Digital Commons Network^™

Applied Species Delimitation In Microbial Taxa And Plants, Austin C. Koontz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species are a fundamental concept in biology, and many subdisciplines in biology utilize species in aspects of theory and in the communication of results. Given the centrality of species in biological science, it can seem surprising that there is no universal definition amongst biologists of what, strictly speaking, a species is. In fact, there are, by some estimates, over 20 different "species concepts", and this lack of a consensus is termed "the species problem". This problem has theoretical underpinnings, but has become more relevant as advances in sequencing technologies over the past two decades have allowed researchers to probe the …

Information Sources, Willingness To Volunteer, And Attitudes Towards Invasive Plants In The Southwestern United States, Leith Seeley Tidwell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis examines results of a survey conducted in the Southwestern United States focusing on attitudes towards invasive plants, public preferences for information sources and willingness to volunteer in invasive plant management. This research demonstrates that the public is interested in the problem and control of invasive plants. In a broad context there is agreement among respondents that invasive plants pose a threat to the environment and control efforts, including the use of herbicides, should be allowed to occur. Given the differences between general and specific attitudes towards invasive plants, it is suggested education and awareness programs be designed to …

Utilization Of Spatially Distributed Soil Resources By Several Species Common To The Great Basin, Sarah Duke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Heterogeneous spatial and temporal distributions of soil resources important to plant growth have been documented in the sagebrush steppe ecosystem. There can exist as much variability in soil resources within the root zone of individual plants as exists across an entire field. The objective of this dissertation research was to evaluate how plants respond to, utilize and influence the spatial heterogeneity of soil resources. The three specific sets of questions addressed are outlined in the three main chapters of this dissertation.

My first study addressed how the number and concentration of phosphorus (P) patches in the root zone of an …

Carbon Dioxide Toxicity In Wheat, Robert Spanarkel

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research was conducted to quantify short- and long-term effects of atmospheric carbon dioxide on wheat. Growth, development, and yield of the spring wheat cultivar Veery-10 were measured in response to CO₂ concentrations of 340 (ambient), 1200, and 2500 μmol moI^-1 of CO₂ air. These 3 CO₂ levels were chosen to provide a control group, a predicted optimal CO₂ environment, and a potentially toxic CO₂environment, respectively. A recirculating hydroponic system provided a near-optimal root-zone environment that was identical for all CO₂ treatment levels. Environmental factors, other than CO₂, were …

Utilization Of Crested Wheatgrass Plants By Cattle Under Several Grazing Regimes, Patricia Selann Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Patterns of grazing on individual crested wheatgrass plants were studied using scale maps of plant basal outlines within randomly located plots. The occurrence and extent (part of plant grazed, stubble height) of grazing on each plant was recorded on the maps at two and three day intervals throughout a grazing treatment. Allometric equations for estimating phytomass from plant photosynthetic volume were generated using nonlinear regression analysis. Equations were specific to year. The percent weight remaining in the stubble of a grazed plant was estimated using a second-order polynomial equation relating cumulative percent plant height to cumulative percent plant weight. A …

Belowground Resource Exploitation In Semiarid Plants: A Comparative Study Using Two Tussock Grasses That Differ In Competitive Ability, David M. Eissenstat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relative competitive abilities of Agropyron desertorum and Agropyron spicatum were compared using Artemisia tridentata transplants as indicator plants. Although these two tussock grasses have similar shoot growth forms and shoot physiological characteristics, they have substantial differences in their competitive abilities. Artemisia had lower survival, growth, reproduction, and water potential when transplanted into neighborhoods of A. desertorum than in neighborhoods of A. spicatum.

Plant attributes associated with the differences in competitive ability were explored. Agropyron desertorum and A. spicatum have remarkably similar potential growth rates at warm soil temperatures. In a prolonged cold soil temperature treatment in the greenhouse, …

A Survey Of Plants And Animals Of Hill And Wendover Bombing Ranges, Western Utah, Mary Sue Fisher

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The United States Air Force was required by the Sikes Act (16 USC 670 et seq.) to operate Hill and Wendover Bombing Ranges under a Land and Wildlife Management Plan consistent with military objectives. A preliminary biological inventory was conducted to provide basic information necessary for preparation of an appropriate management plan. The inventory was conducted over a one year period utilizing 60 field days on the ground and 30 hours of flying time. A list of vertebrates present on the bombing ranges was formed by general observation of large mammals, birds and reptiles, and trapping of small mammals. …

The Effect Of Four Mine Spoil Treatments On The Seedling Water Relations Of Two Plant Species, Lorraine K. Van Kekerix

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface mines in mountainous areas cause environmental deterioration at lower elevations in the watershed. The most successful long term solution to the downstream problem is revegetation. However, mine spoils are low in essential plant nutrients, have low water holding capacity, and are often acidic. These factors limit plant colonization. Plants must also be adapted to the environmental conditions of high elevations.

At the McLaren Mine, }1ontana, at 2800 m, it was observed that seedlings on revegetation plots were desiccated, indicating possible water deficits. Field and growth chamber studies were carried out to determine the effects of some spoil ameliorating treatments …

Feeding Behavior Of Pen Reared Mule Deer Under Winter Range Conditions, Michael A. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the feeding responses of mule deer to a system of spring livestock grazing. The specific purposes were 1) to determine botanical composition of diets selected by mule deer on a winter range subjected to previous spring grazing by sheep compared to one with no sheep grazing and 2) to develop a basis for predicting selection of individual plants by deer, based on physical characteristics of the plants and the species and physical proximity of associated plants.

The study was conducted within the framework of a completely randomized experimental design with two treatments. Variables controlled for each unit …

The Anatomical And Morphological Effects Of Dcpa On Seedlings Of Selected Species Of Plants, Bijan Shaybany

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Seeds of oat, green foxtail, squash and tomato were germinated in soil treated with different levels of DCPA (dimethyl 2, 3, 5, 6-tetrachlorote-rephthalate). The concentrations used varied according to the sensitivity of the plants to the chemical.

The response of oat and foxtail to DCPA was similar. The growth of booth root and shoot was reduced. This reduction was directly related to the concentration of DCPA. Anatomical studies showed that cells in the shoot and root meristems of treated plants were completely disarranged and that some of the cells of these regions were hypertrophied. Some clumping of nuclei was observed …

The Effect Of High Air Temperature And Depth Of Planting On The Emergence And Development Of Selected Grain Sorghum (Sorghum Vulgare) Cultivars, Jhander Orihuela

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The behavior of seedlings of six sorghum cultivars planted at 2.5, 5.0, 7.5, and 10.0 centimeters was studied in growth chambers at air temperatures of 28, 32, 36, and 40 centigrades (daytime).

A day length of 12 hours and a nighttime air temperature 8 centigrades lower than daytime were used throughout.

The cultivars, three hybrids and three varieties, were grown in sand culture. Field moisture capacity was maintained during the period of observation.

After 14 days of growth, data were collected on the emergence percentages, above ground growth, above ground oven dry weights, below ground growth, and below ground oven …

The Effect Of Decomposing Organic Matter On Zinc Level In Soil And Plants, Kamilia Shoukry Mohamed Shoukry

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

That proportion of the total zinc (Zn) in the soil that is available to plants is variable, and little is known about the various forms of Zn or even the extent to which it occurs. Because of the complexity of the problem, most workers have approached the problem of availability of Zn to plants from the opposite point of view, that is, the forms in which the added or available Zn becomes unavailable.

The Effect Of Various Levels Of Bicarbonate, Phosphorus, And Ph On The Translocation Of Iron In Plants, Ronald Conrad Doney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Line-induced chlorosis is a nutritional disease affecting many fruit trees, berries, ornamental shrubs, and flowers in Utah and the western United States. In fact, this disease is of wide distribution on calcareous soils throughout the world. Lime-induced chlorosis has contributed to untold economic loss and has challenged the technical ingenuity of plant and soil scientists throughout the world. As yet the exact cause of chlorosis has not been determined; consequently, no permanent cures have been found.

The first symptoms of this disease are characterized by an interveinal yellowing of younger leaves, with the veins remaining green. In more severe cases …

The Emergence And Survival Of Certain Forage Plants When Seeded In A Saline Soil, Devere Richard Mcallister

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Salty soils are recognized as an ever increasing problem connected with irrigation agriculture. Millions have been spent by state, federal and private agencies on technical research in an attempt to solve this problem. Other millions have been spent on drainage projects, land leveling, field explorations and soil amendments attempting to alleviate the situation in the field.