Plant Biology Commons^™

Toward Sustainable Production Of Value-Added Bioenergy And Industrial Oils In Oilseed And Biomass Feedstocks, Kiyoul Park, Sanju A. Sanjaya, Truyen Quach, Edgar B. Cahoon

Center for Plant Science Innovation: Faculty Publications

Plant fatty acids are used forfood, feed, fuel, and industrial materials. Structurally and chemically diverse fatty acids, referred to as unusual or specialized fatty acids, are found in the seed oils of diverse plant species. Many unusual fatty acids have potential use as alternative and renewable sources of biofuels and biobased industrial feedstocks due to their variant structures' physical or functional properties. Oils enriched in these fatty acids can increase the value of oilseed crops and provide co-products that can be readily extracted from lignocellulosic materials in biomass crops. Here, we describe recent progress in strategies for enhancement of oil …

Critical Time For Weed Removal In Corn As Influenced By Planting Pattern And Pre Herbicides, Dejan Nedeljkovic, Stevan Knezevic, Dragana Bozic, Sava Vrbnicanin

Department of Agronomy and Horticulture: Faculty Publications

Determining the critical time for weed removal (CTWR) is essential for the development of an integrated weed management plan. Therefore, field experiments were conducted to evaluate the effects of two planting patterns (standard and twin-row) with and without PRE-applied herbicides on CTWR in corn. Experiments were laid out in a split-plot arrangement with two main plots: (i) standard row planting (SRP) that is 70 cm wide, and (ii) twin-row planting (TRP) with 50 cm distance between each set of double rows. Each main plot was divided into two sub-plots (with and without PRE herbicides). The sub-sub-plots consisted of seven weed …

Disruption Of Long-Chain Base Hydroxylation Alters Growth And Impacts Sphingolipid Synthesis In Physcomitrella Patens, Abraham R. Steinberger, William Oscar Merino, Rebecca E. Cahoon, Edgar B. Cahoon, Daniel V. Lynch

Center for Plant Science Innovation: Faculty Publications

Sphingolipids have roles as membrane structural components and as bioactive molecules in plants. In Physcomitrella patens, 4-hydroxysphinganine (phytosphingosine, t18:0) is the predominant sphingolipid long-chain base (LCB). To assess the functional significance of t18:0, CRISPR-Cas9 mutagenesis was used to generate mutant lines lacking the sole SPHINGOID BASE HYDROXYLASE (SBH) gene encoding the hydroxylase responsible for converting sphinganine (d18:0) to t18:0. Total sphingolipid content in sbh protonemata was 2.4-fold higher than in wild-type. Modest changes in glycosyl inositolphosphorylceramide (GIPC) glycosylation patterns occurred. Sphingolipidomic analyses of mutants lacking t18:0 indicated modest alterations in acyl-chain pairing with d18:0 in GIPCs and ceramides, but dramatic …

Sweet Sorghum Genotypes Tolerant And Sensitive To Nitrogen Stress Select Distinct Root Endosphere And Rhizosphere Bacterial Communities, Lucas Dantas Lopes, Yen Ning Chai, Ellen L. Marsh, John F. Rajewski, Ismail Dweikat, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

The belowground microbiomes have many beneficial functions that assist plant growth, including nutrient cycling, acquisition and transport, as well as alleviation of stresses caused by nutrient limitations such as nitrogen (N). Here we analyzed the root endosphere, rhizosphere and soil bacterial communities of seven sweet sorghum genotypes differing in sensitivity to N-stress. Sorghum genotypes were grown in fields with no (low-N) or sufficient (high-N) N. The dry shoot weight ratio (low-N/high-N) was used to determine N-stress sensitivity. Our hypothesis was that genotypes tolerant and sensitive to N-stress select distinct bacterial communities. The endosphere and rhizosphere bacterial community structure were significantly …

Meta-Analysis Identifies Pleiotropic Loci Controlling Phenotypic Trade-Offs In Sorghum, Ravi V. Mural, Marcin Grzybowski, Miao Chenyong, Alyssa Damke, Sirjan Sapkota, Richard E. Boyles, Maria G. Salas Fernandez, Patrick S. Schnable, Brandi Sigmon, Stephen Kresovich, James C. Schnable

Department of Plant Pathology: Faculty Publications

Community association populations are composed of phenotypically and genetically diverse accessions. Once these populations are genotyped, the resulting marker data can be reused by different groups investigating the genetic basis of different traits. Because the same genotypes are observed and scored for a wide range of traits in different environments, these populations represent a unique resource to investigate pleiotropy. Here, we assembled a set of 234 separate trait datasets for the Sorghum Association Panel, a group of 406 sorghum genotypes widely employed by the sorghum genetics community. Comparison of genome-wide association studies (GWAS) conducted with two independently generated marker sets …

Rhizosphere Microbiomes In A Historical Maize-Soybean Rotation System Respond To Host Species And Nitrogen Fertilization At The Genus And Subgenus Levels, Michael A. Meier, Martha G. Lopez-Guerrero, Ming Guo, Marty Schmer, Josh Herr, James Schnable, James R. Alfano, Jinliang Yang

Department of Agronomy and Horticulture: Faculty Publications

Root-associated microbes are key players in plant health, disease resistance, and nitrogen (N) use efficiency. It remains largely unclear how the interplay of biological and environmental factors affects rhizobiome dynamics in agricultural systems. In this study, we quantified the composition of rhizosphere and bulk soil microbial communities associated with maize (Zea mays L.) and soybean (Glycine max L.) in a long-term crop rotation study under conventional fertilization and low-N regimes. Over two growing seasons, we evaluated the effects of environmental conditions and several treatment factors on the abundance of rhizosphere- and soil-colonizing microbial taxa. Time of sampling, host plant species, …

Using Thermal Imaging To Measure Water Stress In Creeping Bentgrass Putting Greens, Joseph G. Foral Jr.

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

Thermal imaging is a developing tool that can help turf managers reduce water consumption and improve irrigation scheduling, but in-depth studies are needed to maximize this potential. This study evaluated the ability of thermal imaging to identify water stress in a creeping bentgrass (Agrostis stolonifera ‘007’) putting green. Water use and canopy temperature (T_c) were measured for plots subjected to three levels of measured water replacement (full, half, and none) to evaluate changes over a range of soil water potentials (SWP). Water use was consistent across the irrigation treatments up to several days before observed wilt …

Morphophysiological And Molecular Characterization Of Millet (Panicum Miliaceum L.) Varieties For Crop Improvement In Western Europe, Massimo Vischi, Nicola Zorzin, Maria Bernhart, Johanna Winkler, Dipak Santra, Carla Pappalardo, Stefano Marchetti

Department of Agronomy and Horticulture: Faculty Publications

Background

Global warming and issues in favour of a more sustainable agriculture suggest a reconsideration of minor cereals in European agrosystems. Compared to other summer crops, proso millet has a remarkable drought resistance and could be used to improve crop rotation and biodiversity. Proso millet is also increasingly sought by industry to produce novel foods such as those designed for celiac patients. In this study, a thorough characterization of 11, commercially available, proso millet (Panicum milliaceum L.) varieties was carried out as a preliminary step for crop reintroduction and breeding in Western Europe.

Methods

The cultivars under evaluation were …

Improved Taste And Texture In Novel Popcorn Varieties Compared To Conventional Lines, Leandra Parsons, Oscar Rodriguez, David R. Holding

Department of Agronomy and Horticulture: Faculty Publications

Abstract Quality Protein Popcorn (QPP) varieties were bred out of a unique germplasm pool derived from Quality Protein dent Maize and conventional popcorn lines. To identify and compare distinctive characteristics within this population, a new sensory method was employed that coupled hedonic numeric rankings of common sensory traits appearance, aroma, texture, and taste with an “overall likability” score while requiring the selection of specific descriptors for taste and texture. Participants tasted six popcorn cultivars, rated each sample based on sensory factors, and offered specific descriptors for taste and texture. This sensory method identified two QPP hybrids with higher overall likability …

Coleoptile Length Comparison Of Three Winter Small Grain Cereals Adapted To The Great Plains, M. Alam, M. Kashif, Amanda Easterly, F. Wang, J. D. Boehm Jr., P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Successful crop stand establishment is critical to realize high yield potential, which is dependent on depth of seed placement to access soil moisture. The coleoptile determines sowing depth by its length and ability to emerge from depth. This study was conducted to assess coleoptile length among three sets of three Great Plains winter small grain cereals—wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and triticale (X triticosecale Wittm.)—and to evaluate the effect of the Rht-B1b dwarfing allele on coleoptile length in wheat and triticale. Fifty seeds of each genotype were sown in wet germination paper in two …

Estimation Of Household Smoke-Exposure Risk Using Demographic And Health Survey (Dhs) Data, Mazbahul G. Ahamad, Fahian Tanin

Department of Agronomy and Horticulture: Faculty Publications

We introduce Stata and R codes to estimate the household smoke-exposure risk (SER) variable using cooking fuel- and cooking place-related information obtained from country-level demographic and health survey (DHS) data. Two categories of cooking fuels (smoke-producing and non-smoke producing fuels) and two categories of cooking places (indoor and outdoor) are used to estimate the household SER. Finally, household SER is classified into four levels of risk: high (cooking indoor using smoke-producing fuels), medium (cooking outdoor using smoke-producing fuels), low (cooking indoor using non-smoke-producing fuels), and very low (cooking outdoor using non-smoke-producing fuels). An example of a household SER calculation using …

Quantitative Trait Loci Controlling Agronomic And Biochemical Traits In Cannabis Sativa, Patrick Woods, Brian J. Campbell, Timothy J. Nicodemus, Edgar B. Cahoon, Jack L. Mullen, John K. Mckay

Center for Plant Science Innovation: Faculty Publications

Understanding the genetic basis of complex traits is a fundamental goal of evolutionary genetics. Yet, the genetics controlling complex traits in many important species such as hemp (Cannabis sativa) remain poorly investigated. Because hemp’s change in legal status with the 2014 and 2018 U.S. Federal Farm Bills, interest in the genetics controlling its numerous agriculturally important traits has steadily increased. To better understand the genetics of agriculturally important traits in hemp, we developed an F2 population by crossing two phenotypically distinct hemp cultivars (Carmagnola and USO31). Using whole-genome sequencing, we mapped quantitative trait loci (QTL) associated with variation …

Techniques To Improve The Volume, Texture And Nutritional Quality Of Gluten-Free Bread, Zachary Christman

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

This article highlights the use of soy flour to improve the protein and fiber of gluten free bread. Also, the use of an extrusion process on soybean and corn flour blends improves the volume and texture of the bread. A full listing of the ingredients and method for production of higher quality gluten free bread is included.

Center For Grassland Studies, May 2021

Center for Grassland Studies: Newsletters

Contents

Prescribed Burn Associations by Brian Teeter

Center for Grassland Studies Policy Advisory Committee

Director's Column by Walt Schact (Interim Director)

Looking for a Career in Conservation – How to Apply in USAJOBS for NRCS Positions by Mary Reece

Monitoring Sandhills Rangelands: A Key Step in Understanding Plant Community Dynamics by Mitch Stephenson

Development of Novel Plant Fluorescence Based Techniques for Remote Assessment of Grasslands and Pastures Health and Resilience by Anastasios Mazis

UNL PGA Golf Management Alumni Among Nebraska Section Award Winners by Brad Goetsch

Nebraska’s Grassland Legacy by Walt Schacht

Nebraska Grazing Conference: Save the Date, August 9-11, …

Production, Evaluation, And Selection Of Elite Quality Protein Popcorn (Qpp) Hybrids, Leandra Marshall Parsons

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

In 2017, twelve Quality Protein Popcorn (QPP) inbred lines were developed and selected as premier dent by popcorn crosses fit for hybridization and testing. These QPP inbred lines were derived from specific Quality Protein dent Maize (QPM) by ConAgra Brands® popcorn line crosses to produce high lysine, vitreous popcorn lines capable of near-equal popping characteristics compared to the original popcorn parents. The QPP hybridization project commenced in the summer of 2018 utilizing these 12 inbred QPP lines and crossing them in a full diallel. Since then, the production of QPP hybrids has employed a diverse set of selection factors evaluating …

The Effect Of Anionic Surfactants On Herbicide Mixtures And Solutions, Ely Daniel Anderson

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

Herbicide mixtures are popular for farmers to delay the evolution of herbicide-resistant biotypes from occurring and control existing herbicide-resistant weeds. Glufosinate is a contact herbicide that has been observed as a mixture partner with many herbicides. In many cases, antagonistic interactions have occurred when using glufosinate in mixture with other herbicides. The antagonistic interactions have resulted in applications with incomplete weed control. Adjuvants have been known to impact an herbicide application by increasing herbicide penetration, spreadability, and efficacy. Adjuvants added to glufosinate mixtures can impact spray applications and increase weed control. The objectives of this research were: (1) investigate the …

Origin Of Agricultural Plant Pathogens: Diversity And Pathogenicity Of Rhizoctonia Fungi Associated With Native Prairie Grasses In The Sandhills Of Nebraska, Srikanth Kodati, Anthony O. Adesemoye, Gary Y. Yuen, Jerry Volesky, Sydney E. Everhart

Department of Plant Pathology: Faculty Publications

The Sandhills of Nebraska is a complex ecosystem, covering 50,000 km² in central and western Nebraska and predominantly of virgin grassland. Grasslands are the most widespread vegetation in the U.S. and once dominated regions are currently cultivated croplands, so it stands to reason that some of the current plant pathogens of cultivated crops originated from grasslands, particularly soilborne plant pathogens. The anamorphic genus Rhizoctonia includes genetically diverse organisms that are known to be necrotrophic fungal pathogens, saprophytes, mycorrhiza of orchids, and biocontrol agents. This study aimed to evaluate the diversity of Rhizoctonia spp. on four native grasses in the …

Phenotypic Plasticity Of Diverse Sorghum Varieties In Response To Nitrogen Deficit Stress, Mackenzie Zwiener

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

The movement of nutrients from old vegetative tissue to young leaves and reproductive organs is known as senescence. Senescence can be influenced by the environment of a plant, such as, drought, heat, and nutrient stress. These environmental stressors can also influence canopy architecture. Crop canopy consists of several traits including: leaf number, angle, length and width. Past research in crops like maize and rice have shown significant influences of more erect leaves, including, the ability for increased planting density, which optimizes light interception and increases yield. In a field trial of a sorghum association panel including 345 different sorghum varieties …

An Ancient, Light-Dependent Hydrocarbon-Forming Enzyme, Ananya Mukherjee

Center for Plant Science Innovation: Faculty Publications

No abstract provided.

Changes In Subcellular Localization Of Host Proteins Induced By Plant Viruses, Rosalba Rodriguez-Pena, Kaoutar El Mounadi, Hernan Garcia-Ruiz

Department of Plant Pathology: Faculty Publications

Viruses are dependent on host factors at all parts of the infection cycle, such as translation, genome replication, encapsidation, and cell-to-cell and systemic movement. RNA viruses replicate their genome in compartments associated with the endoplasmic reticulum, chloroplasts, and mitochondria or peroxisome membranes. In contrast, DNA viruses replicate in the nucleus. Viral infection causes changes in plant gene expression and in the subcellular localization of some host proteins. These changes may support or inhibit virus accumulation and spread. Here, we review host proteins that change their subcellular localization in the presence of a plant virus. The most frequent change is the …

Nozzle Selection And Adjuvant Impact On The Efficacy Of Glyphosate And Ppo-Inhibiting Herbicide Tank-Mixtures, Jesaelen G. Moraes, Thomas R. Butts, Vitor M. Anunciato, Joe D. Luck, Wesley C. Hoffmann, Ulisses R. Antuniassi, Greg R. Kruger

Department of Agronomy and Horticulture: Faculty Publications

PPO-inhibiting herbicides in combination with glyphosate for postemergence applications is a common approach to manage glyphosate- and ALS-inhibitor-resistant weeds. PPO-inhibitors can reduce glyphosate translocation when applied in tank-mixtures, but adjuvants may be used to overcome this effect. Additionally, optimal droplet size may be affected by tank-mixtures of different herbicides and it can be crucial to herbicide efficacy. Field and greenhouse studies were conducted to investigate the impact of nozzle selection and adjuvants on weed control and interactions when applying PPO-inhibitors (fomesafen or lactofen) alone or in tank-mixture with glyphosate to five weed species using six nozzle types. Ultra-coarse droplets were …

The Influence Of Adjuvants On Physical Properties, Droplet-Size, And Efficacy Of Glufosinate And Dicamba Plus Glyphosate Solutions, Estefania Gomiero Polli

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

Adjuvants are used in agriculture to improve herbicide activity or application performance. The addition of adjuvants to herbicide solution can enhance its penetration, wettability, and evaporation rates by altering density, viscosity, contact angle between the droplet and plant surface, and droplet surface tension. Furthermore, those alterations in the physical properties of the herbicide solution can result in changes in the droplet-size distribution that directly impact herbicide efficacy. The adoption of glufosinate-based herbicide programs has increased with the widespread occurrence of glyphosate-resistance (GR) weeds in recent years. Also, tank mixture of dicamba and glyphosate has been largely adopted for broad-spectrum weed …

Maize Nitrogen Management Using Reactive Sensor And Proactive Maize-N Model Via Fertigation, Mohammed Abdulridha Naser

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

Applying a portion of total nitrogen (N) during the growing season has the potential to improve nitrogen use efficiency (NUE) by achieving greater synchrony between N supply and crop N demand, allowing for responsive adjustments to actual field conditions. Three studies from 2017-2019 evaluated using reactive sensor and proactive Maize-N model for determining in-season N requirements via fertigation in corn. The first study evaluated the integration of reactive sensor and proactive Maize-N model for determining the timing and rate of in-season N via fertigation. Overall, reactive and proactive fertigation treatments reduced total N applied by 35 to 65 kg N …

Comparing A Mixed Model Approach To Traditional Stability Estimators For Mapping Genotype By Environment Interactions And Yield Stability In Soybean [Glycine Max (L.) Merr.], Mary M. Happ, George L. Graef, Haichuan Wang, Reka Howard, Luis Posadas, David L. Hyten

Department of Agronomy and Horticulture: Faculty Publications

Identifying genetic loci associated with yield stability has helped plant breeders and geneticists begin to understand the role and influence of genotype by environment (GxE) interactions in soybean [Glycine max (L.) Merr.] productivity, as well as other crops. Quantifying a genotype’s range of performance across testing locations has been developed over decades with dozens of methodologies available. This includes directly modeling GxE interactions as part of an overall model for yield, as well as methods which generate overall yield “stability” values from multi-environment trial data. Correspondence between these methods as it pertains to the outcomes of genome wide association studies …

Soil Erosion Modelling: A Bibliometric Analysis, Nejc Bezak, Matjǎz Mikǒs, Pasquale Borrelli, Christine Alewell, Dinesh Panday, Panos Panagos, 59 Co-Authors

Department of Agronomy and Horticulture: Faculty Publications

Soil erosion can present a major threat to agriculture due to loss of soil, nutrients, and organic carbon. Therefore, soil erosion modelling is one of the steps used to plan suitable soil protection measures and detect erosion hotspots. A bibliometric analysis of this topic can reveal research patterns and soil erosion modelling characteristics that can help identify steps needed to enhance the research conducted in this field. Therefore, a detailed bibliometric analysis, including investigation of collaboration networks and citation patterns, should be conducted. The updated version of the Global Applications of Soil Erosion Modelling Tracker (GASEMT) database contains information about …

Compounds Derived From Bacteria Enhance Marine Diatom Growth, Ananya Mukherjee

Center for Plant Science Innovation: Faculty Publications

No abstract provided.

Mental Model-Based Repeated Multifaceted (Mrm) Intervention Design: A Conceptual Framework For Improving Preventive Health Behaviors And Outcomes, Mazbahul G. Ahamad, Fahian Tanin

Department of Agronomy and Horticulture: Faculty Publications

Objective: Field interventions employed to improve preventive health behaviors and outcomes generally use well established approaches; however, recent studies have reported that health education and promotional interventions have little to no impact on health behaviors, especially in low- and middle-income countries. We aimed to develop a conceptual framework to improve intervention designs that would internalize these concerns and limitations.

Results: We identified three major experimental design- and implementation-related concerns associated with mental models, including the balance between the treatment and control groups, the treatment group’s willingness to adopt suggested behaviors, and the type, length, frequency, intensity, and sequence of treatments. …

Grass Bud Responses To Fire In A Semiarid Savanna System, Quinn A. Hiers, Morgan L. Treadwell, Matthew B. Dickinson, Kathleen L. Kavanagh, Alexandra G. Lodge, Heath D. Starns, Doug R. Tolleson, Dirac Twidwell, Carissa L. Wonkka, William E. Rogers

Department of Agronomy and Horticulture: Faculty Publications

Increasingly, land managers have attempted to use extreme prescribed fire as a method to address woody plant encroachment in savanna ecosystems. The effect that these fires have on herbaceous vegetation is poorly understood. We experimentally examined immediate (<24 hr) bud response of two dominant graminoids, a C₃ caespitose grass, Nassella leucotricha, and a C₄ stoloniferous grass, Hilaria belangeri, following fires of varying energy (J/m² ) in a semiarid savanna in the Edwards Plateau ecoregion of Texas. Treatments included high- and low-energy fires determined by contrasting fuel loading and a no burn (control) treatment. Belowground axillary buds were counted and their activities classified to determine immediate effects …

Effects Of Intraguild Interactions On Anticarsia Gemmatalis And Chrysodeixis Includens Larval Fitness And Behavior In Soybean, Sabrina Ongaratto, Edson Ll Baldin, Thomas E. Hunt, Debora G. Montezano, Emily A. Robinson, Maria C. Dos Santos

Department of Agronomy and Horticulture: Faculty Publications

BACKGROUND: Crop pest management requires an understanding of the complex interactions among species that potentially impact crop yield. In soybean, the velvetbean caterpillar, Anticarsia gemmatalis (Hübner), and the soybean looper, Chrysodeixis includens (Walker), are described as key pests, sharing the same feeding guild. We assessed the intraguild interactions of these species under laboratory conditions. Fitness cost study was conducted to examine the influence of competition on insect development. A video tracking system was used to evaluate behavioral parameters during larval interactions in scenarios with and without food availability. RESULTS: In the fitness cost assay, pupal weight was not significantly affected, …

Microbial Community Field Surveys Reveal Abundant Pseudomonas Population In Sorghum Rhizosphere Composed Of Many Closely Related Phylotypes, Dawn Chiniquy, Elle M. Barnes, Jinglie Zhou, Kyle Hartman, Xiaohui Li, Amy Sheflin, Ellen Marsh, Jessica Prenni, Adam M. Deutschbauer, Daniel P. Schachtman, Susannah G. Tringe

Department of Agronomy and Horticulture: Faculty Publications

While the root-associated microbiome is typically less diverse than the surrounding soil due to both plant selection and microbial competition for plant derived resources, it typically retains considerable complexity, harboring many hundreds of distinct bacterial species. Here, we report a time-dependent deviation from this trend in the rhizospheres of field grown sorghum. In this study, 16S rRNA amplicon sequencing was used to determine the impact of nitrogen fertilization on the development of the root-associated microbiomes of 10 sorghum genotypes grown in eastern Nebraska. We observed that early rhizosphere samples exhibit a significant reduction in overall diversity due to a high …