Plant Sciences Commons^™

The Effect Of Photocatalytic Titanium Dioxide And Ultraviolet B Radiation On Sclerotinia Homoeocarpa Growth And Pathogenicity, Chun Hu

Masters Theses

Photocatalytic TiO₂ [titanium dioxide] generates strong oxidative effects when illuminated with ultraviolet (UV) light with wavelengths of less than 385 nm. UVB has wavelengths ranging from 280 to 315nm. Previous research indicates the oxidative species and UVB radiation can react and cause cellular damage to microorganisms, which may reduce Sclerotinia homoeocarpa growth and help to control dollar spot disease development. The objectives of this study were to investigate the interactions of TiO₂ and UVB radiation, both in vitro and in vivo, on the growth and development of dollar spot. Factorial treatments consisting of five rates of TiO₂ and three doses …

Detection Of Soybean Amino Acid Qtls And Seed Yield Qtls Using Selective Genotyping, Benjamin David Fallen

Doctoral Dissertations

The U.S. Census Bureau projects the world’s population will top more than nine billion by 2050. Today, soybeans account for 56 % of the world oilseed production and 68 % of the world protein meal consumption, with U.S. soybean production accounting for 33 % of the world soybean production. So, to meet the demand of the world’s growing population and of the livestock industry improvements in both the composition and the yield of soybean is essential.

The primary objective of this project was to use molecular markers to identify genomic regions associated with amino acid composition and yield in soybean. …

Anaerobic Soil Disinfestation: Evaluation Of Anaerobic Soil Disinfestation (Asd) For Warm-Season Vegetable Production In Tennessee, David Grant Mccarty

Masters Theses

Anaerobic soil disinfestation (ASD) is a non-chemical, pre-plant soil treatment recently developed for control of pests such as soilborne plant pathogens, plant-parasitic nematodes, and weeds in specialty crop systems. Soil treatment by ASD includes incorporating a labile carbon (C) source, tarping with plastic, and irrigation of the topsoil to saturation to facilitate the development of strongly anaerobic soil conditions driven by soil microbes. Processes occurring during the anaerobic decomposition of the added C source have been reported control plant pests. The goal of this project was to evaluate and adapt the ASD procedure to environmental conditions and production systems in …

Applicability Of Pigment Compounds For Reducing Light Stress In Bentgrass, Gregory Keith Bartley

Masters Theses

Chlorinated copper phthalocyanine (Signature) and pulverized cells of Chlorella vulgaris (Chlorella) were evaluated in a controlled environment for their ability to act as photoprotectants under supraoptimal levels of ultraviolet (UV) and photosynthetically active radiation (PAR) when applied to plant leaves. Plant pigment changes were documented using High Performance Liquid Chromatography following 1 week of exposure to supraoptimal light in two separate experiments incorporating UV (106.6 μmol m-2 s-1) and PAR (760.6 μmol m-2 s-1) over a 12h photoperiod. Supraoptimal levels of UV and PAR light were found to cause significant reductions in Agrostis palustris chlorophyll and carotenoid leaf pigment levels. …

Heritability And Genetic Gain Of Seed Protein, Oil, And Yield Among Ril Of Soybean, Benjamin T. Wiggins

Masters Theses

Soybean is a remarkable crop that is used in many aspects of our everyday lives. The seed protein is used primarily for livestock feed, though it is becoming more available as a meat substitute for human consumption. Soybean oil is used in many products such as plastics, foods, and industrial products. Seed yield is the major trait that is selected for in a breeding program. A population of 239 F₄ derived RIL from the cross of USG 5601T × U99-310255 was used to calculate heritability estimates by parent offspring regression and on an entry mean basis. This population was …

Utility Of Aminocyclopyrachlor For Control Of Horsenettle And Tall Ironweed In Cool-Season Grass Pastures, William Paul Phillips

Masters Theses

Previous research has shown that management of horsenettle (Solanum carolinense) and tall ironweed (Vernonia gigantea) in cool-season grass pastures and hayfields is difficult. Therefore, research was conducted at Alcoa, Fork Creek, Greenback, Maynardville, and Pulaski, Tennessee, and at London, Kentucky, in 2010 and 2011 to examine efficacy of aminocyclopyrachlor on these two perennial weeds. Research was conducted on naturally-occurring infestations of each weed. Treatments were: aminocyclopyrachlor (49 g ai/ha) with and without 2,4-D amine (371 g ai/ha), aminocyclopyrachlor (98 g ai/ha) with and without 2,4-D amine (742 g ai/ha), and aminopyralid (88 g ai/ha). Treatments were …

Cotton (Gossipium Hirsutum L.) Response To Irrigation And Environment In A Short Season Climate, Matthew Scott Wiggins

Masters Theses

Research was conducted in 2010 and 2011 at the West Tennessee Research and Education Center in Jackson, TN to investigate water deficit and irrigation response in cotton to provide a better understanding of physiological growth changes and yield impact on the crop grown in soils of varying depth to a sandy layer. The deep soil yielded more vegetative mass when compared with the shallower soil. This is also true when applying higher rates of irrigation where plants grew two more nodes of growth and 15.2 centimeters of plant height. Time to cotton maturity was delayed seven days in the deep …

Molecular Marker Assisted Development And Stability Analysis Of Low Phytate, High Inorganic Phosphorus Soybean [Glycine Max (L.) Merrill], Suzannah Joy Wiggins

Masters Theses

Phytate [myo-inositol 1,2,3,4,5,6-hexakisphosphate] is a mixed cation salt of phytic acid which binds to other minerals, in many field crops including soybean [Glycine max (L.) Merr.]. Livestock with monogastric digestive systems lack the ability to break bonds between phytate and these minerals, causing phytate phosphorus (P) to be excreted in the waste and contributing to possible P and other mineral deficiencies. Discovery of single sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers associated with low phytate QTL (cqPha-001 and cqPha-002) have aided in development of low phytate soybean lines. The objectives of this study were …

Integrated Strategies For Controlling Warm-Season Turfgrass Weeds, Matthew Thomas Elmore

Masters Theses

Herbicidal inhibitors of 4-hydroxyphenylpyruvate dioxygenase (HPPD) such as mesotrione, topramezone and tembotrione were evaluated in greenhouse experiments for activity against bermudagrass. While topramezone and tembotrione exhibited greater activity than mesotrione, none of these herbicides provided acceptable bermudagrass control. These herbicides reduced leaf tissue chlorophyll and carotenoid pigment concentrations in bermudagrass. Changes in turfgrass pigmentation were quantified using HPLC analogy as well as evaluations of visual bleaching and measurements of chlorophyll fluorescence yield (F_v/F_m). Results indicated that these more expeditious methods of evaluating HPPD-inhibiting herbicide activity (visual evaluations and F_v/F_m) cannot be used …

Impact Of Switchgrass Bioenergy Feedstock Production On Soil Carbon Dioxide Flux And Below Ground Soil Organic Carbon Storage In East Tennessee, Leah Denise Soro

Masters Theses

Bioenergy production from switchgrass has shown promise in restoring degraded soils and helping to mitigate greenhouse gas (GHG) emissions. CO₂ loss and C-sequestration in soils are important topics for research to better understand the environmental impacts of bioenergy crops. The need for more thorough research of the carbon cycle in soils used for bioenergy production precipitated the primary interest of this study. The specific objectives of this study were 1) to measure SOC under switchgrass production in order to predict storage of carbon in soils based on previous cropping history, land management, soil physical characteristics, and time; and to …

Pb1742 Tennessee Cotton Variety Test Results 2011, Chris L. Main, Fred L. Allen

Field & Commercial Crops

Version 5.0

W283 Should Tennessee Tobacco Growers Invest In Irrigation, Fertigation Or Plastic Mulch?, Brian G. Leib, Eric F. Caldwell, Hubert J. Savoy, John R. Buchanan

Field & Commercial Crops

Version 2.0

Establishment And Persistence Of Legumes In Switchgrass Biomass And Forage/Biomass Production Systems, Kara Spivey Warwick

Masters Theses

Switchgrass, Panicum virgatum, is being developed as an economically and ecologically sustainable biomass crop. Nitrogen is considered one of the most limiting inputs of switchgrass. Alternatives to synthetic nitrogen fertilization may be nitrogen-fixing legumes interseeded into switchgrass. The objectives of this research were: (1) develop efficient legume management strategies for switchgrass production systems, (2) evaluate and identify cool and warm-season legumes that can be grown compatibly with switchgrass, (3) determine whether switchgrass yields are increased by legume N-fixation, and (4) determine N-fixation of common (Vicia sativa) and hairy vetch (Vicia villosa).

This study examined the …

The Effects Of Living Mulches On Organic, Reduced-Till Broccoli Growth And Management, Sarah Elizabeth Broughton

Masters Theses

Conservation tillage programs have been successfully implemented for many agronomic cropping systems, but adoption of reduced tillage for vegetable crops has been slow. As many conventionally managed conservation tillage programs rely on synthetic herbicides for clean cultivation, alternative methods must be devised to suppress weed pressure and reduce reliance on mechanical cultivation to aid in the development of reduced tillage programs for organic cropping system. Strip tillage is a reduced tillage method that is well suited to vegetable crop production, and the utilization of cover crops and living mulches between rows provides a viable weed management option for organic systems. …

Control Of Glyphosate Resistant Horseweed (Conyza Canadensis) With Saflufenacil And Tank-Mixture Partners., Brock Steven Waggoner

Masters Theses

Field and labratory studies were conducted to determine the efficacy of saflufenacil alone and with mixture partners for burndown. Field studies were conducted in 2009 and 2010 to evaluate saflufenacil in mixtures with glyphosate, glufosinate, or paraquat for control of glyphosate-resistant (GR) horseweed prior to planting cotton. Saflufenacil and saflufenacil mixtures were applied 7 days before planting (DBP). Saflufenacil at 25 and 50 g ai ha-1 in mixture with all three non-selective herbicides provided similar GR horseweed control when compared to the current standard of glyphosate plus dicamba. Control of GR horseweed was also not different at the 25 and …

Investigating Cold Hardiness And Management Practices Of Warm-Season Putting Green Species In The Transition Zone, John M. Kauffman

Doctoral Dissertations

Warm-season turf species are becoming increasingly popular for putting green use in the transition zone. Ultradwarf bermudagrass (Cynodon dactylon (L.)  C. transvaalensis Burtt-Davy) is the prevalent warm-season putting green species, but seashore paspalum (Paspalum vaginatum Swartz) and ‘Diamond’ zoysiagrass [Zoysia matrella (L.) Merr.] may also be grown in the transition zone. Warm-season species are susceptible to winter injury and may require different management regimes than cool-season species. Therefore, the objectives of this research were to assess the impacts of various management practices on warm-season putting green species and characterize the physiological basis for differences in freeze tolerance of various …

Effects Of No-Tillage On Crop Yields And Net Returns Across The United States, Dustin Kevin Toliver

Masters Theses

Farmers are always looking for ways to increase yields and profits and no-tillage may be a way to achieve this goal. However, a comprehensive study of the performance of no-tillage yields relative to conventional tillage yields and their net returns is lacking. This study evaluated the potential factors that influence differences in conventional tillage and no-tillage yields and net returns as explained by such factors as time, crop, precipitation, soil texture and geographic region. Data were collected from 442 paired tillage experiments growing corn, soybeans, cotton, oats, wheat and sorghum published in three refereed journals. Data were evaluated using a …

Effects Of Trinexapac-Ethyl And Winter Overseeding On The Morphological Characteristics And Traffic Tolerance Of Bermudagrass Cultivars, William D. Haselbauer

Masters Theses

Common bermudagrass [Cynodon dactylon (L.) Pers.] and hybrid bermudagrass [C. dactylon (L.) Pers. X C. transvaalensis Burtt-Davy] are some of the most common turfgrasses used on athletic fields. Subsequently, the traffic tolerance of commercially available cultivars and the effects of trinexapac-ethyl (TE) on bermudagrass athletic fields with or without perennial ryegrass are often limited. A two year study at the University of Tennessee was conducted under simulated athletic field traffic to evaluate the performance of bermudagrass cultivars as affected by TE and overseeding. Bermudagrass cultivars evaluated were Tifway, Riviera, Patriot, and Celebration. TE treatments consisted of an untreated …

Classification And Fertility Of Soils In The Big South Fork National River And Recreation Area Based On Landscape Position And Geology, Ryan H. Blair

Masters Theses

The Big South Fork National River and Recreation Area encompasses more than 50,585 hectares (125,000 acres) of the Cumberland Plateau along the border of Tennessee and Kentucky. Highly dissected and steep terrain have made accessibility to much of the park limited, thus little work has been done to investigate the formation of these soils. Seven native soil profiles were selected for chemical and physical analysis representing Pennsylvanian-aged acidic sandstone and shale geology and landforms. The objectives of this study included the characterization of selected native profiles by physical and chemical analysis, as well as classification using US Soil Taxonomy, to …

Sp341-W-Insects In Grain Bins, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

One of the most common insects in stored grain is the Indian-meal moth, Plodia interpunctella (Hubner). These moths are called “flour moths” in Tennessee because they feed on flour or milled products. In farm grain bins, they prefer broken grains or grains damaged by other pests and seldom attack sound grain kernels. They cause problems by spinning webbings as immature. This causes lower quality in stored grain.

Sp721 Sunflower: An Alternative Crop For Tennessee Producers - Production Guidelines And Tennessee Hybrid Trials, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

Tennessee producers are interested in crops that can be grown to diversify and/or complement their current cropping systems that include corn, cotton, soybeans and wheat. There is a growing demand for birdseed, and sunflower is an important component of that feed, either as a sole ingredient or in a blend with other seeds such as millet, corn, sesame, sorghum, wheat and oats. Sunflower oil is used for human consumption and is also a suitable feedstock for biodiesel. An increasing demand for biodiesel will increase the demand for oilseed crops such as sunflower. Thus, there may be increased opportunities for some …

Sp721-Sunflower: An Alternative Crop For Tennessee Producers - Production Guidelines And Tennessee Hybrid Trials, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

Tennessee producers are interested in crops that can be grown to diversify and/or complement their current cropping systems that include corn, cotton, soybeans and wheat. There is a growing demand for birdseed, and sunflower is an important component of that feed, either as a sole ingredient or in a blend with other seeds such as millet, corn, sesame, sorghum, wheat and oats. Sunflower oil is used for human consumption and is also a suitable feedstock for biodiesel. An increasing demand for biodiesel will increase the demand for oilseed crops such as sunflower. Thus, there may be increased opportunities for some …

Rr10-03-2009 Soybean Variety Performance Tests In Tennessee, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

No abstract provided.

Sp290-K The Hessian Fly In Wheat, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

The Hessian fly is a pest of winter wheat in Tennessee and other wheat-growing states. This pest caused disastrous losses in Tennessee wheat in the mid- 1980s. Later planting of wheat and the use of wheat varieties resistant to Hessian fly minimized economic losses from this pest. In the coming years, potential economic losses from Hessian fly could increase due to the lack of resistance varieties.

In 2009, very little attention was given to Hessian fly infestations. However, there are some varieties with moderate resistance to biotype L Hessian fly. None are completely resistant. Some of the better methods to …

Pb1580 2010 Weed Control Manual For Tennessee, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

This manual contains the 2010 University of Tennessee weed control recommendations for corn, grain sorghum, cotton, soybeans, burley and dark tobacco, wheat, forage crops, sunflowers and farm ponds. These recommendations are based on results of research and demonstrations conducted by the Agricultural Experiment Station and the Agricultural Extension Service. Decisions regarding recommendations are made by the University of Tennessee Weed Control Committee and are based on available data at various locations in the state.

This publication contains pesticide recommendations that are subject to change at any time. The recommendations in this publication are provided only as a guide. It is …

Impacts Of American Student Teachers On Twelve Community Members In A Rural New South Wales Community Australia: A Qualitative Study, Tera Shenae Bunch

Masters Theses

The purpose of this study was to evaluate the influences of American student teachers on a rural community in New South Wales, Australia. The study analyzed interviews with twelve participants of the American student teacher program in A Rural New South Wales community, Australia. Two researchers worked together to complete this study. Both researchers were student teachers with the New South Wales community for ten weeks and taught Agriculture in one the community‟s two high schools. After allowing one year to pass, researcher one returned to the community to interview twelve individuals involved with the program. The interviewed participants were …

Sp618-2010-2009 Corn Hybrid & Sweet Sorghum Silage Tests In Tennessee, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

No abstract provided.

Sp639-2010-2009 Grain Sorghum Hybrid Tests In Tennessee, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

No abstract provided.

Pb1768 2010 Insect Control Recommendations For Field Crops –, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

An Integrated Pest Management (IPM) program integrates control tactics including cultural practices, variety selection, biological control and insecticides to manage insect pest populations so that economic damage and harmful environmental side effects are minimized. Insecticides should only be used on an as-needed basis; therefore, insect scouting must be conducted regularly throughout the season to determine if an insecticide application is warranted.

W229-Interpreting Mehlich 1 And 3 Soil Test Extractant Results For P And K In Tennessee, The University Of Tennessee Agricultural Extension Service

Field & Commercial Crops

The Mehlich 1 and 3 soil test extractants are the most widely used in laboratories of the southern United States today. Tennessee began using the Mehlich 1 extractant in December, 1981. Existing soil test calibration data in Tennessee are based on the Mehlich 1 soil test extractant,1,2 which became available in 1953.