Life Sciences Commons^™

Insect Resistant Rice, Maize And Wheat Cultivars In Sustainable Agriculture, E. A. Heinrichs, J. E. Foster

Department of Entomology: Faculty Publications

The achievement of self sufficiency in food production is a major objective of governments throughout the world. Insects are one of the major constraints that limit the production of food crops. To mitigate losses due to insects. insect resistant cultivars are sought as a major tactic in the development of integrated pest management strategies. The integration of insect resistant cultivars with other pest management tactics contributes to crop pest management strategies that are environmentally and economically acceptable. Multiple pest resistant crop cultivars have high yield stability when grown in pest-infested environments. Significant progress on a global basis has been achieved …

Differential Toxicity Of Atrazine To Selected Freshwater Algae, J.-X. Tang, Kyle D. Hoagland, Blair D. Siegfried

Department of Entomology: Faculty Publications

The documented presence of atrazine in surface waters has prompted a large number of studies on its potential adverse effects on nontarget organisms such as freshwater algae, which are the most important primary producers in aquatic habitats and are potential indicators of water quality (Blaise 1993). Recently, a comprehensive database of the ecological effects of atrazine, including 85 freshwater organisms, was compiled (Solomon et al. 1996). Based on this compilation of acute ( ≤ 4 day) or chronic (> 9 day) toxicity values, algae are the most susceptible aquatic organisms to atrazine, although it is apparent that different species and …

Use Of Rubidium To Label Lysiphlebus Testaceipes (Hymenoptera: Braconidae), A Parasitoid Of Greenbugs (Homoptera: Aphididae), For Dispersal Studies, Odair A. Fernandes, Robert J. Wright, Karl H. Baumgarten, Z. B. Mayo

Department of Entomology: Faculty Publications

A reliable method of labeling is needed to study dispersal of the braconid parasitoid, Lysiphlebus testaceipes (Cresson), an important biological control of greenbugs, Schizaphis graminum (Rondani), on grain sorghum, Sorghum bicolor (L.) Moench. The feasibility of using aqueous solutions of rubidium chloride (RbCl) applied as a foliar spray or soil drench to label greenbugs and L. testaceipes developing within greenbugs was studied. Laboratory and field studies were conducted to identify the minimal concentration of RbCl to assure labeling of greenbugs and wasps, persistence of Rb throughout the wasp's life span, mobility of Rb to unsprayed sorghum leaves, and feasibility of …

Toxicity Of Seven Monoterpenoids To Tracheal Mites (Acari: Tarsonemidae) And Their Honey Bee (Hymenoptera: Apidae) Hosts When Applied As Fumigants, Marion D. Ellis, Frederick P. Baxendale

Department of Entomology: Faculty Publications

Laboratory bioassays were conducted to characterize the acute toxicity of 7 monoterpenoids to tracheal mites, Acarapis woodi (Rennie), and their honey bee, Apis mellifera L., hosts. Citral, thymol, carvacrol, α-terpineol, pulegone, d-limonene, and menthol were applied as fumigants to mite-infested honey bees. Thymol and menthol were the most toxic compounds to honey bees, and α-terpineol was the least toxic. Menthol, citral, thymol, and carvacrol were more toxic to tracheal mites than to honey bees. Pulegone, d-limonene, and α-terpineol were more toxic to honey bees than to tracheal mites. Menthol was 18.9 times more toxic to tracheal mites than to …

Riparian Refugia In Agroforestry Systems, Mary Ellen Dix, Erol Akkuzu, Ned B. Klopfenstein, Jianwei Zhang, Mee-Sook Kim, John E. Foster

Department of Entomology: Faculty Publications

In the last 200 years, cultivation, grazing, and other activities initiated by humans have destroyed more than 80 percent of the strips of vegetation along North American and European streams and other bodies of water (Decamps and Naiman 1989; Petts et al. 1989). This disappearance of the riparian zones is continuing with little concern for ecological consequences. At the same time, riparian buffer strips are being promoted as a preferred management practice in the United States, especially in the Great Plains, to protect water resources from soil and chemical pollution (Schoeneberger 1994; Schoeneberger et al. 1995; Schultz et al. 1995a; …

Insect Pests And Arthropod Predators Associated With Tree-Turf Landscapes, Mary Ellen Dix, Frederick P. Baxendale

Department of Entomology: Faculty Publications

Sweep-nets and pitfall traps were used to examine the distribution and dynamics of predominant predators and pests in turfgrass foliage in parks, golf courses and suburban/rural landscapes in 1991 and 1992. Araneae, Formicidae, and Coccinellidae were the most abundant predators in the sweeps, while Araneae, Formicidae, and) Carabidae were the most abundant predators in the pitfall traps. In both years, Araneae comprised over 60% of the total predators in the sweep samples. Formicidae (>70%) and Araneae (13-19%) were the most abundant arthropod predators in the pitfall samples. Cicadellidae, Chrysomelidae, and Orthoptera accounted for over 96% of the prey in …

Susceptibility Of Stable Flies (Diptera: Muscidae) From Southeastern Nebraska Beef Cattle Feedlots To Selected Insecticides And Comparison Of 3 Bioassay Techniques, Paula C. R. G. Marcon, Gustave D. Thomas, Blair Siegfried, John B. Campbell

Department of Entomology: Faculty Publications

Insecticide susceptibility of field populations of stable flies, tomoxys calcitrans (L.), was assayed using 3 exposure techniques: treated filter papers, treated glass petri dishes, and topical applications. Both topical applications and residual exposure to treated glass surfaces were suitable for testing susceptibility of stable flies to permethrin, stirofos, or methoxychlor. Residues on filter papers yielded inconsistent results with stirofos and methoxychlor. Significant concentration-mortality regression lines were generated with permethrin residues on filter papers, but ~1,000 times more insecticide was required to produce a toxic response when compared with permethrin residues on glass. Because of higher variability in response and the …

Effects Of Shelterbelts On The Aerial Distribution Of Insect Pests In Muskmelon, Mary Ellen Dix, Laurie Hodges, James R. Brandle, Robert J. Wright, Mark O. Harrell

Department of Entomology: Faculty Publications

Sticky traps were used to measure how tree shelterbelts influence the abundance of crop insect pests and beneficial arthropods in muskmelon (Cucumis melo L.) plots in eastern Nebraska. Abundance of striped cucumber beetles {Acalymma vittatum Fabricius (Coleoptera: Chrysomelidae)} , southern corn rootworms {Diabrotica undecimpunctata howardi Barber (Coleoptera: Chrysomelidae)}, and northern corn rootworms {D. barberi Smith & Lawrence (Coleoptera: Chrysomelidae)} was similar in exposed and sheltered plots. Western corn rootworms {D. virgifera LeConte (Coleoptera: Chrysomelidae)} were significantly more abundant in exposed plots. More lady beetles (Coleoptera: Coccinellidae) and ichneumonid wasps (Hymenoptera: Ichneumonidae) were caught on traps …

United States Patent: 315 Buffalograss, Terrance P. Riordan, Susan De Shazer Steele, Milton C. Engelke, Leonard A. Wit Jr., Frederick P. Baxendale, Jeana L. F. Svoboda, Jennifer M. Johnson-Cicalese, Edward J. Kinbacher

Department of Entomology: Faculty Publications

A vegetatively reproduced buffalograss cultivar, named 315 Buffalograss, is distinguished by its excellent dark green color, high density, low growth habit, drought resistance, heat and cold tolerance, wear tolerance, low maintenance requirements and slow rate of establishment.

Effects Of Alachlor On An Algal Community From A Midwestern Agricultural Stream, Rebecca Spawn, Kyle D. Hoagland, Blair Siegfried

Department of Entomology: Faculty Publications

The effects of a single pulse, 21-d exposure of the commonly used herbicide alachlor (2-chloro-2′, 6′-diethyl-N-methoxymethyl acetanilide) on an algal community from a typical agricultural stream in Nebraska were studied using 18 stream microcosms located in a greenhouse, at six alachlor concentrations (0, 1, 10, 30, 100, and 1,000 μg/L). Effects of alachlor exposure at 1.0 μg/L were not significant (p < 0.05); however, at all other concentrations, alachlor had a significant negative effect on algal biomass. Differential taxonomic responses were observed, with approximately half the dominant algal taxa affected at levels >10 μg/L. Some taxa recovered from exposure by day 7, while others took longer or did not recover. A shift in the dominant algae was observed at higher concentrations (30, 100, 1,000 μg/L), and after 21 d these streams …

Pest Management Practices Of Crop Consultants In The Midwestern Usa, Robert Wright, Terry A. Devries, Shripat T. Kamble

Department of Entomology: Faculty Publications

A mail survey was conducted of independent crop consultants in 12 midwestern U.S. states working in corn (Zea mays L.), soybeans [Glycine max (L.) Merrill], wheat (Triticum aestivum L.), and grain sorghum (Sorghum bicolor L. Moench.) during 1993. The survey was conducted to document the acreage of crops monitored by crop consultants, and some of their operational characteristics. Kansas and Nebraska had the greatest reported acreage of crops scouted, over 3 million and 1 million acres, respectively. Total acres scouted were highest for corn, followed by soybeans, wheat, alfalfa (Medlcago sativa L.), and sorghum. Acres …

Bt Corn And European Corn Borer, K. R. Ostlie, W. D. Hutchison, R. L. Hellmich

Department of Entomology: Faculty Publications

Authors and Contributors: J.F. Witkowski, J.L. Wedberg, K.L. Steffey, P.E. Sloderbeck, B.D. Siegfried, M.E. Rice, C.D. Pilcher, D.W. Onstad, C.E. Mason, L.C. Lewis, D.A. Landis, A.J. Keaster, F. Huang, R.A. Higgins, M.J. Haas, M.E. Gray, K.L. Giles, J.E. Foster, P.M. Davis, D.D. Calvin, L.L. Buschman, P.C. Bolin, B.D. Barry, D.A. Andow & D.N. Alstad.

Bt Corn & European Corn Borer

Seed companies are now marketing Bt corn, one of the first tangible fruits of biotechnology that has practical implications for U.S. and Canadian corn farmers. Bt corn hybrids produce an insecticidal protein derived from the bacterium Bacillus thuringiensis, commonly called …

Seasonal Occurrence Of Rice Yellow Mottle Virus In Lowland Rice In Côte D’Ivoire, E. A. Heinrichs, A. A. Sy, S. K. Akator, I. Oyediran

Department of Entomology: Faculty Publications

Monthly plantings of the rice variety Bouaké 189 were made under lowland irrigated conditions, to obtain information on the phenological and seasonal occurrence of pests and diseases on the West African Rice Development Association (WARDA) research farm near Bouaké, Côte d’Ivoire. Regular sampling of insect pests and observations on rice yellow mottle virus (RYMV) disease infection throughout the year provided information on the occurrence of RYMV and potential insect vectors. RYMV incidence and grain yields varied depending on planting date, and for a given planting date, varied from one year to another. There was no evidence that RYMV incidence increases …

Mitochondrial Dna Variation Among Muscidifurax Spp. (Hymenoptera: Pteromalidae), Pupal Parasitoids Of Filth Flies (Diptera), David B. Taylor, Richard D. Peterson Ii, Allen L. Szalanski, James J. Petersen

Department of Entomology: Faculty Publications

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing analyses were used to characterize an amplicon of ~625 bp in 4 of the 5 nominate species of Muscidifurax Girault & Sanders, pupal parasitoids of muscoid flies. A single polymorphic nucleotide site was observed among 2 samples of M. raptor Girault & Sanders. No sequence variation was observed among 3 samples of M. raptorellus Kogan & Legner. The sequence of M. uniraptor Kogan & Legner was identical to that of M. raptorellus. Nucleotide divergence among the Muscidifurax spp. ranged from 0.14 to 0.18 substitutions per nucleotide. Muscidifurax zaraptor Kogan & …