Agriculture Commons^™

Content Preparation Of Pre-Service Agricultural Education Teachers And Its Influence On Their Content Knowledge, Amber Houck

University of Kentucky Master's Theses

Content knowledge preparation for teachers is a crucial component of the modal curriculum model for education. The purpose of this study was to determine if the amount and quality of coursework preparation of pre-service University of Kentucky agriculture teachers influences their content knowledge as defined by the Praxis II agriculture exam scores. This study concluded that there was variability in coursework preparation of pre-service agriculture teachers at the University of Kentucky. Praxis II exam scores of pre-service teachers indicated that most students are meeting an adequate content knowledge level based on the exam material. It can also be concluded that …

Colloid Mediated Transport Of Heavy Metals In Soils Following Reclamation With And Without Biosolid Application, Jarrod O. Miller

University of Kentucky Doctoral Dissertations

Soils disturbed by strip mining practices may have increased colloid loads moving to groundwater resources, also enhancing the transport of contaminants into our water resources. We hypothesize that contaminant transport within soils following mining is enhanced by colloid mobility. Two sites were chosen for this study, a 30-year old reclaimed strip mine in southwest Virginia and a recently mined area from eastern Kentucky. Intact reclaimed soil monoliths were retrieved from sandstone derived soils in southwestern Virginia. Reclaimed monoliths from eastern Kentucky were recreated in the lab. Intact undisturbed (native) soil monoliths representing the soils before mining were also sampled for …

Map-Based Cloning Of An Anthracnose Resistance Gene In Medicago Truncatula, Shengming Yang

University of Kentucky Doctoral Dissertations

Anthracnose, caused by the fungal pathogen Colletotrichum trifolii, is one of the most destructive diseases of alfalfa worldwide. Cloning and characterization of the host resistance (R) genes against the pathogen will improve our knowledge of molecular mechanisms underlying host resistance and facilitate the development of resistant alfalfa cultivars. However, the intractable genetic system of cultivated alfalfa, owing to its tetrasomic inheritance and outcrossing nature, limits the ability to carry out genetic analysis in alfalfa. Nonetheless, the model legume Medicago truncatula, a close relative of alfalfa, provides a surrogate for cloning the counterparts of many agronomically important genes in …

The Role Of Spiders In The Detrital Food Web Of An Eastern Deciduous Forest, Erin Elizabeth Hladilek

University of Kentucky Doctoral Dissertations

Historically, terrestrial food web research has focused on describing the structure of aboveground grazing webs, and determining how interactions among plants, herbivores and higher trophic levels influence primary productivity. Detrital food webs however, play a significant role in regulation of ecosystem dynamics through direct impacts on decomposition. Unraveling the complex nature of detrital food web structure is critical to developing a better understanding of ecosystem function. Therefore the primary objective of this research was to describe the structure of the leaf-litter food web in a temperate deciduous forest, with emphasis on interactions between a community of generalist predators, the forest-floor …

Precision Agriculture: Realizing Increased Profit And Reduced Risk Through Cost Map And Lightbar Adoption, Benjamin Michael Kayrouz

University of Kentucky Master's Theses

This thesis examines the use of two specific types of precision agriculture technologies: cost maps and lightbar. Cost maps visually depict spatial differences in production costs. The visual depictions of these costs are represented using ArcGIS in an attempt to aide farmers in further decision making. Results will show that cost maps have great possibilities in their addition to the set of tools that farmers use in decision making. This thesis will expand the understanding of lightbar from a partial budget study to a whole farm model incorporating competition across different enterprises for labor and capital. The results from the …

Inorganic And Organic Phosphorus Interactions With Hydroxy-Interlayered Soil Minerals, Paul D. Shumaker Ii

University of Kentucky Master's Theses

Phosphorus (P), a necessary plant and animal nutrient, can also lead to eutrophication of fresh waters when in excess. Appropriate P management is necessary to prevent fresh water pollution. Mineralogy of soil clays has been shown to affect P adsorption, desorption, and movement through soils. Specifically, hydroxy-interlayered minerals have been shown to adsorb and retain inorganic P in soil systems. This study was designed to determine the sorption and desorption characteristics of inorganic, organic, and mixed forms of P interacting with soil hydroxy-interlayered vermiculites (HIV) and smectites (HIS), and compare the findings to sorption and desorption processes of natural aluminum …

Quantifying Cellulase In High-Solids Environments, Alicia Renée Abadie

University of Kentucky Master's Theses

In recent years, fungal and bacterial cellulases have gained popularity for the conversion of lignocellulosic material to biofuels and biochemicals. This study investigated properties of fungal (Trichoderma. reesei) and bacterial (Clostridium thermocellum) cellulases. Enzymatic hydrolysis was carried out with T. reesei using nine enzyme concentration and substrate combinations. Initial rates and extents of hydrolysis were determined from the progress curve of each combination. Inhibition occurred at the higher enzyme concentrations and higher solids concentrations. Mechanisms to explain the observed inhibition are discussed. Samples of C. thermocellum purified free cellulase after 98% hydrolysis were assayed to determine …

Assessing The Demand For Weather Index Insurance In Shandong Province, China, Lisha Zhang

University of Kentucky Master's Theses

Shandong Province, renowned as China’s greatest agricultural province, is dominated by smallholders growing rain-fed crops and vulnerable to severe weather shocks that can increase poverty rates. Weather index insurance, an innovative agricultural risk management product, may be an effective mechanism to address vulnerability to catastrophic weather risk in rural regions of China, including Shandong. This project evaluated current household livelihood and risk management strategies and farmer interest in weather index insurance. Data from 174 participants were collected using a methodology that included focus groups, questionnaires, and personal interviews. Despite limited access to formal financial services, Shandong farmers generally employ informal, …

An Analysis Of Kentucky Equestrian Trail Riders: Determining Rider Behaviors And Valuing Site Amenities That Contribute To Repeat Visits, Katharine Auchter

University of Kentucky Master's Theses

The purpose of this travel cost study is to determine how rider behaviors and site characteristics influence repeat visits for equestrian trail riding in Kentucky. Primary data was collected via a survey developed and administered to trail riders in person and online. The average surveyed trail rider tends to be female, about 46 years old, with some higher education, and an annual household income of $65,000. She makes 11 trips to a specified site per year, 8 of which are daytrips, usually in the fall, and traveling 132 miles round trip. From other information gathered, an index of trail characteristics …

Agricultural Situation And Outlook Fall 2007, Chuck Corby, Kenneth H. Burdine

Agricultural Situation and Outlook

No abstract provided.

Corn Stover Availability And Collection Efficiency Using Typical Hay Equipment, Robert M. Prewitt, Michael D. Montross, Scott A. Shearer, Timothy S. Stombaugh, Stephen F. Higgins, Samuel G. Mcneill, Shahab Sokhansanj

Biosystems and Agricultural Engineering Faculty Publications

Corn stover has been identified as a potential feedstock for the production of fermentable sugars and thermochemical processes. The availability and efficiency of typical hay equipment for collecting corn stover has not been well quantified. Corn stover was collected for two years on a central Kentucky farm near Louisville. Six different harvesting treatments, using traditional hay equipment, were used to harvest corn stover. A rotary mower, rotary scythe (flail-type mower with windrow-forming shields), parallel bar rake, and a round baler were utilized. The average stover moisture content prior to grain harvest was above 40%, and field drying was required before …

Agricultural Lime Recommendations Based On Lime Quality, Greg Schwab, Lloyd W. Murdock, David C. Ditsch, Monroe Rasnake, Frank J. Sikora, Wilbur Frye

Agriculture and Natural Resources Publications

Soil acidity is one of the most important soil factors affecting crop growth and ultimately, yield and profitability. It is determined by measuring the soil pH, which is a measure of the amount of hydrogen ions in the soil solution. As soil acidity increases, the soil pH decreases. Soils tend to be naturally acidic in areas where rainfall is sufficient to cause substantial leaching of basic ions (such as calcium and magnesium), which are replaced by hydrogen ions. Most soils in Kentucky are naturally acidic because of our abundant rainfall. Some nitrogen fertilizers are also a source of soil acidity, …

The Kentucky Agricultural Economic Outlook For 2007, Linda Inman, Kenneth H. Burdine

Kentucky Agricultural Economic Outlook

No abstract provided.

Economic Analysis Of Cellulase Production Methods For Bio-Ethanol, Jun Zhuang, Mary A. Marchant, Sue E. Nokes, Herbert J. Strobel

Biosystems and Agricultural Engineering Faculty Publications

The cost of cellulase enzymes has limited the feasibility of producing ethanol from fibrous biomass. Traditional submerged fermentation (SmF) was compared to an alternative method of producing cellulase, solid state cultivation (SSC). Results from an economic analysis indicated that the unit costs for cellulase enzyme production were $15.67 (The prices are all 2004 prices in this article, except otherwise stated. We deflated newer prices to 2004 prices using a deflation factor 0.9 per year and inflated older prices to 2004 prices using an inflation factor 1.1.) per kilogram ($/kg) and $40.36/kg, for the SSC and SmF methods, respectively, while the …

Agricultural Situation And Outlook Fall 2006, James Mansfield, Timothy A. Woods

Agricultural Situation and Outlook

No abstract provided.

Development And Testing Of A Low-Cost Condensation Detection System, Michael D. Montross, George A. Duncan, Richard S. Gates

Biosystems and Agricultural Engineering Faculty Publications

A condensation sensing and control system was designed to detect condensation using a commercially available leaf wetness sensor (LWS). The leaf wetness sensor was a variable resistance grid-type that responded to moisture on the surface. A circuit was developed to compare the LWS voltage output to a user specified reference voltage, and operate a relay for possible switching of a humidity control device (for example a fan and/or heater). The condensation detection system operation was validated in an environmental chamber in the laboratory using a heat exchanger and water bath. Condensate was immediately detected when the plate was cooled below …

Vertical Loads Due To Wheat On Obstructions Located On The Floor Of A Model Bin, Marek Molenda, Michael D. Montross, Sidney A. Thompson, Jozef Horabik

Biosystems and Agricultural Engineering Faculty Publications

Tests were conducted in a model grain bin to evaluate the vertical loads acting on differently shaped obstructions embedded in wheat during filling, detention, and discharge. The bin had corrugated galvanized steel walls with a 1.83 m diameter and a flat bottom. All tests were conducted in a bin that was centrically loaded and unloaded. Three differently shaped obstructions (disc, cone, and cylinder) were tested; each had a circular base equivalent to 6% of the bin floor area. The obstructions were supported in the bin using a three-legged support structure. Each leg of the support structure rested on a load …

The Kentucky Agricultural Economic Outlook For 2006, Linda Inman, A. Lee Meyer, Gina Wilkie

Kentucky Agricultural Economic Outlook

No abstract provided.

Localization Of Diplodia Pinea In Diseased And Latently-Infected Pinus Nigra, Jennifer Lee Flowers

University of Kentucky Doctoral Dissertations

Diplodia pinea causes Diplodia tip blight on more than 30 different pine species. During the past 10 years, Diplodia tip blight has emerged as a serious problem in landscape and Christmas tree farms in this region. Surveys of diseased and symptomless Austrian pines revealed that latent infections of symptomless shoots by D. pinea were common. Latent infections may account for the recently observed rapid decline of mildly diseased pines in our region. To investigate the colonization habits of D. pinea within its host, molecular cytology was attempted and traditional histology was performed on naturally infected, diseased and asymptomatic Austrian pine …

Influences Of Host Size And Host Quality On Host Use In A Seed-Feeding Beetle, Angela Rocío Amarillo-Suárez

University of Kentucky Doctoral Dissertations

For insects that develop inside discrete hosts both host size and host quality constrain offspring growth, influencing the evolution of body size and life history traits. This dissertation examines the effects of host size, host quality, and intraspecific competition on life history and associated traits of populations of the seed-feeding beetle S. limbatus adapted to different host plants, and quantifies population differences in phenotypic plasticity. Populations of the study correspond to divergent clades of the species phylogeography (Colombia and United States).

Clades compared differ genetically for all traits when beetles were raised in a common garden. Contrary to expectations from …

Distribution Pattern Variability Of Granular Vrt Applicators, John P. Fulton, Scott A. Shearer, Stephen F. Higgins, Dennis Wayne Hancock, Timothy S. Stombaugh

Biosystems and Agricultural Engineering Faculty Publications

Granular applicators equipped with variable-rate technology (VRT) have gained popularity in recent years as a result of increased interest in variable-rate application. The purpose of this investigation was to characterize distribution patterns at varying rates for different granular applicators. Uniform-rate (UR) tests were conducted to assess the accuracy of variable-rate application from four granular applicators: two spinner-disc spreaders (A and B), and two pneumatic applicators (C and D). Pattern results indicated a consistent triangular pattern for spinner spreader B and consistent patterns for the pneumatic applicators (C and D). However, applicator D produced pattern variations at the center and right …

Rate Response Assessment From Various Granular Vrt Applicators, John P. Fulton, Scott A. Shearer, Stephen F. Higgins, Matthew J. Darr, Timothy S. Stombaugh

Biosystems and Agricultural Engineering Faculty Publications

Variable-rate technology (VRT) adds complexity to application equipment, thereby confounding the assessment of applicator performance. The intent of this investigation was to assess the rate response of various VRT granular applicators: two spinner spreaders (A and B), and two pneumatic applicators (C and D). Variable-rate (VR) tests were conducted to quantify the rate response characteristics (delay and transition times) for the applicators. A sigmoidal function was used to model the rate response for five of the six tests. Applicator A exhibited a linear response during decreasing rate changes. Results indicated that only applicator B demonstrated consistent delay and transition times, …

Agricultural Situation And Outlook Fall 2005, Matt Ernst, Kenneth H. Burdine

Agricultural Situation and Outlook

No abstract provided.

Spatial Variation Of Protein, Oil, And Starch In Corn, Samuel G. Mcneill, Michael D. Montross, Scott A. Shearer

Biosystems and Agricultural Engineering Faculty Publications

Significant spatial yield variations are known to exist in cornfields with different soil types, topsoil depth, and other variables. Similarly, variations might also be found among the highly valued chemical components (oil, protein, and starch) in corn kernels due to local differences in soil type, fertility, acidity/pH, organic matter, etc. This study quantified the spatial variability of protein, oil, and starch content of corn from two conventional cornfields and two high-oil cornfields. Whole ears were harvested by hand from 20 to 40 randomly selected locations within each field. A differential global positioning system (DGPS) receiver recorded the location of each …

Permeability Of Corn, Soybeans, And Soft Red And White Winter Wheat As Affected By Bulk Density, Michael D. Montross, Samuel G. Mcneill

Biosystems and Agricultural Engineering Faculty Publications

Darcy’s law is a function of viscosity, permeability, and velocity and can be used to predict the airflow resistance in granular materials at low air velocities. Permeability also governs the magnitude of natural convection currents during periods of non-aerated grain storage. The permeability of corn, soybeans, soft white winter wheat, and soft red winter wheat were measured as a function of bulk density and moisture content. Air was passed through a column of grain and the flow rate and pressure drop measured. Bulk density and kernel density were also measured to determine the porosity of grain in the test column. …

Airflow Resistance Of Seeds At Different Bulk Densities Using Ergun's Equation, Marek Molenda, Michael D. Montross, Samuel G. Mcneill, Jozef Horabik

Biosystems and Agricultural Engineering Faculty Publications

Airflow resistance of grains and oilseeds has been extensively studied. Traditionally the data has been presented using Shedd’s curves. However, this assumes that airflow resistance is independent of grain depth. Grain undergoes compaction during storage that changes the bulk density, porosity, and therefore the airflow resistance. Ergun’s equation is a function of particle size and porosity of the granular material. Airflow resistance by Ergun’s equation was used to predict the pressure drop across a column of corn, soft white winter wheat, soft red winter wheat, and soybeans at three moisture content levels and two bulk densities. The maximum root mean …

Crop Yield Response To Precision Deep Tillage, Larry G. Wells, Timothy S. Stombaugh, Scott A. Shearer

Biosystems and Agricultural Engineering Faculty Publications

Experimental precision deep tillage was applied at three sites in central Kentucky with relatively well-drained silt loam soils in no-till crop production. Fields were divided into 0.4 ha (1 ac) grid cells using DGPS mapping. Assessment of soil compaction by machinery traffic was made using multiple soil cone penetrometer measurements and expressed as cone index (CI). Corn, wheat, and soybean yields were depressed in grid cells with CI_avg ≥ 1.5 MPa (218 psi) prior to application of tillage treatments at sites 1 and 3, whereas at site 2, where most of the highest average CI values ranged from 1.44 …

Controller Area Network Based Distributed Control For Autonomous Vehicles, Matthew J. Darr, Timothy S. Stombaugh, Scott A. Shearer

Biosystems and Agricultural Engineering Faculty Publications

The goal of this project was to evaluate the potential of a controller area network (CAN bus) to be used as the communication network for a distributed control system on an autonomous agricultural vehicle. The prototype system utilized microcontroller-driven nodes to act as control points along a CAN bus. Messages were transferred to the steering, transmission, and hitch control nodes via a task computer. The task computer utilized global positioning system data to generate appropriate control commands. Laboratory and field testing demonstrated that each of the control nodes could function simultaneously over the CAN bus. Results showed that the task …

The Kentucky Agricultural Economic Outlook For 2005, Linda Inman, A. Lee Meyer

Kentucky Agricultural Economic Outlook

No abstract provided.

Aeration Strategies And Fan Cost Comparisons For Wheat In Mid-South Production Regions, Thomas C. Bridges, Michael D. Montross, Samuel G. Mcneill

Biosystems and Agricultural Engineering Faculty Publications

Numerous factors influence the sizing of aeration fans for summer-harvested crops. Thirty years of weather data for Lexington, Kentucky, were analyzed and the cost of aeration was compared for two axial fans (afan1, afan2) and one centrifugal fan (cfan1). Aeration costs were defined as the sum of the following components: the cost of owning the fan, the cost of electricity for operating the fan, a cost for wheat shrinkage during aeration, and a cost for dry matter loss (DML). The fans were selected to deliver airflow rates of approximately one, two, and three times the recommended aeration rate of 0.11 …