an STP Oil Treatment film as an adhesive, was developed for monitoring codling moth, Cydia pomonella (L.), movement within and between orchard canopies. Tests showed that the trap was effective in recapturing released codling moth adults, that the adhesive was not attractive to moths, and that the adhesive was still effective after remaining on a trap for 1 wk in the field. Field experiments demonstrated that the passive pane-trap method is as efficient for catching moths as molasses-baited traps but that it is …

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