Digital Commons Network^™

Plant Resistance To Insect Herbivores: A Field Test Of The Environmental Stress Hypothesis, Svata M. Louda, Sharon K. Collinge

Svata M. Louda Publications

We tested the hypothesis that environmental stresses decrease overall plant resistance to insect herbivory in the field and evaluated biochemical mechanisms proposed to explain insect response to stressed plants. To impose a stress treatment, we severed lateral roots and rhizomes of a native crucifer (bittercress, Cardamine cordifolia) and quantified plant and herbivore responses for treatment and control clones. Severing roots and rhizomes once, early in the growing season: (1) produced moderate, but detectable, changes in plant physiological traits, specifically greater transient leaf water deficits at midday (P < .05) and elevated nitrate-nitrogen concentrations (P < .05); (2) altered plant quality, by causing an increase in soluble carbohydrates (P < .003), isoleucine concentrations in leaves (P < .01), and possibly glucosinolate concentration (P < .10), but made no differences in most primary nutrient concentrations, including total nitrogen, total free amino nitrogen, total amino acids, proline, and leaf water content; and (3) led to increased herbivore by chewing and leaf-mining (P < .001), but not by sap-feeding, insect herbivores. Trends toward decreased plant stature and fruit reproduction were not significant after 1 mo. In addition to the significant effect of our treatment, we found extensive variation in the magnitude of response to stress and herbivory among replicates. We hypothesize that environmentally induced physiological variation among plants within a plant population commonly distributes insect herbivore disproportionately onto a subset of the individuals, and in so doing influences the demography, distribution, and evolution of that plant population.

Historical Ecology As A Research Program, Daniel R. Brooks, Deborah A. Mclennan

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Modern evolutionary biology is the descendant of two theories proposed by Darwin. First, all organisms are connected by common genealogy, and second, the form and function of organisms is closely tied to the environments in which they live. Of these two theories, the role of the first (phylogeny) in evolutionary explanations has been diminishing in some fields, most notably in ecology and ethology. However, the last ten years have witnessed the beginning of a reversal in this trend. With increasing frequency, ecologists (Wanntorp et aI., 1990; Maurer and Brooks, submitted), ethologists (Dobson, 1985; Huey and Bennett, 1987; Mclennan et aI., …

Vertebral Pathology In Prehistoric And Historic Skeletons From Northeastern Nebraska, Karin L. Sandness, Karl J. Reinhard

Karl Reinhard Publications

Vertebral pathology has long been a useful criterion for anthropologists in the assessment of activity patterns, stress, and general health of extinct peoples. This method of analysis, however, has never been applied to the peoples of the Nebraska Great Plains. This study is the first to concentrate on the indigenous Native Americans of this region, examining the spinal pathology present in the prehistoric and historic skeletal remains. Pathology present in the form of spondylolysis, Schmorl's nodes, osteophytosis (degenerative disc disease), and osteoarthritis (degenerative joint disease), provides evidence to suggest differing activity patterns and levels of stress in Plains groups before …

The Effect Of Salinity On Spawning Frequency Of Penaeus Setiferus In Aquaria, John T. Ogle

Gulf and Caribbean Research

Penaeus setiferus were matured and spawned in a small 120L tank system in the absence of males. No significant differences in the number of shrimp that spawned or the time required to spawn were detected for shrimp held at salinities of 20, 25 or 30 ppt in either natural or artificial seawater. The earliest that spawning occurred was an average of 17 days past ablation and as late as 28 days past ablation. None of the shrimp held in artificial seawater at 20 and 25 ppt spawned in the same molt cycle in which they were ablated, while one third …

The Effects Of Ethanol On Cultured Serotonergic Neurons By Denise Kay Lokhorst., Denise Kay Lokhorst

Dissertations

No abstract provided.

A Preliminary Study Of Antibiotic Sensitivity Of Planktonic Bacteria From Cultures Of The Brine Shrimp Artemia Franciscana Kellogg, James R. Rosowski, Eugene D. Ayotte, Julie A. Peterson, Eugene L. Martin

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Great Salt Lake-biotype brine shrimp cysts were added to 440-1 saltwater cultures maintained at 20° ,25° , and 30° C. A micronized corn-byproduct was added each day as food. Planktonic bacteria found during growth of the brine shrimp were enumerated on Plate Count Agar (Difco). From the 25° and 30° brine shrimp cultures, a total of seven prevalent bacterial types (five gram-negative and two gram-positive) were isolated from throughout the 12-day growth cycle. Eight antimicrobial agents were tested against these bacteria, with chloramphenicol the most effective antibacterial agent overall, followed by erythromycin and carbenicillin. The bacterial density of the culture …

Factors Affecting Seasonal Dispersal Of The Tsetse Flies Glossina Pallidipes And G. Longipennis (Diptera: Glossinidae) At Nguruman, South-West Kenya, R. Brightwell, R. D. Dransfield, B. G. Williams

All Peer-Reviewed Publications

Seasonal changes in the distribution of the tsetse flies, Glossina pallidipes Austen and G. longipennis Corti, along a transect from riverine thickets out into open plains were monitored along with tsetse density, climatic factors, vegetation and host abundance. Dispersal of tsetse into open country was quantified using the mean spread. During and after the rains both species extended their distribution out into open country up to at least 3.5 km from riverine thicket areas. The mean spread of G. longipennis was greater than that of G. pallidipes. The spread of males and females was very similar, as was the spread …

Oviposition, Larval Arrest And Establishment Of Chilo Partellus (Lepidoptera: Pyralidae) On Maize Genotypes During Anthesis, Harish Kumar

All Peer-Reviewed Publications

The oviposition, larval arrest and establishment by the stem borer Chilo partellus (Swinhoe) were measured on different maize genotypes during anthesis. The maize genotypes tested were: Inbred A (Susceptible), Mp 704, MBR-8637, MBR-8650, MBR-8668, Poza Rica 7832, ER-29 SVR, Katumani Composite B, MMV 400, Bulk CG 4141, and ICZ2-CM. The moths oviposited on the middle leaves of the plant and the neonate larvae moved to leaf sheaths and ear husks to feed (arrest). As they grew older, the larvae invaded the stem, ear shanks and tassel to complete feeding (establishment) and to pupate. The response of the stem borer differed …

Disruption Of Glossina Morsitans Morsitans (Diptera: Glossinidae) Eclosion Behaviour: A Novel Method For Evaluating The Action Of Neurotoxic Agents, J. Ždárek, D. L. Denlinger

All Peer-Reviewed Publications

As the tsetse fly, Glossina morsitans morsitans Westwood extricates itself from the puparium and moves upward through the soil the ptilinum expands and contracts rhythmically and thus generates a stereotypic behavioural pattern that persists for up to 10 h if the tsetse fly remains confined. The response, which is easily recorded tensometrically from the movements of the ptilinum, can be exploited as a tool for evaluating the behavioral response of tsetse flies to various neurotoxic agents. The behavioural assay proves useful in providing precise information about the latency of the response and lethal time, and can suggest likely modes of …

Trypanosome Infection Rates In Tsetse Flies (Diptera: Glossinidae) And Cattle During Tsetse Control Operations In The Kagera River Region Of Rwanda, Steve Mihok, Leonard H. Otieno, Christopher S. Tarimo

All Peer-Reviewed Publications

Trypanosome infections were monitored in three species of tsetse fly (Glossina pallidipes Austen, G. morsitans centralis Machado, and G. brevipalpis News-tead) at four locations in the Kagera River region of Rwanda from May 1989 to September 1990. Two of the four areas (Mpanga Ranch and Bukora Ranch) were subjected to tsetse fly suppression operations with odour-baited traps. Proboscis infections of the Trypanosoma congolense and T. vivax types accounted for roughly equal numbers of the 207 mature infections detected (3.8%). Variation in infection rates was area-specific rather than tsetse species-specific. Order of magnitude differences in tsetse fly densities among areas were …

The Effects Of Ingested Carbonation On Oxygen Transport And Ventilation In Trained Distance Runners, Stacy Jean Ingraham

Dissertations and Theses @ UNI

The purpose of this study was to examine the effect of consumption of carbonated beverages on maximal aerobic capacity, as measured by maximal oxygen consumption (VO2MAX), and respiratory physiology, as measured by ventilation frequency (f), ventilatory equivalent for oxygen and carbon dioxide (O2VE, co2VE), expired minute ventilation (VE), carbon dioxide output (VCO2), respiratory exchange ratio (RER), and tidal volume (VT).

Thirteen male high school, collegiate and post collegiate distance runners from the local community performed two maximal treadmill tests exactly one week apart, following two different fluid ingestion treatments. The subjects were randomly assigned to a carbonated beverage or noncarbonated …

Coprolite Analysis: A Biological Perspective On Archaeology, Karl J. Reinhard, Baughn M. Bryant Jr

Karl Reinhard Publications

The most remarkable dietary remains recoverable from archaeological contexts are coprolites. Coprolites are desiccated or mineralized feces that are preserved in sheltered and open sites in arid regions, primarily in the New World. These dietary remains are remarkable from several perspectives. They typically contain a variety of macroscopic and microscopic remains that form interrelated data sets for the reconstruction of diets. Because contexts containing coprolites are typified by excellent preservation, the remains coprolites contain tend to be in better states of preservation than dietary remains recovered from nonfecal deposits. Coprolites also contain the well-preserved remains of intestinal parasites and pathogens …

Dan Canyon Burial: A Piii Burial In Glen Canyon National Recreation Area, Steve Dominguez, Karl Reinhard, Kari L. Sandness, Cherie A. Edwards, Dennis Danielson, F. A. Calabrese, Chris Kincaid

Karl Reinhard Publications

The Dan Canyon burial was discovered at a time when the philosophy, ethics, and legislation concerning the study of human remains are in a state of flux. A number of important sensitive issues germane to managers, archeologists, and American Indians are discussed in the introduction. The subsequent analysis provides a detailed scientific account of these remains and a glimpse of a segment of a people's past lifeway while remaining sensitive to the wishes of the American Indians.

The burial and associated grave goods of site 42SA21339 were exposed by wave action in a location frequented by boaters at the Glen …

Microphallus Fonti Sp. N. (Digenea: Microphallidae) From The Red Swamp Crawfish In Southern United States, Robin M. Overstreet, Richard W. Heard, Jeffrey M. Lotz

Harold W. Manter Laboratory of Parasitology: Faculty Publications

A new species of digenean, Microphallus fonti, is described from the red swamp crawfish in Louisiana, USA. It has a small pharynx and a rudimentary gut like M. opacus and possibly related species from crayfishes, but it differs from them by its relatively large male copulatory papilla and a conspicuous metraterm.

Development And Standardization Of A Short-Term Assay For Evaluating Polluted Estuarine And Coastal Environments: The Medaka Embryo-Larval Assay, Michael Frederick Helmstetter

OES Theses and Dissertations

The eggs of the Japanese medaka (Oryzias latipes) were employed in a number of studies to develop a routine, standardized assay which can assess the acute and sublethal impacts of individual toxicants and complex mixtures. The eggs of this Cyprinodont minnow were topically treated with each toxicant or mixture dissolved in membrane permeable dimethylsulfoxide (DMSO) solvent. Nine chemicals were initially evaluated with two, pentachlorophenol (PCP) and tributyltin chloride (TBTCl), subsequently selected for extensive evaluations of salinity tolerance and the accuracy of the topical exposure method for representing a typical immersion exposure. The amount of material actually penetrating the eggs was …

Mechanisms Mediating Sympathoadrenal Activation During Endotoxicosis In The Rat, Zhengzheng Zhou

Dissertations

No abstract provided.

Fodder Trees And Shrubs For High Rainfall Areas Of South Western Australia, Daya Patabendige, P R. Scott, Edward C. Lefroy

Resource management technical reports

In south Western Australia, the lack of good quality feed in late summer and autumn is a major constraint to livestock production. This feed gap is usually filled by costly supplementary hand feeding of grain or hay. The ability of some trees and shrubs to provide good quality forage during summer and autumn has generated interest for many years (Corbett, 1951; Everist, 1969; Snook, 1987;Oldham et al., 1991, Lefroy, 1991). The dual benefits of reducing the need for supplementary hand feeding and deferring the grazing of annual pastures until they are well established has recently led to the recognition of …

The Effect Of Canteen Menu On Nutritional Knowledge, Attitudes And Behaviour Of Year Five Students, Sharon Mcbride

Theses: Doctorates and Masters

Eating habits are learned during childhood, and patterns of behaviour established in childhood have important health ramifications throughout life. Over half of all deaths in Australia are linked to diet with over-consumption of saturated fat, sugar and salt, and lack of fibre being identified as particular problem areas. Nutrition education is an important component of primary health education curricula, and yet school canteens, and integral part of the school environment, do not necessarily offer healthy food choices that support nutrition instruction in the classroom. This study investigated the effect of canteen menu on student knowledge and attitudes toward nutrition and …

Impacts Of Types On Feed And Market Requirements, Donald L. Boggs

South Dakota Beef Seedstock Symposium, 1991

So you want to make them bigger! Or, do you want to add some milk to your cow herd? Improvements in these and other traits offer opportunities to increase production through higher weaning weights. However, the increased outputs are accompanied by increased feed and management inputs. Available research indicates that the increased production may or may not outweigh the increased inputs. Mature cow size and level of milk production are typically the factors considered when changes in cattle type are discussed. Numerous research studies have been conducted to evaluate the effects of these factors on biological and economic efficiency. In …

Current Status Of National Cattle Evaluation Programs For Carcass Traits, Larry Benyshek

South Dakota Beef Seedstock Symposium, 1991

At present, diet conscious consumers are exerting considerable pressure on the beef industry. Consumers continually indicate they are concerned about, and in fact, will not tolerate fat associated with red meat products (Breidenstein, 1988). This has resulted in many retailers trimming various cuts of beef to 1/8 inch of subcutaneous fat and in some cases a complete trimming of fat. It is probably conservative to estimate the industry produces an excess of 500 million pounds of fat each year from those carcasses with a yield grade above two. This excess fat represents the nutritional energy in more than a million …

Establishing Genetic Lines For Goal Oriented Buyers, Richard Janssen

South Dakota Beef Seedstock Symposium, 1991

No abstract provided.

Computations Associated With National Beef Cattle Evaluation Programs, Larry Benyshek

South Dakota Beef Seedstock Symposium, 1991

In 1971-72 the first U.S. National Sire Summary was published by a beef cattle breed association. At that time the idea of extending beef performance records into a national progeny testing program was indeed revolutionary. Until 1972, truly accurate comparisons of bulls could only be made within a herd-year-season contemporary group. The first and subsequent National Sire Summaries compared bulls across herds and/or generations.

Northeast Research Station Watertown, South Dakota Annual Progress Report, 1991, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1991 annual progress report for the Northeast Research Station in Watertown, South Dakota. This report is issued by the South Dakota Agricultural Experiment Station and the South Dakota State University Plant Science Department. This report includes information on the 1991 crop season, including precipitation data, grain and crop research, breeding, and variety testing, soybean row space study, weed control studies and cost, crop performance test, 1991 crop yields system productivity from 1985-1991, plant nutrition, soil test and research, profitability comparisons for farming system trials, weed populations.

Calving Difficulty In Beef Cattle: Part I, Harlan D. Ritchie, Peter T. Anderson

South Dakota Beef Seedstock Symposium, 1991

Calving difficulty (dystocia) can increase calf losses, cow mortality, and veterinary and labor costs, as well as delay return to estrus, and lower conception rates. In two studies at the U.S. Meat Animal Research Center (MARC), Clay Center, Nebraska, calf losses within 24 hours of birth averaged 4 percent for those born with little or no assistance compared to 16 percent for those requiring assistance. Calf mortality increased by a 0.35 percent per pound increase in birth weight. In a Hereford herd at the U.S. Livestock and Range Research Station. Miles City, Montana, 57 percent of all calf losses were …

Calving Difficulty In Beef Cattle: Part Ii, Harlan D. Ritchie, Peter T. Anderson

South Dakota Beef Seedstock Symposium, 1991

Many cattlemen believe reducing dietary energy during late pregnancy will decrease fetal size resulting in improved calving ease, whereas increasing energy will increase fetal size leading to a higher incidence of dystocia. Generally speaking, research has shown that lowering the energy allowance will decrease birth weight but will not significantly reduce dystocia. At MARC, Hereford and Angus 2-year-old heifers were fed three levels of energy (10.8, 13.7 or 17 .0 lb TDN/head/day) for 90 days prior to calving. Increasing the level of dietary energy resulted in increased birth weight but not increased dystocia; in fact, the incidence of calving difficulty …

Which Cows Are More Efficient, D. M. Marshall

South Dakota Beef Seedstock Symposium, 1991

On the surface, the topic of cow efficiency may seem to be primarily of importance to commercial cow-calf producers. The topic is also of importance to seedstock producers, because the primary purpose of the seedstock industry is to provide genetic resources for the commercial industry. It is critical that seedstock producers develop a good understanding of the challenges faced by commercial producers in order to provide the best possible services. Feed costs for the cow herd represent the single largest expense in producing retail beef. The proportion of total energy utilized in beef production that is required to support the …

Beef Cattle National Genetic Evaluation Programs, Larry Benyshek

South Dakota Beef Seedstock Symposium, 1991

Selection alters the frequency of genes in a population (breed) affecting a particular characteristic. Population genetic change is difficult for breeders to understand because they deal with individuals when making selection decisions and in their merchandising programs. Nevertheless, breeds (populations) which practice intense selection for characteristics of economic importance to the cattle industry will change genetically and eventually be the successful populations because they will leave the most progeny in the next generation. The genetic improvement of a population (breed) cannot overlook the individual because the individual, if selected, is the vehicle containing the genes which are to be passed …

1991 South Dakota Beef Seedstock Symposium, December 13-14, 1991, Department Of Animal And Range Sciences, South Dakota State University

South Dakota Beef Seedstock Symposium, 1991

This is the complete publication of presentations from the 1991 South Dakota Seedstock Symposium held on December 13-14, 1991 at South Dakota State University, Brookings.

Crossbreeding Systems And The Theory Behind Composite Breeds, James A, Gosey

Range Beef Cow Symposium

Crossbreeding serves the beef cattle industry as a tool to improve productivity through heterosis (hybrid vigor) and through complementarity (combining different breed strengths) to match genetic resources to various feed resources, climates, management levels and markets. Commercial cattlemen need to understand the principles of crossbreeding so they can adapt crossbreeding to their specific environment and needs. Seedstock breeders must be able to intelligently advise their commercial customers and know where their seedstock best fits into crossbreeding programs. Cattlemen today can be much more sophisticated in their approach to using crossbreeding. They realize many of the crossbreeding mistakes of the past …

Matching Cattle Nutrient Requirements To A Ranch’S Forage Resource, Or “Why We Calve Late”, Gregg Simonds

Range Beef Cow Symposium

Our goal at Deseret Land and Livestock is to maximize long-term profit. Our profit is a function of the following factors: the prices we receive for our production, our amount of production, the costs of production, and the productive capabilities of our land and labor. Prices, production, and cost are managed on an annual basis. The long-term outcome of one’s management is determined by their attention and skill in enhancing the capability of land and labor.

These factors of profit can vary tremendously within and between years. For example, prices for 400-500 pound steer calves from 1979-1989 varied nearly $.58/pound …