Agricultural Science Commons^™

Evaluation Of 41 Elite And Exotic Inbred Sorghum Genotypes For High Quality Callus Production, Heidi F. Kaeppler, Jeffrey F. Pedersen

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

Interest is high in the genetic study and improvement of sorghum(Sorghum bicolor L. Moench), a crop of worldwide agronomic importance. The ability to initiate and maintain high quality (pigmentless, mucilage-free, fast growing, type II) callus cultures from a variety of sorghum genotypes is important for certain tissue culture-based genetic studies. The objective of this study was to identify high-quality callus-producing genotypes from a group of 41 diverse inbred sorghum lines. Callus cultures of 20 elite inbred sorghum genotypes and 21 inbred genotypes of exotic background were initiated from immature inflorescences. The cultures were subjected to several cycles of subculturing …

Expression Of Follistatin And Inhibin/Activin Subunit Genes In Porcine Follicles, M.D. Li, L.V. Depaolo, J.J. Ford

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

Expression of the follistatin (FS) and inhibin/activin (I/A) α, β_A, and β_B subunit genes in porcine ovarian follicles was evaluated by reverse transcriptase polymerase chain reaction and/or RNase protection procedures to establish changes during the final stages of follicular development. For the I/A α and β_A subunits, expression increased (p < 0.05) as follicles progressed to the mid-stage of the follicular phase. The β_B, subunit was expressed in lower concentrations, and all three I/A subunits showed a marked reduction (p < 0.01) in expression by the late stage of follicular development. In contrast to this pattern, FS gene expression decreased (p < 0.05) as follicles developed from the early (low estradiol) to the mid stage (high estradiol) and continued to decline in advanced follicles (after estrus). The predominant mRNA encoded for FS-315, and the ratio of mRNA for FS-315 to mRNA for FS-288 did not differ significantly during the three stages. Within an animal, concentration of FS mRNAs was related more to stage of the follicular phase than to follicular size. Follicular fluid concentration of FS changed in a manner similar to that observed for expression of its gene. We conclude that expression of the FS gene and translation of its mRNA decrease as follicles approach ovulatory status.

Yield Of Wheat Across A Subambient Carbon Dioxide Gradient, Herman S. Mayeux, Hyrum B. Johnson, H. Wayne Polley, Stephen R. Malone

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

Yields and yield components of two cultivars of day-neutral spring wheat (Triticum aestivum L.) were assessed along a gradient of daytime carbon dioxide (CO₂) concentrations from about 200 to near 350 µmol CO₂ (mol air)^–1 in a 38 m-long controlled environment chamber. The range in CO₂ concentration studied approximates that of Earth’s atmosphere since the last ice age. This 75% rise in CO₂ concentration increased grain yields more than 200% under well-watered conditions and by 80–150% when wheat was grown without additions of water during the last half of the 100-day growing season. …

Genetic Variation In North American Leafy Spurge (Euphorbia Esula) Determined By Dna Markers, Martha L. Rowe, Donald J. Lee, Scott Nissen, Brunella M. Bowditch, Robert A. Masters

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

Levels of inter- and intrapopulation genetic variation were determined in five North American populations of leafy spurge using chloroplast DNA (cpDNA) RFLPs and RAPD markers. Thirteen plastome types were identified among 123 individuals collected from five geographically separated populations. Number of pastimes within a population ranged from one to seven, with four of the populations having a predominate type plus one or more rarer types. Some plastome types were shared by populations, but plastome distribution among populations was nonrandom. RAPD markers indicated greatest relatedness among individuals within a population. Relatedness among populations as established through RAPDs was greater for geographically …

Transmittance And Reflectance Measurements Of Corn Leaves From Plants With Different Nitrogen And Water Supply, James S. Schepers, T. M. Blackmer, Wallace Wilhelm, M. Resende

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

Nitrogen is essential for crop production, but also contributes to eutrophication of surface water and degradation of drinking water quality. Modern corn production requires relatively large quantities of N, which are generally supplied by fertilizers. Over-application of N fertilizers and animal wastes frequently results in nitrate leaching. Synchronizing N availability with crop N need offers the potential to protect the environment without sacrificing production. Tools are needed to rapidly and easily monitor crop N status to make timely decisions regarding fertilizer application. Analytical and optical techniques were evaluated with greenhouse grown corn at silking to evaluate several methods to monitor …

Proceedings Of The International Conference On Genetic Improvement Of Sorghum And Pearl Millet, Darrell Rosenow, Gary Peterson, John Mullet, Henry Nguyen, Gebisa Ejeta, John Axtell, David Andrews, Jeff Dahlberg, A. Bruce Maunder, Kay Porter, Mike Gilbert, John Witcombe, John Stenhouse, C. Tom Hash, Kanayo Nwanze, Sam Mukuru, Anand Kumar, Francisco Gomez, Aboubacar Toure, Ouendeba Botorou

INTSORMIL Impacts and Bulletins

In 1971, an international symposium, "Sorghum in the Seventies", organized by the All India Coordinated Sorghum Improvement Project with support from the Indian Council of Agricultural Research and the Rockefeller Foundation was held in Hyderabad, India. The symposium reviewed the current knowledge base of the scientific, production and nutritional aspects of sorghum as a crop and as a human food. In 1981, ICRISAT, INTSORMIL, and the Indian Council of Agricultural Research (ICAR) sponsored "Sorghum in the Eighties", an international symposium at ICRISAT Center in India, to review the achievements accomplished in sorghum research during the preceding 10 years. They reviewed …

Monoclonal Antibodies For Detection Of The H7 Antigen Of Escherichia Coli, Yongsheng He, James E. Keen, Ralph B. Westerman, E. Travis Littledike, Jimmy Kwang

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

Two murine monoclonal antibodies (MAbs) (2B7 and 46E9-9) reactive with the H7 flagellar antigen of Escherichia coli were produced and characterized. A total of 217 E. coli strains (48 O157:H7, 4 O157:NM, 23 O157:non-H7, 22 H7:non-O157, and 120 non-O157:non-H7), 17 Salmonella serovars, and 29 other gramnegative bacteria were used to evaluate the reactivities of the two MAbs by indirect enzyme-linked immunosorbent assay (ELISA). Both MAbs reacted strongly with all E. coli strains possessing the H7 antigen and with H23- and H24-positive E. coli strains. Indirect ELISA MAb specificity was confirmed by inhibition ELISA and by Western blotting (immunoblotting), using partially …

Outdoor Living Barn: A Specialized Windbreak, Kris Irwin, Jerry Bratton

Agroforestry Notes (USDA-NAC)

In April of 1987, a spring blizzard swept through northern Kansas and southern Nebraska killing nearly 60,000 newborn calves and other winter stressed animals. This tremendous loss could have been lessened had protection, such as outdoor living barns (OLB), been provided to reduce the windchill. An outdoor living barn is a specialized windbreak, typically composed of trees and shrubs, and strategically located in open grasslands, center pivot irrigation corners, and pasture areas to protect livestock during severe weather situations.

The purpose of an OLB is to: 1) defuse and deflect cold winds away from livestock, moderating the windchill; and 2) …

Spikelet And Floret Naming Scheme For Grasses With A Spike Inflorescence, Wallace Wilhelm, Gregory S. Mcmaster

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

Effective schemes to name uniquely and define parts of grass plants allow researchers to communicate results of their experiments accurately and precisely. Naming schemes for vegetative parts of grass plants have been developed; however, no system exists to name uniquely parts of the inflorescence. In this report, we present a method to extend existing systems to name parts of grass spikes. Spikelet positions are denoted by the letter S and numbered acropetally along the rachis. For example, the third spikelet position from the base of the rachis is named S3. Likewise, floret positions along the rachilla are named F (or …

The Structural Gene Encoding Human Enterotoxigenic Escherichia Coli Pcfo20 Is Homologous To That For Porcine 987p, Gloria Inés Viboud, Gunhild Jonson, Evelyn A. Dean-Nystrom, Ann-Mari Svennerholm

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

Putative colonization factor PCFO20 was recently identified in an enterotoxigenic Escherichia coli (ETEC) strain of serogroup O20 isolated from a child with diarrhea in Argentina. The gene encoding the structural subunit of PCFO20 fimbriae, fotA, was cloned from strain ARG-2 in the expression phage vector lambda ZAP Express. One positive clone, pGV29, that carried a 3.3-kb fragment was identified on the basis of fimbrillin production by using a monospecific rabbit anti-PCFO20 serum. Nucleotide sequencing of a 1.3-kb Sau3A-ClaI fragment of the subclone pGV292 containing the region coding for PCFO20 fimbrillin revealed two open reading frames of …

Proceedings Of The 23rd Annual Meeting, Southern Soybean Disease Workers (March 24-25, 1996, Biloxi, Mississippi), Brian M. Anderson, Robert P. Mulrooney, Gabe Sciumbato, John Russin, Glenn G. Hammes

Southern Soybean Disease Workers: Conference Proceedings

Contents

Business session

Soybean Disease Loss Estimate for the Southern United States during 1995. JA Wrather

Treasurer report. GG Hammes

SSDW Committee Chairmen for 1995-1996

Graduate student papers

Effects of Bacteria Associated with Heterodera glycines in Soybean Fields of Arkansas. TK Field, RD Riggs, and TL Hart

Influence of Soybean Pest Complexes on Maturation of Soybean Looper, Pseudoplusia includens. CH Carter, JS Russin, EC McGawley, DJ Boethel, and JL Griffin

Contributed papers

Resistance to Cyst Nematode in PI 437654 and Hartwig Soybeans. SC Ananad

Rotation with Soybean Cultivar Hartwig and Nonhost Crops for Management of the Soybean Cyst Nematode. …

Planting Date And Residue Rate Effects On Growth, Partitioning, And Yield Of Corn, Stephan Swanson, Wallace Wilhelm

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

Corn (Zea mays L.) growth has been shown to be affected by planting date and amount of residue on the soil surface. The objective of this study was to determine if the adverse effects of cool soil temperatures on early seedling growth often associated with surface residues can be overcome by planting at later dates. Corn was planted at several planting dates (late April through early June) into soil that had residue applied at rates of 0, 33, 66, and 100% of that produced by the previous crop. In general, spring-applied residue rates had little effect on measured plant …

Tallgrass Prairie Vegetation Response To Spring Burning Dates, Fertilizer, And Atrazine, Robert B. Mitchell, Robert A. Masters, Steven S. Waller, Kenneth Moore, Linda J. Young

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

Tallgrass prairies provide an important source of hay and summer forage in eastern Nebraska. A study was conducted in 1989 and 1990 on 2 late seral tallgrass prairies near Lincoln and Virginia, Nebraska to determine if production of selected components of tallgrass prairie communities could be altered by burning (not burned, or burned in either early, mid-, or late spring) and applying fertilizer (0 and 67-23 kg N-P ha^-1) and atrazine [6- chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine] (0 and 2.2 kg a.i. ha^-1). Vegetation was harvested the year treatments were applied at about 30-day intervals starting in June and ending …

Harvest Frequency And Burning Effects On Monocultures Of 3 Warm-Season Grasses, Gregory J. Cuomo, Bruce Anderson, Linda J. Young, Wally Wilhelm

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

Harvest frequency and burning can affect forage yield of monocultures of switchgrass (Panicurn virgutum L.), big bluestem (Andropogon gerurdii Vitman), and Indian grass [Sorghastrum nutuns (L.) Nash]. Current information is based largely on results from mixed stands. A field experiment was established in 1986, and from 1988 to 1991 treatments were applied with burning in March, April, or May plus an unburned control. Growing season yield was measured by harvesting 1 (June), 2 (June and July), or 3 (June, July, and August) times with unharvested control plots included. End-of-season standing crop from all plots was determined …

Germplasm And Cultivar Development, M. D. Casler, Jeffrey F. Pedersen, G. C. Eizenga, S. D. Stratton

Department of Agronomy and Horticulture: Faculty Publications

Cool-season forage grasses have evolved, and continue to evolve, in natural ecosystems subject to environmental factors both in the presence and absence of human influences. The literature often lacks facts describing the evolution and domestication of forage grasses. Furthermore, the literature on this subject mainly deals with evolution of species in the broad scope, i.e., on a scale of hundreds of thousands or millions or years. Thus, some of our conclusions are necessarily speculative and are highly subject to the nature of the research that has been reported. We describe the forces of selection that act upon cool-season forage grasses …

Nf96-273 Establishment Of Kentucky Bluegrass For Seed Production In The Nebraska Panhandle And Southeastern Wyoming, Ray E. Weed, David D. Baltensperger, Robert C. Shearman, Roger Hammons, Jim Krall

University of Nebraska-Lincoln Extension: Historical Materials

This NebFact contains information on selecting turfgrass seed fields, preparation of the fields for seeding, fertilizing for grass establishment, seeding, certification of seed quality, cultivar selection and quality maintenance, and suggested additional readings and resources.

Application Of The Single Kernel Wheat Characterization Technology To Sorghum Grain, Jeffrey F. Pedersen, C. R. Martin, F. C. Felker, J. L. Steele

Department of Agronomy and Horticulture: Faculty Publications

A single kernel wheat characterization system (SKWCS) was recently developed by the USDA, ARS Grain Marketing Research Laboratory and is currently being marketed by Perten Instruments North America, Inc. This device has been shown to accurately measure individual seed hardness, moisture, and size of wheat. The objective of this study was to determine if the SKWCS technology could be applied to the measurement of sorghum grain. Grains from 64 sorghum plots grown at Mead, NE in 1992 were characterized using a prototype SKWCS at the USDA, ARS Grain Marketing Research Laboratory. Problems encountered were primarily associated with the single kernel …

Development Of House Flies (Diptera: Muscidae) In Sand Containing Varying Amounts Of Manure Solids And Moisture, Jerome Hogsette

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

House flies, Musca domestica L., developed in 200 cm³ of coarse sand containing just 1 ml (0.47%) of dairy manure solids and 10 ml (4.74%) of moisture. At these levels, development was slow (21.5 d from 1st instar to adult), adult survival was low (7.5%), but successful development did occur. At higher manure and moisture levels, rates of development and survival were similar to those reported previously. All soil samples collected from a feedlot dairy contained higher levels of manure solids than the highest level tested in the laboratory. The implications for fly control in soil/manure mixtures and the …

Permethrin-Impregnated Yarn: Longevity Of Efficacy And Potential Use On Cylindrical Fiberglass Stable Fly (Diptera: Muscidae) Traps, Jerome Hogsette, Joseph Ruff

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

Efficacy of permethrin-impregnated orlon yam against stable flies, Stomoxys calcitrans (L.), was 6-8 wk under simulated field conditions. Numbers of stable flies captured on corrugated cylindrical fiberglass traps painted with an adhesive indicated that these traps are attractive enough to be used in the field with treated yam applied. Reasons for variability of yam impregnation and the use of yam on cylinder traps are discussed.

Imidazolinone Herbicides Improve Restoration Of Great Plains Grasslands, Robert A. Masters, Scott Nissen, Roch E. Gaussoin, Daniel Beran, Robert Stougaard

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

The productivity and native species diversity of Great Plains grasslands have been substantially reduced by past management that facilitated the establishment of invasive exotic weeds and displacement of native species. Management strategies are needed to rapidly restore the productive capacity and biological diversity of these degraded grasslands. Critically important phases of the grassland restoration process are the reintroduction and establishment of native species. Weed interference is the primary constraint to successful establishment of native plants. The goal of our research is to develop strategies that use multiple technologies, including herbicides, to expedite grassland revegetation with native grasses and forbs. Imidazolinon …

Annual Forages: New Approaches For C-4 Forages, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

The current agricultural paradigm in the U.S. is heavily biased towards the production and marketing of crops as commodities. This paradigm is kept in place by grain handling and marketing infrastructure, as well as government farm programs, designed for crops as commodities. Sorghum (Sorghum bicolor L. Moench) and maize (Zea mays L.) grown for grain certainly fit into this current paradigm.

A new approach to agricultural production and marketing, identity preserved products, is gaining in importance. This is made possible through new technologies and markets demanding products designed specifically for their needs. Examples of investment in identity preserved …

Breeding Sorghum And Pearl Millet For Forage And Fuel, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Sorghum [Sorghum bicolor (L.) Moench] and pearl millet [Pennisetum glaucum (L.) R. Br.] are unique species in their ability to be used in many forage llivestock system roles. Such flexibility has made prioritizing breeding objectives difficult and has even contributed to contradictory opinions on appropriate forage breeding objectives. Few breeding projects identified in the USDA-ARS, USDA-CREES, or at ICRISAT had forage sorghum or forage pearl millet as their sole research assignment. In the United States, it can be argued that breeding resources committed to forage sorghum improvement are probably declining. A new forage sorghum and forage pearl millet …

Media Effects On Phenotype Of Callus Cultures Initiated From Photoperiod-Insensitive, Elite Inbred Sorghum Lines, H. F. Kaeppler, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Sorghum (Sorghum bicolor L. Moench) is a crop of worldwide agronomic importance. Routine production of high quality (friable, embryogenic, fast growing) callus cultures is fundamental to tissue culture based genetic study and improvement of sorghum. Genotype by culture medium interactions for sorghum callus growth and morphology have been previously reported. The objective of this study was to identify tissue culture media that would support high quality callus growth across photoperiod insensitive, relatively elite genotypes. Explants from immature inflorescences of 11 sorghum genotypes were cultured on 6 tissue culture media of differing composition. After 3 and 5 months in culture, calli …

Semiochemistry Of Cabbage Bugs (Heteroptera: Pentatomidae: Eurydema And Murgada, Jeffrey R. Aldrich, James W. Avery, Chang-Joo Lee, Jennifer C. Graf, Dawn J. Harrison, Ferdinando Bin

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

The semiochemistry of the common North American pest of crucifers, Murgantia histrionica (Hahn) (the harlequin bug), and two related European species, Eurydema ventrale L. and E. oleraceum L., was investigated.

Carbonate And Gypsum, Richard H. Loeppert, Donald L. Suarez

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

The carbonate minerals and gypsum exert a dominating influence on soils in
which they are present because of their relatively high solubility, and in the case
of the carbonates, their alkalinity and pH buffering properties. In this chapter,
procedures for the determination of quantity, reactivity and equilibrium relations
of these minerals will be discussed.

Leafy Spurge (Euphorbia Esula) Genotype Affects Gall Midge (Spurgia Esulae) Establishment, Rodney G. Lym, Scott Nissen, Martha Rowe, Donald J. Lee, Robert A. Masters

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

Greenhouse cage studies were conducted to determine the influence of shoot morphology and genetic variation on establishment of Spurgia sulae gall midge on seven leafy spurge genotypes. The genotypes were collected from South Dakota, North Dakota, Nebraska, Montana, Wyoming, Manitoba, and Austria. Genotypes from South Dakota and Nebraska were most susceptible to gall formation and had the highest larvae survival, while the genotypes from Montana and Manitoba were most resistant. Morphological characteristics of the leafy spurge stem tips, such as stem diameter leaf, length, width, and area did not correlate with gall formation or larvae survival. Chloroplast DNA restriction fragment …

Accuracy Of Equations Predicting The Phyllochron Of Wheat, Gregory S. Mcmaster, Wallace Wilhelm

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

Predicting the rate of leaf appearance, or phyllochron, aids in understanding and modeling grass development and growth. Nine equations predicting the phyllochron of wheat (Triticum aestivum L.) were evaluated using field data from a variety of locations, cultivars, and management practices. Each equation is referred to by the last name of the first author; if there is more than one equation by the first author, additional descriptors were included. The BAKER and KIRBY equations predict the phyllochron based on changes in daylength following seedling emergence; CAO-TEMP and CAO-DAY use a curvilinear relationship with temperature and daylength, respectively; CAO-T&D uses the …

Corn-Soybean Rotation Effects On Soil And Plant N Indices, G. E. Varvel, N. L. Klocke, Wallace Wilhelm

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

An irrigated study comparing monoculture corn and corn-soybean systems is being conducted on a uniform site in the Platte Valley of Nebraska. Four corn hybrids differing in yield potential, maturity, and stay-green characteristics are used in both the monoculture and rotation systems with five N-fertilizer rates. Stalk nitrate-nitrogen concentrations determined in mature corn plants at harvest have been used in many areas of the country as an indicator of the amount of N available to those plants. In this study, stalk nitrate-nitrogen concentrations (taken after the 1992 and 1993 growing seasons) reflected differences in N status between and within the …

Addition Of Cellulolytic Clostridia To The Bovine Rumen And Pig Intestinal Tract, Vincent H. Varel, J.T. Yen, Kelly K. Kreikmeier

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

Studies were conducted to determine whether intestinal cellulolytic bacteria could be introduced into the bovine rumen or pig large intestine. In the first study, the ruminal fluid of three cows was evacuated and replaced with 20 liters of buffer and 6 liters of the ruminal or swine cellulolytic organism Clostridium longisporum or Clostridium herbivorans, respectively. The introduced organisms were the predominant cellulolytic bacterium in the fluid (>107 cells ml21) at 0 h. C. longisporum was still the predominant cellulolytic organism after 5 h, at 0.55 3 107 cells ml21; however, after 24 h the count of C. longisporum …

Yield And N Uptake Of Inbred Corn With Reduced N-Fertilizer Application, Wallace Wilhelm, B. E. Johnson, R. Koopman, W. R. Peterson

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

Most corn planted in the United States is a single-cross hybrid; therefore the seed is produced on inbred lines. Inbreds are known to be less productive than the resultant hybrids; however, growers and seed companies want to maximize seed production. To this end growers attempt to keep mineral nutrition, especially nitrogen, non-limiting. Low production potential and high N fertilization rates can result in the likelihood of groundwater contamination. Key to proper N application is knowledge of the N response of inbred lines. The purpose of this research was to determine the yield and N uptake response of a group of …