Agriculture Commons^™

Roles Of Peroxisomes And Peroxisome-Derived Products In Controlling Plant Growth And Stress Responses, Elizabeth May Frick

Arts & Sciences Electronic Theses and Dissertations

The peroxisome is a vital organelle conserved through the entire eukaryotic lineage. In all examined species, peroxisomes are responsible for such essential processes as fatty acid beta-oxidation and metabolism of reactive oxygen species (ROS). In plants, peroxisomes have taken on additional specialized roles, such as production of some plant hormones and vitamins. In this work, I have uncovered novel factors regulating peroxisome number in model species Arabidopsis thaliana, and novel mechanisms governing how peroxisomes respond to salt stress. I discovered a role for Arabidopsis MAP KINASE17 (MPK17) as a negative regulator of peroxisome division that acts in the salt-stress response …

Analysis Of Argonaute-Small Rna-Transcription Factor Circuits Controlling Leaf Development, John Steen Hoyer

Arts & Sciences Electronic Theses and Dissertations

Experimental studies of plant development have yielded many insights into gene regulation, revealing interactions between core transcriptional and post-transcriptional regulatory pathways present in all land plants. This work describes a direct connection between the three main small RNA-transcription factor circuits controlling leaf shape dynamics in the reference plant Arabidopsis thaliana. We used a high-throughput yeast 1-hybrid platform to identify factors directly binding the promoter of the highly specialized ARGONAUTE7 silencing factor. Two groups of developmentally significant microRNA-targeted transcription factors were the clearest hits from these screens, but transgenic complementation analysis indicated that their binding sites make only a small contribution …

Economic Contribution Of The Agricultural Sector To The Arkansas Economy In 2015, Leah English, Jennie Popp, Wayne Miller

Research Reports and Research Bulletins

Agriculture and associated agricultural activities are major contributors to the Arkansas economy. Agriculture is defined as the sum of agricultural production and processing activities, unless otherwise specified, and includes crop and animal production and processing, agricultural support industries, forestry and forest products, and textile goods. Agriculture contributes to the economy through direct agricultural production and value-added processing, and also leads to economic activity in other parts of the economy. This report is the tenth in a series of reports examining agriculture’s economic contribution to the Arkansas economy. The total economic contribution of agriculture (direct, indirect, and induced effects) on value …

In The Field The Women Saved The Crop: The Women’S Land Army Of World War Ii, Denna M. Clymer

Graduate Theses and Dissertations

The Women’s Land Army brought together rural and urban sectors of the United States in a climate of national and regional crisis. By the time the country was cast into war, the agricultural sector was already caught in a downward economic spiral that drove away laborers. With demand falling, and farms propped up only by experiments in subsidy and parity, when military and industrial jobs emerged in urban areas, farm laborers became scarce. At the same time the war created jobs for men outside of the agricultural sector, farm prices recovered and demand soared, forcing farmers to look to women …

Evaluation Of Insecticide Seed Treatments To Protect Rice (Oryza Sativa) Against Various Herbicides, Steven Michael Martin

Graduate Theses and Dissertations

The increase in herbicide-resistant weeds in Arkansas crop fields has led to the need for new herbicide modes of action for use in all crops. This need has led to the introduction of technologies that can be devastating to conventional rice crops. Field observation, noted that insecticide seed treatments used in rice could potentially reduce the effects of off-target movement of herbicides onto rice crops and possibly reduce the negative effects of some herbicides applied directly to rice. Research was conducted to determine if insecticide seed treatments could reduce the harmful effects of drift from imazethapyr and glyphosate onto conventional …

Oystershell Scale Impacts And Mitigation Options On The Kaibab And Coconino Nf’S, Amanda M. Grady

Aspen Bibliography

This report documents a site visit to evaluate aspen stands experiencing oystershell scale damage on the Kaibab and Coconino National Forest’s. The site visit was requested by Kaibab NF, foresters including; Josh Giles, Jessi Outzs, Michael Sedgeman, Woody Rokala and Coconino Silviculturist, Mark Nabel. On November 19, 2016, Amanda Grady accompanied the individuals listed above, to evaluate stand conditions within three aspen exclosures. Two were located on the Williams Ranger District, Kaibab NF in the vicinity of Spring Valley. The third exclosure was located on the Flagstaff RD, Coconino NF and accessed from HWY 89-A via the Pump House Wash …

Economic Impact Of The Sugarcane Aphid Outbreak In South Texas, Samuel D. Zapata, Rebekka Dudensing, Danielle Sekula, Gabriela Esparza-Díaz, Raul Villanueva

Entomology Faculty Publications

The objective of this study was to estimate the economic impact of the sugarcane aphid (SCA) outbreak in the Rio Grande Valley (RGV), Texas. Local producers were surveyed to gather detailed information about crop production and pest control practices. Collected data were used to estimate the reduction in profit associated with the SCA infestation, as well as the monetary value of the prevented loss attributed to control efforts. Sorghum industry losses were then used to assess the overall economic impact of the SCA outbreak in the RGV economy.

Evaluating The Impact Of Two Contrasting Tillage Practices On Soil Properties In Central Kentucky, Emily Cook

Posters-at-the-Capitol

Farming practices such as no tillage and plowing can institute change on soil physical and chemical characteristics. In this research, the effects of long-term conventional and no-tillage systems on the selected soil properties were determined in a continuous corn system on a farm with Maury silt loam soil. These samples were taken from University of Kentucky's Research Farm (Spindletop Farm). The field used was tilled in 1969 from bluegrass sod and the first time research was conduced was in 1970. Each plot is 20 ft. by 40 ft. and for many years each plot was split with winter cover crop …

Characterization Of Aspergillus Flavus Soil And Corn Kernel Populations From Eight Mississippi River States, Jorge A. Reyes Pineda

LSU Master's Theses

Aspergillus flavus is a saprophytic ascomycete that can also actively invade the seed of crops and potentially contaminate them with harmful aflatoxins. Management of A. flavus currently relies mostly on biocontrol. However, there is still a lot to learn about its biology and ecology so the current approach can be improved. An A. flavus population survey was undertaken during the fall of 2014 across eight Mississippi River states to determine population diversity and geographic distribution of VCGs. Isolates from corn and soil were also characterized for VCG, sclerotial morphotype, mating type, cyclopiazonic acid, and aflatoxin production in order to determine …

Climate Change And Food Systems: Assessing Impacts And Opportunities, Meredith T. Niles, Richie Ahuja, Jimena M. Esquivel, Nelson Mango, Mil Duncan, Martin Heller, Cristina Tirado

College of Agriculture and Life Sciences Faculty Publications

No abstract provided.

Grains, Seeds And Hay Industry Funding Scheme Annual Report 2016/2017, Department Of Primary Industries And Regional Development, Western Australia

Biosecurity published reports

The Grains, Seeds and Hay Industry Funding Scheme (IFS) has been operating since 2010 to address biosecurity threats relevant to Western Australia’s (WA) grains, seeds and hay industry. The Scheme was established under the Biosecurity and Agriculture Management Act 2007 to enable growers to identify the pest and disease priorities at a whole-of-industry level and raise funds for activities to address these priorities.

There are currently three Industry Funding Schemes in operation. In addition to the Grains, Seeds and Hay IFS, there is a Cattle IFS and a Sheep and Goat IFS. The three IFSs operate in a similar manner. …

Peel Business Park Transition Strategy, Ghd

Natural resources commissioned reports

Transform Peel

Transform Peel is a $49m Royalties for Regions funded program aimed at achieving job creation, sustainable growth and economic development in the Peel Region. The Peel Development Commission and its partners, intend to implement this program over 35 years where projections estimate that 35,000 jobs will be created generating an approximate $16.2b per annum economic output by 2050. Located in the Shires of Murray and Serpentine Jarrahdale, the program comprises three integrated, strategic elements, the Peel Business Park (PBP), the Peel Food Zone (PFZ) and the Peel Integrated Water Initiative.

The Department of Primary Industries and Regional Development …

Influence Of An Internal Parasite Control On Cattle Grazing Behavior And Production, Jace Stott

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

Six herds of 45 to 90 cow/calf pairs grazing on upland range were used to examine the efficacy of an injectable extended release eprinomectin parasite control on production traits, activity behavior, and efficacy against internal parasitism. In 2016, treatment cows were given a subcutaneous injection of LongRange^tm. In 2017, all cows in the study were treated with a short acting Synanthic^tm treatment and only treatment cows were given an additional LongRange^tm treatment. In both 2016 and 2017, fecal egg counts were significantly lower (P < 0.05) in eprinomectin treated cows compared to control cows. Calf gains were 4.8 kg and 8.7 kg greater (P < 0.1) for the calves of dams treated with eprinomectin compared to calves of control cows in 2016 and 2017, respectively. Activity characteristics of cattle were inconclusive, with treated cows having lower (P < 0.01) grazing and traveling times compared to control cows in 2016, and more (P < 0.01) grazing and traveling in 2017.

Differences in grazing behaviors based on time within pasture at different times …

Impact Of Automated Guidance For Mechanical Control Of Herbicide-Resistant Weeds In Corn, Terry Griffin, James M. Lowenberg-Deboer

Journal of Applied Farm Economics

This study evaluated the feasibility of reintroducing mechanical weed control as an alternative for herbicide-resistance weed infestations. The production practice tested included row cultivation with a separate banded spray application using high-accuracy automated guidance systems. A range of ground speeds were tested for the row cultivation operation, each with a different per acre cost and timeliness penalty. A typical eastern Corn Belt farm with a rotation of corn and soybean served as the base for the linear programming model. It was found that if the farmer was willing to reintroduce tillage, row cultivation conducted at higher operating speeds in conjunction …

Substantial Contribution Of Genetic Variation In The Expression Of Transcription Factors To Phenotypic Variation Revealed By Erd-Gwas, Hung-Ying Lin, Qiang Liu, Xiao Li, Jinliang Yang, Sanzhen Liu, Yinlian Huang, Michael J. Scanlon, Dan Nettleton, Patrick S. Schnable

Department of Agronomy and Horticulture: Faculty Publications

Background: There are significant limitations in existing methods for the genome-wide identification of genes whose expression patterns affect traits.

Results: The transcriptomes of five tissues from 27 genetically diverse maize inbred lines were deeply sequenced to identify genes exhibiting high and low levels of expression variation across tissues or genotypes. Transcription factors are enriched among genes with the most variation in expression across tissues, as well as among genes with higher-than-median levels of variation in expression across genotypes. In contrast, transcription factors are depleted among genes whose expression is either highly stable or highly variable across genotypes. We developed a …

Estimation Of Irrigation Requirements For Drip-Irrigated Maize In A Sub-Humid Climate, Liu Yang, Hai-Shun Yang, Jiu-Sheng Li, Yan-Feng Li, Hai-Jun Yan

Department of Agronomy and Horticulture: Faculty Publications

Drip-irrigation is increasingly applied in maize (Zea mays L.) production in sub-humid region. It is critical to quantify irrigation requirements during different growth stages under diverse climatic conditions. In this study, the Hybrid-Maize model was calibrated and applied in a sub-humid Heilongjiang Province in Northeast China to estimate irrigation requirements for drip irrigated maize during different crop physiological development stages and under diverse agro-climatic conditions. Using dimensionless scales, the whole growing season of maize was divided into diverse development stages from planting to maturity. Drip-irrigation dates and irrigation amounts in each irrigation event were simulated and summarized in 30-year simulation …

Identifying Ecologically Relevant Scales Of Habitat Selection: Diel Habitat Selection In Elk, Caleb P. Roberts, James W. Cain Iii, Robert D. Cox

Department of Agronomy and Horticulture: Faculty Publications

Although organisms make resource selection decisions at multiple spatiotemporal scales, not all scales are ecologically relevant to any given organism. Ecological patterns and rhythms such as behavioral and climatic patterns may provide a consistent method for identifying ecologically relevant scales of habitat selection. Using elk (Cervus canadensis) as an example species, we sought to test the ability of behavioral patterns to empirically partition diel scales for modeling habitat selection. We used model selection to partition diel scales by shifts in dominant behavior and then used resource selection probability functions to model elk habitat selection hierarchically at diel scales within seasons. …

Effects Of Nitrogen And Phosphorus Fertilizer And Topsoil Amendment On Native Plant Cover In Roadside Revegetation Projects, Heidi L. Hillhouse, Walter H. Schacht, Jonathan M. Soper, Carol E. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Establishing vegetation on roadsides following construction can be challenging, especially for relatively slow growing native species. Topsoil is generally removed during construction, and the surface soil following construction (“cut-slope soils”) is often compacted and low in nutrients, providing poor growing conditions for vegetation. Nebraska Department of Transportation (NDOT) protocols have historically called for nitrogen (N) and phosphorus (P) fertilization when planting roadside vegetation following construction, but these recommendations were developed for cool-season grass plantings and most current plantings use slower-establishing, native warmseason grasses that may benefit less than expected from current planting protocols. We evaluated the effects of nitrogen and …

Recognizing Challenges And Opportunities In The Quest To End Hunger, Jennifer Williams Zwagerman

Texas A&M Law Review

As an attorney and professor that does not focus on intellectual property law, I was a bit apprehensive about providing a keynote address for a Symposium focusing on “Agriculture, Intellectual Property, and Feeding the World in the 21st Century.” As I thought about this topic, knowing that there were other speakers who would focus more on the IP issues and technical aspects of various topics, I kept coming back to the importance of technology as we worktowards the goal of feeding the world, and the many ways in which innovation plays a role in meeting that goal. It also brought …

The Gmo/Ge Debate, Joanna K. Sax

Texas A&M Law Review

We live longer and healthier lives because advances in science create easier and better ways to sustain and survive. Society has an intricate relationship with biotechnology. Vaccines save lives. Fluoridated water decreases dental issues. Antibiotics treat bacterial infections. Nuclear power is a form of clean energy. With any emerging technology, the benefits do not exist in a vacuum, thus, negative consequences result as well. Our widespread uses of antibiotics are creating antibiotic-resistant strains of bacteria. Our research into nuclear energy also facilitated the creation of nuclear bombs. Perhaps it is human nature to use scientific advances for good and for …

Managing Nitrous Oxide Emissions In Agricultural Fields, Mark S. Coyne, Wei Ren

Plant and Soil Sciences Research Report

Agriculture is a major contributor to atmospheric nitrous oxide (N₂O) (Smith et al., 2014; Tian et al., 2015). Unfortunately, nitrous oxide destroys stratospheric ozone (O₃) which protects us from ultraviolet radiation (Cicerone, 1989) and it increases ground level O_3, whichis an air pollutant threatening human health and food production. Nitrous oxide is also 298 times more potent than an equivalent amount of carbon dioxide (CO₂) in terms of trapping and absorbing reflected solar radiation (Forster et al., 2007). Basic chemistry and physics assure us that increased levels of N₂O in the …

Economies Of Scale In Integrated Pest Management In Vegetable And Fruit Production, Franklin Quarcoo, Conrad Bonsi, David Nii O. Tackie, Walter A. Hill, Gertrude Wall, George Hunter

Professional Agricultural Workers Journal

Abstract

Pest management is achieved directly using a variety of tools, including pesticides, and indirectly through a number of agronomic/cultural practices such as irrigation and fertilizer application; collectively these practices function to positively effect general plant health. Healthier plants are more resistant to or tolerant of pests. This study explores the scale differences that impact the pest management significance and suitability of certain agronomic practices. Scale differences were discussed using literature-based information, direct field observations, and anecdotal information on the relative advantages of drip and sprinkler irrigation systems; organic and conventional cultivation of crops; crop rotation versus mono-cropping systems; precision …

Control Of Glyphosate-Resistant Common Ragweed (Ambrosia Artemisiifolia L.) In Glufosinate-Resistant Soybean [Glycine Max (L.) Merr], Ethann R. Barnes, Stevan Z. Knezevic, Peter H. Sikkema, John L. Lindquist, Amit J. Jhala

Department of Agronomy and Horticulture: Faculty Publications

Common ragweed emerges early in the season in Nebraska, USA and is competitive with soybean; therefore, preplant herbicides are important for effective control. Glyphosate has been used as a preplant control option; however, confirmation of glyphosate-resistant (GR) common ragweed in Nebraska necessitates evaluating other herbicide options. The objectives of this study were to (1) evaluate the efficacy of preplant (PP) herbicides followed by (fb) glufosinate alone or in tank-mixture with imazethapyr, acetochlor, or S-metolachlor applied post-emergence (POST) for control of GR common ragweed in glufosinate-resistant soybean; (2) their effect on common ragweed density, biomass, and soybean yield; and (3) the …

Applying Biodiversity And Ecosystem Function Theory To Turfgrass Management, Grant L. Thompson, Jenny Kao-Kniffin

Grant Thompson

Pinching And Spacing Effects On Cut Sunflower (Helianthus Annuus) Production In East Texas, Rebecca B. Burnett

Electronic Theses and Dissertations

Three experiments evaluated pinching and spacing on Helianthus annuus in East Texas to determine their effects on growth and development. Experiment 1 was designed to determine the effects of pinching nodes 1, 2, 3, or 4 on ‘Pro Cut Gold’ sunflowers. Results from experiment 1 showed non-pinched plants produced marketable stem lengths and flower sizes, while pinched plants’ stem length, stem diameter, flower diameter, and disk diameter decreased compared to the non-pinched plants. The objective for experiment 2 was to evaluate pinching and spacing treatments on ‘Pro Cut Gold’ sunflowers. All spacings for non-pinched plants in experiment 2 produced marketable …

Impact Of Seed Protein Alleles From Three Soybean Sources On Seed Composition And Agronomic Traits, Lillian F. Brzostowski, Timothy I. Pruski, James Specht, Brian W. Diers

Department of Agronomy and Horticulture: Faculty Publications

Evaluation of seed protein alleles in soybean populations showed that an increase in protein concentration is generally associated with a decrease in oil concentration and yield.

Soybean [Glycine max (L.) Merrill] meal is one of the most important plant-based protein sources in the world. Developing cultivars high in seed protein concentration and seed yield is a difficult task because the traits have an inverse relationship. Over two decades ago, a protein quantitative trait loci (QTL) was mapped on chromosome (chr) 20, and this QTL has been mapped to the same position in several studies and given the confirmed QTL …

Impact Of Nitrogen Application Timing On Corn Production, John E. Sawyer, Daniel W. Barker, John P. Lundvall

John E. Sawyer

Water quality issues have renewed interest in timing of nitrogen (N) application as a means to improve use efficiency in corn and reduce losses. Improved economic return is also desired as N fertilization is one of the most costly inputs to corn production. Time of fertilizer application is a component of the site-specific 4R nutrient management stewardship programs. In Iowa, the Nutrient Reduction Strategy has a 7% (37% std. dev.) nitrate-N reduction with a 0% (3% std. dev.) corn yield change for sidedress compared to pre-plant N application (SP 0435A).

Crop Responses To Amisorb In The North Central Region, Sylvie Brouder, Robert Dowdy, Dave Franzen, Gary Hergert, Robert Hoeft, Maurice Horton, Keith Kelling, David Mengel, George Rehm, John Sawyer, Peter Scharf, Darryl Warnacke, David Whitney

John E. Sawyer

Originally used to prevent scale in boilers, carpramid or thermal polyaspartate (copoly[(3-carboxypropionamide)( 2-carboxylmethyl) acetamide)] was brought to agriculture under the trade names AmiSorb and Magnet. It claimed to increase nutrient uptake through artificially increasing the volume of soil occupied by roots through increased root branching and root hair development. Under controlled hydroponic or greenhouse conditions, the use of carpramid increased nutrient uptake, some yield determining factors such as wheat tillering and in some cases, crop yield. Extensive field testing from 1996 to 1998 under various nutrient regimes, placements, forms, and timings resulted in very inconsistent performance. Averaged across all experiments …

Nitrogen Fertilizer Rate Effects On Soil Organic Carbon In Iowa Continuous Corn And Corn-Soybean Systems, Hanna J. Poffenbarger, Daniel W. Barker, Matthew J. Helmers, Fernando E. Miguez, John E. Sawyer, Johan Six, Michael J. Castellano

John E. Sawyer

Nitrogen fertilizer rate is a key factor affecting soil organic C (SOC) in corn-based cropping systems. The objective of this study was to determine the change in SOC in response to long-term N rates for continuous corn and corn-soybean cropping systems at two sites in Iowa. Soil samples were collected to a depth of 15 cm in 1999 and again in 2014 after 15 years of corn N rate treatments ranging from 0 to 269 kg ha^-1. The soil samples were analyzed for total C and N concentrations. For continuous corn at both sites, the average annual change …

Ecological And Organic Life Safety Concerns Of Hfo-1234yf, Alberni V. Ruiz

STAR Program Research Presentations

While at NOAA my research was directed by the inquiry of whether or not HFO-1234yf, a new compound being introduced into coolant system and replacing greenhouse gases HFC, is harmful to organic life. Using the computer program Matlab I was able to develop figures that represented the concentration of HFO-1234yf (HFO) in 12 different tower locations throughout the country. Comparing and contrasting concentrations of this HFO compound at each site led me to the question the possible harmful side effects this compound could bring to organic life due to the fact that concentration levels are increasing, with one factor being …