Digital Commons Network^™

Partridge Berry: Simple Beauty Belies Complexity, W. John Hayden

Biology Faculty Publications

Superficially, plants seem so simple. Rooted in place, they do not move around. And while plant growth is a dynamic process, without time-lapse photography, growth events are so imperceptibly slow that, to us impatient humans, plants seem both immobile and static. Nevertheless, there is a lot going on inside the plant body, and this is especially true for the events of reproduction that play out inside flowers and fruits. As one of my students recently commented, “I used to think it was just a matter of pollen plus stigma and, presto-change-o, seeds happen.” That student, I hope, learned otherwise, as …

Processing Quality Of Potato Tubers Produced During Autumn And Spring And Stored At Different Temperatures, Sergio T. De Freitas, Engil Isadora Pujol Pereira, Ana Cecilia S. Gomez, Auri Brackmann, Fernando Nicoloso, Dilson A. Bisognin

School of Earth, Environmental, & Marine Sciences Faculty Publications

The objective of this work was to access processing quality of potato clones (Solanum tuberosum) Asterix, SMINIA793101-3, and Missaukee cultivated during spring and autumn growing seasons and stored at 4, 8, 12, or 25ºC. Clones grown in spring had shorter dormancy than clones grown in autumn. Potato tubers grown in spring and autumn and stored at 4ºC, as well as tubers grown in autumn and stored at 8ºC had no sprouting for six months. Among clones grown in autumn, the longest dormancy period during storage at 12ºC was observed in the clone SMINIA793101-3, and at 25ºC was in the clone …

Spatial Genetic Variation Among Spodoptera Frugiperda (Lepidoptera: Noctuidae) Sampled From The United States, Puerto Rico, Panama, And Argentina, Difabachew K. Belay, Pete L. Clark, Steven R. Skoda, David J. Isenhour, Jaime Molina-Ochoa, Claudia Gianni, John E. Foster

Department of Entomology: Faculty Publications

Spatial genetic variability of the fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), was studied by collecting samples from 31 locations in the United States, Argentina, Panama, and Puerto Rico, and then using amplified fragment length polymorphism to detect genetic variation. Analysis of molecular variance showed significant genetic variation in fall armyworm among all (28%) sample locations and individuals within (71%) sample locations; genetic variation of fall armyworm was minimal between sample locations grouped into regions. The pairwise fixation index (F_ST) comparisons showed significant genetic differentiation (0.288) among the 31 locations. However, dendrograms of results from cluster …

Genetic Differentiation Of Western Corn Rootworm Populations (Coleoptera: Chrysomelidae) Relative To Insecticide Resistance, Hong Chen, Haichuan Wang, Blair D. Siegfried

Department of Entomology: Faculty Publications

Abstract

As the single most important pest of field corn, Zea mays L., throughout most of the Corn Belt, the western corn rootworm, Diabrotica virgifera virgifera LeConte (Coleoptera: Chrysomelidae), has undergone repeated selection for resistance to a variety of insecticides that persist widely among Nebraska populations. In this study, we used 11 microsatellite markers to genotype two populations with high levels of resistance to methyl-parathion and aldrin (Polk and Stromsburg), two populations with low and intermediate levels of resistance (Mead and Clay Center) from Nebraska, and one population from outside the Corn Belt (Safford, Arizona). The genetic diversity measured by …

Bean Leaf Beetle (Coleoptera: Chrysomelidae) And Bean Pod Mottle Virus In Soybean: Biology, Ecology, And Management, Buyung A. R. Hadi, Jeffrey D. Bradshaw, Marlin E. Rice, John J. Hill

Department of Entomology: Faculty Publications

Bean leaf beetle, Cerotoma trifurcata (Förster), is a pest of soybean found in many production areas in the United States. The bean leaf beetle larvae feed on soybean root nodules, whereas the adults feed on the above ground parts of soybean such as cotyledon, leaves, and pods. Bean leaf beetle is also a very efficient vector of Bean pod mottle virus, a widespread virus of soybean in the south and southeastern United States with recent expansion into the north central region of the country. This article summarizes bean leaf beetle biology, ecology, and its impact on soybean production in the …

Plant Wounding And Ophiostoma Mitovirus 3a (Omv3a) Influence Infection Of Creeping Bentgrass By Sclerotinia Homoeocarpa, Angela M. Orshinsky, Michael J. Boehm, Greg J. Boland

Department of Plant Pathology: Faculty Publications

Colonization and lesion development by virulent, asymptomatic and hypovirulent isolates of Sclerotinia homoeocarpa on nonwounded (NW) and wounded (W) leaves of creeping bentgrass were characterized. Hypovirulent and asymptomatic isolates contain the fungal virus, Ophiostoma mitovirus 3a, and virulent isolates are virus-free. On NW leaves, all isolates infected leaves with appressoria along cell walls and through stomata by 48 hours post-inoculation (hpi). Inter- and intracellular hyphae formed on heavily colonized, NW leaves at 96 hpi. Wound-inoculated grass had a colonization front characterized by inter- and intracellular hyphal colonization within nonsymptomatic tissues at 8 hpi by direct infection of the wound …

Effects Of The Manipulation Of Aboveground Plant Diversity In Restoration Management On The Diversity Of Belowground Arthropod Assemblage, Claire E. Gilmore

College of Science and Health Theses and Dissertations

A missing element in restoring belowground soil systems to a relatively healthy state may lie in promoting microarthropod diversity. By contributing to healthy nutrient cycling and assisting in the breakdown of leaf litter a diverse microarthropod population helps improve the overall soil quality. My study evaluated how current restoration practices aimed at maintaining aboveground diversity affects belowground microarthropod populations. I examined how the aboveground manipulation of plant diversity in restoration management practices affects the hyperdiverse assemblage of belowground arthropod communities. Additionally, I examined the relationship between soil nutrient content and microarthropod diversity. This study was conducted within the boundaries of …

Glycolate Oxidase Modulates Reactive Oxygen Species–Mediated Signal Transduction During Nonhost Resistance In Nicotiana Benthamiana And Arabidopsis, Clemencia M. Rojas, Muthappa Senthil-Kumar, Keri Wang, Choong-Min Ryu, Amita Kaundal, Kirankumar S. Mysore

Plants, Soils, and Climate Faculty Publications

In contrast to gene-for-gene disease resistance, nonhost resistance governs defense responses to a broad range of potential pathogen species. To identify specific genes involved in the signal transduction cascade associated with nonhost disease resistance, we used a virus-induced gene-silencing screen in Nicotiana benthamiana, and identified the peroxisomal enzyme glycolate oxidase (GOX) as an essential component of nonhost resistance. GOX-silenced N. benthamiana and Arabidopsis thaliana GOX T-DNA insertion mutants are compromised for nonhost resistance. Moreover, Arabidopsis gox mutants have lower H2O2 accumulation, reduced callose deposition, and reduced electrolyte leakage upon inoculation with hypersensitive response–causing nonhost pathogens. Arabidopsis gox mutants were not …

Alteration Of Tobacco Alkaloid Content Through Modification Of Specific Cytochrome P450 Genes, Ralph E. Dewey, Balaz Siminszky, Steven W. Bowen, Lily Gavilano

Plant and Soil Sciences Faculty Patents

Compositions and methods for reducing the level of nornicotine and N′-nitrosonornicotine (NNN) in Nicotiana plants and plant parts thereof are provided. The compositions comprise isolated polynucleotides and polypeptides for cytochrome P450s that are involved in the metabolic conversion of nicotine to nornicotine in these plants. Expression cassettes, vectors, plants, and plant parts thereof comprising inhibitory sequences that target expression or function of the disclosed cytochrome P450 polypeptides are also provided. Methods for the use of these novel sequences to inhibit expression or function of cytochrome P450 polypeptides involved in this metabolic conversion are also provided. The methods find use in …

Evolution Of Plant Sucrose Uptake Transporters, Anke Reinders, Alicia B. Sivitz, John M. Ward

Dartmouth Scholarship

In angiosperms, sucrose uptake transporters (SUTs) have important functions especially in vascular tissue. Here we explore the evolutionary origins of SUTs by analysis of angiosperm SUTs and homologous transporters in a vascular early land plant, Selaginella moellendorffii, and a non-vascular plant, the bryophyte Physcomitrella patens, the charophyte algae Chlorokybus atmosphyticus, several red algae and fission yeast, Schizosaccharomyces pombe. Plant SUTs cluster into three types by phylogenetic analysis. Previous studies using angiosperms had shown that types I and II are localized to the plasma membrane while type III SUTs are associated with vacuolar membrane. SUT homologs were …

Analysis Of Saint John's Maple Syrup Records: 1942-2009, Stephen G. Saupe

Headwaters

No abstract provided.

Diversification And Expression Of The Pin, Aux/Lax, And Abcb Families Of Putative Auxin Transporters In Populus, Nicola Carraro, Tracy Elizabeth Tisdale-Orr, Ronald Matthew Clouse, Anne Sophie Knöller, Rachel Spicer

Botany Faculty Publications

Intercellular transport of the plant hormone auxin is mediated by three families of membrane-bound protein carriers, with the PIN and ABCB families coding primarily for efflux proteins and the AUX/LAX family coding for influx proteins. In the last decade our understanding of gene and protein function for these transporters in Arabidopsis has expanded rapidly but very little is known about their role in woody plant development. Here we present a comprehensive account of all three families in the model woody species Populus, including chromosome distribution, protein structure, quantitative gene expression, and evolutionary relationships. The PIN and AUX/LAX gene families …

Agricultural Research Magazine February 2012

Agricultural Research Magazine

Agricultural Research Magazine February 2012 whole issue

Fighting Nitrate in the Trenches

Multi-Pronged Fight Against Zebra Chip Disease In Potatoes, Jan Suszkiw

Agricultural Research Magazine

Thanks to the investigations of scientiststurned- detectives, potato growers in the western United States and abroad now know the identities of the pathogen and insect responsible for outbreaks of the costly tuber disease known as “zebra chip.”

So named for the dark stripes it forms inside afflicted tubers when cut and fried to make chips or cooked at high temperatures for other dishes, zebra chip has caused millions of dollars in production and processing losses since its first reported U.S. occurrence in potato fields near McAllen and Pearsall, Texas, in 2000. The disease, whose above-ground symptoms include necrosis and purplish, …

A Subgroup Of Sgs3-Like Proteins Act Redundantly In Rna-Directed Dna Methylation, Meng Xie, Guodong Ren, Pedro Costa-Nunes, Olga Pontes, Bin Yu

Center for Plant Science Innovation: Faculty Publications

Plant specific SGS3-like proteins are composed of various combinations of an RNA-binding XS domain, a zinc-finger zf-XS domain, a coil–coil domain and a domain of unknown function called XH. In addition to being involved in de novo 2 (IDN2) and SGS3, the Arabidopsis genome encodes 12 uncharacterized SGS3-like proteins. Here, we show that a group of SGS3-like proteins act redundantly in RNA-directed DNA methylation (RdDM) pathway in Arabidopsis. Transcriptome co-expression analyses reveal significantly correlated expression of two SGS3-like proteins, factor of DNA methylation 1 (FDM1) and FDM2 with known genes required for RdDM. The fdm1 and fdm2 double mutations …

Nebline, February 2012

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Feature: 4-H Diamond Clover Program Helps Youth Plan and Achieve Goals

Farm Views

Urban Agriculture

Food & Fitness

Home & Family Living

Horticulture

Environmental Focus

4-H & Youth

Community Focus

Extension Calendar

Nutrition Education Program

Family and Community Education (FCE) Clubs

and other extension news and events

Battling Problem Pests In Paradise, Stephanie Yao, Dennis O’Brien

Agricultural Research Magazine

Sandy beaches, blue water, warm weather, and—invasive insects? One of these things certainly doesn’t belong. When we think of island paradise, invasive insects don’t usually come to mind. But these pesky pests are a problem for countries all over the world.

In two separate projects, Agricultural Research Service scientists are working with their Azorean and French Polynesian counterparts to help control invasive insects there. Since these pests are also invasive in the United States, these collaborations may have mutual benefit. So far, the results have been promising.

An Infestation in the Azores

Off the coast of Portugal lies an archipelago …

Vitamin Deficiencies In Humans: Can Plant Science Help?, Teresa B. Fitzpatrick, Gilles J. C. Basset, Patrick Borel, Fernando Carrari, Dean Dellapenna, Paul D. Fraser, Hanjo Hellmann, Sonia Osorio, Christophe Rothan, Victoriano Valpuesta, Catherine Caris-Veyrat, Alisdair R. Fernie

Center for Plant Science Innovation: Faculty Publications

The term vitamin describes a small group of organic compounds that are absolutely required in the human diet. Although for the most part, dependency criteria are met in developed countries through balanced diets, this is not the case for the five billion people in developing countries who depend predominantly on a single staple crop for survival. Thus, providing a more balanced vitamin intake from high-quality food remains one of the grandest challenges for global human nutrition in the coming decade(s). Here, we describe the known importance of vitamins in human health and current knowledge on their metabolism in plants. Deficits …

Single-Molecule Analysis Of The Microtubule Cross-Linking Protein Map65-1 Reveals A Molecular Mechanism For Contact-Angle-Dependent Microtubule Bundling, Amanda Tulin, Sheri Mcclerklin, Yue Huang, Ram Dixit

Biology Faculty Research

Bundling of microtubules (MTs) is critical for the formation of complex MT arrays. In land plants, the interphase cortical MTs form bundles specifically following shallow-angle encounters between them. To investigate how cells select particular MT contact angles for bundling, we used an in vitro reconstitution approach consisting of dynamic MTs and the MT-cross-linking protein MAP65-1. We found that MAP65-1 binds to MTs as monomers and inherently targets antiparallel MTs for bundling. Dwell-time analysis showed that the affinity of MAP65-1 for antiparallel overlapping MTs is about three times higher than its affinity for single MTs and parallel overlapping MTs. We also …

The Hormonal Characterization And Mapping Of A New Jasmonate Hypersensitive Mutant (Jah2) In Arabidopsis Thaliana, Hsin-Ho Wei

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

Jasmonic acid (JA) is a phytohormone that plays important roles in growth, development, and defense in plants. Although many functions and mechanisms of JA are known, some pathways are still unclear. One of the simplest approaches to understanding JA signal transduction is isolating mutants that respond abnormally to JA. From the defects of such mutants we can determine the regulatory functions of JA. jasmonate hypersensitive 2 (jah2) is a JA hypersensitive mutant. JA normally inhibits the root growth of plants and the jah2 mutant has an even shorter root compared with wild-type Col-0 (wild type) under the same …

Effect Of Soil Salinity Level On Development And Functioning Of Endomycorrhizae In The Groundcover Wedelia Trilobata (L.) Grown On Dune Sand From The Uae, Farivash Abdullah Rajaei

Theses

In semi-arid parts of the world such as the U A E, salinity is a major constraint to plant growth and development. More than 80 % of a land plants live in symbiosis with soil fungi of the Glomeromycota. These are also called arbuscular mycorrhizal fungi (AMF), and have been shown to contribute to growth and nutrient uptake of a broad range of agricultural plants. A positive effect of the AM symbiosis on plant performance under salinity has often been observed, but the precise mechanisms behind this effect are unknown to date. Mycotrophic plants common I) grown on saline sandy …

Herbivory Affects Patterns Of Plant Reproductive Effort And Seed Production, Natalie M. West

School of Biological Sciences: Dissertations, Theses, and Student Research

Insect herbivory can have a major influence on plant reproduction, and potentially drive selection for strategies that reduce or resist herbivore effects. I used a combination of field experiments and ecological modeling to examine how modifications in the patterns and timing of reproductive investment might ameliorate the consequences of herbivore damage for plant reproduction. I performed experiments to examine how changes in reproductive effort after apical damage and reduction of insect herbivory affected seed production in two thistles native to Nebraska. I then used field data to parameterize a life history model predicting the resource allocation among buds and size …

Chimeric Isoprenoid Synthases And Uses Thereof, Joe Chappell, Kyoungwhan Back

Plant and Soil Sciences Faculty Patents

Disclosed is a chimeric isoprenoid synthase polypeptide including a first domain from a first isoprenoid synthase joined to a second domain from a second, heterologous isoprenoid synthase, whereby the chimeric isoprenoid synthase is capable of catalyzing the production of isoprenoid reaction products that are not produced in the absence of the second domain of the second, heterologous isoprenoid synthase. Also disclosed is a chimeric isoprenoid synthase polypeptide including an asymmetrically positioned homologous domain, whereby the chimeric isoprenoid synthase is capable of catalyzing the production of isoprenoid reaction products that are not produced when the domain is positioned at its naturally-occurring …

2011 Vadose Zone Nitrate Study At Hastings, Ne (Revised), Roy F. Spalding, Martin Toavs

Department of Agronomy and Horticulture: Faculty Publications

In an effort to assist Hastings Utilities in the management of their well-head protection area (WHP A) and to protect the groundwater from the impact of nitrate loading from potential nonpoint and point sources, Hastings Utilities subcontracted with the Department of Agronomy and Horticulture at the University of Nebraska for deep vadose zone coring. Continuous 60-ft soil cores were obtained at 36 sites within the apparent WHP A (Figure 1). The sites were selected by Marty Stange on the basis of availability for sampling, management, landuse , cropping history, and location within the WHPA. Nitrogen analyses of these deep soil …

Two New Species Of Trigonotylus (Hemiptera: Heteroptera: Miridae: Stenodemini) From Western Canada And Northwestern United States, G G.E. Scudder, Michael D. Schwartz

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

Genome-Wide Analysis Of Syntenic Gene Deletion In The Grasses, James C. Schnable, Michael Freeling, Eric Lyons

Department of Agronomy and Horticulture: Faculty Publications

The grasses, Poaceae, are one of the largest and most successful angiosperm families. Like many radiations of flowering plants, the divergence of the major grass lineages was preceded by a whole-genome duplication (WGD), although these events are not rare for flowering plants. By combining identification of syntenic gene blocks with measures of gene pair divergence and different frequencies of ancient gene loss, we have separated the two subgenomes present in modern grasses. Reciprocal loss of duplicated genes or genomic regions has been hypothesized to reproductively isolate populations and, thus, speciation. However, in contrast to previous studies in yeast and teleost …

What Fescue Toxicosis Is Really Doing Inside Your Animals, Glen E. Aiken

Forage Symposium at the Kentucky Cattlemen’s Convention

Eighty years have passed since Dr. F.N. Fergus collected seed of tall fescue from that hillside at the Suiter Farm in Menifee County that led to the commercial release of the cultivar ‘Kentucky 31’. Fescue provided an opportunity to replace the briar and weed patches that dominated the rocky hillsides of Kentucky with productive forage. Plantings of tall fescue were numerous in the state during the 1940s and 1950s, and its hardiness and adaptability resulted in the grass spreading over much of the middle and upper southeastern USA, eventually covering a region we now call the “fescue belt”. It did …

Volume 5, Chapter 7-3: Gardening: Private Moss Gardens, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.

Volume 5, Chapter 5: Construction, Janice M. Glime

Bryophyte Ecology Subchapters

No abstract provided.

Soybean Disease Profiles I: Foliar Diseases, Loren J. Giesler, Robert M. Harveson, Tamra A. Jackson-Ziems, Kevin A. Korus, Bo Liu, Stephen N. Wegulo

Department of Plant Pathology: Faculty Publications

Extension Circular 1093 (EC1903).

Disease photographs and descriptions of Bacterial Blight, Bacterial Pustule, Brown Spot, Cercospora Leaf Blight and Purple Seed Stain, Downy Mildew, Frogeye Leaf Spot, Soybean Rust, Powdery Mildew, and Bean Pod mottle and Soybean Mosaic.