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Forage News [2022-01], Department Of Plant And Soil Sciences, University Of Kentucky Jan 2022

Forage News [2022-01], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.


An Examination Of Organic Options In Tomato Systems And Their Use As Alternatives To Copper-Based Products, Erica Ann Fealko Jan 2022

An Examination Of Organic Options In Tomato Systems And Their Use As Alternatives To Copper-Based Products, Erica Ann Fealko

Theses and Dissertations--Plant Pathology

Organic farming is an ever-increasing segment of tomato production. Currently, limited information is available which directly compares conventional to organic treatment programs for disease control in tomato production. Furthermore, many methods available rely on the use of copper products which may be contribute to high Cu levels in agricultural soils. In this study, the efficacies of current conventional and organic methods were compared. In addition, newer disease-control programs, with and without copper were examined, which potentially could reduce over-reliance on copper products.

Standard organic and conventional spray programs were conducted over a four year period targeting two pathogens, Alternaria tomatophila …


Regulatory Mechanisms In Arabidopsis Embryogenesis, Sanjay Joshi Jan 2022

Regulatory Mechanisms In Arabidopsis Embryogenesis, Sanjay Joshi

Theses and Dissertations--Plant and Soil Sciences

Plants have amazing regeneration properties with single somatic cells, or groups of cells able to give rise to fully formed plants. One means of regeneration is Somatic Embryogenesis (SE), by which an embryonic structure is formed that “converts” into a plantlet. Somatic embryogenesis has been used as a model for zygotic processes that are buried within layers of maternal tissues. Understanding mechanisms of somatic embryo induction and development are important as a more accessible model for seed development. We rely on seed development not only for most of our caloric intake, but also as a delivery system for engineered crops …


The Impact Of Plant Secondary Metabolites On Auxin And Cytokinin Signaling, Timothy E. Shull Jan 2022

The Impact Of Plant Secondary Metabolites On Auxin And Cytokinin Signaling, Timothy E. Shull

Theses and Dissertations--Plant and Soil Sciences

Secondary metabolites are a broad class of specialized compounds that mediate plant-environment interactions and mitigate stress. It is increasingly clear that many phenylalanine-derived secondary metabolites are nearly indispensable for plant survival and that plants adjust their growth according to their secondary metabolic outputs. Consequently, many phenylalanine-derived secondary metabolites have influence over hormone activity. For instance, multiple phenylpropanoid intermediates and catecholamines alter the sensitivity of plants to the central hormone auxin, which in concert with cytokinin directs most aspects of plant growth and development. This dissertation reviews previous research on the influence of phenylpropanoid intermediates and catecholamines on plants, with a …


An Improved Understanding Of Diplodia Ear Rot In Kentucky Corn, Nolan Ryan Anderson Jan 2022

An Improved Understanding Of Diplodia Ear Rot In Kentucky Corn, Nolan Ryan Anderson

Theses and Dissertations--Plant Pathology

Stenocarpella maydis and Stenocarpella macrospora are both causal agents of Diplodia ear rot (DER) of corn in the U.S. The current prevalence and distribution of each is unknown worldwide. Signs and symptoms of DER include white mold on and between kernels, bleached husks, and pycnidia visible in the cob pith. The term hidden Diplodia describes when no mycelia or bleached husk is present, but pycnidia are still visible inside the cob. This phenomenon is reported to be caused by late infections of Stenocarpella spp. New fungicide nozzle technology has been promoted to increase spray coverage in the lower canopy, which …


Optimizing Nitrogen Management In Winter Wheat Production Systems For Improved Bread Baking Quality, Ammar Sadiq Mahdi Al Zubade Jan 2022

Optimizing Nitrogen Management In Winter Wheat Production Systems For Improved Bread Baking Quality, Ammar Sadiq Mahdi Al Zubade

Theses and Dissertations--Plant and Soil Sciences

In Kentucky, there is growing interest among farmers to produce high protein and strong gluten wheat that is suitable for bread baking to meet the demand of local artisanal bakers. Soft red winter wheat (SRW) is the most commonly wheat grown in the state and throughout the Southeastern US. Flours produced from SRW are relatively low in grain nitrogen (N) due to the region’s moderate winters and warm humid conditions during grain filling. As such, SRW is used in baking products where lower protein flours are preferred, such as cookies, cakes, pastries and crackers. Unlike SRW, hard red winter wheat …


Manipulating Species Diversity: Environmental Impacts In Row Crop, Livestock, And Grassland Agroecosystems, Alayna A. Jacobs Jan 2022

Manipulating Species Diversity: Environmental Impacts In Row Crop, Livestock, And Grassland Agroecosystems, Alayna A. Jacobs

Theses and Dissertations--Plant and Soil Sciences

The diversity of living species in an agroecosystem affects both natural resources and agricultural production efficiency. The rise of managed plant monocultures has allowed agricultural yields to increase over time. However, simplifying agroecosystems affects the capacity of the system to sustainably provide clean air, water, and productive soils essential for continued food and fiber production. This dissertation manipulates species diversity in row crop and forage agroecosystems prevalent in the Eastern United States and tracks the associated environmental and agricultural production consequences.

In row crop agroecosystems, increasing plant diversity with winter cover crops has been suggested as a strategy to increase …


An Evaluation Of Eragrostis Tef For Future Cultivar Development, Eric Wayne Luteyn Jan 2022

An Evaluation Of Eragrostis Tef For Future Cultivar Development, Eric Wayne Luteyn

Theses and Dissertations--Plant and Soil Sciences

The many benefits of utilizing teff (Eragrostis tef) as small grain is well documented in journal publications. Over time the domestication of this species has become essential to the diets of the local population and the livestock living in the African highlands. Current research points to a high diversity of trait characteristics found in many teff populations and the potential utilization of these traits to increase desirable characteristics in both grain and forage varieties. With the overarching goal of adding to what is already known about teff, this study evaluates the different traits that are of interest to …


The Role Of Nitric Oxide In Inter- And Intra- Cellular Signaling In Plant Defense, Fan Xia Jan 2022

The Role Of Nitric Oxide In Inter- And Intra- Cellular Signaling In Plant Defense, Fan Xia

Theses and Dissertations--Plant Pathology

Plants have evolved a sophisticated immune system to defend themselves against pathogens. This immune response can be triggered in response to pathogen-associated molecular patterns (PAMP) or specialized effectors that are recognized by the plant resistance (R) proteins. The latter, commonly referred to as effector-triggered immunity (ETI), is well known to induce broad-spectrum resistance throughout the plants. This phenomenon known as systemic acquired resistance (SAR) is regulated by several chemical signals including salicylic acid (SA), and free radical nitric oxide (NO) and reactive oxygen species (ROS). These signals operate in two parallel branches with NO/ROS functioning downstream of pipecolic acid (Pip) …


Epidemiology And Management Of Frogeye Leaf Spot Of Soybean: Damage Thresholds, Efficacy And Profitability Of Foliar Fungicides, Jhonatan Paulo Barro Jan 2022

Epidemiology And Management Of Frogeye Leaf Spot Of Soybean: Damage Thresholds, Efficacy And Profitability Of Foliar Fungicides, Jhonatan Paulo Barro

Theses and Dissertations--Plant Pathology

Frogeye leaf spot (FLS), caused by Cercospora sojina, is an economically important disease of soybean in many parts of the world where soybean is grown, including the United States. A meta-analytic approach was used to summarize a data set of 66 uniform field research trials conducted to evaluate fungicide efficacy against FLS on soybean. The dataset spanned 10 years (2012 to 2021) of experiments conducted across eight states in the U.S., including Alabama, Arkansas, Illinois, Iowa, Kentucky, Louisiana, Mississippi and Tennessee. First, the relationship between FLS severity and soybean yield was investigated. A significant negative slope obtained through random …


The Site Evaluation Of Quercus Alba Metabolites, Zachary Alexander Byrd Jan 2022

The Site Evaluation Of Quercus Alba Metabolites, Zachary Alexander Byrd

Theses and Dissertations--Plant and Soil Sciences

Quercus alba has been the prominent tree species utilized in the spirits industry for decades. Of its many qualities, the ability to impart desirable flavors on spirits combined with its natural abundance makes it the ideal choice for barrels. Creating barrels is a uniform process, but variability still exists in aged spirits even when all other parameters are controlled. In this thesis, I explore how the origin of Quercus alba influences metabolite variability.

Quercus alba is a resilient species that can grow in many climates. This is seen through Quercus alba’s vast growing range, of which barrel quality white oak …


Remote Sensing For Quantifying C3 And C4 Grass Ratios In Pastures, Jordyn Alyssa Bush Jan 2022

Remote Sensing For Quantifying C3 And C4 Grass Ratios In Pastures, Jordyn Alyssa Bush

Theses and Dissertations--Plant and Soil Sciences

The following studies investigate the accuracy and practicality of exploiting the color dichotomy present between C3 and C4 grass species to estimate their respective proportions from drone or camera captured imagery. Understanding the proportions of C3 and C4 grasses in pastures is vital to sound decision making for livestock production. The ability to monitor these proportions remotely will also allow for large scale monitoring as well as detection of changes in botanical composition over time and in response to weather events, management, or climate change. A free green canopy cover (GCC) analyzing software, Canopeo, was used …