Plant Biology Commons^™

A Plant Trait-Based Approach To Evaluate The Ability Of Native C3 And C4 Grasses To Restore Functionality To A Remnant Bluegrass Savanna-Woodland In Kentucky, Usa., Jann E. Fry

Theses and Dissertations--Biology

Temperate Midwestern oak savannas are considered imperiled ecosystems with < 1 % remaining since the time of European settlement and are identified as critical areas for preservation. Restoration of Midwestern oak savannas is challenging due to the lack of accurate historical data, few intact remnants remaining to study, and lack of restoration ecology studies. A plant trait-based approach was used to evaluate the ability of six C₃ and three C₄ native bunchgrasses to restore functionality to a remnant savanna–woodland of the Bluegrass Region of Kentucky. The response and effect framework was used to assess the response of the nine native grasses according to the habitat filters of interannual precipitation, inter- vs. intra-specific competition, and simulated grazing. The effect traits associated with plant-soil nitrogen and carbon cycling were also assessed. The response traits of interannual competition and inter- vs. intra-specific competition along with the effect traits plant-soil nitrogen and carbon cycling were measured in a monoculture experiment …

Dynamics Of Small Rna Profiles Of Virus And Host Origin In Wheat Cultivars Synergistically Infected By Wheat Streak Mosaic Virus And Triticum Mosaic Virus: Virus Infection Caused A Drastic Shift In The Endogenous Small Rna Profile, Satyanarayana Tatineni, Jean-Jack M. Riethoven, Robert A. Graybosch, Roy French, Amitava Mitra

Department of Plant Pathology: Faculty Publications

Co-infection of wheat (Triticum aestivum L.) by Wheat streak mosaic virus (WSMV, a Tritimovirus) and Triticum mosaic virus (TriMV, a Poacevirus) of the family Potyviridae causes synergistic interaction. In this study, the effects of the synergistic interaction between WSMV and TriMV on endogenous and virus-derived small interfering RNAs (vsiRNAs) were examined in susceptible (‘Arapahoe’) and temperature-sensitive resistant (‘Mace’) wheat cultivars at 18 degrees C and 27 degrees C. Single and double infections in wheat caused a shift in the profile of endogenous small RNAs from 24 nt being the most predominant in healthy plants to 21 nt …

Quantification Of Yield Loss Caused By Triticum Mosaic Virus And Wheat Streak Mosaic Virus In Winter Wheat Under Field Conditions, E. Byamukama, S. N. Wegulo, S. Tatineni, G. L. Hein, R. A. Graybosch, P. Stephen Baenziger, R. French

Department of Plant Pathology: Faculty Publications

Triticum mosaic virus (TriMV) and Wheat streak mosaic virus (WSMV) infect winter wheat (Triticum aestivum) in the Great Plains region of the United States. The two viruses are transmitted by wheat curl mites (Aceria tosichella), which also transmit High Plains virus. In a field study conducted in 2011 and 2012, winter wheat cultivars Millennium (WSMV-susceptible) and Mace (WSMV-resistant) were mechanically inoculated with TriMV, WSMV, TriMV+WSMV, or sterile water at the two-leaf growth stage. Chlorophyll meter (soil plant analysis development [SPAD]) readings, area under the SPAD progress curve (AUSPC), grain yield (=yield), yield components (spikes/m², …

Studies On Sensitivity Reduction In Solo And Mixture Treatments And Fungicide-Induced Mutagenesis In Monilinia Fructicola, Guido Schnabel, F. Chen, Sydney E. Everhart, W. C. Bridges, X. Liu

Department of Plant Pathology: Faculty Publications

Three fungicide-sensitive Monilinia fructicola isolates were exposed in weekly transfers of mycelia to a dose gradient of a DMI and a QoI fungicide (azoxystrobin) in solo or mixture treatments and fungicide sensitivity as well as genetic changes were assessed. Isolates showed a faster reduction in sensitivity (higher resistance factors) to azoxystrobin than to SYP-Z048; this process was slower in the mixture treatment. The decrease of fungicide sensitivity was not a heritable trait. Genomic mutagenesis at 8 of 15 microsatellite loci was evidenced in one of three isolates tested after exposure to azoxystrobin. These non-coding regions of the genome either showed …

Methods For Using Cryptococcus Flavescens Strains For Biological Control Of Fusarium Head Blight, Brian B. Mcspadden Gardener, Pierce Anderson Paul, Michael J. Boehm, Xiaoqing Rong, David Schisler

Department of Plant Pathology: Faculty Publications

Disclosed are methods of identifying subspecies of Cryptococcus flavescens and methods of treating or suppressing Fusarium head blight with the different Cryptococcus flavescens species. In particular, two genotypes, Genotypes A and B, were identified using the disclosed real time PCR technique. The following Cryptococcus flavescens strains were identified as being either Genotype A or B and as being able to suppress Fusarium head blight: NRRLY-7373, YB-601, YB-602, Y-7377, Y-7372, Y-7375, Y-7374, Y-7376, YB-328, Y-7379, and YB-744.

Smut Diseases Of Corn, Tamra Jackson-Ziems

Department of Plant Pathology: Faculty Publications

This NebGuide describes the two smut diseases of corn in Nebraska, common smut and head smut, including their symptoms, life cycle, and management.

Two smut diseases of corn occur in Nebraska (Figure 1). Despite their similar appearance, their disease cycles are very different, as are their yield loss potential and management strategies (Table 1).

Common Stalk Rot Diseases Of Corn, Tamra A. Jackson-Ziems, Jennifer M. Rees, Robert M. Harveson

Department of Plant Pathology: Faculty Publications

Extension Circular 1898 (EC1898)

Stalk rot diseases of corn are common, occurring in every field to some extent. Each year stalk rot diseases cause about 5 percent yield loss. Under some conditions, losses can exceed 10–20 percent, and in isolated areas losses have been as high as 100 percent. Stalk rot diseases reduce yield both directly and indirectly. Plants with prematurely rotted stalks produce lightweight, poorly filled ears because of the plant’s limited access to carbohydrates during grain fill. Infected stalks are converted from sturdy, solid rods to hollow tubes as the stalk pith pulls away from the outer rind, …

Disease Profiles: Nematodes Of Nebraska Field Crops, Tamra A. Jackson-Ziems, Loren J. Giesler, Robert M. Harveson, Kevin A. Korus, Stephen N. Wegulo

Department of Plant Pathology: Faculty Publications

Extension Circular 1908 (EC1908).

Many species of plant parasitic nematodes affect Nebraska field crops. Some of the more common and/or damaging nematodes are described here. The extent of crop injury depends on the species present, their abundance, and other crop stresses. Diagnosis of nematode injury is difficult because most plant parasitic nematodes can’t be seen with the naked eye and the type and severity of symptoms can vary widely. Most nematodes cause general symptoms that are not diagnostic and may mimic symptoms caused by other biotic or abiotic problems, such as herbicide damage, nutrient imbalances, water stress, and insect feeding. …

Plant Defense Suppression Is Mediated By A Fungal Sirtuin During Rice Infection By Magnaporthe Oryzae, Jessie Fernandez, Margarita Marroquin-Guzman, Renu Nandakumar, Sara Shijo, Kathryn M. Cornwell, Gang Li, Richard Wilson

Department of Plant Pathology: Faculty Publications

Crop destruction by the hemibiotrophic rice pathogen Magnaporthe oryzae requires plant defense suppression to facilitate extensive biotrophic growth in host cells before the onset of necrosis. How this is achieved at the genetic level is not well understood. Here, we report that a M. oryzae sirtuin, MoSir2, plays an essential role in rice defense suppression and colonization by controlling superoxide dismutase (SOD) gene expression. Loss of MoSir2 function in Δsir2 strains did not affect appressorial function, but biotrophic growth in rice cells was attenuated. Compared to wild type, Δsir2 strains failed to neutralize plant-derived reactive oxygen species (ROS) …

A Global Database Of Soil Nematode Abundance And Functional Group Composition, Johan Hoogen, Peter Mullen, 72 Other Scholars

Department of Plant Pathology: Faculty Publications

As the most abundant animals on earth, nematodes are a dominant component of the soil community. They play critical roles in regulating biogeochemical cycles and vegetation dynamics within and across landscapes and are an indicator of soil biological activity. Here, we present a comprehensive global dataset of soil nematode abundance and functional group composition. This dataset includes 6,825 georeferenced soil samples from all continents and biomes. For geospatial mapping purposes these samples are aggregated into 1,933 unique 1-km pixels, each of which is linked to 73 global environmental covariate data layers. Altogether, this dataset can help to gain insight into …

A Genome-Wide Association Study Of Seed Protein And Oil Content In Soybean, Eun-Young Hwang, Qijian Song, Gaofeng Jia, James E. Specht, David L. Hyten, Jose Costa, Perry B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Background: Association analysis is an alternative to conventional family-based methods to detect the location of gene(s) or quantitative trait loci (QTL) and provides relatively high resolution in terms of defining the genome position of a gene or QTL. Seed protein and oil concentration are quantitative traits which are determined by the interaction among many genes with small to moderate genetic effects and their interaction with the environment. In this study, a genome-wide association study (GWAS) was performed to identify quantitative trait loci (QTL) controlling seed protein and oil concentration in 298 soybean germplasm accessions exhibiting a wide range of …

Comparison Of Winter Strawberry Production In A Commercial Heated High Tunnel Versus A University Greenhouse, Ellen T. Paparozzi, Ryan Pekarek, George E. Meyer, Stacy A. Adams, M. Elizabeth Conley, David P. Lambe, Paul Read, Erin E. Blankenship

Department of Agronomy and Horticulture: Faculty Publications

For the past 4 years, the University of Nebraska strawberry team has worked to develop low cost, sustainable methods for farmers and growers to produce strawberries in a double polyethylene greenhouse during the winter. This past year, this growing system was adapted to become a commercial grower’s heated high tunnel for the winter/spring of 2013-14. The idea was to scale up to a farm-size demonstration and compare it to the university greenhouse production system with a goal to expand marketing opportunities for strawberries into the winter season.

Greenhouse Gas Emissions From Soil Treated With Dung Pats, Kenneth Evans, Ana Wingeyer, Martha Mamo, Walter H. Schacht, Pamela Sutton, Kent M. Eskridge

Department of Agronomy and Horticulture: Faculty Publications

No abstract provided.

Fate Of C And N From Dung Pats Into Soil, Kenneth Evans, Ana Wingeyer, Martha Mamo, Pamela Sutton, Jeff Bradshaw, Kent M. Eskridge, Matt Judkins, Jenna Beckmann, Erin Hatch

Department of Agronomy and Horticulture: Faculty Publications

No abstract provided.

Quantitative Trait Loci (Qtl) That Underlie Scn Resistance In Soybean [Glycine Max (L.) Merr.] Pi438489b By ‘Hamilton’ Recombinant Inbred Line (Ril) Population, Kassem My Abdelmajid, Laura Ramos, D. L. Hyten, Jason Bond, Abdelhafid Bendahmane, Prakash R. Arelli, Victor N. Njiti, Silvia Cianzio, Stella K. Kantartzi, Khalid Meksem

Department of Agronomy and Horticulture: Faculty Publications

Soybean cyst nematode caused by Heterodera glycines Ichinohe is the most devastating pest in soybean [Glycine max (L.) Merr.]. Resistance to SCN is complex, polygenic, race and cultivar specific, and it is controlled by several quantitative trait loci (QTL). Our objective was to identify and map QTL for SCN resistance to races 3 (HG Type 0) and 5 (HG Type 2.5.7) using a high density SNP-based genetic linkage map based on the PI438489B by ‘Hamilton’ (PIxH, n=50) recombinant inbred line population. The PI438489B by Hamilton map contained 648 SNPs distributed on 31 LGs with coverage of 1,524.7 cM and …

Phytophthora Root Rot Resistance In Soybean E00003, Zhongnan Zhang, Jianjun Hao, Jiazheng Yuan, Qijian Song, D. L. Hyten, P. B. Cregan, Guorong Zhang, Cuihua Gu, Ming Li, Dechun Wang

Department of Agronomy and Horticulture: Faculty Publications

Phytophthora root rot (PRR) is a devastating disease in soybean [Glycine max (L.) Merr.] production. Michigan elite soybean E00003 is resistant to Phytophthora sojae and has been used as a resistance source in breeding. Genetic control of PRR resistance in this source is unknown. To facilitate marker-assisted selection (MAS), the PRR resistance loci in E00003 and their map locations need to be determined. In this study, a genetic mapping approach was used to identify major PRR -resistant loci in E00003. The mapping population consists of 240 F₄–derived lines developed by crossing E00003 with the P. sojae susceptible …

Mapping The Low Palmitate Fap1 Mutation And Validation Of Its Effects In Soybean Oil And Agronomic Traits In Three Soybean Populations, Andrea J. Cardinal, Rebecca Whetten, Sanbao Wang, Jérôme Auclair, D. L. Hyten, P. B. Cregan, Eleni Bachlava, Jason Gillman, Martha Ramirez, Ralph Dewey, Greg Upchurch, Lilian Miranda, Joesph W. Burton

Department of Agronomy and Horticulture: Faculty Publications

Soybean oil with reduced palmitic acid content is desirable to reduce the health risks associated with consumption of this fatty acid. The objectives of this study were: to identify the genomic location of the reduced palmitate fap1 mutation, determine its molecular basis, estimate the amount of phenotypic variation in fatty acid composition explained by this locus, determine if there are epistatic interactions between the fap1 and fap_nc loci and, determine if the fap1 mutation has pleiotropic effects on seed yield, oil and protein content in three soybean populations. This study detected two major QTL for 16:0 content located in …

Identification Of New Qtls For Seed Mineral, Cysteine, And Methionine Concentrations In Soybean [Glycine Max (L.) Merr.], Raghuprakash Kastoori Ramamurthy, Joseph Jedlicka, George L. Graef, Brian M. Waters

Department of Agronomy and Horticulture: Faculty Publications

Increased concentrations of important nutrients in edible parts of plants could result in biofortified foods. Soybean [Glycine max (L.) Merr.] is a major legume crop and an important source of certain nutrients, including protein and minerals, in human and animal diets. Understanding the underlying genetic basis of seed composition is crucial to improving seed nutrient composition. In this study we used three soybean recombinant inbred line mapping populations derived from the crosses Williams 82 × DSR-173, Williams 82 × NKS19-90 and Williams 82 × Vinton 81, and constructed a joint linkage map from these populations. Forty quantitative trait loci (QTLs) …

Development Of Scar Markers And Up-Pcr Cross-Hybridization Method For Specific Detection Of Four Major Subgroups Of Rhizoctonia From Infected Turfgrasses, Bimal S. Amaradasa, Dilip Lakshman, Brandon J. Horvath, Keenan Amundsen

Department of Agronomy and Horticulture: Faculty Publications

A rapid identification assay for Waitea circinata (anamorph: Rhizoctonia spp.) varieties zeae and circinata causing patch diseases on turfgrasses was developed based on the universally primed PCR (UPPCR) products cross-blot hybridization. Tester isolates belonging to the two varieties of W. circinata were amplified with a single UP primer L21, which generated multiple DNA fragments for each variety. Probes were prepared with UP-PCR products of each tester isolate by labeling with digoxigenin. Fieldcollected W. circinata isolates and representative isolates of different R. solani anastomosis groups (AG) and AG subgroups were amplified with L21, immobilized on nylon membrane and cross hybridized with …

Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart Birrell, David Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt

Department of Agronomy and Horticulture: Faculty Publications

Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus × giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced …

Eqtl Networks Reveal Complex Genetic Architecture In The Immature Soybean Seed, Yung-Tsi Bolon, D. Hyten, James H. Orf, Carroll P. Vance, Gary J. Muehlbauer

Department of Agronomy and Horticulture: Faculty Publications

The complex network of regulatory factors and interactions involved in transcriptional regulation within the seed is not well understood. To evaluate gene expression regulation in the immature seed, we utilized a genetical genomics approach on a soybean [Glycine max (L.) Merr.] recombinant inbred line (RIL) population and produced a genome-wide expression quantitative trait loci (eQTL) dataset. The validity of the dataset was confirmed by mapping the eQTL hotspot for flavonoid biosynthesis-related genes to a region containing repeats of chalcone synthase (CHS) genes known to correspond to the soybean inhibitor locus that regulates seed color. We then identified eQTL for …

Corn (Zea Mays) Emergence And Early Growth As Influenced By Tansymustard (Descurainia Pinnata) Residue, Rodrigo Werle, Leonardo L. Perez, Lowell D. Sandell, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Farmers have observed reduced early growth of corn in the presence of tansymustard [Descurainia pinnata (Walt.) Britt.], a winter annual weed of the Brassicaceae family. A greenhouse study was conducted to evaluate the effect of tansymustard on corn (Zea mays L.) emergence and early growth. Treatments included corn growing in pots with only tansymustard root residue, with only tansymustard shoot residue, and with whole tansymustard plant residue (roots plus shoots); tansymustard plants treated with glyphosate 2 days after planting (DAP) corn seeds; and a control (no tansymustard residue). Corn emergence was recorded and biomass measured after 4 weeks of …

Phenotypic Variation In Native North American And Invasive Chinese Populations Of Plantago Virginica, Teresa E. Popp

College of Graduate Studies: Theses & Dissertations

Alien plant species can cause significant economic and biological destruction by invading new environments and outcompeting native species. Through experimental research, the mechanisms by which these species invade can be better understood and applied to their management. Plantago virginica is a perennial herb, native to North America that has recently invaded China. It has been known to reduce crop growth and harbor diseases in the introduced range. A common garden study was conducted at the Georgia Southern University greenhouse, comparing twenty populations of P. virginica from both the native North American and invasive Chinese ranges. I examined if there were …

Evaluation Of Soilless Media Sensors For Managing Winter-Time Greenhouse Strawberry Production Using A Capmat System, George E. Meyer, Ellen T. Paparozzi, Stacy A. Adams, Diego Scacalossi Voltan

Department of Agronomy and Horticulture: Faculty Publications

It is important for a greenhouse strawberry grower to know that their capillary mat (CapMat™) fertigation system is working correctly and that plants are receiving the correct amounts of water and fertilizer. Pots with soilless mix are not expected to hold more than 70% water on a volumetric basis. Pots with less than 40% water content continuously are not supplied enough water and nutrients to the plants. Typically, pots located near the manifold distribution system get a little more water than those at the other locations, but water use will really vary according to the factors listed above as well …

Morphological And Ecological Investigations Of Species Of Bulrush (Scirpus) In Illinois, Julian G. Moore

Masters Theses

Two closely related species of bulrush, Scirpus atrovirens (Green bulrush) and Scirpus georgianus (Georgia bulrush), are widely distributed in Illinois. They are difficult to separate in the field, but readily distinguishable under magnification in the lab. These two species have been found in moist meadows, shallow marshes, edges of wet forests, and ditches. The objective of this study was to evaluate the morphological and ecological distinctness of the species with the aim toward discovering and describing other features to distinguish them reliably. Eighty plants of Scirpus atrovirens and 80 of Scirpus georgianus were examined. Fifty S. atrovirens and 50 S. …

Lichens Of Six Vernal Pools In Acadia National Park, Me, Usa, J. Barton, B. Ciccotelli, J. E. Gall, F. C. Olday, B. Connery, T. B. Harris, A. M. Fryday, Nishanta Rajakaruna

Faculty Publications, Biological Sciences

Whereas lichen-habitat relations have been well-documented globally, literature on lichens of vernal pools is scant. We surveyed six vernal pools at Acadia National Park on Mount Desert Island, Maine, USA for their lichen diversity. Sixty-seven species were identified, including seven species that are new reports for Acadia National Park: Fuscidea arboricola, Hypogymnia incurvoides, Lepraria finkii, Phaeographis inusta, Ropalospora viridis, Usnea flammea, and Violella fucata. Five species are considered uncommon or only locally common in New England: Everniastrum catawbiense, Hypogymnia krogiae, Pseudevernia cladonia, Usnea flammea, and Usnea merrillii. This work represents the first survey of lichens from vernal pools in Acadia …

Sarpa Salpa Herbivory On Shallow Reaches Of Posidonia Oceanica Beds, Latina Steele, Kelly M. Darnell, Just Cebrián, Jose Luis Sanchez-Lizaso

Biology Faculty Publications

Sarpa salpa herbivory on shallow reaches of Posidonia oceanica beds.— Here, we examined the temporal and small–scale spatial variability of grazing by the herbivorous fish Sarpa salpa on shallow beds of the temperate seagrass Posidonia oceanica. Herbivory intensity expressed as the percent of leaf area taken by fish bites was higher in September 2006 than in February 2007, and at 0.5 m than at 1.5 m during both sampling times. All S. salpa feeding at the shallow locations studied were juveniles, with bite sizes ranging from 0.03 to 0.62 cm2. Juveniles feeding at 1.5 m were larger in February 2007 …

The Movement Ecology Of Seagrasses, Kathryn Mcmahon, Kor-Jent Van Dijk, Leonardo Ruiz-Montoya, Gary A. Kendrick, Siegfried L. Krauss, Michelle Waycott, Jennifer Verduin, Ryan Lowe, John Statton, Eloise Brown, Carlos Duarte

Research outputs 2014 to 2021

A movement ecology framework is applied to enhance our understanding of the causes, mechanisms and consequences of movement in seagrasses: marine, clonal, flowering plants. Four life-history stages of seagrasses can move: pollen, sexual propagules, vegetative fragments and the spread of individuals through clonal growth. Movement occurs on the water surface, in the water column, on or in the sediment, via animal vectors and through spreading clones. A capacity for long-distance dispersal and demographic connectivity over multiple timeframes is the novel feature of the movement ecology of seagrasses with significant evolutionary and ecological consequences. The space–time movement footprint of different life-history …

Corn Disease Update, Tamra A. Jackson-Ziems, Thomas W. Dorn

Department of Plant Pathology: Faculty Publications

The growing conditions during 2013 contributed to several disease problems in corn. Cold and wet conditions early led to development of seedling diseases. The hail-damaged corn in many areas of the state during the season led to ear rot diseases that were exacerbated by cooler conditions and increased grain moisture. Diseases have been a problem throughout the season and could extend beyond harvest into storage of some corn.

Arabidopsis Msl10 Has A Regulated Cell Death Signaling Activity That Is Separable From Its Mechanosensitive Ion Channel Activity, Kira M. Veley, Grigory Maksaev, Elizabeth M. Frick, Emma January, Sarah C. Kloepper, Elizabeth S. Haswell

Biology Faculty Research

Members of the MscS superfamily of mechanosensitive ion channels function as osmotic safety valves, releasing osmolytes under increased membrane tension. MscS homologs exhibit diverse topology and domain structure, and it has been proposed that the more complex members of the family might have novel regulatory mechanisms or molecular functions. Here, we present a study of MscS-Like (MSL)10 from Arabidopsis thaliana that supports these ideas. High-level expression of MSL10-GFP in Arabidopsis induced small stature, hydrogen peroxide accumulation, ectopic cell death, and reactive oxygen species- and cell death-associated gene expression. Phosphomimetic mutations in the MSL10 N-terminal domain prevented these phenotypes. The phosphorylation …