Agricultural Science Commons^™

Scales 2: Computer Program To Convert Among Developmental Stage Scales For Corn And Small Grains, Dorothy M. Harrell, Wallace Wilhelm, Gregory S. Mcmaster

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

Producers and agronomists need crop developmental scales that are easy to use, universally accepted, and accurate. Development of such a scale requires correlation of stages among scales currently in use and correlation of developmental patterns among crops. A computer program for converting among staging systems is a useful tool in developing new staging systems with wider applicability. The BBCH scale (BASF-Bayer-Ciba-Geigy-Hoechst) has been proposed as a prototype of a universal scale. We have added the BBCH scale to our scale conversion program for wheat (Triticum aestivum L.) and developed a similar conversion program for corn (Zea mays L.), …

Comparisons Of Soil Physical Characteristics In Long-Term Tillage Winter Wheat-Fallow Tillage Experiments, L. N. Mielke, Wallace Wilhelm

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

Soil physical characteristics resulting from tillage of fallow-wheat (Triticurn aestivurn L.) cropping systems were compared for two soils in western Nebraska. The soil physical environment influences the amount of water entering soil and the microenvironment that influences soil biological processes important to plant response. Effects of tillage on physical properties varied with soil type and depth of soil tillage. Generally, the 0-76 mm surface layer has the largest number of physical properties that differ as a result of tillage; however, only a few properties differed at greater depths. The Alliance silt loam (fine silty, mixed, mesic, Aridic Arguistoll) soil …

Comparison Of Water And Temperature Distribution Profiles Under Sand Tube Irrigation, Masoud Meshkat, Richard C. Warner, Stephen R. Workman

Biosystems and Agricultural Engineering Faculty Publications

Drip irrigation is one of the most efficient systems in delivering water to the plant root zone. Research has shown that the saturated, or nearly saturated, surface beneath the emitter may increase evaporation thereby reducing the irrigation efficiency. To increase the efficiency of surface applied drip irrigation on permanent tree crops a sand tube irrigation (STI) method was developed and tested. The sand tube method consists of removing a soil core beneath the emitter and filling the void with coarse sand. A weighing lysimeter was designed and instrumented to directly measure temporal evaporation during irrigation and for a period of …

Dry-Matter Partitioning And Leaf Area Of Winter Wheat Grown In A Long-Term Fallow Tillage Comparisons In The Us Central Great Plains, Wallace Wilhelm

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

Crop management practices (tillage, residue management, fertilization, etc.) define the soil environment to which crops are exposed and through these environmental conditions control crop growth. The purpose of this paper is to report the response of winter wheat (Triticum aestivum L.) to long-term (10 years) application of fallow tillage practices (plow, sub-till, and no-till) and N fertilization in terms of above- and below-ground dry-matter partitioning. During 1978, less winter wheat root tissue was produced in the sub-till treatment compared to the average of the plow and no-till treatments. However, in 1979, all treatments produced the same amount of root …

Potential Of The Entomopathogenic Fungus, Metarhizium Anisopliae (Metsch.) Sorokin For Control Of The Legume Flower Thrips, Megalurothrips Sjostedti (Trybom) On Cowpea In Kenya, S. Ekesi, N. K. Maniania, K. Ampong-Nyarko, I. Onu

All Peer-Reviewed Publications

Field experiments were conducted at Mbita, western Kenya for two seasons to evaluate the potential of the entomopathogenic fungus, Metarhizium anisopliae (Metsh.) Sorokin, for biological control of the legume flower thrips, Megalurothrips sjostedti (Trybom), on cowpea. An ultra-low-volume (ULV) oil/aqueous formulation and a high-volume (HV) aqueous formulation of conidia were applied three times each at two concentrations of 1 x 1011 and 1 x 1013 conidia ha-1. Compared with the untreated controls, both formulations significantly reduced thrips populations and plant damage in both seasons. Adult insects collected from fungal-treated plots and reared in the laboratory showed a high mortality due …

Escherichia Coli O157:H7 Requires Intimin For Enteropathogenicity In Calves, Evelyn A. Dean-Nystrom, Brad T. Bosworth, Harley W. Moon, Alison D. O’Brien

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

Enterohemorrhagic Escherichia coli (EHEC) strains require intimin to induce attaching and effacing (A/E) lesions in newborn piglets. Infection of newborn calves with intimin-positive or intimin-negative EHEC O157: H7 demonstrated that intimin is needed for colonization, A/E lesions, and disease in cattle. These results suggest that experiments to determine if intimin-based vaccines reduce O157:H7 levels in cattle are warranted.

Is Soil Temperature Better Than Air Temperature For Predicting Winter Wheat Phenology?, Gregory S. Mcmaster, Wallace Wilhelm

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

In predicting wheat (Triticum aestivum L.) phenology, logic suggests that basing thermal unit accumulation on near-surface soil temperature should give a better representation of shoot apex thermal unit accumulation than air temperature until internode elongation raises the apex above the soil surface. A study was undertaken to determine if predictions of winter wheat phenology are improved when based on measured near-surface soil temperature rather than air temperature. Air temperature 1.5 m above the soil surface and soil temperature at crown depth (the position of the shoot apex before stem elongation) were collected for 23 site-years across the U.S. Central …

Biodegradation Of Atrazine By Agrobacterium Radiobacter J14a And Use Of This Strain In Bioremediation Of Contaminated Soil, J. K. Struthers, K. Jayachandran, T. B. Moorman

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

We examined the ability of a soil bacterium, Agrobacterium radiobacter J14a, to degrade the herbicide atrazine under a variety of cultural conditions, and we used this bacterium to increase the biodegradation of atrazine in soils from agricultural chemical distribution sites. J14a cells grown in nitrogen-free medium with citrate and sucrose as carbon sources mineralized 94% of 50 μg of [¹⁴C-U-ring]atrazine ml^-1 in 72 h with a concurrent increase in the population size from 7.9 x 10⁵ to 5.0 x 10⁷ cells ml^-1. Under these conditions cells mineralized the [ethyl-¹⁴C]atrazine …

The Chickpea Book : A Technical Guide To Chickpea Production, Stephen Loss, Neil Brandon, K H M. Siddique

Bulletins 4000 -

The area of chickpea production in Australia has expanded rapidly in recent years especially in south-western Australia. This has been partly brought about by the keen interest of farmers and a concerted research effort and industry development by Agriculture Western Australia, The Centre for Legumes in Mediterranean Agriculture (CLIMA) and other institutions, in partnership with the Grains Research and Development Corporation and other industry funding bodies. Private consultants, grain traders and other industry groups have also contributed to the expansion of the industry.

Much of the local knowledge generated by these research and development projects has been published in various …

Residual Effects Of Crop Residues On Grain Production And Selected Soil Properties, James F. Power, Paul Koerner, John W. Doran, Wallace Wilhelm

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

Returning crop residue improves water conservation and storage, nutrient availability, and crop yields. We have little knowledge, however, of the residual impacts of crop residues on soil and crop production. We hypothesized that residual impacts of crop residues vary with the amount of residues used. A 10-yr study near Lincoln, NE, evaluated the residual effects of an earlier 8-yr study of various crop residue amounts on crop growth and selected soil properties. From 1978 through 1985, crop residues were returned at 0,50, 100, and 150% of the quantity produced by the previous crop (averaging 0 to =6 Mg ha^{-1 …}

Legume Logic Number 95

Legume Logic

Contents

Seasonal situation

Safe cropping

Pulse points

Herbicide damage

AgraCorp Pulse Indicator Prices as 23 June

Controlling grass weeds in pulse crops

Post-emergent broadleafed weed control

Legume Logic Number 94

Legume Logic

Contents

Sustainability

Lupin price outlook

Seasonal conditions

Opportunities For Growing Short-Rotation Woody Crops In Agroforestry Practices, Gary A. Kuhn, W. J. Rietveld

Agroforestry Notes (USDA-NAC)

Technologies are readily available for growing hybrid poplars and willows in block plantings as short-rotation woody crops (SRWC) for fuel and fiber. SRWC species and technologies can also be incorporated into agricultural systems as agroforestry practices. Examples are windbreaks, living snowfences, “timberbelts”, riparian buffer strips, and wastewater treatment plantings. Fast growth, convenient propagation (see AF Note - 11), and compatibility with conventional farming methods make SRWC suitable for use in agroforestry practices to provide multiple benefits such as solid wood and wood fiber products, water quality improvement, crop and soil protection, wildlife habitat, and buffers for agricultural/community interfaces.

Establishment And Cultural Guidelines For Using Hybrid Tree Species In Agroforestry Plantings, Gary A. Kuhn, W. J. Rietveld, Don E. Riemenschneider

Agroforestry Notes (USDA-NAC)

Hybrid poplars (and willows) are well-suited for agroforestry applications in many parts of the United States (See AFN-10). Their convenient propagation and fast growth allow them to establish and provide conservation benefits more quickly. This note provides general establishment and cultural guidelines to consider when using hybrid poplar cuttings for agroforestry plantings.

Differentiation Of F18ab+ From F18ac+ Escherichia Coli By Single-Strand Conformational Polymorphism Analysis Of The Major Fimbrial Subunit Gene (Feda), Brad T. Bosworth, Evelyn A. Dean-Nystrom, Thomas A. Casey, Holly L. Neibergs

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

Toxin-producing Escherichia coli expressing F18 fimbriae colonizes the small intestines of weaned pigs and causes diarrhea, edema disease, or both. The F18 family is composed of two antigenic variants, F18ab and F18ac. Because many strains do not express F18 fimbriae in vitro, identification and differentiation of these two variants are difficult. Single-strand conformational polymorphism (SSCP) analysis is a rapid method for identifying genetic mutations and polymorphisms. The F18 major fimbrial subunit genes (fedA) of 138 strains were amplified by PCR, and genetic differences were detected by SSCP analysis. The SSCP analysis of the fedA gene differentiated F18ab^{+ …}

Export Carrot Production Capability Study, Dennis Phillips

Horticulture research reports

A survey was conducted by personal interview of nearly 80 per cent of Western Australian export carrot growers to determine the range of business profiles and production practices prevailing in the industry in 1996-97. The study provided significant information which the industry can use to guide future development and to benchmark its performance.

The industry was characterised by a high level of Australian ownership and a healthy mix of family and corporate ownership and vertical integration. Capital investment in production was high, potentially inhibiting new entrants to the industry.

Threats to future industry growth were identified in an ageing management …

Guidelines Of Activities And Costs Of Establishing A Vineyard For Winegrapes, Alex Sas, Roslyn Hanna, Diana Fisher

Viticulture published reports

This document is intended as a starting point for those interested in growing wine grapes and highlights the management techniques, labour requirements, and costs involved with such an enterprise. Budgeting methods are used to determine the profitability of investing in a 10 ha vineyard in the south-west of Western Australia. The document should not be used as a recipe with which to develop a vineyard, but rather as a guide.

Establishing a vineyard involves a large initial investment with no returns until usually three years after planting. Factors such as site selection, environment, seasonal conditions and management, will all affect …

Development Of A Blocking Enzyme-Linked Immunosorbent Assay For Detection Of Serum Antibodies To O157 Antigen Of Escherichia Coli, William Laegreid, Mark Hoffman, James Keen, Robert Elder, Jimmy Kwang

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

The O157 antigen of Escherichia coli shares structural elements with lipopolysaccharide (LPS) antigens of other bacterial species, notably Brucella abortus and Yersinia enterocolitica O9, a fact that confounds the interpretation of assays for anti-O157 antibodies. To address this problem, a blocking enzyme-linked immunosorbent assay (bELISA) was designed with E. coli O157:H7 LPS as the antigen and a monoclonal antibody specific for E. coli O157, designated 13B3, as the competing antibody. The bELISA had equivalent sensitivity to, and significantly higher specificity than, the indirect ELISA (iELISA), detecting anti-O157 antibodies in sera from cattle experimentally inoculated with O157:H7. Only 13% of sera …

An Inventory And Condition Survey Of The Sandstone-Yalgoo-Paynes Find Area, Western Australia, A L. Payne, A M E Van Vreeswyk, K A. Leighton, H J. Pringle, P Hennig

Technical Bulletins

The inventory and condition survey of the Sandstone-Yalgoo-Paynes Find area, undertaken by the Department of Agriculture and Food, Western Australia (DAFWA) between 1992 and 1993, describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the area’s natural resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The area surveyed covers about …

Linking People, Purpose, And Place: An Ecological Approach To Agriculture, Heidi Carter, Richard Olson, Charles A. Francis

CARI Extension and Education Materials for Sustainable Agriculture

Linking Ecology and Agriculture

Whole Farm Planning

Soil Quality

Agroforestry

Grazing Systems

Weed and Insect Management

Farmer Groups

Farmland Conversion

Resources and Information Sources

Gas Chromatography/Mass Spectrometry Analysis Of The Cuticular Hydrocarbons From Parasitic Wasps Of The Genus Muscidifurax, Ulrich R. Bernier, David A. Carlson, Christopher J. Geden

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

Parasitic Hymenoptera can be difficult to identify by conventional taxonomic techniques. Examination of the cuticular hydrocarbons (CHCs) provides a basis for chemotaxonomic differentiation, which may lead to the discovery of pheromones, and can be a means of examining colonies for species cross-contamination. The parasitic wasps examined were Muscidifurax raptor, M. zaraptor, M. uniraptor, and the gregarious form of M. raptorellus. Species within the genus Muscidifurax, as well as the sex, can clearly be differentiated by examining the gas chromatograms of the CHCs. Identification of the alkanes by mass spectrometry shows uncommon dimethylalkanes and trimethylalkanes for members of the …

Elution Patterns From Capillary Gc For Methyl-Branched Alkanes, David A. Carlson, Ulrich R. Bernier, Bruce D. Sutton

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

A common and confusing problem in analyses of insect hydrocarbons is in making sense of complicated gas chromatograms and interpreting mass spectra since branched chain compounds differing by one or two carbons in backbone or chain length may elute from the column at nearly the same time. To address this confusing situation, relative gas chromatography (GC) retention times are presented for typical mono-, di-, tri-, and tetramethylalkanes comprising most of the commonly appearing series of homologous methyl-branched alkanes up to 53 carbons that are found in insect cuticular hydrocarbons. Typical insect-derived methylalkanes with backbones of 33 carbons were characterized by …

Black Flies, Simulium Spp. (Insecta: Diptera: Simuliidae), J. F. Butler, J. A. Hogsette

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

Introduction

Florida occasionally experiences outbreaks of black flies, though this is a rare occurance, and these large populations are caused by rainfall extremes. Common names for this pest include black flies and turkey gnats, as well as a number of new names applied by Floridians which are not repeatable here. Because of the hump visible behind their head when viewed in profile, black flies are also called buffalo gnats. Like eye gnats, they fly around people's heads, occasionally getting into eyes and ears as well as crawling in the hair. Because most of the specimens collected to date have been …

Spatial Pattern Of Gas Exchange For Montane Moist Meadow Species, Tony Svejcar, Gregg M. Riegel

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

Montane moist meadows of western North America are relatively unique in that they are characterized by annual cycles of spring inundation followed by summer drought. Thus, plants adapted to these ecosystems must cope with a wide range of environmental conditions. We compared gas exchange and water relations of upper canopy leaves and leaf area index (LAI) of three dominant montane meadow graminoids growing at both streamside and mid-meadow locations (2.5 and 20.0 m, respectively from the stream edge). The two locations were environmentally very different in spite of their close proximity. The water table at the streamside location was ca. …

Yield And Stability Factors Associated With Hybrid Wheat, R. Bruns, C. J. Peterson

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

For hybrid wheat to be accepted in the Great Plains of the USA, hybrids must exhibit enhanced yield performance, yield responsiveness, and reasonable yield stability across a wide array of production environments. Agripro has been researching hybrid wheat since 1981 and has an established pureline release history since 1978. Yield data from 1991 to 1995 were examined to compare the trend performance and selection gains of purelines and hybrids in a large scale parallel development effort. This data set (13,739 points) reveals an average 0.454 t ha^–1 or 10.8% hybrid yield advantage over purelines in preliminary regional testing. Entries …

Physiology And Reproduction: Gross Appearance Of The Turkey Blastoderm At Oviposition, M. R. Bakst, S. K. Gupta, W. Potts, V. Akuffo

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

The blastoderm (fertilized ovum) and unfertilized germinal disc (UGD) of fresh laid eggs and eggs stored prior to incubation exhibit subtle but definable morphological variations. Such variations may lead to difficulty when attempting to determine true flock fertility based on the appearance of the blastoderm/UGD. The objectives of this study were to define and categorize such morphological variations and to determine whether sperm influence the frequency distribution of the different categories. Eleven categories of blastoderms were defined based on the relative density and appearance of the area alba, area pellucida, area opaca, and the periblast. The majority of the blastoderms …

Northern Australia Quarantine Strategy. Weeds Target List, B. M. Waterhouse, A A. Mitchell

Biosecurity published reports

Second edition.

The Northern Australia Quarantine Strategy (NAQS) was established in 1989 as an outcome of a major evaluation of quarantine in Australia (AGPS 1987, 1988). NAQS activities include surveying for weeds,insect pests and diseases of plants; and pests and diseases of animals in northern Australia, Papua New Guinea and Indonesia. The primary goal is to provide early detection and warning of new quarantine threats or incursions.

A targetted approach was adopted for all pests, diseases and weeds. For each category of pest, experts in the discipline compiled lists of organisms not known from Australia but known to occur in …

Inactivation Of Soybean Peroxidase During Sodium Azide Oxidation: A Comparative Study, Mohamed Yehia Zakaria Aboul Eish

Dissertations and Theses @ UNI

Azide ion is a mechanism-based inactivator of a number of peroxidases. However, there are often variations in the manner in which inactivation occurs. Soybean Peroxidase (SBP) is found in the plant's seed coat. Unlike many other peroxidases, a single enzyme rather than several isozymes are produced thus making more simple the purification and characterization of the enzyme. In this research it was shown that, as with other peroxidases, SBP is inactivated by azide during turnover. During azide oxidation SBP forms a ferrous-NO intermediate. In this respect, SBP is similar to the lignin peroxidases from Phanerochaete chrysosporium which also form ferrous-NO …

Structure Of The Avian Oviduct With Emphasis On Sperm Storage In Poultry, Murray R. Bakst

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

The macroanatomy, histology, and fine structure of the avian oviduct is reviewed and related to its role in fertile egg production. The avian oviduct functions as a biological assembly line, beginning sequentially with the deposition of the albumen around the fertilized or unfertilized ovum, then the shell membrane, and lastly, the shell, all within 25 hr of ovulation. While in transit through the oviduct, the fertilized ovum progresses to the pre-gastrulation stage of development.

Comparative Gene Mapping: Cytogenetic Localization Of Proc, En1, Alpi, Tnp1, And Il1b In Cattle And Sheep Reveals A Conserved Rearrangement Relative To The Human Genome, N. L. Lòpez-Corrales, T. S. Sonstegard, T. P. L. Smith

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

The cytogenetic locations of the genes for protein C (PROC), transition protein 1 (TNP1), intestinal alkaline phosphatase (ALPI), engrailed (EN1), and human protointerleukin ß (IL1B) have been compared between cattle (Bos taurus, BTA) and sheep (Ovis aries, OAR). Bovine YAC and cosmid clones were used as FISH probes to determine the order (centromere to telomere) of four of these genes on OAR 2q, as well as the location of IL1B on OAR 3p. In cattle, IL1B and EN1 were assigned to BTA 11 and BTA 2, respectively. Alignment of the ovine, bovine, and human physical maps …