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Upic: Perl Scripts To Determine The Number Of Ssr Markers To Run, R. S. Arias, Linda L. Ballard, Brian E. Scheffler Jan 2009

Upic: Perl Scripts To Determine The Number Of Ssr Markers To Run, R. S. Arias, Linda L. Ballard, Brian E. Scheffler

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

We introduce here the concept of Unique Pattern Informative Combinations (UPIC), a decision tool for the cost-effective design of DNA fingerprinting/genotyping experiments using simple-sequence/tandem repeat (SSR/STR) markers. After the first screening of SSR-markers tested on a subset of DNA samples, the user can apply UPIC to find marker combinations that maximize the genetic information obtained by a minimum or desirable number of markers. This allows a cost-effective planning of future experiments. We have developed Perl scripts to calculate all possible subset combinations of SSR markers, and determine based on unique patterns or alleles, which combinations can discriminate among all DNA …


Efficiency And Establishment Of Three Introduced Parasitoids Of The Mealybug Paracoccus Marginatus (Hemiptera: Pseudococcidae), Kaushalya G. Amarasekare, Catharine M. Mannion, Nancy D. Epsky Jan 2009

Efficiency And Establishment Of Three Introduced Parasitoids Of The Mealybug Paracoccus Marginatus (Hemiptera: Pseudococcidae), Kaushalya G. Amarasekare, Catharine M. Mannion, Nancy D. Epsky

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

Three introduced parasitoids Acerophagus papayae, Anagyrus loecki, and Pseudleptomastix mexicana of the mealybug Paracoccus marginatus have been released in Miami-Dade and Broward counties (Florida) in 2003. Efficiency and establishment of these previously introduced parasitoids to control P. marginatus were measured in 2005 and 2006, at three locations in Homestead (Miami-Dade). Mealybug populations were initially established on three branches (per plant) of 10 hibiscus plants inside closed-sleeve cages. The three treatments, closed, open, and no-cage environments were applied to the three established mealybug populations on each plant. The number of mealybugs and natural enemies was monitored in all treatments. …


Host Range Of Tetramesa Romana Walker (Hymenoptera: Eurytomidae), A Potential Biological Control Of Giant Reed, Arundo Donax L. In North America, John A. Goolsby, Patrick Moran Jan 2009

Host Range Of Tetramesa Romana Walker (Hymenoptera: Eurytomidae), A Potential Biological Control Of Giant Reed, Arundo Donax L. In North America, John A. Goolsby, Patrick Moran

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

The eurytomid wasp, Tetramesa romana Walker was evaluated as a potential biological control agent of the invasive reed grass, Arundo donax in North America. No-choice tests and timed behavioral studies were used to determine the fundamental host range of two genotypes of the wasp collected from Granada, Spain and Perpignan, France. Thirty-five species, including two genotypes of A. donax and seven ecotypes of Phragmites australis, along with closely related grasses, economic grasses and habitat associates were tested. Complete development of both T. romana genotypes was restricted to A. donax and Arundo formosana. The mean number of offspring produced …


Flight Phenology Of Male Cactoblastis Cactorum (Lepidoptera: Pyralidae) At Different Latitudes In The Southeastern United States, Stephen D. Hight, James E. Carpenter Jan 2009

Flight Phenology Of Male Cactoblastis Cactorum (Lepidoptera: Pyralidae) At Different Latitudes In The Southeastern United States, Stephen D. Hight, James E. Carpenter

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

Long term trapping studies of the invasive moth Cactoblastis cactorum (Berg) were conducted at various latitudes from Puerto Rico to South Carolina. Three flight periods per year were identified at the 5 temperate sites studied, which covered the majority of the infested range on mainland United States. In general, the 3 flight periods across a latitudinal gradient from south Florida to central, coastal South Carolina were a spring flight during Feb-May, a summer flight during Jun-Aug, and a fall flight during Sep-Nov. At any 1 site, each flight period lasted about 2 months. In the tropical areas of the Florida …


Field Assessment Of Host Plant Specificity And Potential Effectiveness Of A Prospective Biological Control Agent, Aceria Salsolae, Of Russian Thistle, Salsola Tragus, Lincoln Smith, Massimo Cristofaro, Enrico De Lillo, Rosita Monfreda, Alessandra Paolini Jan 2009

Field Assessment Of Host Plant Specificity And Potential Effectiveness Of A Prospective Biological Control Agent, Aceria Salsolae, Of Russian Thistle, Salsola Tragus, Lincoln Smith, Massimo Cristofaro, Enrico De Lillo, Rosita Monfreda, Alessandra Paolini

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

The eriophyid mite, Aceria salsolae de Lillo and Sobhian, is being evaluated as a prospective classical biological control agent of invasive alien tumbleweeds, including Salsola tragus, S. collina, S. paulsenii and S. australis, in North America. Previous laboratory experiments to determine the host specificity of the mite indicated that it could sometimes persist and multiply on some nontarget plants, including Bassia hyssopifolia and B. scoparia. These are both European plants whose geographic range overlaps that of the mite, but the mite has never been observed on them in the field. A field experiment was conducted in …


Differential Induction Of Redox Sensitive Extracellular Phenolic Amides In Potato, C. Jacyn Baker, Bruce D. Whitaker, Norton M. Mock, Clifford P. Rice, Daniel P. Roberts, Kenneth L. Deahl, Peter P. Ueng, Andrey A. Aver’Yanov Jan 2009

Differential Induction Of Redox Sensitive Extracellular Phenolic Amides In Potato, C. Jacyn Baker, Bruce D. Whitaker, Norton M. Mock, Clifford P. Rice, Daniel P. Roberts, Kenneth L. Deahl, Peter P. Ueng, Andrey A. Aver’Yanov

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

This study focuses on the differential induction of extracellular phenolic amides that accumulate in potato cell suspensions during the first few hours of the interaction between these plant cells and either bacterial pathogens or pathogen-related elicitors. Using suspension cells of Solanum tuberosum we identified 4 hydroxycinnamic acid amides that accumulate in the extracellular environment. Treatment of the suspension cells with pathovars of the plant pathogens Pseudomonas syringae or Ralstonia solanacearum or with pathogen-related elicitors changed the composition of the extracellular phenolic amides within hours and the composition differed for each treatment. Some of the phenolic amides were sensitive to oxidative …


Where To Sample? Ecological Implications Of Sampling Strata In Determining Abundance And Impact Of Natural Enemies Of The Coffee Berry Borer, Hypothenemus Hampei, Juliana Jaramillo, Adenirin Chabi-Olaye, Christian Borgemeister, Charles Kamonjo, Hans-Michael Poehling, Fernando E. Vega Jan 2009

Where To Sample? Ecological Implications Of Sampling Strata In Determining Abundance And Impact Of Natural Enemies Of The Coffee Berry Borer, Hypothenemus Hampei, Juliana Jaramillo, Adenirin Chabi-Olaye, Christian Borgemeister, Charles Kamonjo, Hans-Michael Poehling, Fernando E. Vega

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

Several parasitoids of African origin have been introduced to coffee producing areas of the Americas and Asia as biological control agents of the coffee berry borer (CBB) Hypothenemus hampei (Coleoptera: Curculionidae). These parasitoids have become established in the field but their effect on the CBB has been limited. A two-year field study in Western Kenya has found Prorops nasuta (Hymenoptera: Bethylidae) to be the predominant parasitoid emerging from CBB-infested coffee berries collected on coffee trees or from the ground. P. nasuta comprises more than 75% of the total natural enemies collected. The density of P. nasuta was 90% higher in …


Root Responses Along A Subambient To Elevated Co2 Gradient In A C3–C4 Grassland, Laurel J. Anderson, Justin D. Derners, H. Wayne Polley, Wendy S. Gordon, David M. Eissenstat, Robert B. Jackson Jan 2009

Root Responses Along A Subambient To Elevated Co2 Gradient In A C3–C4 Grassland, Laurel J. Anderson, Justin D. Derners, H. Wayne Polley, Wendy S. Gordon, David M. Eissenstat, Robert B. Jackson

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

Atmospheric CO2 (Ca) concentration has increased significantly during the last 20 000 years, and is projected to double this century. Despite the importance of belowground processes in the global carbon cycle, community-level and single species root responses to rising Ca are not well understood. We measured net community root biomass over 3 years using ingrowth cores in a natural C3–C4 grassland exposed to a gradient of Ca from preglacial to future levels (230–550 µmol mol-1).


Nitrogen And Phosphorus Accumulation In Pasture Soil From Repeated Poultry Litter Application, Zhongqi He, C. Wayne Honeycutt, Irenus A. Tazisong, Zachary N. Senwo, Donglin Zhang Jan 2009

Nitrogen And Phosphorus Accumulation In Pasture Soil From Repeated Poultry Litter Application, Zhongqi He, C. Wayne Honeycutt, Irenus A. Tazisong, Zachary N. Senwo, Donglin Zhang

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

Poultry litter (PL) is a traditionally inexpensive and effective fertilizer to improve soil quality and agricultural productivity. However, over application to soil has raised concern because excess nutrients in runoff could accelerate the eutrophication of fresh water. In this work, we determined the contents of total phosphorus (P), Mehlich 3 extracted P, total nitrogen (N), ammonium (NH4)-N, and nitrate (NO3)-N, in pasture soils receiving annual poultry litter applications of 0, 2.27, 2.27, 3.63, and 1.36 Mg/ha/ yr, respectively, for 0, 5, 10, 15, and 20 years. Samples were collected from three soil depths (0–20, 20–40, and 40–60 cm) …


Plan To Support Grains Industry Development 2009-2012, Department Of Agriculture And Food, Western Australia Jan 2009

Plan To Support Grains Industry Development 2009-2012, Department Of Agriculture And Food, Western Australia

Grain and other field crops published reports

The Plan to Support Grains Industry Development (‘the Plan’) recognises that Western Australian agricultural industries are integral to the economic wellbeing of regional and rural communities. The Plan promotes a progressive and profitable grains industry through modern best practice services and research to enhance continuous improvement in farming and supply chain practices.

The Plan has been developed to align with the Government of Western Australia’s initiatives, strategies and tactics for ‘making every hectare count’ (see Appendix 1) and with grains industry needs as identified by industry stakeholders during a series of consultation forums. These industry needs will be addressed in …


Field Release Of A Non-Toxigenic Aspergillus Flavus L Strain In Central Benin, A. M. Klueken, C. Borgemeister, B. Hau Jan 2009

Field Release Of A Non-Toxigenic Aspergillus Flavus L Strain In Central Benin, A. M. Klueken, C. Borgemeister, B. Hau

All Peer-Reviewed Publications

Non-toxigenic strains of Aspergillus flavus (Link) can be used as biological control agents to reduce the contamination of grains such as maize with carcinogenic and immunotoxic aflatoxins. Based on its sclerotial morphology, A. flavus is commonly divided into two types: L strains and S strains. In this study, we applied the non-toxigenic A. flavus L strain BN030D to the soil of five maize fields in Djidja, central Benin, to investigate its effects on the composition of the prevailing fungal communities, on the ratio of A. flavus L strains and S strains, and on the vegetative compatibility of L strains with …


A High-Oleic-Acid And Low-Palmitic-Acid Soybean: Agronomic Performance And Evaluation As A Feedstock For Biodiesel, George L. Graef, Bradley J. Lavallee, Patrick Tenopir, Mustafa Tat, Bruce Schweiger, Anthony J. Kinney, Jon H. Van Gerpen, Thomas E. Clemente Dec 2008

A High-Oleic-Acid And Low-Palmitic-Acid Soybean: Agronomic Performance And Evaluation As A Feedstock For Biodiesel, George L. Graef, Bradley J. Lavallee, Patrick Tenopir, Mustafa Tat, Bruce Schweiger, Anthony J. Kinney, Jon H. Van Gerpen, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Phenotypic characterization of soybean event 335-13, which possesses oil with an increased oleic acid content (> 85%) and reduced palmitic acid content (< 5%), was conducted across multiple environments during 2004 and 2005. Under these conditions, the stability of the novel fatty acid profile of the oil was not influenced by environment. Importantly, the novel soybean event 335-13 was not compromised in yield in both irrigated and non-irrigated production schemes. Moreover, seed characteristics, including total oil and protein, as well as amino acid profile, were not altered as a result of the large shift in the fatty acid profile. The novel oil trait was inherited in a simple Mendelian fashion. The event 335-13 was also evaluated as a feedstock for biodiesel. Extruded oil from event 335-13 produced a biodiesel with improved cold flow and enhanced oxidative stability, two critical fuel parameters that can limit the utility of this renewable transportation fuel.


University Of Nebraska Selected To Manage The New Sorghum/Millet And Other Grains Crsp, John Yohe, Kimberly Christiansen Oct 2008

University Of Nebraska Selected To Manage The New Sorghum/Millet And Other Grains Crsp, John Yohe, Kimberly Christiansen

INTSORMIL Impacts and Bulletins

Dr. John Yohe, INTSORMIL CRSP Program Director, has announced that the University of Nebraska (UNL) has been selected as the Management Entity for the new Sorghum/Millet and Other Grains CRSP. The award was based on national competition among U. S. universities. This CRSP is funded through a Leader with Associates Cooperative Agreement instrument as opposed to a grant under which INTSORMIL was funded since 1979. The INTSORMIL CRSP, Managed by UNL in partnership with Kansas State University, Purdue University, Texas A&M University, UNL and West Texas A&M University, ends June 30, 2007. The Leader with Associates Cooperative Agreement is effective …


Summaries Of Arkansas Cotton Research 2007, Derrick M. Oosterhuis Oct 2008

Summaries Of Arkansas Cotton Research 2007, Derrick M. Oosterhuis

Arkansas Agricultural Experiment Station Research Series

No abstract provided.


Convergence Of Agriculture And Energy: Iii. Considerations In Biodiesel Production, Jon Van Gerpen, Allan Gray, Brent H. Shanks, Beth Calabotta, Drew Kershen, Alan Weber, Richard Joost, Todd A. Peterson Oct 2008

Convergence Of Agriculture And Energy: Iii. Considerations In Biodiesel Production, Jon Van Gerpen, Allan Gray, Brent H. Shanks, Beth Calabotta, Drew Kershen, Alan Weber, Richard Joost, Todd A. Peterson

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

Concern about rising prices and unstable sources of petroleum fuels is driving the search for U.S. domestically produced, renewable transportation fuels, such as biodiesel. Federal incentives of up to $1.10 per gallon have been supplemented by additional incentives and mandated biodiesel use in many states. The Renewable Fuel Standard in the Energy Independence and Security Act of 2007 requires the domestic use of 1 billion gallons of biomass-based diesel fuel by 2012, most of which likely will be biodiesel.
U.S. biodiesel production is primarily from soybean oil, but recent high prices have forced many producers to use lower-cost feedstocks such …


Intsormil Scientists Develop Insect Resistant Sorghum And Pearl Millet For Africa And The Usa, Intsormil Aug 2008

Intsormil Scientists Develop Insect Resistant Sorghum And Pearl Millet For Africa And The Usa, Intsormil

INTSORMIL Impacts and Bulletins

The aphids Melanaphis sacchari (sugarcane aphid) in Africa and Schizaphis graminum (greenbug, see above) in the United States; panicle bugs; sorghum midge, Stenodiplosis sorghicola; stalk borers and termites infest and reduce yields of sorghum. The millet head miner, Heliocheilus albipunctella, reduces grain yield and quality of pearl millet.

INTSORMIL entomologist Bonnie Pendleton, West Texas A&M University, collaborates with African scientists to develop management strategies for sorghum and millet insects. Emphasis is on developing plants resistant to pests. Hundreds of sorghum and pearl millet genotypes have been evaluated by INTSORMIL scientists for grain yield and quality and resistance to …


Pasteurellosis Transmission Risks Between Domestic And Wild Sheep, Michael W. Miller, Donald P. Knowles, Marie S. Bulgin, Billy R. Clay, Walter E. Cook, Subramaniam Srikumaran, A. David Scarfe, Dale Layfield Aug 2008

Pasteurellosis Transmission Risks Between Domestic And Wild Sheep, Michael W. Miller, Donald P. Knowles, Marie S. Bulgin, Billy R. Clay, Walter E. Cook, Subramaniam Srikumaran, A. David Scarfe, Dale Layfield

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

Disease has contributed significantly to the decline of bighorn sheep (Ovis Canadensis) populations throughout much of western North America, decreasing many native herds to less than 10% of their historical size and imperiling some populations and subspecies (Valdez and Krausman 1999). According to historical accounts (e.g., Grinnell 1928; Honess and Frost 1942; Shillinger 1937; Warren 1910), epidemics in some locations coincided with the advent of domestic livestock grazing in bighorn ranges, suggesting that novel pathogens may have been introduced into some bighorn populations beginning in the 1800s.
Native North American wild sheep species—bighorn sheep and thinhorn (Dall’s and …


The Potential For Crop-To-Wild Gene Flow In Sorghum In Ethiopia And Niger: A Geographic Survey, Tesfaye Tesso, Issoufou Kapran, Cecile Grenier, Allison Snow, Patricia Sweeney, Jeffrey F. Pedersen, David B. Marx, Gurling Bothma, Gebisa Ejeta Jul 2008

The Potential For Crop-To-Wild Gene Flow In Sorghum In Ethiopia And Niger: A Geographic Survey, Tesfaye Tesso, Issoufou Kapran, Cecile Grenier, Allison Snow, Patricia Sweeney, Jeffrey F. Pedersen, David B. Marx, Gurling Bothma, Gebisa Ejeta

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

Information about the potential for crop–wild hybridization is needed to understand how crop genes, including transgenes, affect the population genetics and ecology of sexually compatible relatives. Transgenic sorghum is under development for use by traditional farmers in Africa, the center of origin for sorghum [Sorghum bicolor (L.) Moench], but systematic surveys of the current extent of contact with wild and weedy relatives are lacking. We studied wild and weedy sorghums that are interfertile with the crop and constitute a crop–wild–weed complex. The survey was conducted in 2005 in areas of traditional sorghum cultivation in three regions of Ethiopia and …


In Vitro And In Vivo Techniques For Screening New Natural Product-Based Fungicides For Control Of Strawberry Anthracnose, Maritza Abril May 2008

In Vitro And In Vivo Techniques For Screening New Natural Product-Based Fungicides For Control Of Strawberry Anthracnose, Maritza Abril

Dissertations

Seven plant pathogenic fungi (Botrytis cinerea, Colletotrichum acutatum, C. fragariae, C. gloeosporioides, Fusarium oxysporum, Phomopsis obscurans, and P. viticola) valuable in screening fungicide efficacy were tested. Optimal and reproducible conditions for germination of these selected fungi were established by incorporating Roswell Park Memorial Institute 1640 (RPMI) as a medium of known composition and washing conidia to remove innate germination inhibitors. This step reduced average fungal germination times between 3.5 h and 21.2 h. The natural product-based fungicide, sampangine, seven sampangine analogs (4-bromo-sampangine, 4-methoxysampangine, benzo[4,5]sampangine, liriodenine Mel AMC-XIII-103, onychine, cryptolepine, and liriodenine CDH-II-37), plus seven conventional fungicides (benomyl, captan, cyprodinil, fenbuconazole, …


No-Till Corn After Bromegrass: Effect On Soil Carbon And Soil Aggregates, Ronald F. Follett, Gary E. Varvel, John M. Kimble, Kenneth P. Vogel Apr 2008

No-Till Corn After Bromegrass: Effect On Soil Carbon And Soil Aggregates, Ronald F. Follett, Gary E. Varvel, John M. Kimble, Kenneth P. Vogel

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

Grasslands in the Conservation Reserve Program (CRP) in the USA may be converted to grain crops for bioenergy. The effect of no-till conversion of a smooth bromegrass (Bromus inermis Leyss) grassland to no-till corn (Zea mays L.) production on soil organic carbon (SOC) in the western Corn Belt was monitored for over 6 yr. A different 13C/12C isotope signature is imparted to SOC by C4 plants including corn versus C3 plants such as bromegrass. Changes in C isotope ratios in SOC in three soil depths (0- to 5-, 5–10, and 10–30 cm) by particle size …


Testing A Simple Field Method For Assessing Nitrate Removal In Riparian Zones, Philippe Vidon, Michael G. Dosskey Apr 2008

Testing A Simple Field Method For Assessing Nitrate Removal In Riparian Zones, Philippe Vidon, Michael G. Dosskey

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

Being able to identify riparian sites that function better for nitrate removal from groundwater is critical to using efficiently the riparian zones for water quality management. For this purpose, managers need a method that is quick, inexpensive, and accurate enough to enable effective management decisions. This study assesses the precision and accuracy of a simple method using three ground water wells and one measurement date for determining nitrate removal characteristics of riparian buffer zones. The method is a scaled-down version of a complex field research method that consists of a large network of wells and piezometers monitored monthly for over …


Location, Acceptance And Suitability Of Lepidopteran Stemborers Feeding On A Cultivated And Wild Host-Plant To The Endoparasitoid Cotesia Flavipes Cameron (Hymenoptera: Braconidae), Meshack Obonyo, Fritz Schulthess, Juma Gerald, Onesmus Wanyama, Bruno Le Rü, Paul André Calatayud Apr 2008

Location, Acceptance And Suitability Of Lepidopteran Stemborers Feeding On A Cultivated And Wild Host-Plant To The Endoparasitoid Cotesia Flavipes Cameron (Hymenoptera: Braconidae), Meshack Obonyo, Fritz Schulthess, Juma Gerald, Onesmus Wanyama, Bruno Le Rü, Paul André Calatayud

All Peer-Reviewed Publications

Maize fields in Africa are usually surrounded by land occupied by wild plants many of which harbor lepidopteran stemborer species not found on crops. It is not known if the exotic braconid parasitoid Cotesia flavipes, which was released in Kenya in 1993 against the invasive crambid Chilo partellus, searches for and attacks these borers in their natural habitats and whether they are suitable for parasitoid development. The objective of this study was to assess the relationship between acceptance and suitability of six stemborer species attacking cultivated sorghum (C. partellus, Busseola fusca, Sesamia calamistis, and S. nonagrioides) or Napier grass (Busseola …


Adding Value To Swine Manure Through Accurate Prediction Of Organic Nitrogen Availability, Charles S. Wortman, Charles Shapiro, Aaron Nygren Mar 2008

Adding Value To Swine Manure Through Accurate Prediction Of Organic Nitrogen Availability, Charles S. Wortman, Charles Shapiro, Aaron Nygren

Department of Agronomy and Horticulture: Faculty Publications

Animal manure contains organic and inorganic nitrogen. The inorganic N, which is mostly ammonium-N but nitrate-N can be significant in composted manure, is typically considered to be 100% plant available if there are not significant losses, especially due to volatilization of ammonia-N. The availability of organic N, which is mostly from undigested and partially digested plant material needs to be mineralized to become plant available, is less predictable. Field research was conducted in eastern Nebraska to improve the basis for estimating organic N availability from injected or incorporated swine manure and from surface applied composted and stockpiled FM. The factors …


Spatiotemporal Dynamics Of Black-Tailed Prairie Dog Colonies Affected By Plague, David J. Augustine, Marc R. Matchett, Theodore P. Toombs, Jack F. Cully, Tommy L. Johnson, J. G. Sidle Mar 2008

Spatiotemporal Dynamics Of Black-Tailed Prairie Dog Colonies Affected By Plague, David J. Augustine, Marc R. Matchett, Theodore P. Toombs, Jack F. Cully, Tommy L. Johnson, J. G. Sidle

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

Black-tailed prairie dogs (Cynomys ludovicianus) are a key component of the disturbance regime in semi-arid grasslands of central North America. Many studies have compared community and ecosystem characteristics on prairie dog colonies to grasslands without prairie dogs, but little is known about landscape-scale patterns of disturbance that prairie dog colony complexes may impose on grasslands over long time periods. We examined spatiotemporal dynamics in two prairie dog colony complexes in southeastern Colorado (Comanche) and northcentral Montana (Phillips County) that have been strongly influenced by plague, and compared them to a complex unaffected by plague in northwestern Nebraska (Oglala). …


Release And Establishment Of Cotesia Flavipes For Biological Control Of Maize Stemborers In Zimbabwe, P. Chinwada, F. Schulthess, W. A. Overholt, P. Jowah, C. O. Omwega Mar 2008

Release And Establishment Of Cotesia Flavipes For Biological Control Of Maize Stemborers In Zimbabwe, P. Chinwada, F. Schulthess, W. A. Overholt, P. Jowah, C. O. Omwega

All Peer-Reviewed Publications

Five populations of the crambid stemborer Chilo partellus (Swinhoe) and one of the noctuid borer Busseola fusca (Fuller) from Zimbabwe were evaluated for their suitability for immature development of the exotic braconid larval parasitoid Cotesia flavipes Cameron. Successful parasitoid development occurred only on C. partellus but parasitism as well as egg-to-adult development time did not vary among the five populations. Smallest parasitoid broods, and sex ratios as the proportion of female offspring, however, were produced with C. partellus from the Muzarabani area of Zimbabwe. Co. flavipes became successfully established in five out of eight locations, where it had been released …


Effect Of Irrigation Amounts Applied With Subsurface Drip Irrigation On Corn Evapotranspiration, Yield, Water Use Efficiency, And Dry Matter Production In A Semiarid Climate, Jose O. Payero, David D. Tarkalson, Suat Irmak, Don Davison, James L. Petersen Feb 2008

Effect Of Irrigation Amounts Applied With Subsurface Drip Irrigation On Corn Evapotranspiration, Yield, Water Use Efficiency, And Dry Matter Production In A Semiarid Climate, Jose O. Payero, David D. Tarkalson, Suat Irmak, Don Davison, James L. Petersen

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

Quantifying the local crop response to irrigation is important for establishing adequate irrigation management strategies. This study evaluated the effect of irrigation applied with subsurface drip irrigation on field corn (Zea mays L.) evapotranspiration (ETc), yield, water use efficiencies (WUE = yield/ETc, and IWUE = yield/irrigation), and dry matter production in the semiarid climate of west central Nebraska. Eight treatments were imposed with irrigation amounts ranging from 53 to 356 mmin 2005 and from 22 to 226mmin 2006. A soil water balance approach (based on FAO-56) was used to estimate daily soil water and ETc. Treatments resulted in seasonal …


Geochemistry In The Modern Soil Survey Program, M. A. Wilson, R. Burt, J. M. Scheyer, A. B. Jenkins, J. V. Chiaretti, M. G. Ulmer Feb 2008

Geochemistry In The Modern Soil Survey Program, M. A. Wilson, R. Burt, J. M. Scheyer, A. B. Jenkins, J. V. Chiaretti, M. G. Ulmer

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

Elemental analysis has played an important role in the characterization of soils since inception of the soil survey in the US. Recent efforts in analysis of trace and major elements (geochemistry) have provided necessary data to soil survey users in a variety of areas. The first part of this paper provides a brief overview of elemental sources, forms, mobility, and bioavailability; critical aspects important to users of soil survey geochemical data for appropriate use and interpretations. Examples are provided based on data gathered as part of the US soil survey program. The second part addresses the organization of sample collection …


Responsive In-Season Nitrogen Management For Cereals, J.F. Shanahan, N. R. Kitchen, W. R. Raun, James S. Schepers Feb 2008

Responsive In-Season Nitrogen Management For Cereals, J.F. Shanahan, N. R. Kitchen, W. R. Raun, James S. Schepers

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

Current nitrogen (N) management strategies for worldwide cereal production systems are characterized by low N use efficiency (NUE), environmental contamination, and considerable ongoing debate regarding what can be done to improve N fertilizer management. Development of innovative strategies that improve NUE and minimize off-field losses is crucial to sustaining cereal-based farming. In this paper, we review the major managerial causes for low NUE, including (1) poor synchrony between fertilizer N and crop demand, (2) uniform field applications to spatially variable landscapes that commonly vary in crop N need, and (3) failure to account for temporally variable influences on crop N …


Opportunities And Roadblocks In Utilizing Forages And Small Grains For Liquid Fuels, Gautam Sarath, Robert B. Mitchell, S. E. Sattler, Deanna L. Funnell, Jeffrey F. Pedersen, Robert A. Graybosch, Kenneth P. Vogel Jan 2008

Opportunities And Roadblocks In Utilizing Forages And Small Grains For Liquid Fuels, Gautam Sarath, Robert B. Mitchell, S. E. Sattler, Deanna L. Funnell, Jeffrey F. Pedersen, Robert A. Graybosch, Kenneth P. Vogel

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

This review focuses on the potential advantages and disadvantages of forages such as switchgrass (Panicum virgatum), and two small grains: sorghum (Sorghum bicolor), and wheat (Triticum aesitvum), as feedstocks for biofuels. It highlights the synergy provided by applying what is known from forage digestibility and wheat and sorghum starch properties studies to the biofuels sector. Opportunities therefore, exist to improve biofuel qualities in these crops via genetics and agronomics. In contrast to cereal crops, switchgrass still retains tremendous exploitable genetic diversity, and can be specifically improved to Wt a particular agronomic, management, and conversion …


Mullewa Research Annexe Spring Field Day Future Farming Systems For North-Eastern Districts 21 August 2008, Department Of Agriculture, Western Australia Jan 2008

Mullewa Research Annexe Spring Field Day Future Farming Systems For North-Eastern Districts 21 August 2008, Department Of Agriculture, Western Australia

Grain and other field crops research reports

Papers:

  • Mullewa Research Annexe activities 2008

  • Wheat for today and the future

  • Consequences of strongly acidic and alkaline soils

  • Break crop influence on low rainfall heavy soil

  • Chemical fallow options for the north-east agricultural region

  • Herbicide tolerance of new wheat varieties

  • Lowrainfall oilseed crops for food and biofuel

  • Utilising stock to reduce business risk in Binnu! A case study