Agricultural Science Commons^™

Response Of Leafy Spurge To Date Of Burning, Robert A. Masters

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

The research was conducted on remnant tallgrass prairie located in Lancaster County, Nebraska in 1990. Plots (5 by 10-m) were not burned or burned on either April 23, May 2, May 14, or May 26, 1990. Leafy spurge stem density and yield and yield of associated herbaceous vegetation were determined in July 1990 to assess response of the grassland community to prescribed burning treatments. Burning in late April through mid-May stimulated leafy spurge stem production. Density of leafy spurge stems in plots burned by mid-May significantly exceeded (P<0.04) the stem density in plots burned at the end of May. Leafy spurge stem density in plots burned the first week in May averaged 84 stems m^-2 as compared to only 27 stems m^-2 in plots burned …

Bulletin 4270 - Meat Quality In Beef Cattle, Brian Mcintyre

Bulletins 4000 -

Meat quality is the sole concern of the consumer once the product reaches the supermarket shelf. Breeding, feeding or any other factors that may have been important to the beef producer have no influence over the buyer's choice. Meat quality can be divided into two components — appearance and eating quality.

Colony Isolation And Secondary Culture Of Fetal Porcine Hepatocytes On Sto Feeder Cells, Neil C. Talbot, Vernon G. Pursel, Caird E. Rexroad Jr., Thomas J. Caperna, Anne M. Powell, Roger T. Stone

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

The secondary culture of non-transformed parenchymal hepatocytes has not been possible. STO feeder cell-dependent secondary cultures of fetal pig hepatocytes were established by colony isolation from primary cultures of 26-d fetal livers. The liver cells had the typical polygonal morphology of parenchymal hepatocytes. They also spontaneously differentiated to form small biliary canaliculi between individual cells or progressed further to large multicellular duct-like structures or cells undergoing gross lipid accumulation and secretion. The secondary hepatocyte cultures expressed alpha-fetoprotein (AFP), albumin, and β-fibrinogen mRNA, and conditioned medium from the cells contained elevated levels of transferrin and albumin. STO feeder cell co-culture may …

Effect Of The Conceptus And Lack Of Effect Of Uterine Space On Endometrial Protein Secretion During Mid-Gestation In Swine, Jeffrey Vallet, Harold Klemcke, Ronald Christenson

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

The effect of the conceptus and of reduced uterine space on endometrial protein secretion was examined on Days 40, 60, and 80 of gestation in white crossbred gilts. Twenty-nine gilts were checked daily for estrus, and 15 were given 5 mg estradiol valerate daily from Days 11 to 15 (Day 0 = day of estrus) of the estrous cycle to induce pseudopregnancy. The remaining 14 pigs were mated during estrus. All pigs were laparotomized on Day 4, and one uterine horn was ligated to produce one crowded and one roomy uterine environment. Pigs were killed on Days 40, 60, and …

Purification Of The Major Soybean Leaf Acid Phosphatase That 1s Increased By Seed-Pod Removal, Paul E. Staswick, Chuck Papa, Jing-Feng Huang, Yoon Rhee

Department of Agronomy and Horticulture: Faculty Publications

Fruit removal for 5 weeks after flowering increased acid phosphatase activity 10-fold in soybean (Glycine max 1. Merr. vai Hobbit) leaves compared with normal seed-pod-bearing plants. The major acid phosphatase activity in leaves was purified over 2700-fold, yielding a single polypeptide of 51 kD with a specific activity of 1353 units/mg protein using p-nitrophenylphosphate as the substrate. lsoelectric focusing demonstrated that the purified protein co-migrated with a majority of the activity that increased in leaves following seed-pod removal. lmmunoblot analysis demonstrated that at least part of the increased activity was dueto an increased abundance of the phosphatase protein. In situ …

Cdna Sequence For The Ribulose 1,5 Bisphosphate Carboxylase/Oxygenase Complex Protein A Protein That Accumulates In Soybean Leaves In Response To Fruit Removal, Paul E. Staswick, Steven J. Crafts-Brandner

Department of Agronomy and Horticulture: Faculty Publications

Soybean (Glycine max L.) transiently accumulates two abundant vegetative storage proteins, VSP A and VSP B, in vacuoles of above-ground vegetative tissues (Wittenbach, 1983; Staswick, 1990). As older leaves and stems become a source of exported metabolites for developing sinks, the VSPs are preferentially degraded and the resulting metabolites are presumably mobilized in the xylem and phloem stream. A striking feature of these proteins is that VSP gene expression is dramatically increased in mature leaves following the remova1 of reproductive sinks (seed pods) and the amount of these proteins increases accordingly (for review, see Staswick, 1994). Other changes …

Models To Predict Yield Loss Due To Weeds In Rice Ecosystems, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Yield loss models have been developed and evaluated for irrigated rice ecosystems with respect to effects of Echinochloa crusgalli. Simple regression models that give the relation between yield loss and weed density or relative leaf area are discussed with respect to their practical value in weed management in rice. More complex eco-physiological process models have been developed and used for rice ecosystems as well. Such models can be useful as a tool in research, whereas more simple approaches are needed for practical application in weed management.

Two-Dimensional Transport Model For Variably Saturated Porous Meda With Major Ion Chemistry, Jiří Šimůnek, Donald L. Suarez

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

We present the development and demonstrate the use of the two-dimensional finite element code UNSATCHEM-2D for modeling major ion equilibrium and kinetic nonequilibrium chemistry in variably saturated porous media.  The model is intended for prediction of major ion chemistry and water and solute fluxes for soils under transient conditions.  Since the solution chemistry in the unsaturated zone is significantly influenced by variations in water content, temperature, and CO₂ concentrations in the soil gas, all these variables are also calculated by the model.  The major variables of the chemical system are Ca, Mg, Na, K, SO₄, Cl, NO …

Fate Of Fluorescent Stained Sperm Following Insemination: New Light On Oviducal Sperm Transport And Storage In The Turkey, Murray R. Bakst

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

A novel approach was used to evaluate the distribution of sperm in the oviduct of turkey hens inseminated before or after the onset of egg production. Prior to insemination, sperm were stained with the nuclear fluorescent stain bisbenzimide. Sperm distribution in the sperm storage tubules (SST) of the uterovaginal junction and the infundibular tubular glands was determined by use of simultaneous differential interference contrast and fluorescence microscopy. In hens inseminated and examined prior to the onset of egg production, 94% of the SST contained sperm (21% were filled). In contrast, in hens inseminated initially before the onset of egg …

A Continuous Culture Of Pluripotent Fetal Hepatocytes Derived From The 8-Day Epiblast Of The Pig, Neil C. Talbot, Caird E. Rexroad Jr., Anne M. Powell, Vernon G. Pursel, Thomas J. Caperna, Sherry L. Ogg, Neil D. Nel

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

Continuous cultures of pluripotent prenchymal hepatocytes were derived from the epiblasts of 8-day-old pig blastocytes. The cells were polygonal and had phase-contrast dark, granular cytoplasm with prominent nuclei and nucleoli. These feeder-dependent cell cultures differentiated into large, multicellular, secretory, duct-like structures or formed small canaliculi between individual cells. Alternatively, the cells accumulated droplets that stained intensely with Oil Red O, a lipid-specific stain. Alpha-fetoprotein (AFP), albumin, and β-fibrinogen mRNAs were expressed as the cells differentiated in culture. Serum-free medium that was conditioned by the cells contained transferrin, AFP, and albumin. The growth and viability of the cells were inhibited by …

Repellency Of Aqueous Solutions Of Boric Acid And Polybor 3 To House Flies (Diptera: Muscidae), Jerome Hogsette, Philip Koehler

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

Mixed-sex 3- to Sod-old adult house flies, Musca domestica (L.), were exposed in nonchoice, choice, and consumption tests to increasing levels of boric acid and polybor formulated in 10% sucrose to test for repellent effects. Results of nonchoice and choice tests suggested repellency to high levels of both borates. Consumption decreased at levels >2.25% boric acid and 3.0% polybor, with approximate intake of 0.102 and 0.161 mg of boron, respectively. Our results indicate that 2.25% boric acid and 3.0% polybor are optimal treatment levels.

Comparative Germination Of Smooth Brome And Plains Rough Fescue, Perry L. Grilz, James T. Romo, James A. Young

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

Smooth brome (Bromus inermis Leyss.) is an aggressive invader of fescue prairie; however, little information is available on the germination ecology of this exotic perennial relative to native flora. This information is needed to understand the processes of invasion and to develop strategies to curb the spread of smooth brome. Germination of smooth brome and plains rough fescue (Festuca altaica subsp. hallii (Vasey) Harms) seeds was compared under various temperature regimes, levels of water stress, and light. Germination of both species was severely restricted by water stress, but not by temperatures between 5 and 25°C. Smooth brome had …

Interrelationship Among Chilo Partellus (Swinhoe) Damage Parameters And Their Contribution To Grain Yield Reduction In Maize (Zea Mays L.), S. O. Ajala, K. N. Saxena

All Peer-Reviewed Publications

Understanding the relationship among the spotted stem borer (Chilo partellus) damage parameters and grain yield reduction on maize (Zea mays L.) will aid in elucidation of the most important damage parameters that reduce yield, and may consequently lead to development of functional criteria to quantify tolerance and resistance. Correlations, stepwise multiple regressions and path coefficient analyses were used to study the interrelationship among the three damage parameters (foliar lesions, dead heart and stem tunnelling) and their contribution to grain yield reduction using three separate groups of genotypes in trials conducted between 1990 and 1991. Foliar lesions and stem tunnelling were …

Effects Of Neem Seed Derivatives On Brown Planthopper Symbiotes, S. Raguraman, R. C. Saxena

All Peer-Reviewed Publications

Populations of intracellular symbiotes declined significantly in brachypterous females of the brown planthopper, Nilaparvata lugens (Stål), which were stressed during nymphal development by caging them on IR20 rice plants treated with 3% neem oil, 5% neem seed kernel aqueous extract, or 10% neem cake aqueous extract. In addition, nymphs grew poorly and symbiote populations in prospective females declined, when reared on rice plants grown in soil treated with neem cake; this indicates systemic action of bioac-tive neem constituents. Addition of custard-apple oil to neem oil did not enhance the inhibitory effects. The effects of neem derivatives on the symbiotes may …

Distribution And Sampling Of Chilo Partellus (Lepidoptera: Pyralidae) In Maize And Sorghum On The Kenya Coast, W. A. Overholt, K. Ogedah, P. M. Lammers

All Peer-Reviewed Publications

The seasonal occurrence and spatial distribution of the crambine stem borer, Chilo partellus (Swinhoe) were investigated in maize, Zea mays, and sorghum, Sorghum bicolor, fields at the Kenya coast. During the vegetative growth stage, small-sized larvae were typically found behind leaf sheaths and in whorls in maize and sorghum. In reproductive and senescent maize, small-sized larvae were also found feeding in ears. Later immature life stages were located predominantly in stems in sorghum, and in the stems and ears in maize. Density and variance estimates of small, medium-, and large-sized larvae and pupae in maize and sorghum were fitted to …

Grain Yield Losses In Maize (Zea Mays L.) Genotypes In Relation To Their Resistance Against Chilo Partellus (Swinhoe) Infestation At Anthesis, Harish Kumar, Gershon O. Asino

All Peer-Reviewed Publications

Resistance/susceptibility of 12 maize genotypes to stem borer Chilo partellus (Swinhoe) (Lepidoptera: Pyralidae) was measured under artificial infestation at the time of anthesis during the short rainy seasons of 1989/90 and 1990/91. The maize genotypes tested were Inbred A (Kenya), Pwani hybrid (Kenya), Hybrid 511 (Kenya), ICZ2-CM (CIMMYT), MBR-8637 (CIMMYT), MBR-8650 (CIMMYT), MBR-8668 (CIMMYT), Poza Rica 7832 (CIMMYT), Mp704 (USDA), Katumani Composite B (Kenya), Bulk CG 4141 (Zambia), and MMV 400 (Zambia). Under low infestation (50-60 eggs per plant), the differences between susceptible and resistant genotypes in terms of stalk damage or grain damage were not apparent, whereas under high …

Bulletin 4265 - Termites, Peter Davis

Bulletins 4000 -

Termites are small, soft-bodied, social insects that feed on wood, grass, dead leaves, bark, humus, fungi or the dung of herbivore. They are commonly known as white ants, but are not related to true ants.

There are over 2300 species of termite of which about350 occur in Australia, and of these about 12 damage sound timber.

Bulletin 4272 - Growing Bananas In Carnarvon, Terry Hill

Bulletins 4000 -

The banana industry in Carnarvon began with small plantings. plantings in the 1940s. Since that time the industry has grown and become the mainstay of the region's horticulture industry.

In 1991, there were 360 ha planted to bananas and the industry was valued at $18.2 million. The major market for the crop is the Perth metropolitan area and Carnarvon remains the major supplier to this market. In recent years the development of a banana industry in Kununurra has resulted in increased competition, particularly in the winter months.

The industry is sited on land bordering the Gascoyne River, close to the …

Miscellaneous Publication 42/93 - Development And Dissemination Of Design Methods For Rangeland Paddocks Which Maximise Animal Production And Minimise Land Degradation, Shane Cridland, Mark Stafford Smith

Animal production and livestock published reports

Surveys of rangeland resources in Western Australia to date have shown that 23% of the area surveyed is in poor range condition. Poor condition is characterised by the loss of perennial vegetation allowing wind and water erosion. Approximately another 37% is in only fair range condition (Curry and Hacker 1990).

The loss of range condition is partly due to uneven use of paddocks by sheep and cattle. The areas close to water and the preferred pasture types are often over-utilised, while areas well away from water and less preferred pasture types are under-utilised. The result is that rangeland in good, …

Fractal Description Of Soil Fragmentation For Various Tillage Methods And Crop Sequences, Bahman Eghball, Lloyd N. Mielke, Guillermo A. Calvo, Wallace Wilhelm

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

Soil structure has been difficult to quantify and, at best, has been studied semiquantitatively. Fractal representation of soil fragmentation can provide an indication of soil structure. The purpose of our study was to use fractal analysis to quantify soil fragmentation under various tillage and crop sequence treatments at different times during the growing season. We collected soil samples from four tillage treatments (established 10 yr earlier) of chisel, disk, no-till, and moldboard plow in factorial arrangement with two crop sequences of corn (Zea mays L.)-soybean [Glycine max (L.) Merr.]-corn (C-SC), and soybean- cornaoybean, (S-C-S) on a Sharpsburg (fine, …

Bulletin 4267 - Growing Macadamia Nuts, John Dick, Alec Mccarthy

Bulletins 4000 -

The macadamia (Macadamia integrifolia and M. tetraphylla) are native Australian trees that have been developed as a commercial food crop.

About two million macadamia trees are planted in Australia over 6000 hectares. These produce about 12,000 tonnes of nuts. New South Wales and Queensland account for 90 per cent of the trees.

Unfortunately, Western Australian conditions are different again to the eastern States. Therefore, local trials will be required before varieties particularly suited to this State's conditions can be developed.

Residual Effects Of No-Till Crop Residues On Corn Yield And Nitrogen Uptake, M. S. Maskina, James F. Power, John W. Doran, Wallace Wilhelm

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

The residual effects of crop residues on N availability and crop growth are largely unknown. A field experiment was conducted from 1986 through 1988 at Lincoln, NE, to determine the residual effects on no-till corn (Zea mays L.) production and N uptake of 0,50, 100, and 1509'0 of the amount of crop residues produced by the previous crop during the previous 5 yr. These effects were evaluated with and without tillage (disking), N fertilizer (60 kg N ha^-1), and hairy vetch (Vicia villosa Roth ssp. villosa, 'Madison') winter cover crop. Increasing the previous crop residue …

Above-Ground Vegetative Development And Growth Of Winter Wheat As Influenced By Nitrogen And Water Availability, Wallace Wilhelm, Gregory S. Mcmaster, R. W. Rickman, Betty Klepper

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

Assessing the influence of nitrogen and water availability on development and growth of individual organs of winter wheat (Triticum aestivum L.) is critical in evaluating the response of wheat to environmental conditions. We constructed a simulation model (SHOOTGRO 2.0) of shoot vegetative development and growth from planting to early boot by adding nitrogen and water balances and response functions for seedling emergence, tiller and leaf appearance, leaf and internode growth, and leaf and tiller senescence to the existing wheat development and growth model, SHOOTGRO 1.0. Model inputs include daily maximum and minimum air temperature, rainfall, daily photosynthetically active radiation, …

Evidence For Volatile Male-Produced Pheromone In Banana Weevil Cosmopolites Sordidus, William J. Budenberg, Isaiah O. Ndiege, Florence W. Karago

All Peer-Reviewed Publications

Females of the banana weevil, Cosmopolites sordidus, were attracted to and made longer visits to live conspecific males, trapped volatiles from males, and dissected male hindguts in a still-air olfactometer. Male weevils were attracted to volatiles trapped from males and made longer visits to live males and volatiles from males. Live females, collected volatiles from females and female hindguts, elicited small or no behavioral responses from either sex. Electroantennogram (EAG) responses from both male and female antennae were elicited by collected volatiles from males and by dichloromethane extracts of male hindguts and bodies but not by surface washes of males. …

Proceedings Of The Workshop On Adaptation Of Plants To Soil Stresses, J.W. Maranville, V.C. Baligar, R.R. Duncan, J. M. Yohe

INTSORMIL Impacts and Bulletins

Sustainable production of food and forage with a focus on plant adaptation to stress environments will be a continued priority for developing countries in the future. Since many areas of the world which support substantial human populations are drought prone, such as the subsaharan African zone and others, the primary focus has been on drought. However, one of the greatest restraints to sustainability of agriculture worldwide is the lack of sufficient soil nutrients for crop growth, or other soil constraints such as acidity or salinity which hinder crop production substantially.

Optimizing soil fertility or amending acid and saline soils to …

Arkansas Rice Research Studies 1992, B. R. Wells

Arkansas Agricultural Experiment Station Research Series

The research reports in this publication represent one year of results; therefore, these results should not be used as a basis for longterm recommendations. Several research reports in this publication dealing with soil fertility also appear in Arkansas Soil Fertility Studies 1992, Arkansas Agricultural Experiment Station Research Series 425. This duplication is the result of the overlap in research coverage between the two series and our effort to inform Arkansas rice producers of all the research being conducted with funds from the rice check-off.

Scales: A Computer Program To Convert Among Three Developmental Stage Scales For Wheat, Dorothy M. Harrell, Wallace Wilhelm, G. S. Mcmaster

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

The Haun, Feekes, and Zadoks-ChanpKonzak developmental stage scales are often used to report phenological information for wheat (Triticum aestivum L.) development. Agronomists familiar with one of these scales may have only a passing acquaintance with developmental scales other than the one they consider most appropriate for their purposes. This makes review and interpretation of the literature more difficult. Although wheat development models often report phenological results, they generally use no more than one scale. For these reasons, and because there is not a simple numeric correspondence among the three scales, a computer program to convert among them is a …

Influence Of Microphytic Crusts On Selected Soil Physical And Hydrologic Properties In The Hartnet Draw, Capitol Reef National Park, Utah., John Dana Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microphytic crust influences on selected physical and hydrologic soil properties were examined at one location in Capitol Reef National Park, Utah. Designed experiments were conducted in a sandy loam soil where microphytic crusts were present without the concomitant development of confounding physical or chemical soil conditions. Three treatments were used for all experiments: control, chemically killed (microphytes killed but left in place), and scalped (microphytic crusts mechanically removed).

A portable wind tunnel was used to deter-nine if microphytic crusts contribute to soil stability and reduce the erosive effect of wind. Significantly lower threshold friction velocity and greater wind-entrained material were …

Proceedings Of The 20th Annual Meeting, Southern Soybean Disease Workers (March 28-30, 1993, Fort Walton Beach, Florida), Patrick D. Colyer, Glenn R. Bowers Jr., John C. Rupe, Brian M. Anderson, Glenn G. Hammes

Southern Soybean Disease Workers: Conference Proceedings

Contents

Sustainable agriculture symposium

Sustainable Agriculture and the Soybean Industry: Building a Winning Strategy. D Hubbard and MS Fitzner

Impact of Pest Interactions on Management Programs. J Funderburke

Introducing Procedures of Sustainable Agriculture, a Team Approach. J Bradley

Sustainable Agriculture Practices and Their Impact on Plant Diseases. C Rothrock

Graduate student competition

Effect of Increasing Initial Inoculum Levels of Rotylenchus reiformis on Soybean. JJ Cornelius and GW Lawrence

Effect of Frogeye Leaf Spot on Yield of Soybean Lines Near-Isogeneic for Resistance. PF Pace, DB Weaver, LD Flopper, and PA Backman

Heritability and Genotype X Environment Interaction of Partial Resistance to …

Comparison Of The Phosphate Requirements Of Burr Medic And Yellow Serradella With That Of Wheat In The Low Rainfall Wheatbelt Of Western Australia, Blakely Paynter, Mike D. Bolland

Grain and Other Field Crops Research Articles

The responses of burr medic (Medicago polymorpha) and yellow serradella (Ornithopus compressus) to topdressed phosphate were compared with the response of wheat (Triticum aestivum) to drilled phosphate on a range of soils in the low rainfall wheatbelt of Western Australia. Species were compared firstly on the amount of applied phosphorus (P) required for 90% maximum yield at 3 harvests, and secondly on the ratio of their curvature coefficients from the Mitscherlich relationship between absolute yield and P applied. On 7 marginally acidic, medium-textured soils, the comparative requirements of burr medic (cvv. Serena or Santiago) and wheat (cv. Gutha) for applied …