Agricultural Science Commons^™

Growth And Feed Efficiency Of Juvenile Channel Catfish Reared At Different Water Temperatures And Fed Diets Containing Various Levels Of Fish Meal, Menghe H. Li, Edwin H. Robinson, Brian C. Peterson, Terry D. Bates

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

Channel catfish Ictalurus punctatus do not feed well at low temperatures. It is generally thought that a diet containing fish meal enhances feed palatability at low temperatures since fish meal is highly palatable to fish. There is a lack of information on the effects of fish meal levels on the growth performance of channel catfish reared at low temperatures. Therefore, a study was conducted in a recirculating system to examine the effects of fish meal levels on the feed consumption, weight gain, and feed efficiency of juvenile channel catfish reared at various temperatures. Fish with an initial weight of 9.6 …

Water And Bromide Recovery In Wick And Pan Lysimeters Under Conventional And Zero Tillage, John P. Schmidt, Henry Lin

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

Quantifying in situ solute transport through soils and the landscape has been widely acknowledged as important and yet challenging. The objective of this study was to evaluate water and bromide movement in no-tilled (NT) and conventionally tilled (CT) corn using two different types of in situ lysimeters—pan and capillary wick— for single rainfall events. Four zero-tension pan and four capillary-wick lysimeters were installed 1.2 m deep on opposite sides of four soil pits. Two were under NT corn, and two were under CT corn. Bromide (Br) was either surface applied or applied with an initial 25 to 27 mm of …

Nationally Coordinated Evaluation Of Soil Nitrogen Mineralization Rate Using A Standardized Aerobic Incubation Protocol, T. S. Griffin, C. W. Honeycutt, S. L. Albrecht, K. R. Sistani, H. A. Torbert, B. J. Wienhold, B. L. Woodbury, R. K. Hubbard, J. M. Powell

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

Aerobic incubation methods have been widely used to assess soil nitrogen (N) mineralization, but standardized protocols are lacking. A single silt loam soil (Catlin silt loam; fine-silty, mixed, superactive, mesic, Oxyaquic Arguidoll) was subjected to aerobic incubation at six USDA-ARS locations using a standardized protocol. Incubations were conducted at multiple temperatures, which were combined based on degree days (DD). Soil water was maintained at 60% waterfilled pore space (WFPS; constant) or allowed to fluctuate between 60 and 30% WFPS (cycle). Soil subsamples were removed periodically and extracted in 2 M potassium chloride (KCl); nitrate (NO₃) and ammonium (NH …

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 …

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 …

Microbial Community Structure Dynamics In Ohio River Sediments During Reductive Dechlorination Of Pcbs, Andres Enrique Nunez

University of Kentucky Doctoral Dissertations

The entire stretch of the Ohio River is under fish consumption advisories due to contamination with polychlorinated biphenyls (PCBs). In this study, natural attenuation and biostimulation of PCBs and microbial communities responsible for PCB transformations were investigated in Ohio River sediments.

Natural attenuation of PCBs was negligible in sediments, which was likely attributed to low temperature conditions during most of the year, as well as low amounts of available nitrogen, phosphorus, and organic carbon. Moreover, surface sediments were relatively oxidized, as indicated by the prevalence of aerobic bacteria such as beta- Proteobacteria, alpha-Proteobacteria, Sphingobacteria, and Nitrospira in 16S rRNA sediment …

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) …

Winter Cover Crops And Vinegar For Early-Season Weed Control In Sustainable Cotton, P. J. Moran, S. M. Greenberg

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

Weeds may be suppressed by winter cover crops and the use of organic herbicides such as vinegar. Black oat (Avena strigosa) and hairy vetch (Vicia villosa) winter cover crops were planted for 2 years as part of a sustainable production system for cotton in the Lower Rio Grande Valley of Texas, and were till-killed each spring prior to cotton planting. Palmer amaranth (Amaranthus palmeri), common purslane (Portulaca oleracea), and sunflower (Helianthus annuus) were frequently-encountered winter and spring weeds. Both cover crops controlled winter weeds as well as did winter tillage …

A Landscape Perspective In Managing Vegetation For Beneficial Plant-Pestnatural Enemy Interactions: A Foundation For Areawide Pest Management, Michael J. Brewer, Takuji Noma, Norman C. Elliott

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

In the USA, Europe and increasingly in other regions, cropping systems designed for high production output are significant features of the landscape. Deployment of mechanized and high-input cropping systems over the last 50 years has resulted in substantial transformation and fragmentation of major grassland, shrubland and woodland systems throughout the world. These cropping systems are typically less diverse in species composition, structure and ecological functioning than those found in the original plant community (Altieri, 2004). Decreases in plant diversity of agroecosystems (i.e. the crops themselves and surrounding remnants of the original plant system) have negatively affected ecosystem functions (Freemark, 2005). …

Comparison Of Nitrogen Fertilization Methods And Rates For Subsurface Drip Irrigated Corn In The Semi-Arid Great Plains, D. D. Tarkalson, J. O. Payero

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

In semi‐arid areas such as western Nebraska, interest in subsurface drip irrigation (SDI) for corn is increasing due to restricted irrigation allocations. However, crop response quantification to nitrogen (N) applications with SDI and the environmental benefits of multiple in‐season (IS) SDI N applications instead of a single early‐season (ES) surface application are lacking. The study was conducted in 2004, 2005, and 2006 at the University of Nebraska‐Lincoln West Central Research and Extension Center in North Platte, Nebraska, comparing two N application methods (IS and ES) and three N rates (128, 186, and 278 kg N ha^-1) using a …

Synthesis And Bioassay Of Improved Mosquito Repellents Predicted From Chemical Structure, Alan R. Katritzky, Zuoquan Wang, Svetoslav Slavov, Maia Tsikolia, Dimitar Dobchev, Novruz G. Akhmedov, C. Dennis Hall, Ulrich R. Bernier, Gary G. Clark, Kenneth Linthicum

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

Mosquito repellency data on acylpiperidines derived from the United States Department of Agriculture archives were modeled by using molecular descriptors calculated by CODESSA PRO software. An artificial neural network model was developed for the correlation of these archival results and used to predict the repellent activity of novel compounds of similar structures. A series of 34 promising N-acylpiperidine mosquito repellent candidates (4a–4q’) were synthesized by reactions of acylbenzotriazoles 2a–2p with piperidines 3a–3f. Compounds (4a–4q’) were screened as topically applied mosquito repellents by measuring the duration of repellency after application to cloth patches worn on the arms of human volunteers. Some …

Using The Solvent Retention Capacity Test When Breeding Wheat For Diverse Production Environments, Carl Walker, Kimberly A. Garland-Campbell, Brady Carter, Kimberlee Kidwell

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

The solvent retention capacity (SRC) test is used to predict commercial baking performance of soft wheat (Triticum aestivum L.) by measuring the capacity of flour to retain each of four solvents— water, Na₂CO₃, sucrose, and lactic acid— to assess overall absorption capacity, starch damage, pentosan and gliadin content, and glutenin quality, respectively. Our objectives were to determine sources of variation in the test, repeatability, and optimum scale and resource allocation needed to maximize efficiency. Duplicate SRC tests were conducted for each solvent using two flour sample sizes (5 and 0.2 g) from two field replications …

Registration Of ‘Darrell’ Wheat, A. M. H. Ibrahim, S. D. Haley, P. S. Baenziger, Y. Jin, M. A. C. Langham, J. Rickertsen, S. Kalsbeck, R. Little, J. Ingemansen, O. K. Chung, B. W. Seabourn, G. H. Bai, Ming-Shun Chen, D. V. Mcvey

Department of Agronomy and Horticulture: Faculty Publications

‘Darrell’ (Reg. No. CV-1024, PI 644224) hard red winter wheat (Triticum aestivum L.) was developed by the South Dakota State University–Agricultural Experiment Station and released in 2006 to seed producers by the South Dakota State University–Agricultural Experiment Station and the University of Nebraska Agricultural Experiment Station. Darrell was selected from the cross 2076-W12-11/‘Karl 92’ (PI 564245)//NE89526. NE89526 is an experimental line from the University of Nebraska with the pedigree ‘Lancota’ (CI 17389) selection/’Siouxland’ (PI 483469)//TX792729. 2076-W12-11 is an unreleased experimental line that originated from a population with an unidentified pedigree. Darrell was selected as an F3:4 line in 1998 …

Pastoral Profits Guide, A Paddock Guide To Achieving Sustainable Livestock Productivity, Mark Alchin, Jim Addison, Valarie Shrubb, Zac Cockerill, Matthew Young, Tim Johnson, Greg Brennan

All other publications

Most pastoralists appreciate the need to deliver an economic, environmental and social 'profit' from their business. Achieving these profits can be a real challenge given the comparatively low productive potential and the substantial seasonal variation in the WA Southern Rangelands region. This guide was written to assist pastoralists to meet their specific livestock production, financial and range condition objectives through the better alignment of feed demand (stocking rate) to feed supply (carrying capacity). We provide nine basic steps that simplify the process of managing the feed supply, equipping pastoralists with the tools to make· decisions and to critically assess the …