Agricultural Science Commons^™

Areawide Suppression Of Fire Ants, M. D. Aubuchon, R. K. Vander Meer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The imported fire ants, Solenopsis invicta and S. richteri, were inadvertently introduced into the USA in the early 1900s and currently inhabit over 129 million ha in Puerto Rico and 12 southern states, from Texas to Virginia (Callcott and Collins, 1996; USDA-APHIS map). Imported fire ants have also become established in isolated sites in California, Arizona, New Mexico and Maryland. Strict quarantine procedures have limited the spread of this pest (Lockley and Collins, 1990), but eventually populations will expand westward in increasing numbers in New Mexico, Arizona and California. They will also move upward along the Pacific coast, southward …

The Hawaii Fruit Fly Areawide Pest Management Programme, Roger I. Vargas, Ronald F. L. Mau, Eric B. Jang, Robert M. Faust, Lyle Wong

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fruit flies (Diptera: Tephritidae) are among the most economically important pests attacking soft fruits worldwide (White and Elson-Harris, 1992). Four invasive species Mediterranean fruit fly or medfly (Ceratitis capitata), melon fly (Bactrocera cucurbitae), oriental fruit fly (Bactrocera dorsalis) and the so-called Malaysian fruit fly or solanaceous fruit fly (Bactrocera latifrons) - have been devastating to Hawaiian agriculture for over 100 years by infesting more than 400 different host plants. These fruit flies:

• Jeopardize development of a diversified tropical fruit and vegetable industry.

• Require that commercial fruits undergo quarantine treatment prior …

Short Communication- An Update On The Diversity Of Wolbachia In Spalangia Spp. (Hymenoptera: Pteromalidae), K.D. Floate, P.C. Coghlin, D. B. Taylor

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Results from 13 additional host populations improves resolution on the diversity of Wolbachia bacteria in Spalangia spp. (Hymenoptera: Pteromalidae). These bacteria are of interest because they can profoundly affect their host’s reproduction. Manipulating Wolbachia infections may provide a method to improve the efficacy of biocontrol agents including Spalangia spp.

Parasitoid wasps (Pteromalidae: Hymenoptera) are of interest as biocontrol agents for pest flies (Diptera: Muscidae) of livestock confinements; e.g. dairies, cattle feedlots, poultry houses, swine barns. Many of these wasps are infected with Wolbachia bacteria that can profoundly affect their host’s reproduction. Wolbachia induce parthenogenesis in Muscidifurax uniraptor Kogan & Legner …

Aged Switchgrass Seed Lot's Response To Dormancy-Breaking Chemicals, Gautam Sarath, Robert B. Mitchell

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Aged switchgrass seed lots can display various levels of dormancy. Under-standing the causes for this dormancy will provide better insight into seed physiology, and potentially lead to treatments that reduce variability in seed germination assays. The effects of sodium nitroprusside, potassium ferro-cyanide and hydrogen peroxide on the germination of eight aged switch-grass (Panicum virgatum L.) seed lots, seven of which were produced in the same year at a single experiment station, were examined. Seed germination demonstrated a significant seed lots × days and treatments × days effect. However, responses of individual seed lots to specific chemicals varied considerably. Genetically …

Screwworms, Cochliomyia Hominivorax, Reared For Mass Release Do Not Carry And Spread Foot-And-Mouth Disease Virus And Classical Swine Fever Virus, M. F. Chaudhury, G. B. Ward, Steven R. Skoda, M. Y. Deng, J. B. Welch, T. S. Mckenna

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Experiments were done to determine if transporting live screwworms Cochliomyia hominivorax Coquerel (Diptera: Calliphoridae) for developing new strains from countries where foot-and-mouth disease and classical swine fever are endemic, to the mass rearing facilities in Mexico and Panama, may introduce these exotic diseases into these countries. Are screwworms capable of harboring and spreading foot-and-mouth disease virus (FMDV) and classical swine fever virus (CSFV) when they are grown in virus-inoculated larval rearing medium? In one experiment, screwworm larvae were reared in a FMDV-inoculated artificial medium containing either 0.1% formaldehyde. In each experiment, samples of larvae and the rearing media were collected …

Volatile Compounds From The Integument Of White Leghorn Chickens (Gallus Gallus Domesticus L.): Candidate Attractants Of Ornithophilic Mosquito Species, Ulrich R. Bernier, Sandra A. Allan, Brian Quinn, Daniel Kline, Donald Barnard, Gary Clark

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Candidate kairomones of ornithophilic mosquito species are reported from GC/MS analysis of compounds from the skin on the back, the feet, and feathers from the back of White Leghorn chickens (Gallus gallus domesticus). Hexane and ether extracts of chicken feathers differ significantly in attractiveness of Culex spp. mosquitoes. The active (hexane) extracts contained an abundance of alcohols, ketones, and diones. The inactive (ether) extracts contained aldehydes, which also were in the hexane extracts. Analysis of hexane extracts from chicken feet, skin, and feathers demonstrated the qualitative similarity in the compounds collected with subtle differences observed in the quantitative …

Assessing Yield Potential Of Cowpea Genotypes Grown Under Virus Pressure, Ricardo Goenaga, Adolfo Quiles, A. Graves Gillaspie

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Cowpea or Southernpea [Vigna unguiculata (L.) Walp.] is an important grain legume in many parts of the tropics. However, viral diseases, particularly Cucumber mosaic virus (CMV) and Blackeye cowpea mosaic virus (BlCMV), can be a limiting factor in cowpea production. We evaluated in replicated field plots and under virus pressure nine PIs (441919, 441925, 441917, 147071, 146618, 180014, 180355, 194208, 612607) and three commercial cultivars (Coronet, KnuckleHull-VNR, Pinkeye Purplehull), some of which had shown absence of symptoms for CMV and BlCMV in unreplicated, seed regeneration plots of the U.S. cowpea collection. Only 3% of all plots had plants infected …

Discovery Of Diurnal Resting Sites Of Phlebotomine Sand Flies In A Village In Southern Egypt, Jerome Hogsette, Hanafi A. Hanafi, Ulrich R. Bernier, Daniel L. Kline, Emad Y. Fawaz, Barry D. Furman, David F. Hoel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In an attempt to find diurnal resting sites of adult phlebotomine sand flies, potential phlebotomine adult habitats were aspirated in the village of Bahrif in Aswan, Egypt. During this survey, sand flies were aspirated from low (30–45 cm high) irregular piles of mud bricks found under high date palm canopies between the village and the Nile River. There were 5 ♂♂and 7 ♀♀ of Phlebotomus papatasi and 3♂♂ of Sergentomyia schwetzi. Six of the 7 aspirated females were engorged with blood. A total of 78 sand flies was captured on 3 glue boards placed overnight on the ground next …

Enteric Bacteria Of Field-Collected Colorado Potato Beetle Larvae Inhibit Growth Of The Entomopathogens Photorhabdus Temperata And Beauveria Bassiana, Michael B. Blackburn, Dawn E. Gundersen-Rindal, Donald C. Weber, Phyllis A. W. Martin, Robert R. Farrar Jr.

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The nematode Heterorhabditis marelatus fails to reproduce in the Colorado potato beetle, Leptinotarsa decemlineata, possibly due to interference from the enteric bacteria of the beetle. Specifically, the enteric bacteria inhibit the growth of Photorhabdus temperata, the enteric symbiont of the nematode, in vitro. However, previous work was based on a laboratory culture of L. decemlineata, and we wished to determine if similar bacteria were present in the field. Therefore, we cultured the enteric bacteria of fourth-instar larvae collected from the field at two locations in Maryland and Virginia. Representatives of the genera Pantoea, Enterobacter, Pseudomonas …

Improvement Of Pvx/Cmv Cp Expression Tool For Display Of Short Foreign Antigens, Angela Natilla, Lev G. Nemchinov

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

We have previously reported that Potato virus X-expressed coat protein of Cucumber mosaic virus (CMV) formed virus-like particles (VLPs), which served as carriers for display of different neutralizing epitopes of Newcastle disease virus (NDV). In this work, we further modified the purification protocol of recombinant VLPs carrying short neutralizing epitopes of the NDV proteins and demonstrated that self-contained capsid protein subunits of CMV transiently expressed from heterologous virus packaged into individual virions morphologically resembling and/or indistinguishable from wild type CMV particles. Homogeneity of the final preparation represents an advance over our previous study, where VLPs were found to be of …

The Genetic Diversity, Relationships, And Potential For Biological Control Of The Lobate Lac Scale, Paratachardina Pseudolobata Kondo & Gullan (Hemiptera: Coccoidea: Kerriidae), S. Schroer, R. W. Pemberton, L. G. Cook, T. Kondo, P. J. Gullan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The lobate lac scale Paratachardina pseudolobata Kondo & Gullan (Kerriidae) is a polyphagous pest of woody plants in Florida (U.S.A.) the Bahamas, Christmas Island (Australia) and it has been reported from Cuba. Its recent appearance as a pest in these places indicates that this scale is introduced; however, its native range is unknown. Until 2006, this pest species was identified mistakenly as Paratachardina lobata (Chamberlin) [now P. silvestri (Mahdihassan)], which is native to India and Sri Lanka. Quarantine laboratory acceptance trials with Indian P. silvestri parasitoids indicated a strong immune response from P. pseudolobata. Gregarious development of encyrtid wasps …

A Core Set Of Microsatellite Markers For Western Corn Rootworm (Coleoptera: Chrysomelidae) Population Genetics Studies, Kyung Seok Kim, Uwe Stolz, Nicholas J. Miller, Miller R. Waits, Thomas Guillermaud, Douglas V. Sumerford, Thomas W. Sappington

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Interest in the ecological and population genetics of the western corn rootworm, Diabrotica virgifera virgifera LeConte, has grown rapidly in the last few years in North America and Europe. This interest is a result of a number of converging issues related to the increasing difficulty in managing this pest and the need to characterize and understand gene ßow in the context of insect resistance management. One of the key components needed for successful population genetics studies is the availability of suitable molecular markers. Using a standard group of microsatellite markers enables researchers from different laboratories to directly compare and share …

Entomopathogenic Fungal Endophytes, Fernando E. Vega, Francisco Posada, M. Catherine Aime, Monica Pava-Ripoll, Francisco Infante, Stephen A. Rehner

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fungal endophytes are quite common in nature and some of them have been shown to have adverse effects against insects, nematodes, and plant pathogens.
Our research program is aimed at using fungal endophytes-mediated plant defense as a novel biological control mechanism against the coffee berry borer, the most devastating pest of coffee throughout the world. A survey of fungal endophytes in coffee plants from Hawaii, Colombia, Mexico, and Puerto Rico has revealed the presence of various genera of fungal entomopathogens, including Acremonium, Beauveria, Cladosporium, Clonostachys, and Paecilomyces. Two of these, B. bassiana and Clonostachys rosea …

Prevalence Of The Prion Protein Gene E211k Variant In U.S. Cattle, Michael P Heaton, John W. Keele, Gregory P. Harhay, Jürgen A. Richt, Mohammad Koohmaraie, Tommy L. Wheeler, Steven D. Shackelford, Eduardo Casas, D. Andy King, Tad S. Sonstegard, Curtis P. Van Tassell, Holly L. Neibergs, Chad C. Chase Jr., Theodore S. Kalbfleisch, Timothy Smith, Michael L. Clawson, William W. Laegreid

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: In 2006, an atypical U.S. case of bovine spongiform encephalopathy (BSE) was discovered in Alabama and later reported to be polymorphic for glutamate (E) and lysine (K) codons at position 211 in the bovine prion protein gene (Prnp) coding sequence. A bovine E211K mutation is important because it is analogous to the most common pathogenic mutation in humans (E200K) which causes hereditary Creutzfeldt – Jakob disease, an autosomal dominant form of prion disease. The present report describes a high-throughput matrix-associated laser desorption/ionization-time-of-flight mass spectrometry assay for scoring the Prnp E211K variant and its use to determine an upper limit …

Case Study Of Multiyear Precipitation Variations And The Hydrology Of Fort Cobb Reservoir, Jurgen D. Garbrecht, Jeanne M. Schneider

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Impacts of decadal precipitation variations on reservoir inflow, flood releases, and pool elevation were investigated for the Fort Cobb Reservoir, which controls runoff from a 787 km² agricultural watershed in central Oklahoma. The difference in mean annual precipitation between multiyear dry and wet periods was 33% of the long-term mean and led to a corresponding 100% change in mean reservoir inflow, 170% change in mean annual flood releases from the reservoir, and a maximum drop in conservation pool elevation of 2 m. From a reservoir operations perspective, only the frequency of controlled flood releases was impacted by decadal precipitation …

Codling Moth Areawide Integrated Pest Management, Alan L. Knight

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Codling moth (CM) is an insidious pest, tunnelling to the core of valuable commodities that are typically marketed with exceptional quality standards for appearance, firmness and sweetness. While there is no mention in the Bible of whether the apple that Eve gave to Adam graded 'Extra fancy', it is likely that if this fruit had been infested with CM, the human race would not be as anxious about returning to a pest-ridden garden of paradise. Nevertheless, since Noah allowed two adult CM to disembark from his boat, the distribution of this pest has closely followed man's cultivation of its hosts …

Stored-Grain Insect Areawide Pest Management, David W. Hagstrum, Paul W. Flinn, Carl R. Reed, Thomas W. Phillips

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Wheat is harvested in the USA from June in the southern part of the wheat-growing region until August in the northern part (Ragstrum and Reid, 1988). Grain temperature, grain moisture and storage time are the main factors determining the risk of economic losses from insect infestation. Wheat harvested in June in southern regions is generally at higher risk because grain temperature is suitable for insect movement and reproduction for a longer time than is wheat harvested in August in northern regions. Currently, management of insect pests in the wheat marketing system is usually sufficiently effective to slow insect population growth …

Impact Of Solar Ultraviolet-B On The Proteome In Soybean Lines Differing In Flavonoid Contents, Chenping Xu, Joe H. Sullivan, Wesley M. Garrett, Thomas J. Caperna, Savithiry Natarajan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) was used to systematically investigate the impact of solar ultraviolet- B (UV-B) radiation on the soybean leaf proteome. In order to investigate the protective role of flavonoids against UV-B, two isolines of the Clark cultivar (the standard line with moderate levels of flavonoids and the magenta line with reduced flavonoids) were grown in the field with or without natural levels of UV-B. The 12-day-old first trifoliates were harvested for proteomic analysis. More than 300 protein spots were reproducibly resolved and detected on each gel. Statistical analysis showed that 67 protein spots were significantly (P < 0.05) affected by solar UV-B. Many more spots were altered by UV-B in the magenta line than in the standard line. Another 12 protein spots were not altered by UV-B but showed significantly (P < 0.05) different accumulations between the two lines, and for most spots the line-specific differences were also observed under UV-B exclusion. Most of the differentially accumulated spots were identified by mass spectrometry. The proteins were quite diverse, and were involved in metabolism, energy, protein destination/storage, protein synthesis, disease/defense, transcription, and secondary metabolism. The results suggest that high levels of flavonoids lead to a reduction in UV-B sensitivity at the proteomic level.

Phylogenetic Relationships And Genetic Diversity Of The Usda Vigna Germplasm Collection Revealed By Gene-Derived Markers And Sequencing, Ming Li Wang, Noelle Barkley, Graves Gillaspie, Gary A. Pederson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Phylogenetic relationships in the USDA Vigna germplasm collection are somewhat unclear and their genetic diversity has not been measured empirically. To reveal interspecific phylogenetic relationships and assess their genetic diversity, 48 accessions representing 12 Vigna species were selected, and 30 gene-derived markers from legumes were employed. Some high-quality amplicons were sequenced. Indels (insertion/deletions) were discovered from the sequence alignments that were specific identifiers for some Vigna species. With regard to revealing polymorphisms, intron-spanning markers were more effective than exon-derived markers. These gene-derived markers were more successful in revealing interspecific polymorphisms than intraspecific polymorphisms at both the DNA fragment and sequence …

Pollen From The Exoskeletons Of Stable Flies, Stomoxys Calcitrans (Linnaeus 1758), In Gainesville, Florida, U.S.A., David M. Jarzen, Jerome Hogsette

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Stable flies are an important pest of humans and livestock. Despite being blood feeders, they also visit flowers to eat nectar. Stable flies with pollen adhering to their exoskeletons were collected at the University of Florida Horse Teaching Unit and taken to the Paleobotany and Palynology Laboratory at the Florida Museum of Natural History for processing and identification. The pollen on all the specimens was identified as Carolina willow, Salix caroliniana Michaux 1803. This small shrub or tree is found throughout Florida in wetland areas. This study demonstrates the utility of pollen analysis in interdisciplinary studies.

Biotinyl-Methyl 4-(Amidomethyl)Benzoate Is A Competitive Inhibitor Of Human Biotinidase, Keyna Kobza, Kittichai Chaiseeda, Gautam Sarath, James M. Takacs, Janos Zempleni

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Posttranslational modification of histones by biotinylation can be catalyzed by both biotinidase (BTD) and holocarboxylase synthetase. Biotinylation of histones is an important epigenetic mechanism to regulate gene expression, DNA repair, and chromatin remodeling. The role of BTD in histone biotinylation is somewhat ambiguous, given that BTD also catalyzes removal of the biotin tag from histones. Here, we sought to develop BTD inhibitors for future studies of the role of BTD in altering chromatin structure. We adopted an existing colorimetric BTD assay for use in a novel 96-well plate format to permit high-throughput screening of potential inhibitors. Biotin analogs were chemically …

Comparison Of Corn And Switchgrass On Marginal Soils For Bioenergy, Gary E. Varvel, Kenneth P. Vogel, Robert B. Mitchell, R. F. Follett, J. M. Kimble

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Crop residues such as corn (Zea mays L.) stover are viewed as an abundant and inexpensive source of biomass that can be removed from fields to produce bioenergy. Assumptions revised form include that with minimum or no-tillage farming methods, there will be no deleterious production or environmental effects. A long-term field study was established in eastern Nebraska, USA, to compare the switchgrass managed as a biomass energy crop versus no-till corn on a non-irrigated site, marginal for row-crop production, in the western Corn Belt. Our objective in this paper is to report on corn stover removal effects on corn …

Chapter 19. Remediation Of Drinking Water For Rural Populations, W. J. Hunter

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Nitrate is the most common nitrogen contaminant in raw water supplies. In rural areas agricultural activities that involve the use of fertilizers and animal manures are major sources of nitrate contamination. Several processes are currently available that can effectively remove nitrate from raw water. Systems that are suitable for small rural communities include reverse osmosis, ion exchange, and electrodialysis. However, all of these systems move nitrate from raw water and concentrate it in a reject water or brine. Disposal of the reject water can be a major expense as well as an environmental issue. Several emerging systems are under development …

Auditing And Assessing Air Quality In Concentrated Feeding Operations, N. A. Cole, R. Todd, B. Auvermann, D. B. Parker

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The potential adverse effects of concentrated animal feeding operations (CAFO) on the environment are a growing concern. The air quality issues of most concern to CAFO vary but generally include ammonia, hydrogen sulfide, particulate matter, volatile organic compounds, greenhouse gases, and odors. Air pollutants may be regulated by federal and state laws or by nuisance complaints. The United States Environmental Protection Agency, and poultry, swine, and dairy industries recently agreed to the National Air Emissions Monitoring System to fund research on atmospheric emissions from production farms in the United States. Air quality regulations may be based on actual emissions, atmospheric …

Evaluation Of Beef Cattle Operations Utilizing Different Seasons Of Calving, Weaning Strategies, Postweaning Management, And Retained Ownership, R. E. Kruse, M. W. Tess, E. E. Grings, R. E. Short, R. K. Heitschmidt, W. A. Phillips, H. S. Mayeux

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Data from a 3-yr study in Montana were utilized to evaluate impacts of season of calving, weaning strategy, and retained ownership of steer calves on enterprise profitability. Calving seasons were late winter (LW), early spring (ES), or late spring (LS). Each season had 2 weaning times: 190 (LW190, ES190) or 240 (LW240, ES240) d for LW and ES, and 140 (LS140) or 190 (LS190) d for LS. Backgrounding options included shipping steers to Oklahoma (OK1), or backgrounding in Montana to a constant age (MT2) or weight (MT3). Steers from OK1 and MT2 were finished in Oklahoma in confinement or via …

Physiological Aging Of Potato Tubers Produced During Fall And Spring Growing Seasons And Stored Under Different Temperatures, Dilson A. Bisognin, Sergio T. De Freitas, Auri Brackmann, Jeronimo Luiz Andriolo, Engil Isadora Pujol Pereira, Douglas Renator Muller, Mauricio Guerra Bandinelli

School of Earth, Environmental, & Marine Sciences Faculty Publications

Adequate tuber storage is necessary to maintain a good availability of potato tubers in the market and to get seeds with adequate physiological age at planting. The objective of this work was to determine the effect of different storage temperatures on tuber physiological aging of three potato clones produced during fall and spring growing seasons. The experiment was carried out as factorial of three clones (Asterix, SMIJ461-1 and SMINIA793101-3) by four storage temperatures (4, 8, 12 and 25 ºC) and two growing seasons (fall and spring) in a random design with four replications. At 30-day intervals, tubers were evaluated from …

Potential Of Sequential Cropping In The Management Of Root-Knot Nematodes In Okra, A. N. Mweke, J. W. Kimenju, A. A. Seif, E. W. Mutitu, G. K. Mutua

All Peer-Reviewed Publications

The response of different crops to a mixed population of root-knot nematodes, Meloidogyne javanica and M. incognita and their potential as suppressants in sequential cropping systems was evaluated in greenhouse and field experiments. Crops rated as resistant were five maize cultivars, four sorghum cultivars, two millet varieties, guwar and two pigeonpea cultivars which had galling indices ranging between 1.4-3.6. cowpea cv. K80 was rated as moderately resistant with a galling index of 4 while greengram and cowpea cv. KKI were rated as susceptible with galling indices ranging from 5.6 to 7.4. Four crops namely sweetcorn, babycorn, maize cv. Pioneer (Ph3253) …