Life Sciences Commons^™

Remote Estimation Of Nitrogen And Chlorophyll Contents In Maize At Leaf And Canopy Levels, Michael Schlemmer, Anatoly A. Gitelson, James S. Schepers, Richard B. Ferguson, Y. Peng, J. Shanahan, Donald Rundquist

Department of Agronomy and Horticulture: Faculty Publications

Leaf and canopy nitrogen (N) status relates strongly to leaf and canopy chlorophyll (Chl) content. Remote sensing is a tool that has the potential to assess N content at leaf, plant, field, regional and global scales. In this study, remote sensing techniques were applied to estimate N and Chl contents of irrigated maize (Zea mays L.) fertilized at five N rates. Leaf N and Chl contents were determined using the red-edge chlorophyll index with R2 of 0.74 and 0.94, respectively. Results showed that at the canopy level, Chl and N contents can be accurately retrieved using green and red-edge Chl …

Optimal Copper Supply Is Required For Normal Plant Iron Deficiency Responses, Brian M. Waters, Laura C. Armbrust

Department of Agronomy and Horticulture: Faculty Publications

Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. Understanding crosstalk between Fe and Cu nutrition could lead to strategies for improved growth on soils with low or excess metals, with implications for agriculture and phytoremediation. Here, we show that Cu and Fe nutrition interact to increase or decrease Fe and/or Cu accumulation in leaves and Fe uptake processes. Leaf Cu concentration increased under low Fe supply, while high Cu lowered leaf Fe concentration. Ferric reductase activity, an indicator of Fe demand, was inhibited at insufficient or high Cu supply. Surprisingly, plants grown without Fe were more susceptible …

Positioning An Innovative Flame-Weeding Technology Into Crop Production, Strahinja V. Stepanovic

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

Propane flaming has a potential to be utilized for effective PRE and POST weed control in both organic and conventional farming systems. Field studies were conducted at the Haskell Agricultural Laboratory of the University of Nebraska in 2010, 2011, and 2012 to: (1) describe dose–response curves for propane when flaming selected weed species at different growth stages, (2) determine corn and soybean tolerance to single and repeated flaming by utilizing the equipment designed to selectively flame weeds in row crops with torches positioned parallel to the crop row, and (3) determine the effectiveness of flaming and cultivation for weed control …

Nebraska Variety And Hybrid Tests: Spring Seed Guide - 2014, Teshome Regassa, Dipak Santra, Charles A. Shapiro, Greg Kruger, Bruce Anderson

Department of Agronomy and Horticulture: Faculty Publications

Corn Hybrid Tests Summary...........3–6

Growing Degree Days and Precipitation by County Charts...........7

Corn Tables 2013 A–F.............8–11

Test Location Map.......................... 11

Corn Hybrid Tests........................12–16

Soybean Variety Tests Summary.....................17–18

Soybean Tables 2013 A–F......19–21

Soybean Variety Tests............22–23

Sunflower Variety Tests......24–28

Pea Variety Test......29

Proso Millet Variety Test .... 30

Economic Impact Assessment Of Sorghum, Millet And Other Grains Crsp: Sorghum And Millet Germplasm Development Research, Timothy J. Dalton, Yacob A. Zereyesus

INTSORMIL Scientific Publications

As a result of the offsetting effect of a rise in productivity and decline in harvested area, the world sorghum production (tonnes) has been on a horizontal trend. The combined effect of a decline in area harvested and a rise in yield productivity have resulted in an overall increase in world millet production (tonnes) trend.

During the last three decades, significant numbers of breeding lines, parental stocks, germplasm and cultivars have been released through INTSORMIL/host countries collaboration around the world. Some of the remarkable breeding success stories include the release of the first hybrid sorghum Hageen Dura (HD-1) and Striga …

Biology And Control Of Common Purslane (Portulaca Oleracea L.), Christopher A. Proctor

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

Common purslane (Portulaca oleracea L.) is a summer annual with wide geographic and environmental distribution. Purslane is typically regarded as a weed in North America, but it is consumed as a vegetable in many parts of the world. One of the characteristics that make purslane difficult to control as a weed is its ability to vegetatively reproduce. Severed sections of purslane stem containing a node will produce adventitious roots from the cut end of the stem. Isoxaben and simazine were the only two effective preemergence herbicides for controlling purslane in our studies when applied at maximum or one-half maximum …

High Yield Soybean Management: Planting Practices, Nutrient Supply, And Growth Modification, Evan Sonderegger

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

Growers are constantly seeking ways to improve yield in soybean [Glycine max (L.) Merr.]. There has been much interest in the use of selected alternative practices to maximize soybean yield. These practices include planting soybean at higher than recommended seeding rates, planting soybean in narrow rows, breaking apical dominance to induce branching, application of strobilurin fungicides prophylactically to minimize disease and extend the seed filling period, the use of N fertilizer both in furrow and foliar applied, and the use of seed treatments to promote early stand establishment and health. Field studies were conducted at the University of Nebraska …

University Awarded $13.7m Competitive Grant To Support Research On Sorghum And Millet And Decrease Hunger In Africa, Greg Tammen

INTSORMIL Impacts and Bulletins

The U.S. Agency for International Development, or USAID, has announced that Kansas State University is the recipient of a $13.7 million grant from the agency to help end poverty and increase food supplies in semiarid Africa. The award was made under Feed the Future, the U.S. government's global hunger and food security initiative.

The five-year grant establishes the Feed the Future Innovation Lab for Collaborative Research on Sorghum and Millet at Kansas State University. With it, the university will serve as the nation's leading center for international sorghum and millet research, as well as a key component in Feed the …

Remote Sensing Of Green Leaf Area Index In Maize And Soybean: From Close-Range To Satellite, Anthony L. Nguy-Robertson

School of Natural Resources: Dissertations, Theses, and Student Research

This dissertation seeks to explore alternative methodologies for estimating green leaf area index (LAI) and crop developmental stages. Specifically this research [1] developed an approach for creating a Moderate Resolution Imaging Spectroradiometer (MODIS) high spatial resolution product for estimating green LAI on the base of data collected using two different close-range sensors. It was determined that the vegetation indices (VIs) Wide Dynamic Range Vegetation Index (WDRVI) and Enhanced Vegetation Index 2 (EVI2) were capable of accurate estimation of green LAI from MODIS 250 m data using models developed from hyperspectral (RMSE < 0.69 m² m^-2; CV < 33%) or multispectral sensors (RMSE < 0.69 m² m^-2; …

Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Conserved non-coding sequences (CNS) are islands of non-coding sequence that, like protein coding exons, show less divergence in sequence between related species than functionless DNA. Several CNSs have been demonstrated experimentally to function as cis-regulatory regions. However, the specific functions of most CNSs remain unknown. Previous searches for CNS in plants have either anchored on exons and only identified nearby sequences or required years of painstaking manual annotation. Here we present an open source tool that can accurately identify CNSs between any two related species with sequenced genomes, including both those immediately adjacent to exons and distal sequences separated by …

Rate Of Shattercane × Sorghum Hybridization In Situ, Jared J. Schmidt, Jeffrey F. Pedersen, Mark L. Bernards, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Cultivated sorghum [Sorghum bicolor (L.) Moench subsp. bicolor] can interbreed with a feral weedy relative shattercane [S. bicolor nothosubsp. drummondii (Steud.) de Wet ex Davidse]. Traits introduced from cultivated sorghum could contribute to the invasiveness of a shattercane population. An experiment was conducted to determine the potential for pollenmediated gene flow from grain sorghum to shattercane. Shattercane with juicy midrib (dd) was planted in soybean [Glycine max (L.) Merr.] fields during 2 yr in concentric arcs at varying distances from a 0.39 ha sorghum pollen source with dry midrib (DD). The arcs …

2013 Fall Seed Guide, Teshome Regassa, P. Stephen Baenziger, Greg Kruger, Dipak Santra

Department of Agronomy and Horticulture: Faculty Publications

Nebraska Winter Wheat Variety Tests

Locations for Winter Wheat

Winter Wheat Characteristics

Alfalfa Variety Tests

Cool Season Grasses

Winter Barley Variety Tests

Triticale

NCIA Seed Book

Application Carrier Volume: A Comprehensive Evaluation Of An Ultra-Low Volume Sprayer Compared To A Conventional Sprayer For Row-Crop And Turfgrass Production Systems, Jason Connor Ferguson

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

An Ultra-Low Volume (ULV) sprayer was developed to decrease carrier volume required for pesticide applications in row and turfgrass cropping systems. The ULV sprayer can make spray applications at or below 19 L ha^-1, which is far lower than a conventional sprayer in row crop or turfgrass production systems. Field studies were conducted at the University of Nebraska West Central Research and Extension Center Dryland Farm near North Platte, NE and the John Seaton Anderson Turfgrass Research Facility near Mead, NE to compare the ULV sprayer to a conventional sprayer. Studies were conducted to compare the two sprayers …

Agricultural Development In The Northern Savannah Of Ghana, Tara N. Wood

Doctor of Plant Health Program: Dissertations and Student Research

Since declaring independence in 1957, the Republic of Ghana has become a stable constitutional democracy. Ghana’s economy has grown substantially over the past decade, yet remains primarily agrarian, accounting for 50% of the total employment and 25% of the country’s Gross Domestic Product. Smallholder rain-fed farming using rudimentary technologies dominates the agricultural sector accounting for 80% of total agricultural production. Approximately 90% of smallholder farms are less than two hectares in size, and produce a diversity of crops. The major crops cultivated in Ghana include numerous cereal, root and tuber, leguminous, fruit, vegetable and industrial crops. Maize is the most …

Response Of Nebraska Horseweed (Conyza Canadensis) Populations To Dicamba, Roberto Crespo, Mark L. Bernards, Greg Kruger, Donald Lee, Robert Wilson Jr.

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

Dicamba-resistant soybeans are being developed to provide an additional herbicide mechanism-of-action for postemergence weed control in soybean. Numerous broadleaf species, including horseweed, have evolved resistance to glyphosate. It is anticipated that dicamba will be used by farmers as a primary tool to manage these weeds. Studying and understanding variability in horseweed response to dicamba will aid in developing appropriate risk management strategies to extend the utility of the dicamba-resistance technology. Horseweed plants from ten Nebraska populations were treated with one of nine doses of dicamba in greenhouse experiments. At 28 days after treatment (DAT) visual injury estimations were made and …

Guia Tecnica Para La Produccion Artesanal De Semilla De Variedades De Polinizacion Libre De Sorgo En America Central, René Clará Valencia

INTSORMIL Scientific Publications

La producción de semilla artesanal de sorgo es un complemento en la producción y uso de semilla certificada y tiene como objetivo el de atender a los agricultores que por diversas razones no acceden a la semilla certificada, pero son sujetos potenciales de producción y desarrollo del cultivo de sorgo. En términos generales son los agricultores de menos recursos, que representan la mayoría de productores de sorgo en América Central, los que se ven limitados a la utilización de las variedades mejoradas. Debemos de meditar sobre la utilización de las variedades mejoradas de polinización libre y probablemente el poco acceso …

Genetic Mapping And Confirmation Of Quantitative Trait Loci For Seed Protein And Oil Contents And Seed Weight In Soybean, Safiullah M. Pathan, Tri Vuong, Kerry Clark, Jeong-Dong Lee, J. Grover Shannon, Craig A. Roberts, Mark R. Ellersieck, Joseph W. Burton, P. B. Cregan, David L. Hyten, Henry T. Nguyen, David A. Sleper

Department of Agronomy and Horticulture: Faculty Publications

Demand for soybean [Glycine max (L.) Merr.] meal has increased worldwide and soybean importers often offer premiums for soybean containing higher contents of protein and oil. Objectives were to detect quantitative trait loci (QTL) associated with soybean seed protein, oil, and seed weight in a soybean mapping population and confirm detected QTL across genetic backgrounds and environments. Two populations of 216 and 156 recombinant inbred lines were developed from Magellan × PI 438489B and Magellan × PI 567516C crosses, respectively, and grown in two Missouri environments in 2008. More than 900 simple sequence repeat (SSR) and single nucleotide polymorphism …

Resource Allocation For Maximizing Prediction Accuracy And Genetic Gain Of Genomic Selection In Plant Breeding: A Simulation Experiment, Aaron Lorenz

Department of Agronomy and Horticulture: Faculty Publications

Allocating resources between population size and replication affects both genetic gain through phenotypic selection and quantitative trait loci detection power and effect estimation accuracy for marker-assisted selection (MAS). It is well known that because alleles are replicated across individuals in quantitative trait loci mapping and MAS, more resources should be allocated to increasing population size compared with phenotypic selection. Genomic selection is a form of MAS using all marker information simultaneously to predict individual genetic values for complex traits and has widely been found superior to MAS. No studies have explicitly investigated how resource allocation decisions affect success of genomic …

Evaluation Of Public Sweet Sorghum A-Lines For Use In Hybrid Production, Jeffrey F. Pedersen, Scott E. Sattler, William F. Anderson

Department of Agronomy and Horticulture: Faculty Publications

A fundamental need for commercialization of sweet sorghum [Sorghum bicolor (L.) Moench] as a bioenergy crop is an adequate seed supply, which will require development of hybrid varieties using dwarf seed-parent lines. A set of six public sweet sorghum A-lines (Dwarf Kansas Sourless, KS9, N36, N38, N39, and N4692) were crossed with a set of six public sweet sorghum cultivars (Brawley, Kansas Collier, Dale, Sugar Drip, Waconia, and Wray). Grain, fiber, and sugar yields were determined, and conversion formulas were applied to estimate ethanol yields. Hybrids were grown in fields at Ithaca, NE, USA, in 1983– 1984 fertilized with …

The Clubroot Pathogen (Plasmodiophora Brassicae) Influences Auxin Signaling To Regulate Auxin Homeostasis In Arabidopsis, Linda Jahn, Stefanie Mucha, Sabine Bergmann, Cornelia Horn, Paul E. Staswick, Bianka Steffens, Johannes Siemens, Jutta Ludwig-Müller

Department of Agronomy and Horticulture: Faculty Publications

The clubroot disease, caused by the obligate biotrophic protist Plasmodiophora brassicae, affects cruciferous crops worldwide. It is characterized by root swellings as symptoms, which are dependent on the alteration of auxin and cytokinin metabolism. Here, we describe that two different classes of auxin receptors, the TIR family and the auxin binding protein 1 (ABP1) in Arabidopsis thaliana are transcriptionally upregulated upon gall formation. Mutations in the TIR family resulted in more susceptible reactions to the root pathogen. As target genes for the different pathways we have investigated the transcriptional regulation of selected transcriptional repressors (Aux/IAA) and transcription …

Sub1a-Mediated Submergence Tolerance Response In Rice Involves Differential Regulation Of The Brassinosteroid Pathway, Aaron J. Schmitz, Jing J. Folsom, Yusuke Jikamaru, Pamela C. Ronald, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Submergence 1A (SUB1A), is an ethylene response factor (ERF) that confers submergence tolerance in rice (Oryza sativa) via limiting shoot elongation during the inundation period. SUB1A has been proposed to restrict shoot growth by modulating gibberellic acid (GA) signaling.

Our transcriptome analysis indicated that SUB1A differentially regulates genes associated with brassinosteroid (BR) synthesis during submergence. Consistent with the gene expression data, the SUB1A genotype had higher brassinosteroid levels after submergence compared to the intolerant genotype. Tolerance to submergence can be activated in the intolerant genotype by pretreatment with exogenous brassinolide, which results in restricted shoot elongation …

Unleashing The Potential Of The Root Hair Cell As A Single Plant Cell Type Model In Root Systems Biology, Zhenzhen Qiao, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Plant root is an organ composed of multiple cell types with different functions.This multicellular complexity limits our understanding of root biology because -omics studies performed at the level of the entire root reflect the average responses of all cells composing the organ. To overcome this difficulty and allow a more comprehensive understanding of root cell biology, an approach is needed that would focus on one single cell type in the plant root. Because of its biological functions (i.e., uptake of water and various nutrients; primary site of infection by nitrogen-fixing bacteria in legumes), the root hair cell is an attractive …

Immunodetection Of Triticum Mosaic Virus By Das- And Dac-Elisa Using Antibodies Produced Against Coat Protein Expressed In Escherichia Coli: Potential For High-Throughput Diagnostic Methods, Satyanarayana Tatineni, Gautam Sarath, Dallas Seifers, Roy C. French

Department of Agronomy and Horticulture: Faculty Publications

Triticum mosaic virus (TriMV), an economically important virus infecting wheat in the Great Plains region of the USA, is the type species of the Poacevirus genus in the family Potyviridae. Sensitive and high-throughput serology-based detection methods are crucial for the management of TriMV and germplasm screening in wheat breeding programs. In this study, TriMV coat protein (CP) was expressed in Escherichia coli, and polyclonal antibodies were generated against purified soluble native form recombinant CP (rCP) in rabbits. Specificity and sensitivity of resulting antibodies were tested in Western immuno-blot and enzyme-linked immunosorbent assays (ELISA). In direct antigen coating (DAC)-ELISA, …

Enzyme Activity In Wheat Breeding Lines Derived From Matings Of Low Polyphenol Oxidase Parents, Somrudee Nilthong, Robert A. Graybosch, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Polyphenol oxidase (PPO) in grain plays a major role in time-dependent discoloration of wheat (Triticum aestivum L.) products, especially fresh noodles. Breeding wheat cultivars with low or nil PPO activity can reduce undesirable product darkening. The low PPO line PI 117635 was crossed to two low PPO wheats, IDO580 and ‘IDO377s’, to determine whether matings between wheats with low levels of grain PPO would result in complementation, such that lines with still lower or nil PPO would be generated. Progeny in a population derived from PI 117635/ IDO580 displayed no variation in PPO activity. In the F_3:4 populations …

Soil Sorptivity Enhancement With Crop Residue Accumulation In Semiarid Dryland No-Till Agroecosystems, T.M. Shaver, G. A. Peterson, Laj R. Ahuja, D.G. Westfall

Department of Agronomy and Horticulture: Faculty Publications

Water capture and precipitation use efficiency are of great importance in dryland cropping systems because the world's dependence on food produced in dryland areas continues to increase. Growing season evapotranspiration potential greatly exceeds growing season precipitation rates in dryland areas, creating a water deficit for crops. Management practices that positively impact soil physical properties increase the potential for soils to capture water. One way to assess the ability of soils to capture water is through the measurement of sorptivity. Sorptivity is defined as the cumulative infiltration proportionality constant and is governed by surface soil physical properties such as texture, degree …

Arbuscular Mycorrhizal Fungi Differ In Their Ability To Regulate The Expression Of Phosphate Transporters In Maize (Zea Mays L.), Hui Tian, Rhae A. Drijber, Xiaolin Li, Daniel N. Miller, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Previous studies have found that some phosphate (Pi) starvation inducible transporter genes are downregulated and arbuscular mycorrhizal (AM) inducible Pi transporter genes are upregulated in maize roots associated with the fungus Glomus intraradices. However, little is known about the functional diversity of different AM fungal species in influencing the expression of Pi transporters in maize roots. Here, we studied the expression of two Pi transporter genes ZEAma:Pht1;3 (Pi starvation inducible) and ZEAma:Pht1;6 (AM inducible) in maize root colonized by different AM fungal inoculants. Non-mycorrhizal maize, maize colonized by Glomus deserticola (CA113), Glomus intraradices (IA506), Glomus mosseae (CA201), Gigaspora gigantea …

Functional Characterization Of Cinnamyl Alcohol Dehydrogenase And Caffeic Acid O-Methyltransferase In Brachypodium Distachyon, Gina M. Trabucco, Dominick A. Matos, Scott J. Lee, Aaron J. Saathoff, Henry D. Priest, Todd C. Mockler, Gautam Sarath, Samuel P. Hazen

Department of Agronomy and Horticulture: Faculty Publications

Background: Lignin is a significant barrier in the conversion of plant biomass to bioethanol. Cinnamyl alcohol dehydrogenase (CAD) and caffeic acid O-methyltransferase (COMT) catalyze key steps in the pathway of lignin monomer biosynthesis. Brown midrib mutants in Zea mays and Sorghum bicolor with impaired CAD or COMT activity have attracted considerable agronomic interest for their altered lignin composition and improved digestibility. Here, we identified and functionally characterized candidate genes encoding CAD and COMT enzymes in the grass model species Brachypodium distachyon with the aim of improving crops for efficient biofuel production.

Results: We developed transgenic plants overexpressing artificial microRNA designed …

Complete Plastid Genomes From Ophioglossum Californicum, Psilotum Nudum, And Equisetum Hyemale Reveal An Ancestral Land Plant Genome Structure And Resolve The Position Of Equisetales Among Monilophytes, Felix Grewe, Wenhu Guo, Emily A. Gubbels, A Katie Hansen, Jeffrey P. Mower

Department of Agronomy and Horticulture: Faculty Publications

Background: Plastid genome structure and content is remarkably conserved in land plants. This widespread conservation has facilitated taxon-rich phylogenetic analyses that have resolved organismal relationships among many land plant groups. However, the relationships among major fern lineages, especially the placement of Equisetales, remain enigmatic.

Results: In order to understand the evolution of plastid genomes and to establish phylogenetic relationships among ferns, we sequenced the plastid genomes from three early diverging species: Equisetum hyemale (Equisetales), Ophioglossum californicum (Ophioglossales), and Psilotum nudum (Psilotales). A comparison of fern plastid genomes showed that some lineages have retained inverted repeat (IR) boundaries originating …

Erratum To: Identification And Characterization Of Four Missense Mutations In Brown Midrib12 (Bmr12), The Caffeic Acid O-Methyltranferase (Comt) Of Sorghum, Scott E. Sattler, Nathan A. Palmer, Ana Saballos, Ann M. Greene, Zhanguo Xin, Gautam Sarath, Wilfred Vermerris, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

The original version of this article unfortunately contained some mistakes. The name of the enzyme “Caffeic O-methyltransferase” should be read as “Caffeic acid O-Methyltranferase” throughout the paper, including the title.

On Table 2, the fifth column should have been captured as part of the sub-heading “Unpretreated”. The corrected version is shown on the next page.

Table 2 Variation in Klason lignin content and glucose yields obtained after enzymatic saccharification at 50 °C at 60 FPU/ g cellulase of native (unpretreated) stover after 4, 20, and 96 h, and of pretreated stover after 24 h

Transcriptome Analysis Of Two Buffalograss Cultivars, Michael Wachholtz, Tiffany Heng-Moss, Paul Twigg, Lisa Baird, Guoqing Lu, Keenan Amundsen

Department of Agronomy and Horticulture: Faculty Publications

Background: Buffalograss [Buchloë dactyloides (Nutt.) Engel. syn. Bouteloua dactyloides (Nutt.) Columbus] is a United States native turfgrass species that requires less irrigation, fungicides and pesticides compared to more commonly used turfgrass species. In areas where water is limited, interest in this grass species for lawns is increasing. While several buffalograss cultivars have been developed through buffalograss breeding, the timeframe for new cultivar development is long and is limited by a lack of useful genetic resources. Two high throughput next-generation sequencing techniques were used to increase the genomic resources available for buffalograss.

Results: Total RNA was extracted and …