Life Sciences Commons^™

Tillage And Fertilizer Influences On Corn And Legume Cover, J. E. Gilley, J. F. Power, P. J. Reznicek, S. C. Finkner

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

The use of legumes in a cropping system may provide a variety of benefits. In this study, the effectiveness of selected legume species in providing surface cover was examined. The legumes were interseeded into either conventional or no-till corn, with or without N fertilizer. Both maximum legume cover and maximum cover furnished by corn plus legumes were examined. Mean cover provided during the study period by both the cover crop, and corn plus cover crop was also determined.

Can Genetically Engineered Crops Become Weeds?, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

There are significant differences if the distribution of weedy characteristics among weeds, normal plants, and crops. The world’s most serious weeds possess on the average 10 or 11 of these characters, a random collection of British plants have an average seven of the traits, and crop plants only five. For the average crop to become as “weedy” as the average weed, it would need to acquire five weedy traits. Even using the unlikely assumption that those traits are single loci in which a dominant mutation would provide the weedy character, this would require the simultaneous acquisition of five gene substitutions. …

Soil Disturbance-Residue Management Effect On Winter Wheat Growth And Yield, Wallace Wilhelm, H. Bouzerzour, J. F. Power

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

The need to reduce soil erosion, maximize soil water conservation, and optimize grain production in dryland cropping systems in the Central Great Plains has culminated in development of nontilled fallow systems. These systems have greatly reduced the degree of soil disturbance, and the amount and degree of residue incorporation. The objectives of this study were to evaluate the influence of soil disturbance and residue management on soil temperature, soil water, and winter wheat (Triticum aestivum L.) growth. Two field studies were established in 1981 and 1982 on an Alliance silt loam (Fine-silty, mixed, mesic Aridic Argiustoll) with treatments consisting …

A Comparison Of Chemical Composition & Fermentation Patterns Of Alternative Silages To Whole Plant Corn Silage, Susan Fox

Masters Theses & Specialist Projects

A comparison of the relationship of fermentation to chemical composition was made for forages which were wilted and ensiled at 35 to 45 percent dry matter. Trial I consisted of three forages ensiled in October, 1981: interseeded soybeans and grain sorghum. whole plant corn with added anhydrous ammonia, and whole plant corn with shelled corn added at a rate of 150 kg/t of fresh forage. Trial II consisted of two forages ensiled in 1982: interseeded soybeans and pearlmillet, and wheat. Temperatures of fermentation were collected, and chemical composition during the first 25 days of fermentation analyzed.

Production data were also …

Isolation & Characterization Of A Type I Topoisomerase From The Hypocotyls Of Etiolated Soybeans, Rick Dye

Masters Theses & Specialist Projects

Topoisomerases are enzymes of critical biological significance. Despite this fact, little data specific to the topoisomerases of higher plants has been published. This research was undertaken to isolate and characterize a higher plant topoisomerase from soybean hypocotyls to further the understanding of the structure and function of these enzymes.

Nuclei were isolated from frozen hypocotyls of 4 day old etiolated soybeans by homogenization and centrifugation, then lysed by gentle stirring in the presence of 1.5 mM ammonium sulfate. The resultant extract was desalted and purified by column chromatography on DEAF sepharose, 5-200 sephacryl and CM cellulose. The components of the …

Phosphorus Fertilization Through Drip Irrigation, Robert Mikkelsen

Robert Mikkelsen

Although P fertilization through drip irrigation systems has not been widely recommended, a review of currently available literature indicates this fertilizer application technique can offer many advantages when performed properly. Using drip irrigation to apply P fertilizer allows nutrient placement directly into the plant root zone during critical periods of nutrient demand. Less P fertilizer is generally required to achieve sufficient tissue P concentrations and equivalent yields when it is drip-applied than with other application methods. The distribution of drip-applied P in soil depends on soil properties, the source of P fertilizer, the rate of application, and the amount of …

Factors Affecting Selenium Accumulation By Agricultural Crops, Robert Mikkelsen, Albert L. Page, Frank T. Bingham

Robert Mikkelsen

The accumulation of selenium by plants is of concern worldwide. Many regions grow crops that contain insufficient Se to meet animal nutritional requirements. In these locations with low Se, efforts have been made to increase tissue Se concentrations. Other areas have problems with excessive Se found in vegetation grown on seleniferous soils. Plant species vary in their ability to accumulate and tolerate Se. Selenium accumulator plants can accumulate extremely high Se concentrations (several thousand mg Se kg-1) when grown in seleniferous soils, whereas typical agricultural crops have a much lower Se tolerance (<50 mg Se kg>-1 ). It has been suggested that …

Sheep Preference For Perennial Glandular-Haired And Eglandular Medicago Populations, Andrew W. Lenssen, E. L. Sorensen, G. L. Posler, L. H. Harbers

Andrew W. Lenssen

Erect glandular-haired Medicago species and hybrid populations have been developed that possess a high degree of resistance to the alfalfa weevil [Hypera postica (Gyllenhal)] and potato leafhopper [Empoasca fabae (Harris)]. Trials were conducted at the North Agronomy Farm, Manhattan, KS, in June and August 1986 to determine if erect glandular hairs on diverse perennial Medicago populations affect forage preference of sheep (Ovis aries). Glandular-haired (+) and eglandular (−) populations were selected from each of the following: diploids M. prostrata Jacq. and M. glandulosa David (KS94) and tetraploids M. glutinosa Bieb. (KS108), M. sativa L. ✕ M. prostrata (KS159), and M. …

Immune, Growth And Carcass Responses Of Ram Lambs To Active Immunization Against Desulfated Cholecystokinin (Cck-8), W. E. Trout, J. C. Pekas, B. D. Schanbacher

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

This study explored feed intake and carcass responses to active immunization against desulfated cholecystokinin-octapeptide (CCK-8) in ram lambs. Antibody titers 8 wk following primary immunization and booster immunizations given at 4 and 6 wk averaged greater than 1:1,000. Titers increased to greater than 1:10,000 by 16 wk following a final booster immunization at 11 wk. The antibodies developed against desulfated CCK-8 exhibited 29% and 13% cross-reactivities for sulfated CCK-8 and gastrin-17, respectively. Immunization against desulfated CCK-8 had no effect on feed intake, ADG, carcass weight or carcass quality grade. Backfat thickness and carcass yield grade were reduced (P < .05) by immunization. Organ weights at slaughter, including those of the pancreas and small intestines, were not affected by CCK-8 immunization, with the exception of the lungs, which were 16% lighter (P < .01) in immunized lambs. In conclusion, active immunization against desulfated CCK-8 resulted in development of high antibody titers against desulfated and sulfated CCK-8. Immunization against CCK-8 decreased fat content of the carcass but failed to affect feed intake, carcass weight or ADG.

Farming Systems Research/Extension And The Concepts Of Sustainability, Charles A. Francis, Peter E. Hildebrand

Department of Agronomy and Horticulture: Faculty Publications

Farming Systems Research and Extension (FSR/E) has strongly influenced the direction of agricultural development over the past two decades. Involving farmers, change agents and researchers, this participatory approach to technological improvement has evolved as an efficient means to develop individual components and more integrated systems that are uniquely suited to specific biophysical and socioeconomic conditions. Farmers with similar conditions and for whom specific recommendations are appropriate are grouped, in FSR/E, into identifiable Recommendation Domains. The technologies recommended conform with the biophysical and socioeconomic constraints that create environments within the domains, based on the philosophy that new technologies must conform with …

Concetta Tm (Papconc) C.V. (Rose Plant), Ellen T. Paparozzi

Department of Agronomy and Horticulture: Faculty Publications

A new and distinct variety of rose plant of the hybrid tea rose class, which was originated as a sport of the rose Gabriella; characterized by its bright orange red, well-formed hybrid tea type blooms with dark velvet overtones on the outer edges of the open flower; disease resistant with everblooming habit and outstanding pot forcing characteristics.

Blueberry Advisory Committee Research Report, H Y. Forsythe Jr, Judith A. Collins, David Lambert, John M. Smagula, Tom Degomez, Susan Erich, Mike Goltz, Joan M. King, Rodney J. Bushway, Alfred A. Bushway, Paul R. Hepler, David E. Yarborough, Delmont C. Emerson, Michele Marra

Wild Blueberry Research Reports

The 1988 edition of the Blueberry Advisory Committee Research Reports was prepared for the Maine Wild Blueberry Commission and the University of Maine Wild Blueberry Advisory Committee by researchers with the Maine Agricultural Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include:

1. Monitoring methods, economic injury levels, and action thresholds for blueberry spanworm larvae in vegetative year fields.

2. Control of secondary blueberry pests

3. Control of blueberry maggot

4. Effect of pruning practices on blueberry insect abundance

5. Survey of Fungi Contaminating Lowbush Blueberries

6. Nutrition Survey 1988

7. …

The Development And Failure Of Historic Agricultural Communities Of Utah: A Case Study Of Johns Valley, Utah, Wayne R. Shelley

Theses and Dissertations

Many agricultural communities have developed in Utah since the first settlement, but many no longer exist today. Some of these early communities experienced a "boom and bust," while others struggled for several years and were eventually abandoned. Johns Valley is a good example of these historic communities, as it experienced rapid growth and times of success and prosperity, yet it struggled and was eventually abandoned.
The situation in Johns Valley, from its early settlement to its demise, demonstrates the hope of the people who settled there and their efforts to make Johns Valley a productive and successful area. History also …

Texture, Climate And Cultivation Effects On Soil Organic Matter Content In U.S. Grassland Soils, Ingrid C. Burke

Ingrid Burke

Soil organic C content, a major source of system stability in agroecosystems, is controlled by many factors that have complex interactions.The purpose of this study was to evaluate the major controls over soil organic carbon content, and to predict regional patterns of carbon in range and cultivated soils. We obtained pedon and climate data for 500 rangeland and 300 cultivated soils in the U.S. Central Plains Grasslands, and statistically analyzed relationships between C and soil texture and climate. Regression models of the regional soils database indicated that organic C increased with precipitation and clay content, and decreased with temperature. Analysis …