Agriculture Commons^™

Metabolic Engineering Of Oilseed Crops To Produce High Levels Of Novel Acetyl Glyceride Oils With Reduced Viscosity, Freezing Point And Calorific Value, Jinjie Liu, Adam Rice, Kathleen Mcglew, Vincent Shaw, Hyunwoo Park, Thomas E. Clemente, Mike Pollard, John Ohlrogge, Timothy P. Durrett

Department of Agronomy and Horticulture: Faculty Publications

Seed oils have proved recalcitrant to modification for the production of industrially useful lipids. Here, we demonstrate the successful metabolic engineering and subsequent field production of an oilseed crop with the highest accumulation of unusual oil achieved so far in transgenic plants. Previously, expression of the Euonymus alatus diacylglycerol acetyltransferase (EaDAcT) gene in wild-type Arabidopsis seeds resulted in the accumulation of 45 mol% of unusual 3-acetyl-1,2- diacyl-sn-glycerols (acetyl-TAGs) in the seed oil (Durrett et al., 2010 PNAS 107:9464). Expression of EaDAcT in dgat1 mutants compromised in their ability to synthesize regular triacylglycerols increased acetyl-TAGs to 65 mol%. Camelina and soybean …

Functional Genomics And Microbiome Profiling Of The Asian Longhorned Beetle (Anoplophora Glabripennis) Reveal Insights Into The Digestive Physiology And Nutritional Ecology Of Wood Feeding Beetles, Erin D. Scully, Scott M. Geib, John E. Carlson, Ming Tien, Duane Mckenna, Kelli Hoover

Department of Agronomy and Horticulture: Faculty Publications

Background: Wood-feeding beetles harbor an ecologically rich and taxonomically diverse assemblage of gut microbes that appear to promote survival in woody tissue, which is devoid of nitrogen and essential nutrients. Nevertheless, the contributions of these apparent symbionts to digestive physiology and nutritional ecology remain uncharacterized in most beetle lineages.

Results: Through parallel transcriptome profiling of beetle- and microbial- derived mRNAs, we demonstrate that the midgut microbiome of the Asian longhorned beetle (Anoplophora glabripennis), a member of the beetle family Cerambycidae, is enriched in biosynthetic pathways for the synthesis of essential amino acids, vitamins, and sterols. Consequently, the midgut …

Comprehensive Characterization And Rna-Seq Profiling Of The Hd-Zip Transcription Factor Family In Soybean (Glycine Max) During Dehydration And Salt Stress, Vikas Belamkar, Nathan T. Weeks, Arvind K. Bharti, Andrew Farmer, Michelle A. Graham, Steven B. Cannon

Department of Agronomy and Horticulture: Faculty Publications

Background:

The homeodomain leucine zipper (HD-Zip) transcription factor family is one of the largest plant specific superfamilies, and includes genes with roles in modulation of plant growth and response to environmental stresses. Many HD-Zip genes are characterized in Arabidopsis (Arabidopsis thaliana), and members of the family are being investigated for abiotic stress responses in rice (Oryza sativa), maize (Zea mays), poplar (Populus trichocarpa) and cucumber (Cucmis sativus). Findings in these species suggest HD-Zip genes as high priority candidates for crop improvement.

Results:

In this study we have identified members of …

Registration Of ‘Ci0947bmr’ Sorghum, O. R. Portillo, R. Clara-Valencia, J. Ramírez, R. Estebez, M. Hernández, A. Morán, R. Obando, N. Gutiérrez, R. Tinoco-Mora, N. De Gracia, D. Herrera, Luis Orlindo Tedeschi, W. L. Rooney

INTSORMIL Scientific Publications

The sorghum [Sorghum bicolor (L.) Moench] cultivar CI0947bmr (Reg. No. CV-137, PI 672153) was jointly developed and released by the Centro Nacional de Tecnología Agropecuaria y Forestal (CENTA) research program in El Salvador and the Texas A&M Agrilife Research sorghum breeding program in 2013. CI0947bmr is a brown midrib (bmr), dual-purpose sorghum selected for productivity in Central American environments. CI0947bmr was developed from a pedigree breeding program, and it was derived from a BC₁F₂ population of the pedigree B03292bmr/Tortillero//Tortillero. All generation advancement and selection were completed in San Andres, El Salvador. To confirm performance …

Abcb11 Functions With B1 And B19 To Regulate Rootward Auxin Transport, Jesica Elyse Reemmer

Open Access Theses

Auxin transport is essential for the architecture and development of erect plants. In a network of transporters directing auxin flows, ATP-Binding Cassette (ABC) transporters are a ubiquitous family of proteins that actively transport important substrates, including auxins, across the plasma membrane. ABCB1 and ABCB19 have been shown to account for the majority of rootward auxin transport, but residual fluxes to the root tip in Arabidopsis b1b19 double mutants implies the involvement of at least one additional auxin transporter in this process. Of specific interest, the severe dwarfism seen in abcb1abcb19 is strikingly reminiscent of that seen in mutants defective in …

Synthesis Of The Effect Of Fire On Lesser Prairie‐Chickens, Eric Thacker, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

In this synthesis, we reviewed the scientific literature pertaining to the effects of fire on lesser prairie‐chickens and their habitat. Overall, research is generally lacking that directly assesses relationships among fire, both as a regime and a discrete event, to its effect on lesser prairie‐chicken behavior and habitat value. Yet, research has quantified the effects of fire on vegetation throughout the distribution of the lesser prairie‐chicken, which has been linked to known metrics of habitat value and broad landscape‐level habitat requirements.

To summarize the literature, lesser prairie‐chickens require broad landscapes of fire‐dependent grass‐shrub vegetation. Changes in the eco‐evolutionary fire regime …

Stacking Of A Stearoyl-Acp Thioesterase With A Dual-Silenced Palmitoyl-Acp Thioesterase And Δ12 Fatty Acid Desaturase In Transgenic Soybean, Hyunwoo Park, George L. Graef, Yixiang Xu, Patrick Tenopir, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Soybean (Glycine max (L.) Merr) is valued for both its protein and oil, whose seed is composed of 40% and 20% of each component, respectively. Given its high percentage of polyunsaturated fatty acids, linoleic acid and linolenic acid, soybean oil oxidative stability is relatively poor. Historically food processors have employed a partial hydrogenation process to soybean oil as a means to improve both the oxidative stability and functionality in end-use applications. However, the hydrogenation process leads to the formation of trans-fats, which are associated with negative cardiovascular health. As a means to circumvent the need for the hydrogenation process, genetic …

Maine's Kelp Highway, Catherine Schmitt

Catherine Schmitt

No abstract provided.

First Report Of Curvularia Inaequalis And Bipolaris Spicifera Causing Leaf Blight Of Buffalograss In Nebraska, B. S. Amaradasa, K. Amundsen

Department of Agronomy and Horticulture: Faculty Publications

During the summer of 2011, foliar blight was observed on buffalograss (Buchloë dactyloides (Nutt.) Engelm.) lawns in Lincoln and Waverly, Nebraska. Disease symptoms were common when buffalograss was growing above 30°C and in drought conditions. Disease symptoms began as dark brown oblong leaf spots, followed by leaf tip dieback and eventual blighting of entire tillers. Leaf infections would progress into patches of thinning turf. Diseased leaf pieces were rinsed in distilled water and placed on 1.5% water agar. Two mitosporic fungal species having conidial morphology of Curvularia and Bipolaris were isolated. Colonies of Curvularia isolates grown on ¼× PDA …

Letter From The Dean, Michael Vayda

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Multilocation Corn Stover Harvest Effects On Crop Yields And Nutrient Removal, Douglas L. Karlen, Stuart J. Birrell, Jane M.F. Johnson, Shannon L. Osborne, Thomas E. Schumacher, Gary E. Varvel, Richard B. Ferguson, Jeff M. Novak, James R. Frederick, John M. Baker, John A. Lamb, Paul R. Alder, Greg W. Roth, Emerson D. Nafziger

Department of Agronomy and Horticulture: Faculty Publications

Corn (Zea mays L.) stover was identified as an important feedstock for cellulosic bioenergy production because of the extensive area upon which the crop is already grown. This report summarizes 239 site-years of field research examining effects of zero, moderate, and high stover removal rates at 36 sites in seven different states. Grain and stover yields from all sites as well as N, P, and K removal from 28 sites are summarized for nine longitude and six latitude bands, two tillage practices (conventional vs no tillage), two stoverharvest methods (machine vs calculated), and two crop rotations {continuous corn (maize) …

Evaluation Of Soilless Media Sensors For Managing Winter-Time Greenhouse Strawberry Production Using A Capmat System, George E. Meyer, Ellen T. Paparozzi, Stacy A. Adams, Diego Scacalossi Voltan

Department of Agronomy and Horticulture: Faculty Publications

It is important for a greenhouse strawberry grower to know that their capillary mat (CapMat™) fertigation system is working correctly and that plants are receiving the correct amounts of water and fertilizer. Pots with soilless mix are not expected to hold more than 70% water on a volumetric basis. Pots with less than 40% water content continuously are not supplied enough water and nutrients to the plants. Typically, pots located near the manifold distribution system get a little more water than those at the other locations, but water use will really vary according to the factors listed above as well …

Do Cover Crops Increase Or Decrease Nitrous Oxide Emissions? A Meta-Analysis, Andrea D. Basche, F. E. Miguez, T. C. Kaspar, M. J. Castellano

Department of Agronomy and Horticulture: Faculty Publications

There are many environmental benefits to incorporating cover crops into crop rotations, such as their potential to decrease soil erosion, reduce nitrate (NO₃) leaching, and increase soil organic matter. Some of these benefits impact other agroecosystem processes, such as greenhouse gas emissions. In particular, there is not a consensus in the literature regarding the effect of cover crops on nitrous oxide (N₂O) emissions. Compared to site-specific studies, meta-analysis can provide a more general investigation into these effects. Twenty-six peer-reviewed articles including 106 observations of cover crop effects on N₂O emissions from the soil surface …

Challenges And Opportunities In Transdisciplinary Science: The Experience Of Next Generation Scientists In An Agriculture And Climate Research Collaboration, Andrea D. Basche, Gabrielle E. Roesch-Mcnally, Lindsay A. Pease, Christopher D. Eidson, Guy Bou Lahdou, Mike W. Dunbar, Trevor J. Frank, Laura Frescoln, Lei Gu, Ryan Nagelkirk, Jose Pantoja, Adam K. Wilke

Department of Agronomy and Horticulture: Faculty Publications

Agriculture in the twenty-first century faces unprecedented challenges from increasing climate variability to growing demands on natural resources to globalizing economic markets. These emerging agricultural issues, spanning both human and natural dimensions, are uniquely formulated, exceedingly complex, and difficult to address within existing disciplinary domains (Eigenbrode et al. 2007; Reganold et al. 2011; Foley et al. 2005; Hansen et al. 2013). Therefore, the next generation of scientists working on these issues must not only be highly trained within a disciplinary context but must also have the capacity to collaborate with others to solve systems-level problems.

Eqtl Networks Reveal Complex Genetic Architecture In The Immature Soybean Seed, Yung-Tsi Bolon, D. Hyten, James H. Orf, Carroll P. Vance, Gary J. Muehlbauer

Department of Agronomy and Horticulture: Faculty Publications

The complex network of regulatory factors and interactions involved in transcriptional regulation within the seed is not well understood. To evaluate gene expression regulation in the immature seed, we utilized a genetical genomics approach on a soybean [Glycine max (L.) Merr.] recombinant inbred line (RIL) population and produced a genome-wide expression quantitative trait loci (eQTL) dataset. The validity of the dataset was confirmed by mapping the eQTL hotspot for flavonoid biosynthesis-related genes to a region containing repeats of chalcone synthase (CHS) genes known to correspond to the soybean inhibitor locus that regulates seed color. We then identified eQTL for …

The Carbon-Nitrogen Balance Of The Nodule And Its Regulation Under Elevated Carbon Dioxide Concentration, Marc Libault

Department of Agronomy and Horticulture: Faculty Publications

Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN₂). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the …

Identification Of Differentially Expressed Genes Between Sorghum Genotypes With Contrasting Nitrogen Stress Tolerance By Genome-Wide Transcriptional Profiling, Malleswari Gelli, Yongchao Duo, Anji Reddy Konda, Chi Zhang, David R. Holding, Ismail M. Dweikat

Department of Agronomy and Horticulture: Faculty Publications

Background: Sorghum is an important cereal crop, which requires large quantities of nitrogen fertilizer for achieving commercial yields. Identification of the genes responsible for low-N tolerance in sorghum will facilitate understanding of the molecular mechanisms of low-N tolerance, and also facilitate the genetic improvement of sorghum through marker-assisted selection or gene transformation. In this study we compared the transcriptomes of root tissues from seven sorghum genotypes having differential response to low-N stress.

Results: Illumina RNA-sequencing detected several common differentially expressed genes (DEGs) between four low-N tolerant sorghum genotypes (San Chi San, China17, KS78 and high-NUE bulk) and three …

A Genome-Wide Association Study Of Seed Protein And Oil Content In Soybean, Eun-Young Hwang, Qijian Song, Gaofeng Jia, James E. Specht, David L. Hyten, Jose Costa, Perry B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Background: Association analysis is an alternative to conventional family-based methods to detect the location of gene(s) or quantitative trait loci (QTL) and provides relatively high resolution in terms of defining the genome position of a gene or QTL. Seed protein and oil concentration are quantitative traits which are determined by the interaction among many genes with small to moderate genetic effects and their interaction with the environment. In this study, a genome-wide association study (GWAS) was performed to identify quantitative trait loci (QTL) controlling seed protein and oil concentration in 298 soybean germplasm accessions exhibiting a wide range of …

Comparison Of Winter Strawberry Production In A Commercial Heated High Tunnel Versus A University Greenhouse, Ellen T. Paparozzi, Ryan Pekarek, George E. Meyer, Stacy A. Adams, M. Elizabeth Conley, David P. Lambe, Paul Read, Erin E. Blankenship

Department of Agronomy and Horticulture: Faculty Publications

For the past 4 years, the University of Nebraska strawberry team has worked to develop low cost, sustainable methods for farmers and growers to produce strawberries in a double polyethylene greenhouse during the winter. This past year, this growing system was adapted to become a commercial grower’s heated high tunnel for the winter/spring of 2013-14. The idea was to scale up to a farm-size demonstration and compare it to the university greenhouse production system with a goal to expand marketing opportunities for strawberries into the winter season.

Greenhouse Gas Emissions From Soil Treated With Dung Pats, Kenneth Evans, Ana Wingeyer, Martha Mamo, Walter H. Schacht, Pamela Sutton, Kent M. Eskridge

Department of Agronomy and Horticulture: Faculty Publications

No abstract provided.

Grazing Management Effect On Micro- And Macro- Scale Fate Of C And N In Rangelands, Martha Mamo, Jeff Bradshaw, Richard Ferguson, Kent M. Eskridge, John A. Guretzky, Karla Jenkins, Walter H. Schacht, Jerry Volesky, Sean Whipple, Anita Wingeyer, Haishun Yang

Department of Agronomy and Horticulture: Faculty Publications

No abstract provided.

Fate Of C And N From Dung Pats Into Soil, Kenneth Evans, Ana Wingeyer, Martha Mamo, Pamela Sutton, Jeff Bradshaw, Kent M. Eskridge, Matt Judkins, Jenna Beckmann, Erin Hatch

Department of Agronomy and Horticulture: Faculty Publications

No abstract provided.

Switchgrass (Panicum Virgatum L) Flag Leaf Transcriptomes Reveal Molecular Signatures Of Leaf Development, Senescence, And Mineral Dynamics, Nathan A. Palmer, Teresa Donze-Reiner, David Horvath, Tiffany Heng-Moss, Brian M. Waters, Christian M. Tobias, Gautam Sarath

Department of Agronomy and Horticulture: Faculty Publications

Switchgrass flag leaves can be expected to be a source of carbon to the plant, and its senescence is likely to impact the remobilization of nutrients from the shoots to the rhizomes. However, many genes have not been assigned a function in specific stages of leaf development. Here, we characterized gene expression in flag leaves over their development. By merging changes in leaf chlorophyll and the expression of genes for chlorophyll biosynthesis and degradation, a four-phase molecular roadmap for switchgrass flag leaf ontogeny was developed. Genes associated with early leaf development were up-regulated in phase 1. Phase 2 leaves had …

Phytophthora Root Rot Resistance In Soybean E00003, Zhongnan Zhang, Jianjun Hao, Jiazheng Yuan, Qijian Song, D. L. Hyten, P. B. Cregan, Guorong Zhang, Cuihua Gu, Ming Li, Dechun Wang

Department of Agronomy and Horticulture: Faculty Publications

Phytophthora root rot (PRR) is a devastating disease in soybean [Glycine max (L.) Merr.] production. Michigan elite soybean E00003 is resistant to Phytophthora sojae and has been used as a resistance source in breeding. Genetic control of PRR resistance in this source is unknown. To facilitate marker-assisted selection (MAS), the PRR resistance loci in E00003 and their map locations need to be determined. In this study, a genetic mapping approach was used to identify major PRR -resistant loci in E00003. The mapping population consists of 240 F₄–derived lines developed by crossing E00003 with the P. sojae susceptible …

Quantitative Trait Locus Analysis Of Unsaturated Fatty Acids In A Recombinant Inbred Population Of Soybean, Xianzhi Wang, Guo-Liang Jiang, Marci Green, Roy A. Scott, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] is an important oilseed crop which produces about 30 %of the world’s edible vegetable oil. The quality of soybean oil is determined by its fatty acid composition. Soybean oil high in oleic and low in linolenic fatty acids is desirable for human consumption and other uses. The objectives of this study were to identify quantitative trait loci (QTLs) for unsaturated fatty acids and to evaluate the genetic effects of single QTL and QTL combinations in soybean. A population of recombinant inbred lines derived from the cross of SD02-4-59 X A02-381100 was evaluated for fatty …

Quantitative Trait Loci (Qtl) That Underlie Scn Resistance In Soybean [Glycine Max (L.) Merr.] Pi438489b By ‘Hamilton’ Recombinant Inbred Line (Ril) Population, Kassem My Abdelmajid, Laura Ramos, D. L. Hyten, Jason Bond, Abdelhafid Bendahmane, Prakash R. Arelli, Victor N. Njiti, Silvia Cianzio, Stella K. Kantartzi, Khalid Meksem

Department of Agronomy and Horticulture: Faculty Publications

Soybean cyst nematode caused by Heterodera glycines Ichinohe is the most devastating pest in soybean [Glycine max (L.) Merr.]. Resistance to SCN is complex, polygenic, race and cultivar specific, and it is controlled by several quantitative trait loci (QTL). Our objective was to identify and map QTL for SCN resistance to races 3 (HG Type 0) and 5 (HG Type 2.5.7) using a high density SNP-based genetic linkage map based on the PI438489B by ‘Hamilton’ (PIxH, n=50) recombinant inbred line population. The PI438489B by Hamilton map contained 648 SNPs distributed on 31 LGs with coverage of 1,524.7 cM and …

Detection And Confirmation Of Quantitative Trait Loci For Soybean Seed Isoflavones, Christopher J. Smallwood, Catherine N. Nyinyi, Dean A. Kopsell, Carl E. Sams, Dennis R. West, Pengyin Chen, Stella K. Kantartzi, P. B. Cregan, D. L. Hyten, Vincent R. Pantalone

Department of Agronomy and Horticulture: Faculty Publications

Interest in soybean [Glycine max (L.) Merr.] isoflavones has increased in recent years owing to numerous reported health benefits. Consequently, quantitative trait loci (QTL) detection for marker-assisted breeding for isoflavones is being examined for genetic gains. This study sought to detect QTL for soybean isoflavones in a population of 274 recombinant inbred lines derived from a cross between ‘Essex’ and ‘Williams 82’ that were subdivided and tested by maturity (early, mid, and late). The field tests were conducted in three environments in 2009 (Knoxville, TN; Harrisburg, IL; and Stuttgart, AR). The population was genotyped with 480 polymorphic single nucleotide …

Mapping The Low Palmitate Fap1 Mutation And Validation Of Its Effects In Soybean Oil And Agronomic Traits In Three Soybean Populations, Andrea J. Cardinal, Rebecca Whetten, Sanbao Wang, Jérôme Auclair, D. L. Hyten, P. B. Cregan, Eleni Bachlava, Jason Gillman, Martha Ramirez, Ralph Dewey, Greg Upchurch, Lilian Miranda, Joesph W. Burton

Department of Agronomy and Horticulture: Faculty Publications

Soybean oil with reduced palmitic acid content is desirable to reduce the health risks associated with consumption of this fatty acid. The objectives of this study were: to identify the genomic location of the reduced palmitate fap1 mutation, determine its molecular basis, estimate the amount of phenotypic variation in fatty acid composition explained by this locus, determine if there are epistatic interactions between the fap1 and fap_nc loci and, determine if the fap1 mutation has pleiotropic effects on seed yield, oil and protein content in three soybean populations. This study detected two major QTL for 16:0 content located in …

A Reference Genome For Common Bean And Genome-Wide Analysis Of Dual Domestications, Jeremy Schmutz, Phillip E. Mcclean, Sujan Mamidi, G. Albert Wu, Steven B. Cannon, Jane Grimwood, Jerry Jenkins, Shengqiang Shu, Qijian Song, Carolina Chavarro, Mirayda Torres-Torres, Valerie Geffroy, Samira Mafi Moghaddam, Dongying Gao, Brian Abernathy, Kerrie Barry, Matthew Blair, Mark A. Brick, Mansi Chovatia, Paul Gepts, David M. Goodstein, Michael Gonzales, Uffe Hellsten, D. L. Hyten, Gaofeng Jia, James D. Kelly, Dave Kudrna, Rian Lee, Manon M.S. Richard, Phillip N. Miklas, Juan M. Osorno, Josiane Rodrigues, Vincent Thareau, Carlos A. Urrea Florez, Mei Wang, Yeisoo Yu, Ming Zhang, Rod A. Wing, P. B. Cregan, Daniel S. Rokhsar, Scott A. Jackson

Department of Agronomy and Horticulture: Faculty Publications

Common bean (Phaseolus vulgaris L.) is the most important grain legume for human consumption and has a role in sustainable agriculture owing to its ability to fix atmospheric nitrogen. We assembled 473 Mb of the 587-Mb genome and genetically anchored 98% of this sequence in 11 chromosome-scale pseudomolecules. We compared the genome for the common bean against the soybean genome to find changes in soybean resulting from polyploidy. Using resequencing of 60 wild individuals and 100 landraces from the genetically differentiated Mesoamerican and Andean gene pools, we confirmed 2 independent domestications from genetic pools that diverged before human colonization. …

Identification Of New Qtls For Seed Mineral, Cysteine, And Methionine Concentrations In Soybean [Glycine Max (L.) Merr.], Raghuprakash Kastoori Ramamurthy, Joseph Jedlicka, George L. Graef, Brian M. Waters

Department of Agronomy and Horticulture: Faculty Publications

Increased concentrations of important nutrients in edible parts of plants could result in biofortified foods. Soybean [Glycine max (L.) Merr.] is a major legume crop and an important source of certain nutrients, including protein and minerals, in human and animal diets. Understanding the underlying genetic basis of seed composition is crucial to improving seed nutrient composition. In this study we used three soybean recombinant inbred line mapping populations derived from the crosses Williams 82 × DSR-173, Williams 82 × NKS19-90 and Williams 82 × Vinton 81, and constructed a joint linkage map from these populations. Forty quantitative trait loci (QTLs) …