Digital Commons Network^™

Efficacy Of Antimicrobial Mitigation On Escherichia Coli Cfu And Growth And Development Of Hydroponic Leafy Greens, Nathan J. Eylands

Graduate Theses and Dissertations

The Food and Drug Administration (FDA) have set new standards that apply to agriculturalists producing crops eaten fresh and/or raw by consumers. This new produce safety rule, known as the Food Safety Modernization Act (FSMA), has established science-based standards for all areas of production in agriculture with regards to microbial contamination. Escherichia coli (E. coli) O157:H7 is a particular bacterium of concern under FSMA guidelines. Grower compliance is mandatory and therefore vital to the continuation of any farm. Greenhouse hydroponic growers have shown advantages in efficiency when compared to conventional farming methodology. Those, however, with recirculating hydroponic systems face unique …

Magnolia: Impact Of Interspecific Hybridization On Genetic Variation And Ongoing Breeding Initiatives, James Kevin Parris

All Dissertations

The genus Magnolia comprises over 250 species naturally occurring in Eastern North America, Central America, South America, islands of the Gulf of Mexico, and Eastern Asia. A long history of cultivation and breeding going back to the early nineteenth century reveals a common trend of reproductive compatibility throughout this group of basal angiosperms. Interspecific hybridization has led to plethora of ornamental cultivars that have proven adaptable to natural and cultivated habitats beyond the range of each species. Understanding of taxonomic relationships between species has evolved as observations of morphological characteristics and genetic analyses have been more thoroughly investigated. The objectives …

Responses Of Ornamental Grass And Grass-Like Plants To Saline Water Irrigation, Youping Sun, Alyssa Lanae Palmer

Plants, Soils, and Climate Faculty Publications

Ornamental grasses are popular in urban landscapes in Utah and the Intermountain West United States, one of the driest and fastest growing regions in the United States. This experiment evaluated the responses of five ornamental grass species [blue grama (Bouteloua gracilis), indian sea oats (Chasmanthium latifolium), ‘Blue Dune’ sand ryegrass (Leymus arenarius), pink muhly grass (Muhlenbergia capillaris), ‘Foxtrot’ fountain grass (Pennisetum alopecuroides)] and two ornamental grasslike species [fox sedge (Carex vulpinoidea), common rush (Juncus effusus)] to saline irrigation water in a greenhouse. Plants were irrigated weekly …

Weed Control And Management For Vegetable Soybeans In Arkansas, Seth Bernard Abugho

Graduate Theses and Dissertations

Vegetable soybean [Glycine max (L.) Merr.], known as edamame, needs weed management tools. Releasing locally adapted edamame soybean varieties and registering herbicides are necessary for successful production and expanding the edamame industry. This research aimed to 1) identify herbicides labeled for grain soybean for potential use on edamame; 2) evaluate differential tolerance of edamame soybean varieties to selected grain soybean herbicides; and 3) identify a feasible edamame-based crop rotation system. For objective 1, 26 herbicide treatments were tested on AVS-4002 edamame including preplant (PPL), preemergence (PRE) and postemergence (POST) herbicides labeled for grain soybean. Preplant herbicides caused 9 to 28% …

Synthesis Of Dicamba Glucosides For The Study Of Environmental Dicamba Drift Effects On Soybeans, Holly Wallace

Graduate Theses and Dissertations

The most popular herbicide used for weed control has been glyphosate for many years in the Midwestern United States. Plants have begun to develop a resistance to glyphosate due to over use of the herbicide. This herbicide resistance has pushed farmers to turn to alternative herbicides such as dicamba and 2,4-D. Recently agrochemical companies have developed genetically modified crops that are resistant to herbicides such as dicamba. These modified crops allow farmers to spray their fields with dicamba without fear of crop damage. Farmers of non-genetically modified crops, however, suffer damage and loss of yield from herbicide drift effects of …

Evaluation And Characterization Of Fitness Costs In Multiple Herbicide Resistant Echinochloa In Arkansas, Teal Marie Penka

Graduate Theses and Dissertations

Echinochloa spp. are major weed problems for rice (Oryza sativa L.) on a global scale. In the southern rice belt of the U.S.A., Echinochloa colona (L.) Link (junglerice) and E. crus-galli (L.) P. Beauv (barnyardgrass) are the most troublesome weeds. These species are morphologically diverse, and its high ploidy level augurs high genetic diversity, which favors high adaptability to stress, including herbicide selection pressure. The objectives of these studies were to 1) isolate resistant (R) and sensitive (S) biotypes from eight accessions of E. colona with different resistance profiles; 2) determine the resistance levels of selected R and S biotypes …

Influence Of Loss Of Function Of The Fatty Acid Desaturase 7 Gene On Photosynthetic Activity And Foliar Redox Status, Janithri Savindya Wickramanayake

Graduate Theses and Dissertations

Fatty Acid Desaturase7 (FAD7) is a chloroplast-localized enzyme that converts 16 and 18 carbon dienoic fatty acids to trienoic fatty acids. The suppressor of prosystemin-mediated response2 (spr2) mutant in tomato (Solanum lycopersicum) and the fad7-1 mutant in Arabidopsis (Arabidopsis thaliana) result in the loss of function of FAD7, which alter the fatty acid profiles of chloroplast membranes and enhance resistance against aphids. This research contributes toward the long-term goal of identifying factors that determine aphid resistance in FAD7 mutants. Previous data suggested constitutive differences between spr2 and WT including increased expression of genes associated with photosynthesis and differences in redox …

Bryophyte Assemblages On American Hornbeam (Carpinus Caroliniana) And The Surrounding Arboreal Communities Within The Forest Of East Texas, Cassey Edwards

Electronic Theses and Dissertations

The bryophytes, the non-vascular plants, include the mosses (Bryophyta with approximately 13,000 species), the liverworts (Marchantiophyta with approximately 5,000 species), and the hornworts (Anthocerotophyta with approximately 150 species). Initial observations indicated that the midstory tree Carpinus caroliniana Walter (American hornbeam) has a bryophyte composition with an unusually high diversity of leafy liverworts. Voucher samples were taken from the four intercardinal directions (Northeast, Northwest, Southwest, and Southeast) from six Carpinus trees and their nearest neighbor that was neither Pinus nor another Carpinus at each of six sites across East Texas. Percent coverage, species richness, Shannon’s diversity and Pielou’s evenness were computed. …

Interactions Between Biochar And Compost In Organic Winter Wheat Production And Soil Quality Under Dryland Conditions, Phearen Kit Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Organic wheat grown under dryland conditions encounters challenges such as limited nutrients and water. Maintaining organic wheat production requires solutions to these problems in order to retain economic sustainability for the farmers.

Research on biochar and compost have been conducted globally. Despite well known benefits of compost on soil and crop production, few organic farmers apply compost to their fields. Research on biochar is still new. Biochar is charcoal created from pyrolyzing agricultural material under conditions of low oxygen and high heat. Many studies claim that biochar is a valuable soil amendment for improving organic production and reducing environmental pollution …

A Simple Metabolic Switch May Activate Apomixis In Arabidopsis Thaliana, David Alan Sherwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Apomixis, asexual or clonal seed production in plants, can decrease the cost of producing hybrid seed and enable currently open pollinated crops to be converted to more vigorous and higher yielding hybrids that can reproduce themselves through their own seed. Sexual reproduction may be triggered by a programmed stress signaling event that occurs in both the meiocyte, just prior to meiosis, and later in the egg just prior to embryo sac maturation. The prevention of stress signaling and the activation of a pro-growth signal prior to meiosis triggered apomeiosis, the first half of apomixis. The same approach was used prior …

Localization Of Sip470, A Plant Lipid Transfer Protein In Nicotiana Tabacum, Shantaya Andrews

Electronic Theses and Dissertations

SABP2-interacting protein 470 (SIP470), a non-specific lipid transfer protein (nsLTP), was discovered in a yeast two-hybrid screening using SABP2 as bait and tobacco leaf proteins as prey. SABP2 is an important enzyme in systemic acquired resistance that converts salicylic acid to methyl salicylate. Localization studies are an important aspect to understanding the biological function of proteins. nsLTPs are generally considered apoplastic proteins and has been localized intracellularly and extracellularly. Transient expression shows highest expression of SIP470-eGFP at 2 days post infiltration into Nicotiana benthamiana. Confocal microscopy showed localization near the periphery of the cell. Subcellular localization using differential centrifugation showed …

Linkage Mapping For Soybean (Glycine Max) Flood Tolerance, Wade Stiles Hummer

Graduate Theses and Dissertations

Flood tolerance in soybean (Glycine max) is not a well-characterized trait, yet flooding damage is second only to drought stress in terms of yield reduction. The objectives of this study were to determine genetic variation for flooding tolerance in two populations of soybean recombinant inbred lines (RILs) and to identify and confirm flood tolerant QTL. Population A (WHA) consisted of 111 RILs derived from the cross 5002T by 91210-350 and Population B (WHB) consisted of 79 RILs from the cross RA-452 by Osage. Experiments were conducted at the Rice Research and Extension Center (RREC) near Stuttgart, AR in 2015 and …

Impact Of Roadside Maintenance Practices On Larinus Minutus (Gyllenhal), A Biological Control Agent Of Spotted Knapweed, Mary Elizabeth Ferguson

Graduate Theses and Dissertations

Spotted knapweed, Centaurea stoebe, is an invasive weed found throughout much of the United States. Spotted knapweed is a rangeland weed where it was originally introduced into western North America in the 1880s.Where spotted knapweed spread to the southeastern U.S., it is found mostly along roadsides. It has been the focus of a biological control program beginning in the 1960s, with 12 insects established, with the final introductions occurring in the 1990s. After the success observed in the western U.S. and Canada with one of these insects, Larinus minutus, this weevil was established in northwestern Arkansas. It is too early …

Where Are All Of Arkansas' Chinquapins? An Ecological Assessment Of Castanea Throughout The State, Logan Pierce Estes

Graduate Theses and Dissertations

Around the turn of the twentieth-century, the chestnut blight fungus (Cryphonectria parasitica) was accidentally introduced into North America. This strong pathogen, which specializes on trees of the genus Castanea, spread rapidly and within half a century had nearly extirpated North America’s Castanea natives from their ranges. During this catastrophe, the American chestnut (Castanea dentata) garnered much of the scientific attention, pushing the other Castanea natives – the chinquapins – to the wayside. More than a century following the spread of the blight, little research into the ecology of North America’s chinquapins had been performed, leaving these trees significantly underrepresented. The …

Evaluation Of Rice Stink Bug, Oebalus Pugnax (F.), Damage And Monitoring Techniques In Rice, Oryza Sativa L., And Grain Sorghum, Sorghum Bicolor (L.), Aaron Joseph Cato

Graduate Theses and Dissertations

Rice stink bug, Oebalus pugnax (F.), is a serious pest of headed rice, Oryza sativa L. and an occasional pest of heading grain sorghum in the Mid-south. Work from this dissertation focuses on resolving gaps in and knowledge of rice stink bug sampling and management, and attempts to create a basis for rice stink bug damage assessment in future studies.

Field experiments were conducted from 2016-2018 to asses variation in sweep net sampling by observing producers, researchers, extension personnel, consultants and their workers. Large levels of variation were found in sweep lengths between observed sweepers and reliability of smaller sweep …

Evaluation Of Soybean Maturity Group And Planting Date In A Soybean-Rice Rotation On Overall Crop Productivity, Carrie Ortel

Graduate Theses and Dissertations

Little is known about the effects of soybean (Glycine max L.) management techniques on soil-nitrogen (N) credit development and its impact on the subsequent rice (Oryza sativa L.) crop’s success. This study was conducted to determine how soybean maturity group (MG) and planting date effect overall soybean productivity and its influence on the following rice crop. Various soybean planting dates (optimum and late) and MGs (3.5, 4.7, 5.4, and 5.6) were grown and followed in rotation with a rice crop. Six rates of pre-flood fertilizer-N (0, 44, 89, 134, 179, 224 kg N ha-1) were applied to the rice crop. …

Physiological Characterization Of The Soynam Parental Lines Under Field Conditions, Akshita Mishra

Graduate Theses and Dissertations

The narrow genetic pool of soybean (Glycine max L. Merr.) in North America can limit its future yield gains. Among the worldwide germplasm collection of 45,000 unique landraces, only 80 contribute 99% to the collective parentage of North American soybean cultivars. Among these 80 landraces, just 17 contribute to 86% of the collective parentage of the modern cultivars. The Soybean Nested Association Mapping population (SoyNAM) was therefore developed with the objective of diversifying the soybean gene pool. Forty diverse soybean genotypes from maturity groups (MG) 1 through 5 were crossed with a common MG 3 parent to develop 40 recombinant …

Vegetation Characteristics And Bird Communities Associated With Singing Painted Buntings In Northwest Arkansas, Lauren Kristina Thead

Graduate Theses and Dissertations

It has been shown that bird communities are affected by the species composition and physical structure of plant communities. Within avian communities, the bird species that are the most localized in distribution tend to be the most affected by habitat changes. My research analyzed plant and bird communities found with the Painted Bunting (Passerina ciris Linnaeus), a locally common but declining species throughout much of its range. First, I describe vegetation characteristics associated with singing male Painted Buntings in northwest Arkansas. I categorized field sites with singing male Painted Buntings as either managed for wildlife or unmanaged, based on land-use …

Ripeness Attributes Of Arkansas-Grown Peaches And Nectarines At Harvest And During Postharvest Storage, Mary Siebenmorgen

Food Science Undergraduate Honors Theses

Evaluating ripeness attributes of peaches and nectarines helps determine feasibility for commercial markets. Five cultivars (Amoore Sweet, Bowden, Bradley, Effie, and Souvenirs) and five breeding selections (A-663 CN, A-794 CN, A-811 CN, A-819, and A-885) were hand harvested in 2017 from the University of Arkansas System Division of Agriculture’s Fruit Research Station in Clarksville, AR. The tree-ripened fruit was evaluated at harvest (day 0), and commercially-ripened fruit (ripened during storage) was evaluated at 0, 7 and 14 d storage at 4° C. The attributes of tree and commercially-ripened fruit varied at harvest and included chlorophyll (0.04-0.86 abs), weight (132-264 g), …

Arkansas Corn And Grain Sorghum Performance Tests 2018, R. D. Bond, J. A. Still, J. F. Carlin

Arkansas Agricultural Experiment Station Research Series

Corn and grain sorghum performance tests are conducted each year in Arkansas by the University of Arkansas System Division of Agriculture. The tests provide information to companies marketing seed within the state, and aid the Arkansas Cooperative Extension Service in formulating recommendations for producers.

Systems To Attract And Feed Pollinators In Warm-Season Lawns, Michelle Wisdom

Graduate Theses and Dissertations

Pollinating insects are responsible for the production of many agricultural crops and they require floral resources to fulfill their life-cycle. Ideally, pollinating insects will encounter a diversity of floral resources across their entire season of activity, and those floral resources can include both herbaceous and woody plant species. Managed turfgrass areas have been identified as potential locations for creating pollinator-friendly habitats. In the transition zone, where both warm- and cool-season turfgrass species are present, the persistence of herbaceous plants in warm-season turfgrasses such as bermudagrass (Cynodon spp.) and buffalograss (Buchloe dactyloides), may be affected not only by the competitive nature …

Preparing An Effective Poster Presentation, Christopher N. Jacques

The Prairie Naturalist

Greetings GPNSS members! By the time you read this editorial, many of have been experiencing the fury unleashed by ‘Old Man Winter’ and may find yourself counting the days until warmer spring temperatures return once again to the Great Plains. Until then, just a couple more months of bitter cold temperatures, strong winds, and blowing and drifting snow. But not to worry, winter also provides the cold weather enthusiasts among us a chance to enjoy a range of outdoor recreational opportunities, a chance to reflect on the previous year in review, exciting professional and personal opportunities ushered in by the …

Red-Bellied Snake (Storeria Occipitomaculata) Copulation In South Dakota, Drew R. Davis

The Prairie Naturalist

Storeria occipitomaculata is a small, terrestrial species of snake that occurs across much of eastern North America (Ernst and Barbour 1989, Ernst 2002, Ernst and Ernst 2003). Due to this widespread distribution, S. occipitomaculata faces varied climates that likely result in regional differences in reproductive phenology. Much of what is known about the reproductive ecology of S. occipitomaculata has been documented from the southeastern portion of its range in North America (South Carolina: Semlitsch and Moran 1984, North Carolina: Willson and Dorcas 2004), though Blanchard (1937) studied a population from northern Michigan. The exact reproductive timing in this species has …

New Breeding Record And Location For Wilson’S Phalarope (Phalaropus Tricolor) In The Nebraska Great Plains, Usa, Madison O. Sutton, Nico Arcilla

The Prairie Naturalist

Wilson’s phalarope (Phalaropus tricolor; Scolopacidae) is a migratory shorebird that relies on interior wetlands for foraging and breeding (Colwell and Jehl 1994, van Gils et al. 2018). Its global population status is unclear (Colwell and Jehl 1994, Lesterhuis and Clay 2010), and is variously listed as declining (Morrison et al. 2006, van Gils et al. 2018), increasing (Andres 2009, BirdLife International 2018), and exhibiting a long-term decline but recent stability (Sauer et al. 2011, Andres et al. 2012). Its global population estimate of 1.5 million birds has not been updated for 30 years, since 1988 (Colwell and Jehl 1994, Lesterhuis …

Edges And Rushes Of Minnesota: The Completeguidetospeciesidentification. Welby R. Smith; Photography By Richard Haug., Edward S. Dekeyser

The Prairie Naturalist

Even the most seasoned individual with a plant identification background can relate to the difficulty of identifying sedges and rushes to the species level. Historically, one has had to rely on dichotomous keys to identify a sedge or rush species in the field. After hours of frustration, a person ends up collecting the plant and, if lucky, bringing the collection back to a herbarium where it can be compared to known specimens. I have been collecting and identifying sedge and rush species for over 25 years, and author Welby Smith along with photographer Richard Haug have published what I believe …

Metabolic Gas Emissions From Prairie Soil Containing Foraging Termites, Charles E. Konemann, B.M. Kard, Tom A. Royer, Mark E. Payton

The Prairie Naturalist

Differences in subterranean termite metabolic gas emissions are readily observed in laboratory experiments. However, in natural field ecosystems a primary difficulty in measuring subterranean termite gases is non-homogeneous distribution of foraging termites in soil. Our field experiment was designed to aggregate foragers of the 'eastern subterranean termite', Reticulitermes flavipes Kollar (EST), in one of four flux chamber configurations placed on a tallgrass prairie throughout 2014 and 2015. We used differently configured flux chambers to measure metabolic gas emissions from soil with or without foraging termites on The Joseph H. Williams Tallgrass Prairie Preserve (TGPP) in north-central Oklahoma. Foraging termitesaggregated in …

Notes: Two-Headed White-Tailed Deer Fetus, William F. Jensen, Daniel M. Grove, Ryan J. Herigstad, William J. Haase

The Prairie Naturalist

On 6 April 2018 a female white-tailed deer (Odocoileus virginianus dakotensis) was hit and killed by a vehicle along HWY 1806 in rural Morton County, North Dakota, USA (N46o 38.617; W100o 42.901). Based upon dental eruption and wear (Severinghaus 1949), the female was estimated to be a >4.5 years-of-age. A male fetus with parapagus diprosopus (i.e., shared face) apparently was expelled from the adult female, and a domestic canine (Canis lupus familiaris) carried the fetus to a private residence. The resident contacted the North Dakota Game and Fish Department (NDGFD) to turn in the fetus. On 10 April 2018, NDGFD …

Comparison Of Northern Flying And Red Squirrel Phylogenies With Focus On The Insular United States, Alyssa M. Kiesow, Hugh B. Britten

The Prairie Naturalist

Northern flying squirrel (Glaucomys sabrinus) and red squirrel (Tamiasciurus hudsonicus) populations are endemic to northern North America, including the Black Hills. The Black Hills populations are considered disjunct from other populations within their range. We examined insular populations to determine whether arboreal squirrels in the Black Hills each represent a unique population. We trapped and collected ear samples from northern flying and red squirrels in the Black Hills and in areas of Montana, Wyoming, Idaho, Utah, Minnesota, and Wisconsin to infer population phylogenies with special consideration of the Black Hills population. Microsatellite loci and two mtDNA sequences were used for …

Evaluation Of Goji Berry (Lycium Barbarum L.) Cultivars And Air Root Pruning For Edible Greens Production In The Midwest, Jesse Lee Carroll

MSU Graduate Theses

Goji berry plants (Lycium barbarum L.) are grown across the globe for their berries and the health benefits that come from eating those berries. However, in Ningxia, China, Goji berry plants are also grown as a source of edible greens. In order to harvest the young green shoots, the plants are subjected to intense pruning and kept as a small, low-growing shrub. There is little information on this method of Goji berry management and greens production in the United States. The purpose of this research is to determine if Goji berry cultivars grown for berry production in the United …

Effects Of Irrigation On Forage Growth Rates On Rotational Grazing Dairies, Zachary Davis

MSU Graduate Theses

The amount and timing of rainfall in Missouri can be very irregular. This causes issues for producers of agronomic products in the state who rely on forages for income. The most sensible approach to the problem is the use of irrigation. But there is little useful information to reference when implementing this management decision. By studying three different styles of irrigation (center pivot, spider, and k-line) on 4 species of forages native to Missouri (alfalfa, crabgrass, perennial ryegrass, and tall fescue/clover), this study provides valuable insight as to the cost and benefit of irrigation. The main goal is to produce …