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 …

2015 Spring Seed Guide, Teshome Regassa, Charles A. Shapiro

Department of Agronomy and Horticulture: Faculty Publications

NEBRASKA CORN HYBRID TESTS CROP PRODUCTION SUMMARY: According to the National Agricultural Statistics Service, there were 8.75 million acres of corn harvested in Nebraska in 2014 producing approximately 1.58 billion bushels of grain. The total average corn yield for Nebraska in 2014 was a record 181 bushels per acre (bu/a). Total corn yields from the previous 10 years are reported below.

NEBRASKA SOYBEAN VARIETY TESTS - 2014 - CROP PRODUCTION SUMMARY: According to the National Agricultural Statistics Service, there were 5.4 million acres of soybeans planted in Nebraska in 2014. 5.35 million acres were harvested producing around 288 million bushels. …

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 …

Studies To Characterize Heavy Metal Content And Migration From Recycled Polyethyleneterephthalate, Michael John-Ross Whitt

Master's Theses

Packaging Materials account for 31% of the world’s municipal solid waste. Agencies like the Environmental Protection Agency (EPA) and the Agency for Toxic Substances and Disease Registry (ATSDR) are pushing for the increased use of recycled thermoplastic materials. Polyethylene terephthalate (PET) is a commonly recycled thermoplastic which is used to package ready-to-eat fruits and vegetables. Most recycled polyethylene terephthalate (RPET) packaging materials contain heavy metal catalysts, the most common being antimony. The recent increased use of recycled plastic materials has been suspected as the source of increased human heavy metal exposure. In this study, cadmium, chromium, nickel, lead and antimony …

An Economic Analysis Of Wild Bee Pollination In Lowbush Blueberry Production, Francis A. Drummond

University of Maine Office of Research Administration: Grant Reports

The purpose of this project is to determine the relative economic values of wild bee pollinators and commercial honeybees in lowbush blueberry production for individual Maine farms. The lowbush blueberry requires insect pollination in order to set fruit. Most farmers rent colonies of the non-native honeybee for pollination services, but wild, native bees are also effective pollinators. This project aims to provide growers with the means to assess the pollination needs of individual fields and to understand the levels of pollination possible if honeybees are not available. In order to achieve these goals, the relative abundance and species diversity of …

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 …

Control Of Herbicide-Resistant Volunteer Corn In Herbicide-Resistant Soybean, Parminder Chahal

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

Volunteer corn is a problem weed in soybean fields because it reduces yield and seed quality, and potentially harbors insects, pests, and diseases. Several pre-packaged herbicides have been registered in soybean in recent years, but response of volunteer corn to these herbicides has not yet been documented. Therefore, the first objective of this study was to evaluate the response of glufosinate-, glyphosate-, and imidazolinone-resistant volunteer corn to 20 pre-emergence (PRE) and 17 post-emergence (POST) soybean herbicides. The results indicated that PRE soybean herbicides partially controlled (< 80%) volunteer corn except clomazone, while acetyl CoA carboxylase (ACCase) inhibiting herbicides provided ≥ 85% control. Germination and emergence are critical stages in weed seed establishment and persistence. Scientific literature is not available about the factors affecting germination and emergence of volunteer corn. The second objective was to determine the effects of different environmental and agronomic factors on the germination and emergence of glyphosate-resistant hybrid and volunteer corn. The results indicated that response of hybrid and volunteer corn to majority of the variables tested was similar, suggesting that volunteer corn can germinate and emerge in a wide range of climatic conditions. Majority of growers control volunteer corn when it is visible above the soybean canopy, but this can results in early season competition with soybean. The third objective was to evaluate the impact of different densities of glyphosate-resistant volunteer corn at different control timings, and late season volunteer corn emergence on soybean yields. Late season volunteer corn emergence had no significant effect on soybean yield. Yield did not decrease with all volunteer corn densities, except with the highest density (10,000 plants and 500 clumps ha^-1) at all control timings. Soybean growers are looking for alternative herbicides, such …

Economic Contribution Of Agriculture And Food To Arkansas' Gross Domestic Product 1997-2012, Leah English, Jennie Popp, Wayne Miller

Research Reports and Research Bulletins

Agricultural production, processing, and retail industries are major contributors to the Arkansas economy in terms of GDP. Agriculture contributes to the economy through direct agricultural production, value-added processing, and agricultural retail activities, and it also plays an important role through its interactions with other sectors. The use of non-agricultural goods and services as inputs into the agricultural sector promotes diversified growth in Arkansas’ economy; thus agriculture remains a vital part of Arkansas’ economy. This report: 1) compares the relative size of the Agriculture and Food Sector in Arkansas with those of neighboring states, the Southeastern region of the United States, …

The Effect Of A Small Ruminant Farm Operation And Sustainable Farm Practices: Soil Quality And Run-Off At The University Hickory Hill Farm, Delaware, Gulnihal Ozbay Dr., Akida J. Ferguson, Raju Khatiwada, Lathadevi K. Chintapenta

Professional Agricultural Workers Journal

This project was designed to evaluate the effect of ruminant grazing practices at Hickory Hill Farm on the surrounding environment by measuring soil nutrients and runoff chemistry. Three pastures on the farm (Goat, Cattle and Control) were selected for soil sampling and nutrient analyses were recorded. Physical water quality parameters were conducted on the runoff collected from the farm after Hurricane Sandy. The sites with animal activity had higher levels of sulfate, phosphate, nitrate, Mehlich 3 phosphorus and conductivity when compared to control site. However, the control site had slightly higher pH and chloride levels. Nitrogen and phosphorous levels were …

Economic Contribution Of The Agricultural Sector To The Arkansas Economy In 2012, Leah English, Jennie Popp, Wayne Miller

Research Reports and Research Bulletins

This report is the ninth in a series of reports examining agriculture’s economic contribution on the Arkansas economy. Utilizing data from the United States Bureau of Economic Analysis (BEA), USDA Economic Research Service (ERS), USDA National Agricultural Statistics Service (NASS), and IMPLAN Group, LLC , the economic contribution of agriculture on the Arkansas economy was estimated for the most recent year available, 2012.

The Trehalose Pathway In Maize: Conservation And Gene Regulation In Response To The Diurnal Cycle And Extended Darkness, Clémence Henry, Samuel W. Bledsoe, Allison Siekman, Alec Kollman, Brian M. Waters, Regina Feil, Mark Stitt, L. Mark Lagrimini

Department of Agronomy and Horticulture: Faculty Publications

Energy resources in plants are managed in continuously changing environments, such as changes occurring during the day/night cycle. Shading is an environmental disruption that decreases photosynthesis, compromises energy status, and impacts on crop productivity. The trehalose pathway plays a central but not well-defined role in maintaining energy balance. Here, we characterized the maize trehalose pathway genes and deciphered the impacts of the diurnal cycle and disruption of the day/night cycle on trehalose pathway gene expression and sugar metabolism. The maize genome encodes 14 trehalose-6-phosphate synthase (TPS) genes, 11 trehalose-6-phosphate phosphatase (TPP) genes, and one trehalase gene. Transcript abundance of most …

Msh1-Induced Non-Genetic Variation Provides A Source Of Phenotypic Diversity In Sorghum Bicolor, Roberto De La Rosa Santamaria, Mon-Ray Shao, Guomei Wang, David O. Nino-Liu, Hardik Kundariya, Yashitola Wamboldt, Ismail M. Dweikat, Sally Ann Mackenzie

Department of Agronomy and Horticulture: Faculty Publications

MutS Homolog 1 (MSH1) encodes a plant-specific protein that functions in mitochondria and chloroplasts. We showed previously that disruption or suppression of the MSH1 gene results in a process of developmental reprogramming that is heritable and non-genetic in subsequent generations. In Arabidopsis, this developmental reprogramming process is accompanied by striking changes in gene expression of organellar and stress response genes. This developmentally reprogrammed state, when used in crossing, results in a range of variation for plant growth potential. Here we investigate the implications of MSH1 modulation in a crop species. We found that MSH1-mediated phenotypic variation in Sorghum bicolor …

Cold Frames, High Tunnels, And Greenhouses: Choose A Growing Structure Best For You, Stacy A. Adams, Kim A. Todd

Department of Agronomy and Horticulture: Faculty Publications

Cold frames, high tunnels, and greenhouses are plant growth structures that can be used to extend the growing season or allow for use year around for growing high value specialty crops. This publication discusses the various attributes and applications of each so that plant producers in teaching, research, extension, commercially or as a hobby can determine the best structure to meet individual needs.

Cold frames, high tunnels, and greenhouses are structures that provide hobbyists and growers with options for plant protection and season extension. They vary in cost, size, structural complexity, and ability for year-round usage. The small cold frame …

Contrasting Metabolism In Perenniating Structures Of Upland And Lowland Switchgrass Plants Late In The Growing Season, Nathan Palmer, Aaron J. Saathoff, Christian M. Tobias, Paul Twigg, Yuannan Xia, Kenneth P. Vogel, Soundararajan Madhavan, Scott E. Sattler, Gautam Sarath

Department of Agronomy and Horticulture: Faculty Publications

Background: Switchgrass (Panicum virgatum L.) is being developed as a bioenergy crop for many temperate regions of the world. One way to increase biomass yields is to move southern adapted lowland cultivars to more northern latitudes. However, many southerly adapted switchgrass germplasm can suffer significant winter kill in northerly climes.

Materials and Methods: Here, we have applied next-generation sequencing in combination with biochemical analyses to query the metabolism of crowns and rhizomes obtained from two contrasting switchgrass cultivars. Crowns and rhizomes from field-grown lowland (cv Kanlow) and upland (cv Summer) switchgrass cultivars were collected from three randomly selected post-flowering …

Fall Seed Guide 2014, Teshome Regassa, P. Stephen Baenziger, Greg Kruger, Dipak Santra

Department of Agronomy and Horticulture: Faculty Publications

Crops include in this guide are winter wheat, winter barley, and triticale. You may receive this guide in the mail or through the University of Nebraska Extension network. The data and other information this guide is based on can be found at our web site: http://cropwatch.unl.edu/ varietytest/ and http://digitalcommons.unl.edu/ncia. Additional information is available at the wheat variety virtual tour web site http://cropwatch.unl.edu/wheat/virtual or the winter wheat variety selection tool page http://citnews.unl.edu/winter_wheat_tool/index.shtml.

Our rainfed plots in Keith County were lost to hail damage. Last season we had moist soil conditions at planting for the majority of the locations. There was good …

Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Infiltration and runoff are hydrologic processes that effect the amount of water available to plants, for groundwater recharge, and for stream flow. No-till planting (NT) is a management practice used to reduce soil erosion, increase water infiltration, and reduce soil water evaporation, and can have great impact on infiltration and runoff. An investigation was conducted to determine the impact of NT on infiltration and runoff when compared to tilled conditions.

Runoff and precipitation data was gathered from sites at Fillmore County, NE, Phelps County, NE, the USDA-ARS North Appalachian Experimental Watersheds (NAEW) near Coshocton, OH, and the Lennoxville Research Station …

Selection On Crop-Derived Traits And Qtl In Sunflower (Helianthus Annuus) Crop-Wild Hybrids Under Water Stress, Birkin R. Owart, Jonathan Corbi, John M. Burke, Jennifer M. Dechaine

All Faculty Scholarship for the College of the Sciences

Locally relevant conditions, such as water stress in irrigated agricultural regions, should be considered when assessing the risk of crop allele introgression into wild populations following hybridization. Although research in cultivars has suggested that domestication traits may reduce fecundity under water stress as compared to wild-like phenotypes, this has not been investigated in crop-wild hybrids. In this study, we examine phenotypic selection acting on, as well as the genetic architecture of vegetative, reproductive, and physiological characteristics in an experimental population of sunflower crop-wild hybrids grown under wild-like low water conditions. Crop-derived petiole length and head diameter were favored in low …

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 …

Management Of Root Knot Nematode (Meloidogyne Incognita ) In Indiana Soybeans, David Edgardo Perla Martinez

Open Access Theses

The aim of this project was to evaluate different strategies for management of Root Knot Nematode (RKN) on soybean and tomato in Indiana. Seed treatments were evaluated under field and greenhouse conditions, but no effect on RKN populations was observed. Soybean lines evaluated for resistance to RKN under greenhouse conditions showed that six lines may be resistant to RKN. Four different commercial mustard cover crops were evaluated for their bio-fumigant impact on RKN populations in the production of tomato. Euruca sativa, Cv. Nemat was a poor host of RKN. A positive impact on the vigor of the tomato plants followed …

Ems Induced Mutations In Dhurrin Metabolism And Their Impacts On Sorghum Growth And Development, Jenae Lavon Skelton

Open Access Theses

Sorghum is the fifth most important grain crop in the world. It is a staple food, feed, and silage crop in many developing countries in the semi-arid tropics. One factor that can impact sorghum forage quality is dhurrin content. Dhurrin is a cyanogenic glucoside naturally produced in the plant. When tissues containing dhurrin are crushed, hydrogen cyanide (HCN) is released during dhurrin decomposition. HCN is toxic to humans and livestock. While there is natural genetic diversity for the concentration of dhurrin within sorghum lines, there have been no naturally occurring dhurrin-free genotypes identified to date. ^ We have identified ethyl …

Fact Or Fiction: Random Mating In Field Populations Of Western Corn Rootworm (Diabrotica Virgifera Virgifera Leconte) Emerging On Bt And Refuge Corn Plants, Steven Joel Smith

Open Access Theses

The western corn rootworm, or WCR, (Diabrotica virgifera virgifera LeConte) is the most significant pest of field corn (Zea mays) in the United States, and has recently expanded its range into Europe. Since 2004, hybrid corn containing Bt toxins targeting the corn rootworm complex have been heavily adopted and are now the primary control measure for this pest in North American corn production. ^ The evolution of resistance is an ongoing concern, and to ensure Bt products will retain their usefulness, insect resistance management (IRM) tactics using various refuge structures have been adopted. One of the key …

Functional Genomics Of Maize Endosperm Maturation And Protein Quality, Lingling Yuan

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

Maize is one of the most important cereal crops and widely cultivated throughout the world. The study on maize kernel development including protein quality improvement is essential for removing dietary protein deficiency because of the lack of essential amino acids, especially lysine and tryptophan, in maize kernel. Quality Protein Maize (QPM) is a hard kernel variant of the high-lysine mutant, opaque-2. We created opaque QPM variants to identify opaque-2 modifier genes and to investigate deletion mutagenesis combined with Illumina sequencing as a maize functional genomics tool. A K0326Y-QPM deletion mutant, line 107, was null for the 27- and 50-kD …

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 …

Economic Contribution Of Agriculture And Food To Arkansas' Gross Domestic Product 1997-2011, Jacob Manlove, Leah English, Jennie Popp, Wayne Miller

Research Reports and Research Bulletins

Agricultural production, processing, and retail industries are major contributors to the Arkansas economy in terms of GDP. Agriculture contributes to the economy through direct agricultural production, value-added processing, and agricultural retail activities, and it also plays an important role through its interactions with other sectors. The use of non-agricultural goods and services as inputs into the agricultural sector promotes diversified growth in Arkansas’ economy; thus agriculture remains a vital part of Arkansas’ economy. Part 1 of the report compares the relative size of the Agriculture and Food Sector in Arkansas with those of neighboring states, the Southeastern region of the …

Drivers Of Spatial And Temporal Variation In Soybean Yield And Irrigation Requirements In The Western Us Corn Belt, Patricio Grassini, Jessica A. Torrion, Kenneth Cassman, Haishun Yang, James Specht

Department of Agronomy and Horticulture: Faculty Publications

Both rainfed and irrigated soybean production are important in Nebraska (western US Corn Belt), accounting for a respective 48 and 52% of the state’s soybean production of 7 Mt on a respective 55 and 45% share of the state soybean area of 1.9 Mha. To date, no assessment of factors that may account for regional and inter-annual variation in yield and irrigation amount has been performed. To accomplish that objective, we evaluated a database containing on-farm field yields and total irrigation amount used in those fields. These data have been collected annually from ca. 1000 soybean fields in six regions …

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 …

Spreading The Char: The Importance Of Local Compatibility In The Diffusion Of Biochar Systems To The Smallholder Agriculture Community Context, Laura C. V. Munoz

Pomona Senior Theses

This thesis enters the context of smallholder agriculture communities in the developing world. It explores the potentials of biochar and what biochar systems could bring to the smallholder communities while simultaneously bringing environmental benefits. It then acknowledges the challenges of diffusion –the spreading of an unfamiliar innovation. It seeks to answer the question of what will make diffusion of biochar systems more successful in the smallholder context, fixating on the characteristic of compatibility as well as the role local community members can play in making a new biochar system more visible to the rest of the communities.

Overview Of The Integrated Pest Management (Ipm) Terrain And Activities In Furtherance Of The Walmart Initiative To Purchase Fresh Vegetables From Local Growers In Alabama, Franklin Quarcoo, Conrad Bonsi

Professional Agricultural Workers Journal

Tuskegee University has been providing various types of technical expertise to limited resource farmers who have been supplying Walmart with collard greens, watermelons and purple hull peas. A number of pests bedevil the cultivation of these crops; cost-effective management methods for these pests are needed. The objectives of this paper are to document the IPM activities associated with supplying produce to Walmart; summarize pest problems encountered on the afore-stated crops; recommend IPM methods suitable for limited resource farmers; and suggest other activities that ensure that farmers incur even less pest-related crop losses. Anthracnose was the major pest encountered on watermelons. …

Nitrogen Rate Optimization For Grain Yield Within Fall And Spring Applications, Justin Wheeler

Theses and Dissertations

This thesis is a comprehensive analysis of research, investigating the impact of fall and spring applied nitrogen at various rates on the vulnerability of fall applied nitrogen, nitrogen uptake, and corn yields. In addition, optimal nitrogen rates and timing were evaluated across East Central Illinois.

Effect Of Aquafeed On Productivity Of Red Amaranth And On Water Quality Under Aquaponic Cultivation, Miles D. Medina

FIU Electronic Theses and Dissertations

Aquaponics, the integrated production of fish and hydroponic crops in a recirculating system, is an intensive cultivation method in which metabolic fish wastes fertilize plants. This study compares the effects of two aquafeeds on Red amaranth (Amaranthus tricolor) productivity and on water quality under cultivation of Blue tilapia (Oreochromis aureus), with three aquaponic units (n=3) per treatment over a 60-day trial. The fishmeal-based control feed contains higher crude protein (40%) and phosphorus (1.12%) than the plant-based alternative feed (32% and 0.40%). The alternative feed resulted in a significantly higher amaranth crop yield (p