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Full-Text Articles in Life Sciences

Canavalia And Dolichos Extracts For Sustainable Pest Biocontrol And Plant Nutrition Improvement In El Salvador, Carlos Martinez Oct 2019

Canavalia And Dolichos Extracts For Sustainable Pest Biocontrol And Plant Nutrition Improvement In El Salvador, Carlos Martinez

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Botanical repellents and pesticides are now being rediscovered as new tools for integrated pest management in order to reduce the use of toxic chemicals in crop production. Canavalia gladiata and Dolichos lablab are two Fabaceae very well adapted to farmlands of El Salvador, effective as living barriers and mostly as cover crops, however, they are not yet very well disseminated. This document describes the potential for using the liquid extracts and the dry flour of raw seeds of those plants for economic benefit and practical convenience for pest management in Salvadorian agriculture under field conditions. Seed extracts were useful when ...


An Integrated Genomics And Phenomics Approach To Study The Evolution Of C4 Photosynthesis, Daniel Santana De Carvalho Aug 2019

An Integrated Genomics And Phenomics Approach To Study The Evolution Of C4 Photosynthesis, Daniel Santana De Carvalho

Theses, Dissertations, and Student Research in Agronomy and Horticulture

The C4 photosynthetic pathway was first described over 50 years ago. Today, it is known that C4 evolved independently > 60 in plant lineages, which involves understanding not only the genetic, but also the metabolic features and differences involved in this process. Also, several adaptations are involved in the evolution of this type of photosynthesis, for example: changes in leaf anatomy and the evolution of kranz anatomy, physiology and metabolic pathways. In order to further investigate this pathway, different technologies and methods have been developed to unravel genes involved in C4 photosynthesis. With the advances in molecular biology and bioinformatics tools ...


Investigating Parental Effects On End-Use Quality In Hard Winter Wheat (Triticum Aestivum L.) Hybrids, Anthony Delaney Aug 2019

Investigating Parental Effects On End-Use Quality In Hard Winter Wheat (Triticum Aestivum L.) Hybrids, Anthony Delaney

Theses, Dissertations, and Student Research in Agronomy and Horticulture

To optimize the performance and marketing of hybrid wheat, breeders need to understand the impact parents have on end-use quality. The goal of this study was to investigate the inheritance of end-use quality traits of hard winter wheat reciprocal hybrids produced by Easterly (2017). The 2016 analysis included 71 reciprocal hybrid combinations from 13 parents and the 2017 analysis included 79 reciprocal hybrid combinations from 14 parents. The reciprocals were composed of crosses between the top performing and bottom performing parents with respect to end-use quality as quantified by a Mixograph, a SDS sedimentation assay, and a SDS-SRC hybrid assay ...


Rust And Viral Mosaic Diseases In Biofuel Switchgrass, Anthony A. Muhle Aug 2019

Rust And Viral Mosaic Diseases In Biofuel Switchgrass, Anthony A. Muhle

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Switchgrass (Panicum virgatum L.) is a perennial warm-season monocot that is indigenous to locations in North America east of the Rocky Mountains, and is considered a model grass for biofuel feedstock production. As switchgrass production increases, diseases pose a potential threat to biomass production and ethanol extraction. The two predominant switchgrass diseases in Nebraska are rust caused by Puccinia spp. and a viral mosaic disease caused by Panicum mosaic virus (PMV) and its associated Satellite panicum mosaic virus (SPMV). In this thesis, one study determined how SPMV affects PMV infection and systemic spread in two populations of switchgrass at different ...


Hormonal Signaling Induced In Soybean By Lysobacter Enzymogenes Strain C3, Jessica C. Walnut Aug 2019

Hormonal Signaling Induced In Soybean By Lysobacter Enzymogenes Strain C3, Jessica C. Walnut

Theses, Dissertations, and Student Research in Agronomy and Horticulture

The biological control bacterium Lysobacter enzymogenes strain C3 has been shown to suppress fungal diseases by producing a suite of lytic enzymes and antimicrobial secondary metabolites. Previous studies have found that C3, when applied to grass and cereal plants, also is capable of inducing local and systemic resistance against fungal pathogens. It is unknown, however, whether the bacterium has the ability to induce resistance in dicots and what signaling pathways are involved. This study assessed the ability of C3 to trigger local and systemic induced resistance responses in soybean (Glycine max ‘Williams82’) by analyzing relative expression of salicylic acid (SA ...


Biomethane Production From Distillery Wastewater, Zachary Christman Jun 2019

Biomethane Production From Distillery Wastewater, Zachary Christman

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Distillery wastewater treatment is a great ecological problem, for example, India produces 2.7 billion liters of alcohol that results in 40 billion liters of wastewater. However, this material can be seen as a resource since 11 million cubic meters of biogas at 60% methane could be produced in addition to cleaning the water. The distillery has two options of what to do with the biogas. The first is to use the biogas to fuel the distillery making the production plant more energy efficient and removing some of the need to buy natural gas. The other is to upgrade the ...


Introduction To Sorghum Paper Production, Zachary Christman May 2019

Introduction To Sorghum Paper Production, Zachary Christman

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Sorghum is a tall grass used for many commercial products such as fodder and syrup. The 10 to 15 feet stalk of the plant has lower lignin than wood and provides a fiber length of 2.31 mm in the outer covering and 1.38 mm for the leaf. Sorghum fiber makes a high quality, strong paper suitable for printing, packaging and paperboard.


Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson May 2019

Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Seedling disease is one the most economically important diseases of soybean in the United States. It is commonly caused by Fusarium spp., Rhizoctonia solani, Pythium spp., and Phytophthora sojae, alone, or together as a disease complex. Fungicide seed treatments continue to provide the most consistent management of seedling diseases. Soil-applied protoporphyrinogen oxidase (PPO) inhibitor herbicides are used preemergence in soybean production to manage several broadleaf weeds. Applications of PPO-inhibitors can result in phytotoxic injury to soybean when environmental conditions are not favorable for soybean growth. These environmental conditions can favor seedling disease development as well. In this thesis, two studies ...


Use Of Annual Forage Mixtures In Crop/Livestock Production Systems In Nebraska, Nathan Paul Pflueger May 2019

Use Of Annual Forage Mixtures In Crop/Livestock Production Systems In Nebraska, Nathan Paul Pflueger

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Success of integrating annual forages into crop and livestock systems throughout Nebraska may be variable depending on field location, field/forage crop management, and precipitation. There are many different warm- and cool-season annual forage species available for integrating crop and livestock systems at different times of the year. Mixtures of cereal species, such as oats (Avena sativa)) and spring peas (Pisum sativum)), are often used to optimize forage quantity and forage quality. Our two-year, three location study across Nebraska’s precipitation gradient suggested that forage quantity and quality may vary by location due to different precipitation amounts received during the ...


Dna Barcoding Of Pratylenchus From Agroecosystems In The Northern Great Plains Of North America, Mehmet Ozbayrak May 2019

Dna Barcoding Of Pratylenchus From Agroecosystems In The Northern Great Plains Of North America, Mehmet Ozbayrak

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Pratylenchus species are among the most common plant parasitic nematodes in the Great Plains Region. The objectives of this study were to barcode Pratylenchus specimens for species identification in the Great Plains region using mitochondrial CO1 DNA barcode. In order to (1) determine species boundaries, (2) assess the host associations of barcoded Pratylenchus, (3) to determine the distribution patterns across the Great Plains Region and, (4) to evaluate the species status of P. scribneri and P. hexincisus by a multivariate morphological analysis of haplotype groups identified by DNA barcoding. Soil samples, primarily associated with eight major crops, were collected from ...


Establishment Of Perennial Legumes With An Annual Warm-Season Grass As A Companion Crop, Martina N. La Vallie May 2019

Establishment Of Perennial Legumes With An Annual Warm-Season Grass As A Companion Crop, Martina N. La Vallie

Theses, Dissertations, and Student Research in Agronomy and Horticulture

The yields of perennial forage legumes are often hindered during the establishment year due to slow germination rates and weed competition. This study was conducted to determine if sorghum-sudangrass (Sorghum bicolor x S. bicolor var. sudanese) is a compatible annual companion crop for increased forage production, weed suppression, and legume establishment. In 2016, sorghum-sudangrass was paired with alfalfa (Medicago sativa L. ‘Ranger’), birdsfoot trefoil (Lotus corniculatus L.), Illinois bundleflower [Desmanthus illinoensis (Michx.) MacMill. ex B.L. Rob. & Fernald], purple prairie clover (Dalea purpurea Vent.), red clover (Trifolium pratense L.), and roundhead lespedeza (Lespedeza capitata Michx.). We studied effects of a sorghum-sudangrass companion crop with a varying number of harvests (three vs. four harvests) collected per plot throughout the summer and compared yields to the yield of a weeded legume treatment, and a non-weeded legume treatment. In 2017, we studied effects of the application of four seeding rates for sorghum-sudangrass at 5 pure live seed per m2 (PLS/m2), 10 PLS/m2, 20 PLS/m2, and 40 PLS/m2 paired with only the alfalfa perennial legume and compared yields to the yield of an oat-alfalfa control treatment, a weeded alfalfa treatment, and a non-weeded alfalfa treatment. Total dry matter yields along with the yield of each legume, weeds, sorghum-sudangrass, and oats (second year only) were collected for each treatment. In both years, we found the addition of sorghum-sudangrass increased overall dry matter yield and significantly decreased weed abundance. The increase in total dry matter yield came at a cost to the legume yield; as treatments planted with sorghum-sudangrass or oats had lower legume/alfalfa yields than weeded legume/alfalfa treatments. These results suggest that sorghum-sudangrass is ...


Genome-Wide Association Studies In Maize And Sorghum, Preston Hurst Apr 2019

Genome-Wide Association Studies In Maize And Sorghum, Preston Hurst

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Genome-wide association studies are used to identify genetic variants associated with a particular phenotype. GWAS has been used in a variety of taxa, from humans, to fish to plants . The present analysis is focused on two species important to the human species: maize and sorghum. A GWAS in maize was carried out on the modification of the Ga1-s allele. The Ga1 locus has long been studied as being involved in a unilateral crossing barrier . However, it has long been suspected that the locus is modified by background genetic factors . GWAS was used to observe candidates for this modification. A series ...


Improving The Distribution And Use Of Biogas By Conversion To Methanol, Zachary Christman Mar 2019

Improving The Distribution And Use Of Biogas By Conversion To Methanol, Zachary Christman

Theses, Dissertations, and Student Research in Agronomy and Horticulture

In this technology review, the process of turning an average biogas into methanol will be presented. The purpose is to find a better method of transporting the energy contained within biogas so that it may be used in industry as a value added product. The first step is removal of hydrogen sulfide, a corrosive chemical that can breakdown mechanical parts. The second step is carbon capture and conversion of the biogas into hydrogen. The final step is the hydrogenation of carbon dioxide into methanol using a copper catalyst and an alcohol co-catalyst.


Beyond Bird Feed: Proso Millet For Human Health And Environment, Saurav Das, Rituraj Khound, Meenakshi Santra, Dipak K. Santra Jan 2019

Beyond Bird Feed: Proso Millet For Human Health And Environment, Saurav Das, Rituraj Khound, Meenakshi Santra, Dipak K. Santra

Agronomy & Horticulture -- Faculty Publications

Domesticated in 8000–10,000 BP in northern China, proso millet (Panicum miliaceum L.) is the best adaptive rotational crop for semiarid central High Plains of the USA, where average annual precipitation is 356–407 mm. Proso millet has multiple benefits when consumed as human food. Proso millet is rich in minerals, dietary fiber, polyphenols, vitamins and proteins. It is gluten-free and therefore, ideal for the gluten intolerant people. Proso millet contains high lecithin which supports the neural health system. It is rich in vitamins (niacin, B-complex vitamins, folic acid), minerals (P, Ca, Zn, Fe) and essential amino acids (methionine ...


A Small Viral Potassium Ion Channel With An Inherent Inward Rectification, Denise Eckert, Tobias Schulze, Julian Stahl, Oliver Rauh, James L. Van Etten, Brigitte Hertel, Indra Schroeder, Anna Moroni, Gerhard Thiel Jan 2019

A Small Viral Potassium Ion Channel With An Inherent Inward Rectification, Denise Eckert, Tobias Schulze, Julian Stahl, Oliver Rauh, James L. Van Etten, Brigitte Hertel, Indra Schroeder, Anna Moroni, Gerhard Thiel

Papers in Plant Pathology

Some algal viruses have coding sequences for proteins with structural and functional characteristics of pore modules of complex K+ channels. Here we exploit the structural diversity among these channel orthologs to discover new basic principles of structure/function correlates in K+ channels. The analysis of three similar K+ channels with ≤ 86 amino acids (AA) shows that one channel (Kmpv1) generates an ohmic conductance in HEK293 cells while the other two (KmpvSP1, KmpvPL1) exhibit typical features of canonical Kir channels. Like Kir channels, the rectification of the viral channels is a function of the K+ driving force. Reconstitution ...


Cryopreservation Of Paramecium Bursaria Chlorella Virus-1 During An Active Infection Cycle Of Its Host, Samantha R. Coy, Alyssa N. Alsante, James L. Van Etten, Steven W. Wilhelm Jan 2019

Cryopreservation Of Paramecium Bursaria Chlorella Virus-1 During An Active Infection Cycle Of Its Host, Samantha R. Coy, Alyssa N. Alsante, James L. Van Etten, Steven W. Wilhelm

Papers in Plant Pathology

Best practices in laboratory culture management often include cryopreservation of microbiota, but this can be challenging with some virus particles. By preserving viral isolates researchers can mitigate genetic drift and laboratory-induced selection, thereby maintaining genetically consistent strains between experiments. To this end, we developed a method to cryopreserve the model, green-alga infecting virus, Paramecium bursaria Chlorella virus 1 (PBCV-1). We explored cryotolerance of the infectivity of this virus particle, whereby freezing without cryoprotectants was found to maintain the highest infectivity (~2.5%). We then assessed the cryopreservation potential of PBCV-1 during an active infection cycle in its Chlorella variabilis NC64A ...


Relationships Between Wildfire Burn Severity, Cavity-Nesting Bird Assemblages, And Habitat In An Eastern Ponderosa Pine Forest, Emma C. Keele, Victoria M. Donovan, Caleb P. Roberts, Sarah M. Nodskov, Carissa L. Wonkka, Craig R. Allen, Larkin A. Powell, David A. Wedin, David G. Angeler, Dirac Twidwell Jan 2019

Relationships Between Wildfire Burn Severity, Cavity-Nesting Bird Assemblages, And Habitat In An Eastern Ponderosa Pine Forest, Emma C. Keele, Victoria M. Donovan, Caleb P. Roberts, Sarah M. Nodskov, Carissa L. Wonkka, Craig R. Allen, Larkin A. Powell, David A. Wedin, David G. Angeler, Dirac Twidwell

Agronomy & Horticulture -- Faculty Publications

Historically, eastern ponderosa pine (Pinus ponderosa) forests were described as sparse patches of old-growth trees maintained by frequent, low-severity fires; however, in recent decades, there have been a number of large mixed-severity wildfires throughout the range of these forests. Wildlife responses to severe fire disturbance in eastern ponderosa pine forests are not well understood. Our study investigates how cavity-nesting bird species in an eastern ponderosa pine forest are impacted by burn severity. The objectives of our study were to: (1) identify the community composition of cavity-nesting birds in a 27 y old burn of mixed severity, (2) assess how habitat ...


Spatial Variability Of Soil Properties Under Different Land Use In The Dang District Of Nepal, Dinesh Panday, Roshan Babu Ojha, Devraj Chalise, Saurav Das, Bikesh Twanabasu Jan 2019

Spatial Variability Of Soil Properties Under Different Land Use In The Dang District Of Nepal, Dinesh Panday, Roshan Babu Ojha, Devraj Chalise, Saurav Das, Bikesh Twanabasu

Agronomy & Horticulture -- Faculty Publications

Increased nutrient mining, soil erosion, and limited nutrient management has led to declines in soil quality and reduced productivity in many parts of Nepal. A study was conducted in the eastern part of the Dang district of Nepal in 2015 to assess the variability of selected soil properties of three different land use types (agricultural, agroforestry, and grassland) and to map their spatial distribution. A total of 120 soil samples were collected from 0–15 cm depth and analyzed for soil fertility parameters: pH, organic matter (OM), nitrogen (N), phosphorus (P), potassium (K), boron (B), and zinc (Zn). Results revealed ...


Global Responses Of Resistant And Susceptible Sorghum (Sorghum Bicolor) To Sugarcane Aphid (Melanaphis Sacchari), Hannah M. Tetreault, Sajjan Grover, Erin D. Scully, Tammy Gries, Nathan A. Palmer, Gautam Sarath, Joe Louis, Scott E. Sattler Jan 2019

Global Responses Of Resistant And Susceptible Sorghum (Sorghum Bicolor) To Sugarcane Aphid (Melanaphis Sacchari), Hannah M. Tetreault, Sajjan Grover, Erin D. Scully, Tammy Gries, Nathan A. Palmer, Gautam Sarath, Joe Louis, Scott E. Sattler

Agronomy & Horticulture -- Faculty Publications

The sugarcane aphid (Melanaphis sacchari) has emerged as a significant pest for sorghum. The use of sugarcane aphid-resistant sorghum germplasm with integrated pest management strategies appears to be an excellent solution to this problem. In this study, a resistant line (RTx2783) and a susceptible line (A/BCK60) were used to characterize the differences in plant responses to the sugarcane aphid through a series of experiments, which examined global sorghum gene expression, aphid feeding behavior and inheritance of aphid resistance. The global transcriptomic responses to sugarcane aphids in resistant and susceptible plants were identified using RNA-seq and compared to the expression ...


Fire Legacies In Eastern Ponderosa Pine Forests, Caleb P. Roberts, Victoria M. Donovan, Carissa L. Wonkka, Larkin A. Powell, Craig R. Allen, David G. Angeler, David A. Wedin, Dirac L. Twidwell Jr Jan 2019

Fire Legacies In Eastern Ponderosa Pine Forests, Caleb P. Roberts, Victoria M. Donovan, Carissa L. Wonkka, Larkin A. Powell, Craig R. Allen, David G. Angeler, David A. Wedin, Dirac L. Twidwell Jr

Agronomy & Horticulture -- Faculty Publications

Disturbance legacies structure communities and ecological memory, but due to increasing changes in disturbance regimes, it is becoming more difficult to characterize disturbance legacies or determine how long they persist. We sought to quantify the characteristics and persistence of material legacies (e.g., biotic residuals of disturbance) that arise from variation in fire severity in an eastern ponderosa pine forest in North America. We compared forest stand structure and understory woody plant and bird community composition and species richness across unburned, low‐, moderate‐, and high‐severity burn patches in a 27‐year‐old mixed‐severity wildfire that had received minimal ...


Response Surface Analysis Of Genomic Prediction Accuracy Values Using Quality Control Covariates In Soybean, Diego Jarquin, Reka Howard, George L. Graef, Aaron Lorenz Jan 2019

Response Surface Analysis Of Genomic Prediction Accuracy Values Using Quality Control Covariates In Soybean, Diego Jarquin, Reka Howard, George L. Graef, Aaron Lorenz

Agronomy & Horticulture -- Faculty Publications

An important and broadly used tool for selection purposes and to increase yield and genetic gain in plant breeding programs is genomic prediction (GP). Genomic prediction is a technique where molecular marker information and phenotypic data are used to predict the phenotype (eg, yield) of individuals for which only marker data are available. Higher prediction accuracy can be achieved not only by using efficient models but also by using quality molecular marker and phenotypic data. The steps of a typical quality control (QC) of marker data include the elimination of markers with certain level of minor allele frequency (MAF) and ...


Development Of Chlorophyll-Meter-Index-Based Dynamic Models For Evaluation Of High-Yield Japonica Rice Production In Yangtze River Reaches, Ke Zhang, Xiaojun Liu, Syed Tahir Ata-Ul-Karim, Songyang Li, Brian Krienke, Songyang Li, Qiang Cao, Yan Zhu, Weixing Cao, Yongchao Tian Jan 2019

Development Of Chlorophyll-Meter-Index-Based Dynamic Models For Evaluation Of High-Yield Japonica Rice Production In Yangtze River Reaches, Ke Zhang, Xiaojun Liu, Syed Tahir Ata-Ul-Karim, Songyang Li, Brian Krienke, Songyang Li, Qiang Cao, Yan Zhu, Weixing Cao, Yongchao Tian

Agronomy & Horticulture -- Faculty Publications

Accurate estimation of the nitrogen (N) spatial distribution of rice (Oryza sativa L.) is imperative when it is sought to maintain regional and global carbon balances. We systematically evaluated the normalized differences of the soil and plant analysis development (SPAD) index (the normalized difference SPAD indexes, NDSIs) between the upper (the first and second leaves from the top), and lower (the third and fourth leaves from the top) leaves of Japonica rice. Four multi-location, multi-N rate (0–390 kg ha-1) field experiments were conducted using seven Japonica rice cultivars (9915, 27123, Wuxiangjing14, Wunyunjing19, Wunyunjing24, Liangyou9, and Yongyou8). Growth analyses ...


The Genome Of Broomcorn Millet, Changsong Zou, Leiting Li, Daisuke Miki, Delin Li, Qiming Tang, Lihong Xiao, Santosh Rajput, Ping Deng, Li Peng, Wei Jia, Ru Huang, Meiling Zhang, Yidan Sun, Jiamin Hu, Xing Fu, Patrick S. Schnable, Yuxiao Chang, Feng Li, Hui Zhang, Baili Feng, Xinguang Zhu, Renyi Liu, James C. Schnable, Jian-Kang Zhu, Heng Zhang Jan 2019

The Genome Of Broomcorn Millet, Changsong Zou, Leiting Li, Daisuke Miki, Delin Li, Qiming Tang, Lihong Xiao, Santosh Rajput, Ping Deng, Li Peng, Wei Jia, Ru Huang, Meiling Zhang, Yidan Sun, Jiamin Hu, Xing Fu, Patrick S. Schnable, Yuxiao Chang, Feng Li, Hui Zhang, Baili Feng, Xinguang Zhu, Renyi Liu, James C. Schnable, Jian-Kang Zhu, Heng Zhang

Agronomy & Horticulture -- Faculty Publications

Broomcorn millet (Panicum miliaceum L.) is the most water-efficient cereal and one of the earliest domesticated plants. Here we report its high-quality, chromosome-scale genome assembly using a combination of short-read sequencing, single-molecule real-time sequencing, Hi-C, and a high-density genetic map. Phylogenetic analyses reveal two sets of homologous chromosomes that may have merged ~5.6 million years ago, both of which exhibit strong synteny with other grass species. Broomcorn millet contains 55,930 proteincoding genes and 339 microRNA genes. We find Paniceae-specific expansion in several subfamilies of the BTB (broad complex/tramtrack/bric-a-brac) subunit of ubiquitin E3 ligases, suggesting enhanced regulation ...


Engineering Linear, Branched-Chain Triterpene Metabolism In Monocots, Chase Kempinski, Zuodong Jiang, Garrett Zinck, Shirley J. Sato, Zhengxiang Ge, Thomas E. Clemente, Joseph Chappell Jan 2019

Engineering Linear, Branched-Chain Triterpene Metabolism In Monocots, Chase Kempinski, Zuodong Jiang, Garrett Zinck, Shirley J. Sato, Zhengxiang Ge, Thomas E. Clemente, Joseph Chappell

Agronomy & Horticulture -- Faculty Publications

Triterpenes are thirty-carbon compounds derived from the universal five-carbon prenyl precursors isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Normally, triterpenes are synthesized via the mevalonate (MVA) pathway operating in the cytoplasm of eukaryotes where DMAPP is condensed with two IPPs to yield farnesyl diphosphate (FPP), catalyzed by FPP synthase (FPS). Squalene synthase (SQS) condenses two molecules of FPP to generate the symmetrical product squalene, the first committed precursor to sterols and most other triterpenes. In the green algae Botryococcus braunii, two FPP molecules can also be condensed in an asymmetric manner yielding the more highly branched triterpene, botryococcene. Botryococcene is ...


Assessing Variation In Us Soybean Seed Composition (Protein And Oil), Yared Assefa, Larry C. Purcell, Montse Salmeron, Seth Naeve, Shaun N. Casteel, Peter Kovacs, Sotirios Archontoulis, Mark Licht, Fred Below, Herman Kandel, Laura E. Lindsey, John Gaska, Shawn Conley, Charles Shapiro, John M. Orlowski, Bobby R. Golden, Gurpreet Kaur, Maninderpal Singh, Kurt Thelen, Randall Laurenz, Dan Davidson, Igancio A. Ciampitti Jan 2019

Assessing Variation In Us Soybean Seed Composition (Protein And Oil), Yared Assefa, Larry C. Purcell, Montse Salmeron, Seth Naeve, Shaun N. Casteel, Peter Kovacs, Sotirios Archontoulis, Mark Licht, Fred Below, Herman Kandel, Laura E. Lindsey, John Gaska, Shawn Conley, Charles Shapiro, John M. Orlowski, Bobby R. Golden, Gurpreet Kaur, Maninderpal Singh, Kurt Thelen, Randall Laurenz, Dan Davidson, Igancio A. Ciampitti

Agronomy & Horticulture -- Faculty Publications

Soybean [Glycine max (L.) Merr.] seed composition and yield are a function of genetics (G), environment (E), and management (M) practices, but contribution of each factor to seed composition and yield are not well understood. The goal of this synthesis-analysis was to identify the main effects of G, E, and M factors on seed composition (protein and oil concentration) and yield. The entire dataset (13,574 data points) consisted of 21 studies conducted across the United States (US) between 2002 and 2017 with varying treatments and all reporting seed yield and composition. Environment (E), defined as site-year, was the dominant ...


When Viruses Infect Plants, Hernan Garcia-Ruiz Jan 2019

When Viruses Infect Plants, Hernan Garcia-Ruiz

Papers in Plant Pathology

Just as human beings can catch a cold, plants can also get viral infections. Understanding the mechanisms regulating the interactions between plants and viruses is the first step towards developing better management strategies and using biotechnology methods to immunise plants and engineer genetic resistance to viruses in plants. This is the focus of research by Dr Hernan Garcia-Ruiz and his team based at the University of Nebraska, USA.

Viral diseases in plants can cause important economic losses as a result of poor-quality products and lower yield. This impact can particularly seriously affect developing countries which are more likely to be ...


Host Factors Against Plant Viruses, Hernan Garcia Ruiz Jan 2019

Host Factors Against Plant Viruses, Hernan Garcia Ruiz

Papers in Plant Pathology

Plant virus genome replication and movement is dependent on host resources and factors. However, plants respond to virus infection through several mechanisms, such as autophagy, ubiquitination, mRNA decay and gene silencing, that target viral components. Viral factors work in synchrony with pro-viral host factors during the infection cycle and are targeted by antiviral responses. Accordingly, establishment of virus infection is genetically determined by the availability of the pro-viral factors necessary for genome replication and movement, and by the balance between plant defence and viral suppression of defence responses. Sequential requirement of pro-viral factors and the antagonistic activity of antiviral factors ...


Assessing The Value Of Grazed Corn Residue For Crop And Cattle Producers, Dread Redfearn, Jay Parsons, Mary Drewnoski, Marty Schmer, Rob Mitchell, James Macdonald, Jaymelynn Farney, Alexander Smart Jan 2019

Assessing The Value Of Grazed Corn Residue For Crop And Cattle Producers, Dread Redfearn, Jay Parsons, Mary Drewnoski, Marty Schmer, Rob Mitchell, James Macdonald, Jaymelynn Farney, Alexander Smart

Agronomy & Horticulture -- Faculty Publications

Integrated crop–livestock systems have included grazing perennial grasses during the spring and summer and corn (Zea mays L.) residues during the winter. Our objectives were to identify opportunities for expanded corn residue use through grazing and provide an economic assessment for value-added grazing. We estimated the economic value to the crop sector through grazing leased corn residue at over $95 million for Nebraska, South Dakota, Kansas, and North Dakota under current management. Additionally, gross economic value to the livestock sector in these states was estimated at greater than $191 million. Advantages for increased grazing use of corn residue include ...


Cover Crop Mixture Diversity, Biomass Productivity, Weed Suppression, And Stability, A. M. Florence, L. G. Higley, R. A. Drijber, C. A. Francis, J. L. Lindquist Jan 2019

Cover Crop Mixture Diversity, Biomass Productivity, Weed Suppression, And Stability, A. M. Florence, L. G. Higley, R. A. Drijber, C. A. Francis, J. L. Lindquist

Agronomy & Horticulture -- Faculty Publications

The diversity-productivity, diversity-invasibility, and diversity-stability hypotheses propose that increasing species diversity should lead, respectively, to increased average biomass productivity, invasion resistance, and stability. We tested these three hypotheses in the context of cover crop mixtures, evaluating the effects of increasing cover crop mixture diversity on above ground biomass, weed suppression, and biomass stability. Twenty to forty cover crop treatments were replicated three or four times at eleven sites using eighteen species representing three cover crop species each from six pre-defined functional groups: cool-season grasses, cool-season legumes, cool-season brassicas, warm-season grasses, warm-season legumes, and warm-season broadleaves. Each species was seeded as ...


Ponderosa Pine Regeneration,Wildland Fuels Management, And Habitat Conservation: Identifying Trade-Offs Following Wildfire, Victoria M. Donovan, Caleb P. Roberts, Carissa L. Wonkka, David A. Wedin, Dirac L. Twidwell Jan 2019

Ponderosa Pine Regeneration,Wildland Fuels Management, And Habitat Conservation: Identifying Trade-Offs Following Wildfire, Victoria M. Donovan, Caleb P. Roberts, Carissa L. Wonkka, David A. Wedin, Dirac L. Twidwell

Agronomy & Horticulture -- Faculty Publications

Increasing wildfires in western North American conifer forests have led to debates surrounding the application of post-fire management practices. There is a lack of consensus on whether (and to what extent) post-fire management assists or hinders managers in achieving goals, particularly in under-studied regions like eastern ponderosa pine forests. This makes it difficult for forest managers to balance among competing interests. We contrast structural and community characteristics across unburned ponderosa pine forest, severely burned ponderosa pine forest, and severely burned ponderosa pine forest treated with post-fire management with respect to three management objectives: ponderosa pine regeneration, wildland fuels control, and ...