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Forage News [2022-05], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.

Investigation Into The Responses Of Physcomitrella Patens To Herbivory And The Influence Of Light On The Production Of Defense Compounds, Matthew Morris

Undergraduate Honors Thesis Collection

Plant defense mechanisms are well studied in many agriculturally relevant crops such as corn and tomatoes. Though less studied, the more ancestral nonvascular plants may be able to provide insights into the origin and working of modern plant defense systems. In this study, the bryophyte Physcomitrella patens was researched and the role of the jasmonic acid pathway in response to herbivory was investigated. Additionally, the impact of light intensity on the efficacy of this pathway was to be determined. After exposing the moss to various chemical elicitors and mechanical wounding, the activity of proteins produced in the JA pathway was …

Native And Non-Native Ant Impacts On Soil Microbes, Hannah A. Stewart

Biology Theses

Organisms produce chemical weapons for defense, but target organisms can develop resistance. In their introduced range, non-native species may bring “novel weapons” against which native organisms have not co-evolved resistance. The invasive European fire ant (Myrmica rubra) may have brought antimicrobial secretions to the Northeastern United States that are novel weapons against native fungal and bacterial soil organisms. I hypothesized that M. rubra would better inhibit seed pathogens resulting in greater emergence of native myrmecochorous Viola sororia seeds and, as a side effect, more strongly inhibit arbuscular mycorrhizal fungi than a native seed dispersing ant (Aphaenogaster picea …

Elucidating The Cellular Physiology Of Glyphosate Resistance In Palmer Amaranth (Amaranthus Palmeri) Using Integrated Omics Approaches, Pawanjit Kaur Sandhu

All Theses

The evolution of resistance to herbicides in weeds poses a major threat to agricultural production systems. To date, herbicide resistance has been reported against 21 modes of action in 266 weed species across 71 countries. More than 50 weed species have developed resistance against glyphosate, the most widely used herbicide worldwide. Although several mechanisms of glyphosate resistance have been discovered, our understanding of alterations in the cellular physiology of glyphosate-resistant weed biotypes, and the induction of the resistance mechanisms remains limited. This knowledge is critical to developing sustainable weed management practices and for a comprehensive understanding of plant stress adaptations. …

Evaluation, Characterization, And Utilization Of Weed-Suppressive Sweetpotato Cultivars For Sustainable Weed Management, Isabel Schlegel Werle

Graduate Theses and Dissertations

Sweetpotato (Ipomoea batatas L.) is a low-technology, subsistence crop that enhances food and nutrition security particularly in developing nations. Weed interference with the crop can reduce sweetpotato storage root yields and product quality. Current weed management practices in sweetpotato include PRE or POST herbicides application, cultivation, mowing, or handweeding. Unlike row crops, herbicide options for sweetpotato are few; therefore, alternative weed control practices are needed. The overall objective of this research was to determine the weed suppressive ability of several sweetpotato cultivars. This research also provides information about cover crop use for weed suppression in sweetpotato production in Arkansas. Field …

Using Thermal Units To Predict Biomass Accumulation And Total Nitrogen Uptake For Cover Crops In Arkansas, Mila Victório Pessotto

Graduate Theses and Dissertations

Including cover crops in agricultural production systems is an important management practice. Cover cropping can improve soil health, increase plant-available nitrogen (N), provide surface residue to prevent erosional soil loss, increase water infiltration, and increase weed suppression. Cover crops growth can be predicted using thermal days or growing degree days [GDD] similar to commodity crops such as corn (Zea mays L.) or rice (Oryza sativa). Growing degree day calculations are a well-known tool to predict crop growth stage or development stage and can be adapted for use in any plant species, including cover crops. Identifying and developing the relationship between …

Breeding Soybean [Glycine Max (L) Merr.] Under Reduced Irrigation, Francia Seconde Ravelombola

Graduate Theses and Dissertations

Soybean [Glycine max (L) Merr.], a legume species native to East Asia in the Fabaceae family, ranks among the most important food crops in the world. It is widely grown and known for its high protein and oil concentration. Soybean is valuable because its seeds have multiple applications in food, feed, pharmaceutical, and industrial enterprises. Even though seed yield is the most important trait, breeders have recently given a significant attention to quality traits, such as high protein or modified oil concentration. Soybean seed protein inheritance has been extensively studied; however, genetics of high-protein ‘BARC-7’ soybean are still unknown.On the …

It Takes Brains: Cultivating The Learning Process For Effective Science Communication, Amy D. Hauver

Doctor of Plant Health Program: Dissertations and Student Research

Learning is a complex, subjective process. An important perspective on learning is that anyone, regardless of their level of education, can participate in learning about science and contribute to their community. The public increasingly looks towards online resources to find answers to challenges, so it is necessary that people become empowered to take information about issues rooted in science and apply them to their own lives and communities. In my experiences as a learner and educator, understanding the learning process provides a framework to design successful learning environments.

Since the brain is the organ most closely associated with the process …

Site-Specific Pest Management In Nebraska Corn And Soybean Production Systems, Zachary D. Rystrom

Doctor of Plant Health Program: Dissertations and Student Research

Site-specific management (SSM) is widely used by farm producers to fertilize their fields. However, whole field management is currently practiced in integrated pest management (IPM). Site-specific management and agricultural technology can improve IPM especially when precision application of inputs can reduce selection pressure on pest populations, benefit the environment, or save costs of inputs. There is potential for site-specific pest management (SSPM) where pests, or environments vary spatially, and recommended management practices can be applied with precision. Three case studies are evaluated for SSPM to be applied in Nebraska corn and soybean production systems including corn rootworm, preemergence herbicides, and …

Examining The Invasion Of Bush Honeysuckle Through A Phylogenetic Analysis, Phoebe Bruffett

Biological Sciences Undergraduate Honors Theses

The mechanisms underlying the continual spread of invasive plants within their respective non-native ranges is a major focal point to invasion research. Many theories have been proposed to understand these invasions, each with different implications for the predicted range for invasive plants. Lonicera maackii provides an exceptional opportunity to examine the effectiveness of these theories to explain the trends of invasive plants. Lonicera maackii is native to eastern Asia, but has invaded much of the eastern United States, presenting a severe threat to the health of forest and other natural areas. Recent analysis of the climatic envelopes uncovered a significant …

The Synchronization Of Nocturnal Pollinator Behavior And Apple Flower Nectar Production, Madison Jennings

Biological Sciences Undergraduate Honors Theses

Insects perform an essential ecological service by facilitating the pollination of crops for food production worldwide. Recent declines in diurnal bee populations threaten food security and has led to growing concerns about existent pollination methods. Pollination contributions by native nocturnal insects have been documented to occur in a variety of systems, thought to be supported by the plant’s attractant and reward system. If this is the case, pollination of flowers by nocturnal vectors may be influenced by circadian cycles of nectar production and insect activity. To test this hypothesis, we recorded insect abundance of nocturnal pollinators periodically throughout the night …

Regional Plant Community Differences In The Nebraska Sandhills, Travis Millikan

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The Nebraska Sandhills is very valuable to the state of Nebraska, representing one of the most in-tact and largest grassland ecosystems in temperate regions in the world. Rangeland managers must understand plant community dynamics across the Sandhills to better inform management decisions. The first objective of this study was to evaluate plant community variability on upland Sands ecological sites across different precipitation zones in the Nebraska Sandhills. The second objective of our study was to utilize the Rangeland Analysis Platform (RAP) to examine spatial and temporal variability in biomass production and cover on pastures of ranches analyzed in the first …

Through The Leaves: Understanding Population Genetic Structure Of Clematis Morefieldii, Keith Andrew Greenway

Honors Capstone Projects and Theses

No abstract provided.

Oestrogenic Subterranean Clover Guide. Identification And Remediation, Kevin J. Foster, Megan H. Ryan, Daniel R. Kidd

Bulletins 4000 -

Subterranean clover (subclover, Trifolium subterraneum L.) is an annual pasture legume that provides high quality feed for livestock. It is estimated to be sown over 30 million hectares across southern Australia, with cultivars developed for the low, medium and high rainfall zones. Unfortunately, some older cultivars contain high levels of phytoestrogen which can affect the reproductive system of sheep and cause other health issues. This became a significant issue for sheep producers from the 1940s as new land was cleared and sheep grazed subclover-dominant pastures. There was a collection of livestock issues observed and these were grouped together under the …

Harvester Ant (Pogonomyrmex Sp.) Seed Preferences And Distribution In A Suburban Setting, Lilly V. Elliott

Theses and Dissertations

Harvester ants (Pogonomyrmex sp.) are omnivorous ants native to Texas and are the main food source for the threatened Texas Horned Lizard (Phrynosoma cornutum). Little research has been conducted on harvester ants in the Lower Rio Grande Valley (LRGV) and their interactions with their environment. For this purpose, a variety of experiments were conducted to better understand these interactions and preferences. In CHAPTER I, suburban harvester ants were exposed commonly used cover crop seeds in the LRGV and inoculated seeds via seed depots over the course of 24 hours. We found that harvester ants do …

Temporal Dynamics And Seed Dispersal In Plant-Frugivore Communities Of The Dominican Republic, Spencer Christian Schubert

Biological Sciences Theses & Dissertations

Plant-animal mutualisms are a foundational component of biodiversity in terrestrial ecosystems. Most tropical forest plants have adapted to produce fleshy fruits to attract frugivorous animals to disperse seeds. Interaction patterns among plant taxa and their seed dispersers are driven by a complex suite of factors involving their evolutionary history and environmental context, and the structure of these mutualistic networks are theoretically tied to their ecological function. I carried out a series of field studies to investigate the temporal dynamics of mutualistic interactions of plant and avian frugivore communities in the central Dominican Republic and how their characteristics affect seed dispersal …

Chromosome-Level Thlaspi Arvense Genome Provides New Tools For Translational Research And For A Newly Domesticated Cash Cover Crop Of The Cooler Climates, Adam Nunn, Isaac Rodríguez-Arévalo, Zenith Tandukar, Katherine Anna Frels, Adrián Contreras-Garrido, Pablo Carbonell-Bejerano, Panpan Zhang, Daniela Ramos Cruz, Katharina Jandrasits, Christa Lanz, Anthony Brusa, Marie Mirouze, Kevin Dorn, David W. Galbraith, Brice A. Jarvis, John C. Sedbrook, Donald L. Wyse, Christian Otto, David Langenberger, Peter F. Stadler, Detlef Weigel, M. David Marks, James A. Anderson, Claude Becker, Ratan Chopra

Department of Agronomy and Horticulture: Faculty Publications

Thlaspi arvense (field pennycress) is being domesticated as a winter annual oilseed crop capable of improving ecosystems and intensifying agricultural productivity without increasing land use. It is a selfing diploid with a short life cycle and is amenable to genetic manipulations, making it an accessible field-based model species for genetics and epigenetics. The availability of a high-quality reference genome is vital for understanding pennycress physiology and for clarifying its evolutionary history within the Brassicaceae. Here, we present a chromosome-level genome assembly of var. MN106-Ref with improved gene annotation and use it to investigate gene structure differences between two accessions (MN108 …

Opportunities For Optimal Apple Production Management In Arid Conditions, Sam Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Apple trees are susceptible to biotic and abiotic stresses in the Intermountain West. The arid climate along with non-ideal soils make apple production challenging. Also, as high-quality agricultural land is developed, crop production gets pushed to land that often is saline. Apple trees grow poorly in saline soils. If apples are going to be grown in Utah, rootstocks must be identified that will tolerate saline soils. The USDA rootstock breeding program produced some rootstocks that may show salt tolerance. This project assessed the salt tolerance of these apple rootstocks in the greenhouse and in the field. Test rootstocks were compared …

Winners And Losers In Dryland Reforestation: Species Survival, Growth, And Recruitment Along A 33-Year Planting Chronosequence, Clifton Albrecht, Zarek Contreras, Kimberly Wahl-Villarreal, Mitch Sternberg, Bradley O. Christoffersen

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Reforestation in the Lower Rio Grande Valley (LRGV) of Texas began in the 1960s and to date over 6,475 ha of land has been reforested. However, there has been minimal assessment to understand differential species success, compositional trends, and the aboveground C sequestration potential of these developing forests. We coupled quantitative planting information of >50 native woody tree and shrub species with surveys of 5,223 stems of 4,606 individuals in a chronosequence of restored forests ranging in age from 1 to 33 years to estimate species-specific mortality rates, biomass accumulation and recruitment, as well as compositional trends in the herbaceous …

P-Flux: A Phosphorus Budget Dataset Spanning Diverse Agricultural Production Systems In The United States And Canada, M. R. Williams, P. Welikhe, J. Bos, K. King, M. Akland, D. J. Augustine, C. Baffaut, E. G. Beck, A. Bierer, D. D. Bosch, Elizabeth H. Boughton, C. B. Brandani, E. Brooks, Anthony R. Buda, M. Cavigelli, J. Faulkner, G. Feyereisen, A. Fortunato, B. Lee, Jason M. Unrine

Plant and Soil Sciences Faculty Publications

No abstract provided.

Roles Of Phospholipase Dε In Arabidopsis And Soybean Response To Nitrogen Deficiency, Shuaibing Yao

Dissertations

Phospholipase D (PLD) hydrolyzes phospholipids to produce phosphatidic acid (PA) and plays important roles in plant growth, development, and stress response. Of 12 PLDs in Arabidopsis, PLDε is involved in nitrogen response in Arabidopsis and canola, but the mechanism remained elusive. This study was undertaken to investigate how PLDε mediates plant response to nitrogen availability. Nitrogen deficiency induces an increase in PLDε transcript and protein levels and an increased association with intracellular membranes. PLDε interacts with autophagy-related protein 8e (ATG8e), and two of the four predicted ATG8-interacting motifs in PLDε are required for PLDε-ATG8e interactions. PLDε hydrolyzes phosphatidylethanolamine (PE) conjugated …

Shew Family Farms Shares Their Story In Honor Of Athen's Farmers Market 50th Anniversary, Marjorie Shew, Kassidy Rock

Spring 2022 Oral Histories: Athens Farmers Market and The Ridges

Member of the Athens Farmers Market since1984, Marjie Shew of Shew Family Farms, now known as Shew's Grassfed Beef, shares her story. From beginning in upstate New York to living on a commune in West Virginia, to owning an orchard with her husband in Morgan County, Ohio and every step in between.

Examination Of Pre-Emergence Control Of Johnsongrass In Sugarcane Seedlings, Carleton Baucum

LSU Master's Theses

Sugarcane is susceptible to many diseases and insect pests; therefore, to maintain high sugar yield new varieties must be developed. Producing new varieties contributes to the overall crop success through enhanced yield, insect and/or disease resistance, cold tolerance, and ratooning ability. However, unlike conventional sugarcane, which is vegetatively propagated, new sugarcane varieties are produced from true seed. These seedlings are more susceptible to herbicidal injury and weed competition than conventional sugarcane. For sugarcane seedlings to succeed, weeds must be controlled therefore, the most effective herbicide program with regards to seedling safety must be implemented. The objectives of this research were …

Identification And Characterization Of Circular Rnas In Brassica Rapa In Response To Plasmodiophora Brassicae, Huishan Liu, Chinedu Charles Nwafor, Yinglan Piao, Xiaonan Li, Zongxiang Zhan, Zhongyun Piao

Center for Plant Science Innovation: Faculty Publications

Plasmodiophora brassicae is a soil-borne pathogen that attacks the roots of cruciferous plants and causes clubroot disease. CircRNAs are noncoding RNAs, widely existing in plant and animal species. Although knowledge of circRNAs has been updated continuously and rapidly, information about circRNAs in the regulation of clubroot disease resistance is extremely limited in Brassica rapa. Here, Chinese cabbage (BJN 222) containing clubroot resistance genes (CRa) against P. brassicae Pb4 was susceptible to PbE. To investigate the mechanism of cicRNAs responsible for clubroot disease resistance in B. rapa, circRNA-seq was performed with roots of ‘BJN 222’ at 0, 8, and 23 days …

Potensi Hasil Dan Nutrisi Beberapa Genotipe Tanaman Sorgum Lokal Jawa Timur Sebagai Calon Tetua Persilangan, Maftuchah, Dian Puji Rahayu, Agus Zainudin, Sulistyawati, Hendry Sulistiyanto

Jurnal Kultivasi

Tanaman sorgum (Sorghum bicolor (L.) Moench) merupakan tanaman sumber pangan, pakan ternak, dan bahan baku industri yang memiliki potensi untuk dikembangkan di Indonesia. Permasalahan utama dalam komoditas ini adalah masih terbatasnya varietas lokal yang sesuai dengan lingkungan di Indonesia sehingga perlu diupayakan pencarian genotipe lokal sorgum sebagai calon tetua persilangan. Tujuan kegiatan ini adalah untuk mendapatkan informasi potensi daya hasil dan kualitas produk berbagai genotipe sorgum lokal Jawa Timur sebagai calon tetua persilangan untuk menghasilkan varietas unggul. Penelitian ini dilaksanakan di lahan percobaan Desa Purutrejo, Kecamatan Purworejo, Kota Pasuruan-Jawa Timur. Bahan yang digunakan dalam penelitian ini yaitu 9 genotipe tanaman …

Oregon State Rank Assessment For Owyhee Clover (Trifolium Owyheense), Lindsey K. Wise

Institute for Natural Resources Publications

Oregon state conservation status assessment for Owyhee clover (Trifoilum owyheense) using NatureServe methodology, 2022.

Editorial: Accelerating Genetic Gains In Pulses, Aditya Pratap, Shiv Kumar, Patricia L. Polowick, Matthew W. Blair, Michael Baum

Agricultural and Environmental Sciences Faculty Research

No abstract provided.

Trigonella Foenum-Graecum Methanolic Extract On Isolated Smooth Muscles And Acetylcholinesterase Enzyme: An In Vitro And Mechanistic In Silico Investigation, Muhammad Nabeel Ghayur, Mohnad Abdalla, Asaad Khalid, Saeed Ahmad, Anwar Gilani

Department of Biological & Biomedical Sciences

Results: When tested on the baseline of isolated tissues, Tfg.Cr was devoid of any activity (stimulant or relaxant) till 10 mg/ml. This is an interesting finding, keeping in mind that the fenugreek seeds are used to alleviate constipation and diarrhoea. When Tfg.Cr was tried for any potential AChE inhibitory activity, it did show an inhibitory effect in increasing concentrations (47-380 μg/ml). This inhibitory effect was comparable to the effect produced by a standard AChE inhibitor physostigmine. One of the known fenugreek constituents, diosgenin, was also tested, and it also showed an AChE inhibitory effect in a concentration-dependent manner (11-190 …

Fruits Of Nandina Domestica Are (Sometimes) Cyanogenic And (Sometimes) Hazardous To Birds, Scott Zona

Poisonous Plant Research (PPR)

A 12-month survey of cyanogenesis in the fruits and leaves of Nandina domestica (Berberidaceae) revealed that the leaves are strongly cyanogenic throughout the year, as measured by the Feigl-Anger test. Fruits vary in their cyanogenic potential depending on the degree of ripeness and clone. Green fruits are strongly and rapidly cyanogenic, but most ripe fruits are weakly and slowly cyanogenic. Some fruits tested negative for cyanide. Fruits tend to become less cyanogenic the longer they remain on the plant, so birds feeding on older fruits are at a lower risk of poisoning. More than other frugivores, cedar waxwings (Bombycilla …

Considerations For Establishing Silvopastures On Wooded Sites, Brett Chedzoy, Ashley Conway, John Fike, Kate Macfarland

Agroforestry Notes (USDA-NAC)

Like other conservation and production practices, silvopasture management is not the right fit for every site or every land manager. High quality woodlands with high native species diversity are generally not a good starting point for silvopasture establishment. However, silvopasture provides an opportunity for active forest management on other sites that have been neglected or poorly managed with undesirable species composition, invasive species concerns, and other challenges. In some situations, silvopasture management can be used to aid in ecosystem restoration or fuels mitigation. The land manager and others in the silvopasture team should consider natural resource issues highlighted in this …