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Full-Text Articles in Life Sciences

Factors Affecting The Development Of Lipase Flavor In Butter, Lawrence I. Bell Jan 1975

Factors Affecting The Development Of Lipase Flavor In Butter, Lawrence I. Bell

Electronic Theses and Dissertations

Current trends in the dairy industry have resulted in an increase in the incidence of lipase flavored butter. Raw cream, fresh and aged 24 h, was divided into 3 fractions and heat treated at temperatures of 72 C, 85 C, and 93 C. Each fraction of cream was churned into butter, with the butter divided and stored at -28. 9 C and 4.4 C. Lipase flavor development was measured organoleptically, by acid degree value (ADV), and free fatty acids (FFA) using a colorimetric procedure. Age of the cream had a significant effect (P< .01) on FFA and. ADV .levels, whereas heat treatment .of the cream had a significant effect (P< .01) on flavor only. Storage time had a significant effect (P< .01) on FFA, ADV, and flavor and the temperature of storage had a significant effect (P< .01) on FFA ·and flavor. Correlation between FFA and ADV was 0.86. There was no correlation between flavor and either JTFA or ADV

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Cytopathology Of Barley And Corn Leaf Tissue Infected With The Nd18 Strain Of Barley Stripe Mosaic Virus, Charles R. Mcmullen Jan 1975

Cytopathology Of Barley And Corn Leaf Tissue Infected With The Nd18 Strain Of Barley Stripe Mosaic Virus, Charles R. Mcmullen

Electronic Theses and Dissertations

The distribution of the ND18 strain of barley stripe mosaic virus (BSMV) in barley (Hordeum vulgare L.) and corn (Zea mays L.) leaf tissue was studied with light and electron microscopes. Virions were detected in the cytoplasm of barley mesophyll cells, subsidiary, guard and epidermal cells, vascular parenchyma cells, sieve and tracheary elements. Nuclear virus was found in barley mesophyll cells. Ultrastructural cytopathological changes were greatest in the inoculated leaf of barley which contained fewer virus particles than either primary acute or chronically infected tissues. Primary acute and chronically infected barley tissues contained intracellular virions scattered in the cytoplasm, in …

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Amino Acid Additions To A Low Protein Corn-Soy Diet For Egg Production, Ali Baghaye Kashani Jan 1975

Amino Acid Additions To A Low Protein Corn-Soy Diet For Egg Production, Ali Baghaye Kashani

Electronic Theses and Dissertations

The present study was conducted to determine if the protein level of layer diets could be lowered from the: commonly used 16 percent to 12 percent by supplementation of some of the essential amino acids without reducing the performance of hens. The amino acids used were methionine, lysine, tryptophan and isoleucine. Egg production, egg shell thickness, interior egg quality, body weight, feed efficiency and free amino acid content of the albumen of eggs produced were criteria used to measure the (--) to treatment.

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Integrated Numerical Simulation Of Drip Irrigation With Subsurface Drainage, James Ray Hoover Jan 1975

Integrated Numerical Simulation Of Drip Irrigation With Subsurface Drainage, James Ray Hoover

Electronic Theses and Dissertations

A numerical method and model were developed to simulate soil moisture during steady-state and transient flow toward a tile drain. Intermittent application of water by drip irrigation and rainfall were simulated by use of finite difference approximation equations. No known analytical solution for these flow situations exists because of the complex mathematics describing unsaturated flow in the soil. The computer model is based on the electrical resistance network analog. The explicit finite difference equations were solved by the successive over-relaxation method for steady-state flow and by iteration for transient soil moisture flow. The computer program for the model consists of …

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Induction Of Parturition In The Ovine, Ernest L. Harman Jan 1975

Induction Of Parturition In The Ovine, Ernest L. Harman

Electronic Theses and Dissertations

The effects of flumethasone and prostaglandin F2 (PGF) on the time of parturition were studied in the ewe. Pregnant ewes with known conception dates were allotted into a 3 x 3 x 2 factorial designed experiment (1973 study) and into a completely random designed experiment (1974 study). In the 1973 study treatments consisted of three hormones (flumethasone, PGF and saline control), three levels (low, .5 mg flumethasone, 5 mg PGF, 1 cc saline; medium, 1.0 mg flumethasone, 10 mg PGF, 2 cc saline; high, 1.5 mg flumethasone, 15 mg PGF, 3 cc saline) and two routes of administration (IM …

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Effects Of Land Disposal Of Pulp Mill Effluents On Plant Nutrient Uptake And Element Balance, Joseph B. Schwarzback May 1974

Effects Of Land Disposal Of Pulp Mill Effluents On Plant Nutrient Uptake And Element Balance, Joseph B. Schwarzback

Electronic Theses and Dissertations

An analysis of the soil and plant tissues was undertaken to ascertain the effect that land irrigation with pulp mill effluent has on nutrient uptake and element balance of tree seedlings. Results show that the effluent significantly increased the sodium content of both soil and tissue; however, these levels fell far below the level necessary to become detrimental to plant life, soil chemistry and soil structure. There was evidence that the increase of elements from the effluent provided positive effects in growth and plant health. There was no evidence of sodium toxicity or calcium starvation. Evidence clearly points out the …

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Characterization Of A Bovine Parvovirus, Thomas J. Langpap Jan 1974

Characterization Of A Bovine Parvovirus, Thomas J. Langpap

Electronic Theses and Dissertations

Bovine parvovirus has been shown to produce calf scours (40). Although exact figures are unavailable, a sizeable economic loss is suffered annually by South Dakotans as a result of this disease. Bovine parvovirus has been isolated in South Dakota (7). However, the extent of exposure to the virus is unknown. The object of this study is to characterize the South Dakota parvovirus isolate and determine by serological methods the extent of exposure in cattle. A preliminary study to determine the ability of parvovirus to cause abortion in cattle will also be undertaken.

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Effects Of Fungus-Fermented Soybeans On Broiler Growth And Life Cycle Performance Of Coturnix Quail, Cheong Choo Chah Jan 1974

Effects Of Fungus-Fermented Soybeans On Broiler Growth And Life Cycle Performance Of Coturnix Quail, Cheong Choo Chah

Electronic Theses and Dissertations

Despite the extensive data that have accumulated on the detrimental effect of molds on the growth of farm animals, very little is known as to the beneficial role of fungi in animal feed. Recent studies at South Dakota State University research laboratories revealed, however, that only 164 of 392 strains of Aspergilli were found to be toxic. When the cultures were grown on sterile soybeans or wheat, some of the tested cultures exerted positive effects on growth of chicks and mice. Hence, the investigations reported herein were initiated to obtain further information on those cultures beneficial to chick performance and …

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Quantitative Gene Action And Interrelationships Of Protein Content With Some Metrical Traits Of Oats, Harbans Singh Sraon Jan 1974

Quantitative Gene Action And Interrelationships Of Protein Content With Some Metrical Traits Of Oats, Harbans Singh Sraon

Electronic Theses and Dissertations

The objectives of this study were (a) to determine gene action, heritability and number of effective factors controlling protein content in oats, (b) to investigate the interrelationships of protein content with other agronomic characters, and (c) to evaluate the feasibility of utilizing A. sterilis germplasm in oat breeding projects. Four genetically distinct cultivars with protein content ranging from 15.7 to 26.6 percent were crossed in all possible combinations to make a complete set of diallel crosses. The data suggested additive gene action and partial dominance for protein content. Groat percentage and number of panicles showed overall partial dominance. Yield and …

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In Vitro And In Vivo Evaluation Of Protecting Whey Protein Concentrate For Ruminants, David Rodriguez Maltos Jan 1974

In Vitro And In Vivo Evaluation Of Protecting Whey Protein Concentrate For Ruminants, David Rodriguez Maltos

Electronic Theses and Dissertations

In experiment I a series of in vitro buffer and rumen fermentation studies were conducted to evaluate protein solubility at pH 6.8 and pH 2.5 (with pepsin) and ammonia production from whey protein concentrates (WPC, 55% protein) treated with 0, .25, .5, 1.0, and 3% formaldehyde; 1, .5, 1.0, 2.0, 3.0, and 6% tannic acid; and 0, 1, 2, and 3 hr of heat treatment at 104 C. Protein solubility and ammonia production from casein treated with 0, .5, 1.0, and 3% formaldehyde and 0, .5, 1.0, and 3% tannic acid were also studied. All levels of formaldehyde treatment of …

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Initiation Of Parturition In Dairy Cows With Dexamethasone And Dexamethasone Plus Estradiol Benzoate, Gary Lee Beardsley Jan 1974

Initiation Of Parturition In Dairy Cows With Dexamethasone And Dexamethasone Plus Estradiol Benzoate, Gary Lee Beardsley

Electronic Theses and Dissertations

Parturition was initiated in 25 of 29 (Trial 1) and 26 of 26 (Trial 2) Holstein cows given dexamethasone (Trial 1), 4.4 mg/100 kg body weight, or dexamethasone plus .25 mg estradiol benzoate (Trial 2) at day 273 of gestation. Parturition occurred at 45.l z +/-11.1 h (Trial 1) and 40.8 ± 9.6 h (Trial 2) after injection. Twenty-nine control cows (Trial 1) and 26 control cows (Trial 2) had average gestation lengths of 280 and 281 days, respectively. In Trial 1, calving difficulty was greater (P <.05) while birth weight of calves was 3.0 kg less (P<.05) for the induced cows compared to controls. In Trial 2, no differences in calving difficulty were found, while calf birth weight was 2.5 kg less (P <.10) for the induced cows compared to controls. Average birth weights of calves were 42.4 and 45.4 kg, Trial 1; and L~o.8 and 43.3 kg for Trial 2, for induced and control groups. Severity of udder edema did not differ for either trial. Average daily milk production for the first 9 wk of lactation was 2l~.8 kg and 27.8 kg (Trial 1) and 24.2 kg and 27.7 kg (Trial 2), for induced and control groups. In both trials, differences in milk fat or fat corrected milk were nil. Total milk production (305 day-2X-mature equivalent) was not significantly different for either trial. Changes in body weight were similar for control and induced cows in both trials. The incidence of retained placental membranes was 76 and 10'/4 (Trial 1) and 50 and 4% (Trial 2) for induced and control cows. Average days to first heat, days to firs+, service, days to conception, and services per conception for induced cows were: 58 .4, 79-9, 117.8, 2.0 (Trial l); 80.7, 81.4, 102.2, 1.64 (Trial 2); and for control cows were: 58.6, 82.3, 105.5, 1.8 (Trial l); 89.0, 91.4, 128~6, 1.94 (Trial 2). In Trial 1, the incidence of milk fever in cows with no previous history was 24 and 10'/4 for induced a"'1.d control cows. There were no differences in the incidence of metabolic disorders in Trial 2. Results of California Mastitis Tests were similar for control and induced cows in both trials. In both Trial 1 and Trial 2, fat, protein, total solids, and gamma globulin content of the colostrum did not differ between control an treatment groups;· Casein values were lower (P <.05) for the treatment group in both trials. Average daily gains from 0 to 10 weeks were .63 and .60 kg, for Trial 1; and .51 and .46 kg, for Trial 2, for induced and control calves. No differences were found in calf death loss or health disorders between groups. Similar levels of serum gamma globulin were found for both groups at 0 (before sucking) and 3 days of age in both trials. No meaningful differences were found in total serum protein, albumin, and alpha and beta globulin levels in both trials. No differences were found at birth, in chest depth, shoulder width, head circumference, hip width, and wither height of calves.

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Parasites Of Salmonid Fishes From Southcentral Alaska, James Carl Riis Jan 1974

Parasites Of Salmonid Fishes From Southcentral Alaska, James Carl Riis

Electronic Theses and Dissertations

The importance of fish parasites is directly related to the value of the fish they affect. Alaskan salmonids are extremely important and are constantly increasing in value to the United States. Other countries, such as Japan and Russia, are also finding Alaskan salmonids important as a foodstuff. If human populations continue growing at present rates, in only a few years there could be twice as many people eating fish. As a recreational asset in Alaska, salmonids rank at or near the top, both for sportfishing and as a natural attraction. It is thus important from an economic point of view …

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Improving Water Use Efficiency Of Smooth Bromegrass By Selecting For Regrowth, Delmer F. Gross Jan 1974

Improving Water Use Efficiency Of Smooth Bromegrass By Selecting For Regrowth, Delmer F. Gross

Electronic Theses and Dissertations

Sixty-nine genotypes, including 60 from the variety Saratoga smooth bromegrass, three from South Dakota 7 smooth bromegrass, and two each of reed canarygrass, orchardgrass, and creeping meadow foxtail as check species were selected for regrowth from a source nursery containing over 37,000 genotypes. In addition, four genotypes of Saratoga with poor regrowth capability were selected as checks. These 73 genotypes were placed in a greenhouse environment to evaluate digestibility (IVDMD), and other characteristics. After three harvests, 34 genotypes were vegetatively propagated in a field experiment to determine regrowth capabilities. NCE rates were not correlated highly with yield in the greenhouse …

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Gonadal Hormone Levels Prior To And Following Puberty In Straightbred And Crossbred Beef Heifers, Walter Ronald Parker Jan 1974

Gonadal Hormone Levels Prior To And Following Puberty In Straightbred And Crossbred Beef Heifers, Walter Ronald Parker

Electronic Theses and Dissertations

Five heifers from each of four breed groups (Angus x Angus, Charolais x Charolais and the two reciprocal crosses) were used in a study of gonadal hormone levels during the interval from 16 weeks before puberty to puberty (trial I). Puberty was defined as the first standing estrus. Two heifer calves from dams from each of the above breed groups and sired by a single Polled Hereford bull were used in a study of gonadal hormone levels from birth to weaning (trial II). Blood samples were collected at weekly intervals from trial I heifers before puberty and three times weekly …

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Color And Light Intensity Preferences Of Four Species Of Alate Cereal Aphids, Donald A. Dickmann Jan 1974

Color And Light Intensity Preferences Of Four Species Of Alate Cereal Aphids, Donald A. Dickmann

Electronic Theses and Dissertations

Color and light intensity preferences of 4 species of alate cereal aphids, the English grain aphid, Macrosiphum avenae (Fab.); oat bird-cherry aphid, Rhopalosiphum padi (L.); corn leaf aphid, R. maidis (Fitch); greenbug, Schizaphis graminum (Rondani); were tested under controlled conditions. No significant differences in color response were found between post-teneral (flight-active) and flight-exhausted alates of any species. Macrosiphum avenae, R. maidis, and S. graminum showed a distinct preference for yellow; R. padi usually preferred green. Alates of all species preferred high light intensities to low within the range tested (350-3500 ft-c). Preferred colors (yellow and green) were more important than …

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The Effects Of Gestation Metabolizable Energy Levels On Sow Productivity And Hematology, George W. Libal Jan 1974

The Effects Of Gestation Metabolizable Energy Levels On Sow Productivity And Hematology, George W. Libal

Electronic Theses and Dissertations

It has been estimated that of the potential ova shed by the sow on1y about 55% result in live pigs born. Reproductive inefficiency can occur as a result of oversupplying or undersupplying energy. Since 1959, the National Research Council has reduced its listed energy requirements for the gravid sow considerably. The studies reported herein were conducted to evaluate metabolizable energy (ME) levels for gestating sows at and below the recommended levels and measure their effect on sow productivity as well as sow hematology at various stages of reproduction. Two experiments, each consisting of three trials, were conducted. Experiment 1, two …

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Corixidae (Water Boatmen) Abundance And Contribution To Littoral Zone Fish Forage In Lake Poinsett, South Dakota, Richard Lee Applegate Jan 1974

Corixidae (Water Boatmen) Abundance And Contribution To Littoral Zone Fish Forage In Lake Poinsett, South Dakota, Richard Lee Applegate

Electronic Theses and Dissertations

Corixids were sampled each week in littoral zone areas of Lake Poinsett during the open water seasons, April-October, in 1970, 1971, and 1972. Fish were sampled each week in littoral zone areas in 1970 and food habits studies were conducted to determine if fish predation would influence corixid population dynamics. Seven genera and 15 species of the family Corixidae were collected. Major indigenous species were Palmarcorixa buenoi Abbott, Trichocorixa borealis Sailer, Cenocorixa dakotensis (Hungerford), and Sigara conocephala (Hungerford). Species migrating to Lake Poinsett in the fall to overwinter were Sigara alternata (Say), S. solensis (Hungerford), S. bicoloripennis (Walley), Hesperocorixa vulgaris …

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Criteria For Recreation Site Selection On Flood Control Reservoirs-Case Studies, Kenneth B. Mclaughlin May 1973

Criteria For Recreation Site Selection On Flood Control Reservoirs-Case Studies, Kenneth B. Mclaughlin

Electronic Theses and Dissertations

Stephen F. Austin State University was awarded a contract in August 1971 to select the 1,200 acres best suited for recreation area development on three proposed flood control reservoirs. At that time, there was no central publication which could be used as a guide for such a project. This thesis was written to help correct this situation. The nine factors that were used in initial site selection are soils, topography, access, wind, vegetation, land ownership, distribution of the sites, bridges and open-water and cove locations. Once the sites were selected, they were evaluated and assigned priorities for development according to …

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Dried Whey As An Additive For Alfalfa Haylage And As A Grain Supplement For Dairy Cows, Sitakantha Dash Jan 1973

Dried Whey As An Additive For Alfalfa Haylage And As A Grain Supplement For Dairy Cows, Sitakantha Dash

Electronic Theses and Dissertations

This research was conducted to explore the possibility of utilizing surplus whey in dairy cattle rations. Four experiments determined the influence of whey on preservation, digestibility and feeding value of alfalfa haylage. The last experiment was initiated to evaluate dried whey as a grain supplement. When dried whole whey was added at O, 1, and 10% levels to reconstituted alfalfa haylage (chopped baled hay plus 50% water) and preserved in sealed metal containers, it reduced pH, decreased acetic acid, and increased lactic acid. The general pattern of fermentation was better in whey-treated haylages than in corresponding untreated haylages. An in …

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Partial Characterization Of Animal Growth Inhibitors From Soybeans, Joseph Richard Uckert Jan 1973

Partial Characterization Of Animal Growth Inhibitors From Soybeans, Joseph Richard Uckert

Electronic Theses and Dissertations

The pH 4. 4 supernatant from raw (unheated) soybean meal was separated into 5 fractions on a Sephadex G-25 column in efforts to isolate the animal growth inhibitors present soybeans. Each fraction was added to the diet of growing mice and growth inhibition (GI) activity was determined by comparing their_ growth rates to g1"'owth rates achieved on an autoclaved soybean meal diet. Fractions I and II each contained about 50% of the GI activity, with a trace in fraction III and none in fractions IV and V. Only fraction I contained trypsin inhibitor and caused pancreatic enlargement. Fraction I was …

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The Vitamin E Status Of Lactating Dairy Cows After Receiving Stored Feeds For 15 Months, Marc Dellhime Eckhart Jan 1973

The Vitamin E Status Of Lactating Dairy Cows After Receiving Stored Feeds For 15 Months, Marc Dellhime Eckhart

Electronic Theses and Dissertations

The trend in dairying in recent years has been towards more confinement housing and higher producing animals. Such confinement housing often leads to year-around feeding of stored feeds, such as silage, haylage, and hay with no pasture grazing or feeding of freshly cut forages. Since stored feeds contain substantially less vitamin E than those same forage when freshly cut or grazed, it may be important to re-evaluate the vitamin E status of cows fed stored feeds continuously. The requirement of cattle for vitamin E are largely unknown. The one study involving adult cattle, conducted 25 years ago, found that 1.82 …

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The Eriophyoidea Of South Dakota, Magdalena Lopez Briones Jan 1973

The Eriophyoidea Of South Dakota, Magdalena Lopez Briones

Electronic Theses and Dissertations

This paper presents the results of the taxonomic investigation of the Eriophyoidea in South Dakota. Information is given on the morphology, discussion of variation within a population, distribution, damage in host plants, economic importance and techniques of collecting and preparing specimens. There are 42 previously described species included in this study. Of the 48 species studied, six are new. Species described are: Aculops maximilianae, Diptacus pengsonae, Eriophyes arceosae, Eriophyes taylori, Tegonotus lindenus, and Tetra mcdanieli.

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A Study Of Energy And Water Transfer In Irrigated And Nonirrigated Sorghum, Loyd Raymond Stone Jan 1973

A Study Of Energy And Water Transfer In Irrigated And Nonirrigated Sorghum, Loyd Raymond Stone

Electronic Theses and Dissertations

Approximately 70% of all precipitation is lost through percolation out of the root zone or by evapotranspiration (evaporation from the soil plus transpiration from plants). Estimation of these water loss processes has generally been on a small scale due to the cost and time required for their measurement. Development of remote thermal scanners has provided a possible means of estimating water loss from surfaces by using the surface temperature. This study was designed (a) to determine water movement patterns in the soil profile and (b) to evaluate the feasibility of using canopy temperatures in estimating evapotranspiration rates from cropped areas. …

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The Role Of Nematodes In A South Dakota Grassland Ecosystem, James D. Smolik Jan 1973

The Role Of Nematodes In A South Dakota Grassland Ecosystem, James D. Smolik

Electronic Theses and Dissertations

In an attempt to elucidate the role of nematodes in a grassland ecosystem nematode taxa, number and biomass data was gathered over a three year period at the Cottonwood International Biological Program Grassland Biome site in western South Dakota. The effects of grazing intensity, sampling date and sampling depth were studied. Nematicide treatment of range grasses in field and greenhouse studies was also used to evaluate the role of nematodes. Biomass data was used to estimate the intake of plant feeding nematodes. Results obtained demonstrate that soil inhabiting nematodes constitute a significant proportion of the consumer biomass at the Cotton[1]wood …

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Biology Of The Flea Beetle, Altica Carduorum Guer. (Coleoptera: Chrysomelidae) On Canada Thistle, Cirsium Arvense (L.) Scop., In South Dakota, Burton Danis Schaber Jan 1973

Biology Of The Flea Beetle, Altica Carduorum Guer. (Coleoptera: Chrysomelidae) On Canada Thistle, Cirsium Arvense (L.) Scop., In South Dakota, Burton Danis Schaber

Electronic Theses and Dissertations

A laboratory colony of Altica carduorum Guer. was established from a stock colony of 50 adult beetles. They had an average previposition period of 7 days when exposed to a regular cycle of 16 hr. of light (24° C) and 8 hr. of darkness (12.75° C). Under these conditions, females laid an average of 259.3 ± 9.7 eggs, and longevity averaged 100 days. The eggs are laid on the underside of leaves along edges of leaf veins throughout June. Adults fed and overwintered in the soil, and some beetles emerged the following spring and laid viable eggs. Laboratory studies indicate …

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Growth, Development, And Plant Temperature Characteristics Of Oats Under Water Stress, Bikkar S. Sandhu Jan 1973

Growth, Development, And Plant Temperature Characteristics Of Oats Under Water Stress, Bikkar S. Sandhu

Electronic Theses and Dissertations

Little information is available on sensitivity of oats to water deficits. Therefore, this study was designed (a) to investigate physiological response of oats to water stress, (b) to determine quantitative effect of water deficits on growth and yield components of oats, and (c) to evaluate plant temperature of oats as a water stress index. Spring oats (Avena sativa L.) grown under field conditions were subjected to 10-11 day stress at boot stage, at anthesis through early grain formation stage and at both stages in combination. Diurnal and seasonal patterns of relative leaf water content, leaf diffusion resistance, and net photosynthesis …

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Application Of 125i To The Detection And Assay Of Viruses And Viral Antibody Adsorbed To Latex Particles, Charles Steven Duvall Jan 1973

Application Of 125i To The Detection And Assay Of Viruses And Viral Antibody Adsorbed To Latex Particles, Charles Steven Duvall

Electronic Theses and Dissertations

This study, then, was undertaken to develop a universal, in vitro, extracellular method utilizing fluorescence and radioactive 125I to rapidly detect, identify, and quantitate pathogenic viruses and viral antibodies. Focus of the study is the CLAM model, which consists of inert latex particles, plus four radioactively labeled components: antibody, virus, enzyme (RNase) and fluorochrome (FITC).

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Evaluation Of Bi-Level Drainage Theory With A Viscous-Flow Analog, James Marfred Kienholz Jan 1973

Evaluation Of Bi-Level Drainage Theory With A Viscous-Flow Analog, James Marfred Kienholz

Electronic Theses and Dissertations

The primary purpose of this study is to evaluate the validity of this bi-level theory with a viscous-flow analog. Viscous-flow analogs have been used by many investigators in the past to evaluate analytical solution to drainage problems (Bear, 1972). The objectives of this study are: 1. Design and construct a viscous-flow analog for laboratory and classroom use, 2. Test the reliability of existing bi-level drainage theory with the analog, and 3. Provide design data for use in the solution of bi-level drainage problems. The bi-level drainage theory will be graphically presented for design purposes provided the theory is shown to …

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A Survey Of The Insect Fauna Of Canada Thistle, Cirsium Arvense, In South Dakota; And Studies Relating To Biological Control By Ceutorhynchus Litura And Cassida Rubiginose, Lance Jerome Nearman Jan 1973

A Survey Of The Insect Fauna Of Canada Thistle, Cirsium Arvense, In South Dakota; And Studies Relating To Biological Control By Ceutorhynchus Litura And Cassida Rubiginose, Lance Jerome Nearman

Electronic Theses and Dissertations

A total of 121 indigenous insect taxa representing 9 orders, 64 families, 103 genera and 118 species was collected from Canada thistle (Compositae: Cirsium arvense (L.) Scop.) in South Dakota during 1970 through 1973. This survey identified the major phytophagous and entomophagous insect fauna associated with this noxious weed. The common phytophagous species observed feeding on thistle were all polyphagous and failed to control Canada thistle below the economic level. Field cage releases of adult Ceutorhynchus litura (F.) weevils were made on a thistle infested pasture site located in east central South Dakota during 1972-1973. Ninety-nine weevils were released in …

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Processing Methods For Corn Grain Fed With Various Types, Sources And Levels Of Roughage To Cattle, Jerry Burkhardt Jan 1973

Processing Methods For Corn Grain Fed With Various Types, Sources And Levels Of Roughage To Cattle, Jerry Burkhardt

Electronic Theses and Dissertations

The research reported in this thesis involved experiments to determine the value of grain processed by various methods when fed various kinds and ratios of concentrate to roughage to feedlot beef animals of various ages and degree of fatness.

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