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Full-Text Articles in Life Sciences

Evaluation Of Early Maturing Cultivars, Optimal Harvest Timing, And Canopy Reflectance Of Peanut To Maximize Grade And Yield, Joseph Bryan Whittenton May 2023

Evaluation Of Early Maturing Cultivars, Optimal Harvest Timing, And Canopy Reflectance Of Peanut To Maximize Grade And Yield, Joseph Bryan Whittenton

Theses and Dissertations

Peanut digging timing is difficult to predict due to indeterminate growth and peanut pods maturing underground, resulting in the need to research methods that provide consistent measurements, while reducing time and effort for farmers and researchers. Experiments were conducted to evaluate the accuracy of the Maturity Index 1 and Maturity Index 2 in predicting peanut grade, the accuracy of the North Carolina 2 degree day method in predicting peanut yield, and remote sensing vegetative indices sensitivity equivalence (SEq) to peanut Maturity Index 2 and harvest grade (TSMK) for cultivars IPG-914 and Georgia-06G in Mississippi.

Maturity Index 1 and …


Comparison Of Botanical Composition Methods And Change Over Time In Kentucky Pastures, Echo Elizabeth Gotsick Jan 2023

Comparison Of Botanical Composition Methods And Change Over Time In Kentucky Pastures, Echo Elizabeth Gotsick

Theses and Dissertations--Plant and Soil Sciences

Botanical composition of pastures has been measured with numerous methods over the last century, but there have been limited direct comparisons between methods. The objective of this study was to compare botanical composition methods, to determine the most accurate and efficient method, and to access pasture composition change over time. Six farms with two pastures each were monitored across the state of Kentucky. Sampling occurred fall 2020 through fall 2022, three times a year using the following methods: step point, visual estimation, occupancy grid, and point quadrat (used as a reference method). The occupancy grid showed the highest similarity to …


Determining The Effects Of Plant Extracts And Saltro Nematicide On Hatching, Mortality And Reproduction Of The Soybean Cyst Nematode (Heterodera Glycines), Bishnu Prasad Dhital Jan 2020

Determining The Effects Of Plant Extracts And Saltro Nematicide On Hatching, Mortality And Reproduction Of The Soybean Cyst Nematode (Heterodera Glycines), Bishnu Prasad Dhital

Electronic Theses and Dissertations

Soybean cyst nematode (SCN) is a microscopic worm that infects and feeds from the soybean roots, hence robbing the plant of nutrients, and entry wounds may facilitate other pathogens to infect the roots. Current SCN management practices include cultural, chemical, and biological methods. Cultural practices such as, crop rotation with non-host and different tillage practices are not efficient due to the persistent nature of SCN in the soil. Chemical nematicides, though effective, can be expensive, and some are not environmentally sound. SCN resistant soybean varieties are mainly derived from one source, PI 88788 and SCN population have already evolved to …


Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason Dec 2019

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …


Agronomic And Quality Response Of Hard Red Spring Wheat Genotypes To Management Systems In South Dakota, Jonathan Kleinjan Jan 2019

Agronomic And Quality Response Of Hard Red Spring Wheat Genotypes To Management Systems In South Dakota, Jonathan Kleinjan

Electronic Theses and Dissertations

Intensive cereals management techniques such as multiple fungicide applications and in-season split N applications have been used to successfully improve wheat yields in Europe and in some winter wheat production areas of the USA. However, research on the effects of these management practices and their interaction with genotypes is limited in the hard red spring wheat (HRSW) production areas of the USA. The objectives of this study were to: (i) compare management treatments and (ii) quantify any interaction effects between management and genotype on the agronomic characteristics and relevant flour and dough properties of locally-adapted HRSW genotypes. A randomized complete …


Factors Affecting The Regrowth Of Ilex Glabra In A Routinely Burned Longleaf Forest, Jaybus Price May 2018

Factors Affecting The Regrowth Of Ilex Glabra In A Routinely Burned Longleaf Forest, Jaybus Price

Master's Theses

This study examines the effects of historical management by use of prescribed fire on Ilex glabra stems/m2 and factors affecting the regrowth of I. glabra after a prescribed burn to gain beneficial knowledge for management purposes. Environmental factors and morphological parameters of I. glabra were sampled before and after a prescribed burn of the Longleaf Trace Nature Preserve in September 2016. The study site is located in Lamar County, Mississippi, just west of Hattiesburg, MS. Stem densities of I. glabra were collected once before the prescribed burn and twice after the prescribed burn at 2 month and 9 month …


Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind Jan 2018

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence …


Irrigated Zea Mays Response To Nitrogen And High Plant Population Density In Narrow Rows, Julie Baniszewski Jan 2016

Irrigated Zea Mays Response To Nitrogen And High Plant Population Density In Narrow Rows, Julie Baniszewski

Theses and Dissertations--Plant and Soil Sciences

Modern genetics have improved maize hybrids to better tolerate stress, use nutrients more efficiently and potentially yield higher. Management practices, such as narrow row technology and high plant population density (PPD) may further improve yields in modern maize under irrigated, non-limiting conditions. High PPD (74, 99, 124, 148 K seeds ha-1) were tested in narrow rows with up to four nitrogen (N) rates in three locations over two years in Kentucky with a modern maize hybrid in irrigated, non-limiting conditions. Results indicate that optimal seeding rates were 99,000 to 124,000 seeds ha-1, providing maximum yield and …


A Comparison Of Management Strategies For The Federally Endangered Running Buffalo Clover (Trifolium Stoloniferum) On The Blue Grass Army Depot, Ky, Alexi David Dart-Padover Jan 2015

A Comparison Of Management Strategies For The Federally Endangered Running Buffalo Clover (Trifolium Stoloniferum) On The Blue Grass Army Depot, Ky, Alexi David Dart-Padover

Online Theses and Dissertations

Running buffalo clover (Trifolium stoloniferum) is a federally endangered plant that appears to depend on habitat disturbance, although proposed management strategies such as cattle grazing, mowing, and herbicide application have never been compared in a controlled study. We evaluate the efficacy of these techniques on the Blue Grass Army Depot (BGAD) in Madison County, KY, where one of T. stoloniferum’s largest populations occurs. Fifty-nine patches of T. stoloniferum on the BGAD were treated annually between 2012 and 2014 with combinations of mowing and grass-specific herbicide. Patches of T. stoloniferum also were exposed to one of three types of cattle exposure …


Restoring The Longleaf Pine (Pinus Palustris) Forests Using Pineywoods Cattle Grazing In Conjunction With Prescribed Burning, L. Tyler Albin May 2014

Restoring The Longleaf Pine (Pinus Palustris) Forests Using Pineywoods Cattle Grazing In Conjunction With Prescribed Burning, L. Tyler Albin

Honors Theses

The longleaf pine (Pinus palustris) is major forest constituent of the Southern Coastal Plains of the United States. Ecologically, a virgin longleaf pine forests supports increased species richness. Since the 1800s, longleaf pine forests have been exploited as a massive source of commercial products (e.g., lumber, pulp, and naval stores). A decrease in species richness has been recorded following this vast decrease in longleaf pine presence. Rebuilding the longleaf pine ecosystem is essential for restoring species richness and maintaining the ecological health of many Costal Plains habitats. Presently, the most popular restoration and management method utilized is prescribed burning. Prescribed …


Managing Fusarium Wilt In Watermelon Production, Zachary Snipes Dec 2013

Managing Fusarium Wilt In Watermelon Production, Zachary Snipes

All Theses

Fusarium wilt of watermelon, caused by Fusarium oxysporum f. sp. niveum , was first described in 1894 in South Carolina and Georgia and has become a limiting factor in watermelon production worldwide. In recent years, restriction on use of the soil fumigant methyl bromide and the recent development of more virulent races of Fusarium oxysporum f. sp. niveum has created a critical need for alternative management techniques. In 2011-2013 field experiments were designed to evaluate the efficacy of incorporating a cover crop of hairy vetch into the soil to manage Fusarium wilt. Colony-forming units (CFU) of Fusarium oxysporum were sampled …


Integrated Management Of Downy Brome (Bromus Tectorum L.) Infested Rangeland, Heather Elwood May 2013

Integrated Management Of Downy Brome (Bromus Tectorum L.) Infested Rangeland, Heather Elwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Invasive weed species are a threat to the health and functionality of many rangeland systems. Downy brome (Bromus tectorum) is an invasive annual grass that affects the productivity of rangelands by decreasing the grazing capacity for livestock as well as altering the wildfire cycle and competing against more desirable vegetation for limited resources.

In 2006, an Invasive Plant Management Plan and Environmental Assessment was approved for Dinosaur National Monument, calling for prioritization of invasive species management on high value wildlife habitat, vector areas, and for species with a high ecological impact. The Cub Creek Watershed was identified as a priority …


Landscape Design, Cost Estimate, And Management Plan, Garrett Talbot Williams Dec 2012

Landscape Design, Cost Estimate, And Management Plan, Garrett Talbot Williams

Horticulture and Crop Science

The purpose of this project is to evolve a bleak landscape into something that the home owner can appreciate and love. This project will demonstrate the knowledge of this process to provide as a guide for others. This project gives an overview of all aspects of a landscape project including: drawings of an irrigation layout, planting plan, drainage plan, and a construction plan. This project takes place in Riverbank, California, which is located in the Central Valley. The property’s main centerpiece is a pool and adjacent waterfall. However, the landscape currently surrounding the pool is very bare and lacks aesthetic …


Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch May 2011

Process-Based Management Of Downy Brome In Salt Desert Shrublands: Assessing Pre- And Post- Rehabilitation Soil And Vegetation Attributes, Merilynn Carol Hirsch

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As an ecosystem driver, downy brome (Bromus tectorum L.) presents obstacles to land rehabilitation efforts, including restoring desirable species cover. Because damaged ecosystems may have crossed both abiotic and biotic thresholds, ecologically-based control strategies may assist with altering successional trajectories and restoring desirable plant species. My thesis research had three objectives: 1) assess soil and vegetation relationships in degraded salt desert ecosystems prior to implementing downy brome control treatments, 2) determine the effects of control treatments on soil properties and resident plant species, and 3) evaluate the relative importance of shrubland soil type, herbicide type, and herbicide rate on seedling …


Management Of Microbial Nitrate Production In Agricultural Soils, Wei Shi May 1998

Management Of Microbial Nitrate Production In Agricultural Soils, Wei Shi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrate (NO3-) is of central importance in the internal soil nitrogen (N) cycle. While animal wastes and nitrification inhibitors have been used in modern agriculture for decades, their effects on soil NO3- concentrations in relation to microbial NO3- production have not been well characterized. The objective of this research was to determine microbial NO3- production in relation to ammonium (NH4+) availability and nitrifier population activity in agricultural soils receiving animal wastes or nitrification inhibitors.

Several laboratory and field studies assessed the impacts of variously treated dairy wastes and …


Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk May 1981

Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two experiments were conducted in the semi-arid (400 millimeter annual rainfall) Macquarie region of New South Wales, Australia, at the Trangie Agricultural Research Station (31° 59'S; 147° S7'E), to examine (a) the way botanical parameters can be used to separate grazing and climatic impacts on range vegetation, and (b) how this delineation affects application of range science tenets (site, condition and trend) to different pasture types.

Two range sites were studied: Site 1, a light soil type, was dominated by annual grasses, legumes and forbs, whereas perennial grasses (mainly Chloris acieularis and Chloris truncata) dominated the heavy soils of …