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An Ecological Study Of The Vegetation Of The Grand River/Cedar River, Sioux, And Ashland Districts Of The Custer National Forest, Paul Luther Hansen Jan 1985

An Ecological Study Of The Vegetation Of The Grand River/Cedar River, Sioux, And Ashland Districts Of The Custer National Forest, Paul Luther Hansen

Electronic Theses and Dissertations

A land-classification system based on potential natural vegetation is presented for the Grand River/Cedar River, Sioux, and Ashland Districts of the Custer National Forest. The districts are located in northwestern South Dakota, southwestern North Dakota, and southeastern Montana. The vegetation was characterized according to habitat type based on concepts and methods developed by Daubenmire. A total of 169 stands were intensively sampled over a four-year period. Twenty-six habitat types were described including eight steppe, nine shrub-steppe, four woodland, and five forested habitat types. In addition, two shrub-steppe community types were identified. A diagnostic key is provided for field identification of …


Effects And Interactions Of Nitrogen And Soil Moisture Status Under A High Yield Irrigated Corn Environment, Dwayne L. Beck Jan 1983

Effects And Interactions Of Nitrogen And Soil Moisture Status Under A High Yield Irrigated Corn Environment, Dwayne L. Beck

Electronic Theses and Dissertations

A two-part study was conducted during the 1979 and 1980 growing seasons on irrigated lands adjoining the Missouri River in central South Dakota. Empirical [sic] models were developed to describe the response of irrigated corn (Zea mays L.) to soil water status and nitrogen fertilization at a location recently developed for sprinkler irrigation. Nitrogen fertilizer rates of 0, 100, 200, and 400 kg of N/ha were used under water treatments consisting of a 2.5 cm irrigation when soil water matric potential at a depth of 40 cm decreased to -35, -50, and -75 kPa. Yield differences due to soil water …


Soil Microfungal Relationships Associated With Grassland Reestablishment, Dennis C. Clarke Jan 1980

Soil Microfungal Relationships Associated With Grassland Reestablishment, Dennis C. Clarke

Electronic Theses and Dissertations

The mixed prairie association has a characteristic soil microfungal flora associated with the cover vegetation (Clarke and Christensen, 1980). Rhizosphere organisms are correlated with the cover vegetation (Christensen, 1969) and a change in the cover vegetation should be accompanied by a change in the organisms in the rhizosphere. Some disturbances that may lead to change in the cover vegetation are tillage, grazing, interseeding, mowing and fires. Christensen's (1980) review of species diversity and dominance in fungal communities indicates that in general these disturbances tend to reduce soil microfungal diversity while increasing the frequency of the remaining species. Other studies have …


Methods Of Analysis Of Yield From Antecedent Winter Water, Charles Gregg Carlson Jan 1978

Methods Of Analysis Of Yield From Antecedent Winter Water, Charles Gregg Carlson

Electronic Theses and Dissertations

This investigation is an evaluation of methods of analysis of water conserved during off-season periods and evaluation of the effect on the subsequent crop. Energy and water shortages during the midsummer peak irrigation season have forced farmers to consider the possibility of irrigation at times other than peak growth stages as an alternative practice. Dryland farmers are interested in the benefit of water conserving cultural practices such as summer fallow and snow trapping. To evaluate the benefit of these off-season practices, a yield function based upon water availability is necessary. In order to better understand the effects of off-season irrigation …


Water And Nitrogen Husbandry For Irrigated Corn In Central South Dakota, Stanley Eugene Papendick Jan 1978

Water And Nitrogen Husbandry For Irrigated Corn In Central South Dakota, Stanley Eugene Papendick

Electronic Theses and Dissertations

The purpose of this study was to evaluate the effects of supplemental water and nitrogen on corn yields. Central South Dakota was chosen as the location for this study because of its existing irrigation and the limited research data available from that part of the state. The objectives were: (1) to determine corn yield response to various water regimes, (2) to determine corn yield response to nitrogen applications, and (3) to determine corn yield response to nitrogen application methods.


Plant Availability Of Aqueous Phosphates Removed By Fly Ash, Paul D. Weeldreyer Jan 1978

Plant Availability Of Aqueous Phosphates Removed By Fly Ash, Paul D. Weeldreyer

Electronic Theses and Dissertations

Recycling non-renewable resources has become increasingly. important as man has continuously expected more and more from his environment. As stated by Spendlove (1976): "Recycling certainly is not new. It appears, in fact, to be one of the most obvious laws of nature, much like the seasons, the tides, and the life and death processes. It is not surprising, therefore, that the greatest motivating force behind present recycling efforts is the worldwide concern for the deteriorating natural environment." This ever-increasing demand for more production has created the need for more stringent pollution controls to maintain an acceptable quality of life. Pollution …


The Effect Of Foliar Fertilization On Soybean Yield And Leaf Necrosis, Robert Jay Goos Jan 1978

The Effect Of Foliar Fertilization On Soybean Yield And Leaf Necrosis, Robert Jay Goos

Electronic Theses and Dissertations

The soybean (Glycine max (L.) Merrill) is a very important world crop. The seed is rich in both protein and oil, making it a valuable human food resource. Many scientists believe that there are physiological barriers preventing increased soybean yields. Any agronomic discovery that would consistently increase soybean yields would be important to world food production. One possible yield barrier in soybeans concerns the mineral nutrition of the plant during the seed-filling stages of growth. During this period of growth, translocation of N, P, K, and S from the plant foliage to the developing seed occurs, accompanied by a virtual …


The Transfer Of Resistance To Wheat Streak Mosaic Virus (Wsmv) From Wheatgrass (Agropyron Intermedium (Host.) Beauv.) To Common Wheat (Triticum Aestivum L. Em. Thell.) By Irradiation, Harnek S. Sandhu Jan 1978

The Transfer Of Resistance To Wheat Streak Mosaic Virus (Wsmv) From Wheatgrass (Agropyron Intermedium (Host.) Beauv.) To Common Wheat (Triticum Aestivum L. Em. Thell.) By Irradiation, Harnek S. Sandhu

Electronic Theses and Dissertations

A virus disease, wheat streak mosaic, has been an important, unsolved problem of winter wheat which is a major crop in South Dakota. F1BC3 monosomic alien addition seeds having three doses of Centurk were irradiated with fast neutrons to translocate a segment of the alien chromosome accounting for immunity from wheat streak mosaic virus to a Centurk chromosome. Immune plants from the irradiated seeds were used as male parents onto Centurk and about 2,000 F1BC4 seeds obtained. Cytological examination of pollen mother cells of 151 resistant F1BC4 plants indicated that the …


Purine-Thiamine Anabolism During Cellular Morphogenesis In Myxococcus Xanthus, Wen-Cherng Tsai Jan 1976

Purine-Thiamine Anabolism During Cellular Morphogenesis In Myxococcus Xanthus, Wen-Cherng Tsai

Electronic Theses and Dissertations

Purine-thiamine anabolism during cellular morphogenesis in Myxococcus xanthus was investigated. One of the approaches was to test vegetative and myxospore (2.5 h and 8 h) extracts of M. xanthus CW-2 for their ability to synthesize the second de novo intermediate, 5'-phosphoribosylglycinamide, from beginning precursors either by way of phosphoribosyl-pyrophosphate amidotransferase (EC 2.4.2.14) or ribose-5-phosphate aminotransferase. Results indicate the presence of both the amido- and aminotransferases in both types of extracts, and both enzymes appear to be present at about the same level (per milligram of protein) in vegetative cells, myxospores (2.5 h and 8 h), and in a bacterial prototype, …


A Comparative Study Of Ribonuclease From Two Winter Barley Cultivars Based Upon Separation, Purification And Partial Characterization Of Rna-Degrading Enzymes, Raymond Sze-Chung Wong Jan 1975

A Comparative Study Of Ribonuclease From Two Winter Barley Cultivars Based Upon Separation, Purification And Partial Characterization Of Rna-Degrading Enzymes, Raymond Sze-Chung Wong

Electronic Theses and Dissertations

The differences in the response to KCl of the RNA-degrading enzymes of two barley cultivars, “Dicktoo” (a hardy type) and "Tennessee Winter” (a non-hardy type), were investigated. Two types of enzymes, ribonuclease (RNase) and nuclease, were separated from crude extracts by disc electrophoresis. The electrophoretic gels were assayed for RNA-degrading activity in the presence and absence of EDTA (EDTA is a nuclease inhibitor). By means of density gradient isoelectric focusing, the nuclease preparation from Tennessee Winter was shown to have an isoelectric point between 5.3 and 5.5, while the nuclease preparation from Dicktoo has three isoelectric points of 4.9, 5.5 …


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 …


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 …


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 …


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. …


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 …


Physiological Regulation Of Cyclic Flowering In Flax, Aurora Salazar Hovland Jan 1972

Physiological Regulation Of Cyclic Flowering In Flax, Aurora Salazar Hovland

Electronic Theses and Dissertations

The flowering pattern of flax (Linum usitatissimum, L.) is cyclic in nature with periods of blossoming separated by periods of rest. To study the regulation of flowering cycles, four experiments were conducted. The first two dealt with nutritional aspects of cyclic flowering by imposing environmental stresses which conceivably might regulate flowering pattern nutritionally. The third and fourth experiments dealt with regulation from hormonal systems and included in vitro regulation of bud growth by growth regulators as well as characterization of endogenous hormonal systems by fluorimetry and bioassays. In the first experiment, the effects of light intensity, temperature, nitrogen and defoliation …


Estimation Of N Availability And No3-N Movement In Soils, Raymond Charles Ward Jan 1972

Estimation Of N Availability And No3-N Movement In Soils, Raymond Charles Ward

Electronic Theses and Dissertations

Objectives of this study were: (a) to evaluate several N soil tests that are used to estimate soil N availability, and (b) to measure the distribution of inorganic N in the soil profile after an application of fertilizer N. Small grain yield response from an application of 17, 34, or 67 kg N/ha was used as the parameter of N availability. These parameters were related to 23 independent variables by use of a step wise multiple regression program. Nitrogen soil tests and climatic factors (rainfall and temperature) were the independent variables involved in the analysis. Nitrogen soil tests included were …


Recognizability And Reproducibility Of Airphoto Interpreted Landscape Units, Robert Dean Heil Jan 1972

Recognizability And Reproducibility Of Airphoto Interpreted Landscape Units, Robert Dean Heil

Electronic Theses and Dissertations

A physiographic terrain analysis study using the principles of airphoto interpretation was made: (1) to determine the internal homogeneity of airphoto interpreted mapping units, (2) to determine the variability in characteristics among different occurrences of the same mapping unit, and (3) to determine if the units differentiated were sufficiently different to warrant discrimination. The study was conducted in Sedgewick County, Colorado. The study area was comprised of four distinctly different land forms [sic]: a major river and its associated floodplain and terraces; a level to nearly level loamy upland plain; a level to sloping sandy upland plain; and steeply sloping, …


Evidence For The Presence Of Two Nucleases In Barley Tissue And The Influence Of Genotype On Their Properties, Clay G. Johnson Jan 1972

Evidence For The Presence Of Two Nucleases In Barley Tissue And The Influence Of Genotype On Their Properties, Clay G. Johnson

Electronic Theses and Dissertations

Several lines of evidence have shown that genetic variability exists within the barley species (Hordeum vulgare L.) with respect to the kinetics and specificity of yeast ribonucleic acid degradation. Initial efforts demonstrated that ribonuclease (RNase), in the crude soluble protein fraction from the cultivar Dicktoo, was inhibited by KC1 and phosphate. RNase activity was enhanced if heated to 60 C for short periods. In contrast, RNase in the crude soluble protein of the cultivar Tennessee Winter showed no altered response by either KC1 or phosphate. Maximal RNase activity was at pH 5.0 for extracts of both cultivars (0.16 M KC1), …


Herbicide Residue And Weed Control In Switchgrass, Charles Nicholas Smith Jr. Jan 1971

Herbicide Residue And Weed Control In Switchgrass, Charles Nicholas Smith Jr.

Electronic Theses and Dissertations

Purposes of this study were to find an effective herbicide for control of grassy weeds in a pasture, to adapt known laboratory procedures for analyzing residues and to determine amounts of residues during the growing season in treated plots. Nine herbicides were screened for controlling grassy weeds, primarily downy brome (Bromus tectorum L.) in a native pasture. Data indicated 2-chloro-4-ethylamino-6-isopropylamino-s-triazine (atrazine) applied postemergence at 1 lb/A was the most effective at 85% control. The following year, atrazine, 2-chloro-4, 6-bis­ (ethylamino)-s-triazine (simazine) and 2, 2-dichloropropionic acid (dalapon) each at 1, 2 and 3 lb/A were applied preemergence to switchgrass pasture. Of …


The Yielding Ability Of Bulked F2 Barley Crosses And Parents In Comparative Yield Trials, Walter Lowell Nelson Jan 1948

The Yielding Ability Of Bulked F2 Barley Crosses And Parents In Comparative Yield Trials, Walter Lowell Nelson

Electronic Theses and Dissertations

Present methods of breeding new barley varieties are costly, laborious and lengthy. Populations from a cross are grown until they become homozygous before much selection by comparative yield trails can be made. The pedigree method limits the number of crosses that can be studied because of the large segregating populations necessary for the expression of desired gene combinations. Because of the enormous amount of work involved, it would be highly desirable for a plant breeder to work only with superior parental material. The capabilities of a plant breeder would be greatly increased by an method which would allow him to …


The Effect Of Cultivation On Certain Chemical And Physical Properties Of Some South Dakota Soils, Oscar E. Olson Jan 1937

The Effect Of Cultivation On Certain Chemical And Physical Properties Of Some South Dakota Soils, Oscar E. Olson

Electronic Theses and Dissertations

Soil Nutrient losses have followed closely in the paths of advancing frontiers in agriculture. Remedies for depletion as the result of overcropping were sought by George Washington, whose interest and investigation of soil nutrient losses probably represent the earliest attention given to land exploitation in the United States, which at the present time has become a problem of national concern. Soil losses have been attributed to a number of causes , among which are cropping, erosion, leaching, burning, and rapid oxidation of organic matter in the soil. Associated with soil nutrient losses, certain significant physical and chemical changes may occur …


The Effect Of A Varying Moisture Supply At Different Periods Of Growth On The Development, Yield And Quality Of Flax, William K. Soule Jan 1931

The Effect Of A Varying Moisture Supply At Different Periods Of Growth On The Development, Yield And Quality Of Flax, William K. Soule

Electronic Theses and Dissertations

In the flaxseed producing section of the United States consisting of the states of North Dakota, South Dakota, and Minnesota and Montana, periods of drought frequently occur during some part of the growing season. The time of occurrence varies from early spring to fall. Such periods have a profound effect on the normal growth of the plant.


A Study Of Certain Physical And Chemical Characteristics Of Flaxseed And Of Linseed Oil, With Especial Reference To Date Of Harvest, Leo F. Puhr Jan 1927

A Study Of Certain Physical And Chemical Characteristics Of Flaxseed And Of Linseed Oil, With Especial Reference To Date Of Harvest, Leo F. Puhr

Electronic Theses and Dissertations

From the review of the foregoing literature on flax, it is evident that little work has ever been done on the chemical composition of flax. Most of the work on flax up to the present time has been confined to the diseases of flax, principally the securing of varieties that are resistant to wilt. In an attempt to secure information in regard to the factors affecting the physical characteristics and chemical composition of flaxseed the following work has been done in this experiment: 1. The effect of time of harvesting upon physical characteristics of the seed. 2. The relation of …


A Study Of The Forage Plants Of South Dakota With Their Fungous And Insect Enemies, David Griffiths Jan 1893

A Study Of The Forage Plants Of South Dakota With Their Fungous And Insect Enemies, David Griffiths

Electronic Theses and Dissertations

The main object of this study being a better acquaintance with fungous parasites, the work on the host plants has been considerably abridged in order that the discussion might be shortened. It was the plan at first to include in this paper a carefully written description of each of the principal forage plants of the state. The futility of such a plan, however, soon became apparent, and it was accordingly decided to omit the description and include simply Distribution,

Habitat, Value as Forage, and the Fungous Parasites of each host. There are, therefore, several of our best forage plants omitted …