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Genetic And Hybridization Evidence Confirms That A Geographic Population Of Gonatocerus Morrilli (Hymenoptera: Mymaridae) From California Is A New Species: Egg Parasitoids Of The Glassy-Winged Sharpshooter Homalodisca Coagulata (Homoptera: Cicadellidae), Jesse H. De León, Walker A. Jones, Mamoudou Sétamou, David J. W. Morgan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

We investigated the differentiation and reproductive isolation among different geographic populations of Gonatocerus morrilli, egg parasitoids of the glassy-winged sharpshooter (Homalodisca coagulata), to confirm previous observations that there may exist a cryptic species complex or a new species. Two mitochondrial genes [cytochrome oxidase subunits I (COI) and II (COII)] and the internal transcribed spacer region 2 (ITS2) of several individuals per population were sequenced. G. morrilli populations from Texas (TX), Florida (FL), California (CA), and an outgroup (G. ashmeadi) were analyzed. For comparison, a population from Argentina (G. annulicornis) morphologically similar to G. …

Biotinylation Of K8 And K12 Co-Occurs With Acetylation And Mono-Methylation In Human Histone H4, Yap Ching Chew, Ashraf S. Raza, Gautam Sarath, Janos Zempleni

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Histones H1, H2A, H2B, H3, and H4 are proteins that are critical for folding of DNA into chromatin. Posttranslational acetylation, methylation, and biotinylation of histones participate in gene silencing, mitotic condensation of chromatin, and the cellular response to DNA damage. Various modifications of histones are known to interact ("cross-talk") in chromatin-remodeling events; interactions may be synergistic or antagonistic. Here, we sought to identify biotinylation sites in human histone H4 by using mass spectrometry (MS/MS), and we sought to determine whether biotinylation co-exists with acetylation and methylation in the same H4 molecule. Nuclear histones from human lymphoid (Jurkat) cells were digested …

Slow Ligand Binding Kinetics Dominate Ferrous Hexacoordinate Hemoglobin Reactivities And Reveal Differences Between Plants And Other Species, Benoit J. Smagghe, Gautam Sarath, Emily Ross, Jean-Louis Hilbert, Mark S. Hargrove

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Hexacoordinate hemoglobins are found in many living organisms ranging from prokaryotes to plants and animals. They are named “hexacoordinate” because of reversible coordination of the heme iron by a histidine side chain located in the heme pocket. This endogenous coordination competes with exogenous ligand binding and causes multiphasic relaxation time courses following rapid mixing or flash photolysis experiments. Previous rapid mixing studies have assumed a steady-state relationship between hexacoordination and exogenous ligand binding that does not correlate with observed time courses for binding. Here, we demonstrate that this assumption is not valid for some hexacoordinate hemoglobins, and that multiphasic time …

Nutrient Uptake Of Maize Affected By Nitrogen And Potassium Fertility In A Humid Subtropical Environment, H. Arnold Bruns, M. Wayne Ebelhar

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Nitrogen (N) and potassium (K) fertility management of maize (Zea mays L.) in the humid subtropical Mississippi Delta may differ from a temperate climate because of its use in rotation with cotton (Gossypium hirsutum L.), soil temperatures rarely falling to 0 °C, and heavy winter rains that facilitate nutrient losses. An experiment to determine the [N] (concentration = [ ]), phosphorus [P], [K], calcium [Ca], magnesium [Mg], iron [Fe], manganese [Mn], zinc [Zn], and copper [Cu] and their total contents plant^-1 of maize grown in rotation with cotton, using N fertility levels of (134, 179, 224, 269, …

2006 Fall Seed Book, Nebraska Crop Improvement Association

Nebraska Crop Improvement Association Seed Guides

FOUNDATION SEED

WINTER WHEAT VARIETY CHARACTERISTICS - 2006

HARD RED WINTER WHEAT

HARD WHITE WINTER WHEAT

TRITICALE

LANDSCAPE QUALITY TURFGRASS SOD

TURFGRASSES

COOL-SEASON GRASSES

APPROVED SEED CONDITIONERS

CUSTOM CERTIFIED CONDITIONERS

2006 NCIA MEMBERS

A Highly Efficient Transient Protoplast System For Analyzing Defence Gene Expression And Protein–Protein Interactions In Rice, Songbiao Chen, Lizen Tao, Lirong Zeng, Miguel E. Vega-Zanchez, Kenji Umemura, Guo-Liang Wang

Center for Plant Science Innovation: Faculty and Staff Publications

The transient assay system based on mesophyll or cultured cell-derived protoplasts has been exploited in several plant species and has become a powerful tool for rapid gene functional analysis and biochemical manipulations. However, the system has not been widely used in rice owing to the difficulties in large-scale isolation of viable rice protoplasts from leaves or suspension-cultured cells. Here, we describe a significantly improved method to isolate a large number of protoplasts from stem and sheath tissues of both young and mature plants. High-level coexpression of multiple constructs and efficient suppression of exogenous and endogenous genes were observed in the …

Trees And Ice Storms: The Development Of Ice Storm–Resistant Urban Tree Populations (Second Edition), Richard J. Hauer, Jeffrey O. Dawson, Les P. Werner

USDA Forest Service / UNL Faculty Publications

Severe ice storms occur every year in the United States and Canada, particularly in the midwestern and eastern regions of the United States. Along with fires and wind, ice storms are a frequent and major natural disturbance factor in eastern deciduous forests. Likewise ice storms are responsible for deaths and injuries of people and cause dramatic damage and tree loss to urban forests. Ice storms annually result in millions of dollars in loss, and potentially billions of dollars in losses for extreme and widespread ice storms. Damage to electric distribution systems, blocked roadways, and property damage from fallen trees and …

Evaluation Of The Single Kernel Characterization System (Skcs) For Measurement Of Sorghum Grain Attributes, S. R. Bean, O. K. Chung, M. R. Tuinstra, Jeffrey F. Pedersen, J. Erpelding

Department of Agronomy and Horticulture: Faculty Publications

The single kernel characterization system (SKCS) has been widely used in the wheat industry, and SKCS parameters have been linked to end-use quality in wheat. The SKCS has promise as a tool for evaluating sorghum grain quality. However, the SKCS was designed to analyze wheat, which has a different kernel structure from sorghum. To gain a better understanding of the meaning of SKCS predictions for grain sorghum, individual sorghum grains were measured for length, width, thickness (diameter), and weight by laboratory methods and by the SKCS. SKCS predictions for kernel weight and thickness were highly correlated to laboratory measurements. However, …

Guide For Weed Management In Nebraska, Mark L. Bernards, Stevan Z. Knezevic, Roch E. Gaussoin, Drew J. Lyon, Brady F. Kappler, Alex Martin, Robert N. Klein, Fred Roeth, Robert G. Wilson, Robert A. Masters, Patrick J. Shea, Larry D. Schulze

Department of Agronomy and Horticulture: Faculty Publications

Each year we strive to provide a publication that is updated, informative, and easy to use. Last year’s edition has been revised to include the latest research-based information and several new sections outlined below. We hope you find these revisions useful and that they make this guide an even better resource than the previous edition.

Chemical Composition And Response To Dilute-Acid Pretreatment And Enzymatic Saccharification Of Alfalfa, Reed Canarygrass, And Switchgrass, Bruce S. Dien, Hans-Joachim G. Jung, Kenneth P. Vogel, Michael D. Casler, Joann F. S. Lamb, Loren Iten, Robert C. Mitchell, Gautum Sarath

Department of Agronomy and Horticulture: Faculty Publications

Alfalfa stems, reed canarygrass, and switchgrass; perennial herbaceous species that have potential as biomass energy crops in temperate regions; were evaluated for their bioconversion potential as energy crops. Each forage species was harvested at two or three maturity stages and analyzed for carbohydrates, lignin, protein, lipid, organic acids, and mineral composition. The biomass samples were also evaluated for sugar yields following pretreatment with dilute sulfuric followed by enzymatic saccharification using a commercial cellulase preparation. Total carbohydrate content of the plants varied from 518 to 655 g kg^-1 dry matter (DM) and cellulose concentration from 209 to 322 g kg …

Mutations In Arabidopsis Yellow Stripe-Like1 And Yellow Stripe-Like3 Reveal Their Roles In Metal Ion Homeostasis And Loading Of Metal Ions In Seeds, Brian M. Waters, Heng-Hsuan Chu, Raymond J. Didonato, Louis A. Roberts, Robynn B. Eisley, Brett Lahner, David E. Salt, Elsbeth L. Walker

Department of Agronomy and Horticulture: Faculty Publications

Here, we describe two members of the Arabidopsis (Arabidopsis thaliana) Yellow Stripe-Like (YSL) family, AtYSL1 and AtYSL3. The YSL1 and YSL3 proteins are members of the oligopeptide transporter family and are predicted to be integral membrane proteins. YSL1 and YSL3 are similar to the maize (Zea mays) YS1 phytosiderophore transporter (ZmYS1) and the AtYSL2 iron (Fe)-nicotianamine transporter, and are predicted to transport metal-nicotianamine complexes into cells. YSL1 and YSL3 mRNAs are expressed in both root and shoot tissues, and both are regulated in response to the Fe status of the plant. β-Glucuronidase reporter expression, driven by …

Soybean Cultivars Resulted From More Recombination Events Than Unselected Lines In The Same Population, T. R. Stefaniak, D. L. Hyten Jr., V. R. Pantalone, A. Klarer, T. W. Pfeiffer

Department of Agronomy and Horticulture: Faculty Publications

The selection of superior adapted cultivars has contributed to the doubling of soybean [Glycine max (L.) Merr.] yields in the USA since 1930. Genetic variation was required for this selection to be effective. The objective of this study was to evaluate the importance of homologous chromosome meiotic recombination in the creation of soybean cultivars. A set of 10 adapted high-yielding cultivars selected from the cross ‘Williams’ × ‘Essex’ was com-pared with a set of 156 random recombinant inbred lines (RILs) from the same population. Crossover events were identified using 143 simple sequence repeat (SSR) markers span-ning all 20 soybean …

Resistance Gene Analog Polymorphism (Rgap) Markers Co-Localize With Disease Resistance Genes And Qtl In Common Bean, Nedim Mutlu, Phillip Miklas, Dermot Coyne

Department of Agronomy and Horticulture: Faculty Publications

Resistance (R) genes containing nucleotide-binding site (NBS)-leucine rich repeats (LRR) are the most prevalent types of R gene in plants. The objective of this study was to develop PCR-based R-gene analog polymorphism (RGAP) markers for common bean (Phaseolus vulgaris L). Twenty degenerate primers were designed from the conserved kinase-1a (GVGKTT) and hydrophobic domains (GLPLAL) of known NBSLRR type R-genes and from EST databases. Sixty-six of the 100 primer combinations tested yielded polymorphism. Thirty-two RGAP markers were mapped in the BAT 93/Jalo EEP558 core mapping population for common bean. The markers mapped to 10 of 11 linkage groups with a …

Performance Of Weedsoft For Predicting Soybean Yield Loss, Shawn M. Hock, Stevan Z. Knezevic, Alex Martin, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Decision support systems (DSSs) have been developed to assist producers and consultants with weed management decisions. WeedSOFT is a DSS currently used in several states in the northcentral region of the United States. Accurate estimates of crop yield loss due to weed interference are required for cost-effective weed management recommendations. WeedSOFT uses competitive indices (CIs) to predict crop yield loss under multiple weed species, weed densities, and relative times of weed emergence. Performance of several WeedSOFT versions to predict soybean yield loss from weed competition was evaluated using CI values in WeedSOFT version 9.0 compared to new CI values calculated …

Sediment Transport Model For Seepage Erosion Of Streambank Sediment, G. A. Fox, G. V. Wilson, R. K. Periketi, R. F. Cullum

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Erosion by lateral, subsurface flow is known to erode streambank sediment in numerous geographical locations; however, the role of seepage erosion on mass failure of streambanks is not well understood. In the absence of an established sediment transport model for seepage erosion, the objectives of this research were to investigate the mechanisms of erosion due to concentrated, lateral subsurface flow and develop an empirical sediment transport model for seepage erosion of noncohesive sediment on near-vertical streambanks. Laboratory experiments were performed using a two-dimensional soil lysimeter of a reconstructed streambank profile packed with three different soil layers to mimic seepage erosion …

Separation And Identification Of Soybean Leaf Proteins By Two-Dimensional Gel Electrophoresis And Mass Spectrometry, Chenping Xu, Wesley M. Garrett, Joseph Sullivan, Thomas J. Caperna, Savithiry Natarajan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

To establish a proteomic reference map for soybean leaves, we separated and identified leaf proteins using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry (MS). Tryptic digests of 260 spots were subjected to peptide mass fingerprinting (PMF) by matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. Fifty-three of these protein spots were identified by searching NCBInr and SwissProt databases using the Mascot search engine. Sixty-seven spots that were not identified by MALDI-TOF-MS analysis were analyzed with liquid chromatography tandem mass spectrometry (LC-MS/MS), and 66 of these spots were identified by searching against the NCBInr, SwissProt and expressed sequence tag (EST) databases. …

Effect Of Nitrogen Addition On The Comparative Productivity Of Corn And Velvetleaf (Abutilon Theophrasti), Darren C. Barker, Stevan Z. Knezevic, Alex R. Martin, Daniel T. Walters, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Weeds that respond more to nitrogen fertilizer than crops may be more competitive under high nitrogen (N) conditions. Therefore, understanding the effects of nitrogen on crop and weed growth and competition is critical. Field experiments were conducted at two locations in 1999 and 2000 to determine the influence of varying levels of N addition on corn and velvetleaf height, leaf area, biomass accumulation, and yield. Nitrogen addition increased corn and velvetleaf height by a maximum of 15 and 68%, respectively. N addition increased corn and velvetleaf maximum leaf area index (LAI) by up to 51 and 90%. Corn and velvetleaf …

Blue Mustard Control, Drew J. Lyon, Robert N. Klein, Robert G. Wilson

University of Nebraska-Lincoln Extension: Historical Materials

Blue mustard is a troublesome weed in winter wheat and alfalfa in central and western Nebraska. This NebGuide discusses methods of control.

Blue mustard [Chorispora tenella (Pallas) D.C.] was introduced into the United States from Siberia in 1929 and was first reported in Lewiston, Idaho. It was identified in Keith County, Nebraska in 1953. Blue mustard is a winter annual weed, with seed germinating in late summer and fall. The plant overwinters as a rosette. The flower stalk usually elongates, a process known as bolting, in March. With mild February weather, bolting may occur in early March. Cold weather …

Science-Based Organic Farming 2006: Toward Local And Secure Food Systems, Charles A. Francis, Katja Koehler-Cole, Twyla Hansen, Peter Skelton

Publications from the Center for Applied Rural Innovation (CARI)

Organic farming includes growing food and fiber—animals, agronomic crops, horticultural fruits and vegetables, related products—as one dynamic and rapidly evolving component of our complex U.S. food system. Even as more farmers are moving toward organic certification and participation in an environmentally sound and economically lucrative market, questions arise about the long-term social impacts and sustainability of a set of practices that has gone from a movement to an industry. Consolidations in the organic trade have brought multinational corporations to the table, as they have observed a grassroots activity that has grown by 20% per year for the past two decades, …

Nebline, January 2006

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

30 MyPyramid Steps to a Healthier You
Guide to Growing Amaryllis
Winter Care of Houseplants
Managing Dust Mites
Urban Pest Management Conference
You Caught Your Mouse — How About Cleanup?
Beginning Beekeeping 2-Day Workshop
Private Pesticide Applicator Certification
Is Burning Wood an Economically Feasible Option?
Crop Protection Clinic, Jan. 23
Acreage-Tough Plants
The Physical Resources of the Acreage—Part 1
Upcoming Acreage Insights Clinics
Meet the Grain Group
Mock Frozen “Peach” Daiquiri Recipe
Sit Less, Move More!
Low-Cost Indoor Avenues to Fitness
Home Energy Checkup
Household Hints: Cleaning silver by electrolysis
President’s Notes — Janet’s Jargon
FCE News & Events
Rokeby …

Snp-Phage – High Throughput Snp Discovery Pipeline, Lakshmi K. Matukumalli, John J. Grefenstette, David L. Hyten, Ik-Young Choi, Perry B. Cregan, Curt P. Van Tassell

Department of Agronomy and Horticulture: Faculty Publications

Background: Single nucleotide polymorphisms (SNPs) as defined here are single base sequence changes or short insertion/deletions between or within individuals of a given species. As a result of their abundance and the availability of high throughput analysis technologies SNP markers have begun to replace other traditional markers such as restriction fragment length polymorphisms (RFLPs), amplified fragment length polymorphisms (AFLPs) and simple sequence repeats (SSRs or microsatellite) markers for fine mapping and association studies in several species. For SNP discovery from chromatogram data, several bioinformatics programs have to be combined to generate an analysis pipeline. Results have to be stored in …

Application Of Machine Learning In Snp Discovery, Lakshmi K. Matukumalli, John J. Grefenstette, David L. Hyten, Ik-Young Choi, Perry B. Cregan, Curtis P. Van Tassell

Department of Agronomy and Horticulture: Faculty Publications

Background: Single nucleotide polymorphisms (SNP) constitute more than 90% of the genetic variation, and hence can account for most trait differences among individuals in a given species. Polymorphism detection software PolyBayes and PolyPhred give high false positive SNP predictions even with stringent parameter values. We developed a machine learning (ML) method to augment PolyBayes to improve its prediction accuracy. ML methods have also been successfully applied to other bioinformatics problems in predicting genes, promoters, transcription factor binding sites and protein structures. Results: The ML program C4.5 was applied to a set of features in order to build a SNP classifier …

Impacts Of Genetic Bottlenecks On Soybean Genome Diversity, D. L. Hyten, Qijian Song, Youlin Zhu, Ik-Young Choi, Randall L. Nelson, Jose M. Costa, James E. Specht, Randy C. Shoemaker, Perry B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Soybean has undergone several genetic bottlenecks. These include domestication in Asia to produce numerous Asian landraces, introduction of relatively few landraces to North America, and then selective breeding over the past 75 years. It is presumed that these three human-mediated events have reduced genetic diversity. We sequenced 111 fragments from 102 genes in four soybean populations representing the populations before and after genetic bottlenecks. We show that soybean has lost many rare sequence variants and has undergone numerous allele frequency changes throughout its history. Although soybean genetic diversity has been eroded by human selection after domestication, it is notable that …

Ethylene Could Influence Ferric Reductase, Iron Transporter, And H+-Atpase Gene Expression By Affecting Fer (Or Fer-Like) Gene Activity, Carlos Lucera, Brian M. Waters, Francisco Javier Romera, María José García, María Morales, Esteban Alcántara, Rafael Pérez-Vicente

Department of Agronomy and Horticulture: Faculty Publications

In previous works, it has been shown, by using ethylene inhibitors and precursors, that ethylene could participate in the regulation of the enhanced ferric reductase activity of Fe-deficient Strategy I plants. However, it was not known whether ethylene regulates the ferric reductase gene expression or other aspects related to this activity. This paper is a study of the effects of ethylene inhibitors and precursors on the expression of the genes encoding the ferric reductases and iron transporters of Arabidopsis thaliana (FRO2 and IRT1) and Lycopersicon esculentum (= Solanum lycopersicum) (FRO1 and IRT1) plants. The effects …

Early-Season Insect Defoliation Influences The Critical Time For Weed Removal In Soybean, Travis C. Gustafson, Stevan Z. Knezevic, Thomas E. Hunt, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

To develop more effective pest-management strategies, it is essential to understand how different pests interact with each other and the crop. Field studies were conducted in 2003 and 2004 at two Nebraska locations to determine the effects of early-season crop defoliation on the critical time for weed removal (CTWR) in narrow-row soybean. Three soybean defoliation levels were selected to simulate 0, 30, and 60% leaf tissue removal by the bean leaf beetle. Weeds were allowed to compete with the crop until V2, V4, V6, R3, and R5 growth stages. There were also season-long weedy and weed-free treatments. Results indicated that …

Plant Breeding Training In The U.S., P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

The plant breeding enterprise is large and highly interdisciplinary. In considering how to approach this topic, it is necessary to define who is a plant breeder for that defines the scope of this paper. For the purpose of this paper, a plant breeder will be defined as a person who is actively involved in creating new plant germplasm that may lead to new cultivars or be used as parents to create new cultivars of food, feed, fiber, and ornamental plants. This definition is deliberately narrow. For example it does not include those who are developing molecular markers for marker assisted …

Soil Organic Carbon Changes In Diversified Rotations Of The Western Corn Belt, Gary E. Varvel

Department of Agronomy and Horticulture: Faculty Publications

Sequestration and storage of carbon (C) by agricultural soils has been cited as one potential part of the solution to soil degradation and global climate change. However, C sequestration in soils is a slow and dynamic process. The objective of this study was to evaluate the effects of crop rotation and N fertilizer management on soil organic C (SOC) levels at several points in time during 18 yr of a long-term study in the Western Corn Belt. Seven cropping systems (three monoculture, two 2-yr, and two 4-yr rotations) with three levels of N fertilizer were compared. Soil samples were taken …

Anthropogenic Drivers Of Ecosystem Change: An Overview, Gerald C. Nelson, Elena Bennett, Asmeret A. Berhe, Kenneth G. Cassman, Ruth Defries, Thomas Dietz, Achim R. Dobermann, Andrew Dobson, Anthony Janetos, Marc Levy, Diana Marco, Nebojsa Nakicenovic, Brian O'Neill, Richard Norgaard, Gerhard Petschel-Held, Dennis Ojima, Prabhu Pingali, Robert Watson, Monika Zurek

Department of Agronomy and Horticulture: Faculty Publications

This paper provides an overview of what the Millennium Ecosystem Assessment (MA) calls “indirect and direct drivers” of change in ecosystem services at a global level. The MA definition of a driver is any natural or human-induced factor that directly or indirectly causes a change in an ecosystem. A direct driver unequivocally influences ecosystem processes. An indirect driver operates more diffusely by altering one or more direct drivers. Global driving forces are categorized as demographic, economic, sociopolitical, cultural and religious, scientific and technological, and physical and biological. Drivers in all categories other than physical and biological are considered indirect. Important …

Soybean Row Spacing And Weed Emergence Time Influence Weed Competitiveness And Competitive Indices, Shawn M. Hock, Stevan Z. Knezevic, Alex Martin, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Weed competitiveness can be quantified with the concept of competitive index (CI), a relative scale of weed competitiveness. Field studies were conducted in 2002 and 2003 in northeastern and southeastern Nebraska to evaluate the influence of soybean row spacing and relative weed emergence time on the competitiveness of major weed species in soybean. Ten weed species were seeded in soybean spaced 19 and 76 cm apart at the planting, emergence, and first trifoliate leaf stages of soybean. Total weed dry matter (TDM), weed plant volume, and percent soybean yield loss were arbitrarily selected as a base for determining the CI …

Predicting Biomass Partitioning To Root Versus Shoot In Corn And Velvetleaf (Abutilon Theophrasti), Kimberly D. Bonifas, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Knowledge of how plants will partition their new biomass will aid in understanding competition between crops and weeds. This study determined if the amount of biomass partitioned to the root versus the shoot can be predicted from tissue carbon [C] and nitrogen [N] concentrations and the daily gain in C (G_C) and N (G_N) for each unit shoot and root biomass, respectively. Pots measuring 28 cm diameter and 60 cm deep were embedded in the ground, and each contained one plant of either corn or velvetleaf. Each plant received one of three nitrogen treatments: 0, 1, …