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The Effect Of Year-To-Year Variability On Planting Date And Relative Maturity Selection For Maize, Mitch Baum Jan 2019

The Effect Of Year-To-Year Variability On Planting Date And Relative Maturity Selection For Maize, Mitch Baum

Graduate Theses and Dissertations

Current maize (Zea mays L.) planting date recommendations have not been updated in the state of Iowa since 2001. A state that produced 68.8 million tons of maize on 5.5 million hectares in 2016. It is imperative that this information be regularly updated as both climate and maize hybrid selection are constantly changing. We analyzed maize yield and phenology, from a multi-location, year, relative maturity (RM), and planting date (PD) experiment carried out in Iowa, US. The dataset was used to calibrate a site-specific model (Agricultural Production System sIMulation, APSIM) and extrapolate APSIM results across Iowa, using a ...


Uhf Band Attenuation Through A Corn Canopy With Crop Growth, Richard Jay Cirone Jan 2019

Uhf Band Attenuation Through A Corn Canopy With Crop Growth, Richard Jay Cirone

Graduate Theses and Dissertations

Soil moisture and vegetation remote sensing measurements can be inaccurate and/or misinterpreted in the US Corn Belt, specifically when considering seasonal variation in standing vegetation. A direct crop water measurement method was employed to assist in correction of satellite measurements, specifically to SMOS and SMAP. A 433 MHz radio link was installed in a central Iowa cornfield, shortly after planting, across a distance of 50 meters, for the purpose of measuring attenuation by crop water. This experiment ran until mid grain fill, development stage R3. Vegetation water column density increased from essentially 0 at planting to just above 4 ...


A Statistical Analysis Of Zea Mays Grain Yield Response To Nitrification-Inhibitor Amendments Under Field Conditions Utilizing Parametric And Non-Parametric Techniques, Elliot H. Sully Jan 2019

A Statistical Analysis Of Zea Mays Grain Yield Response To Nitrification-Inhibitor Amendments Under Field Conditions Utilizing Parametric And Non-Parametric Techniques, Elliot H. Sully

Graduate Theses and Dissertations

Nitrification is a matter of economic and ecological importance in nitrogen-tensive agricultural practices such as corn (Zea mays) grain production. When ammonium is bacterially oxidized into nitrate it becomes more susceptible to leaching and denitrification as nitrous oxide. The nitrification process not only adds to water and air pollution but also impacts on farm productivity by reducing grains yields and increasing fertilizer demands. Nitrification inhibiting fertilizer amendments can potentially improve grain yields by retarding the growth of nitrifying soil bacteria. Multiple field studies conducted across various locations and timespans have generated mixed results regarding the grain yield difference attributed to ...


Segregation Strategies For Non-Gm Corn: Improving Effectiveness Through An Analytical Modeling Approach, Chad Joseph Dolphin Jan 2019

Segregation Strategies For Non-Gm Corn: Improving Effectiveness Through An Analytical Modeling Approach, Chad Joseph Dolphin

Graduate Theses and Dissertations

The open air growing environment for corn (Zea mays L.) makes it impossible to maintain genetic purity of 100%. Much debate has characterized the discussion on acceptable tolerance levels for adventitious presence to ensure coexistence between genetically modified and non-genetically modified crops. This research analyzes nine scenarios to test field, handling, and elevator-based segregation capabilities in a commodity system. Using stochastic models to model individual factors that contribute to adventitious presence in commodity maize including: impure seed, isolation distance, equipment cleanout, and elevator handling practices, Monte Carlo simulation was used to calculate the cumulative amount of adventitious presence for each ...


Evolution Of Soybean Weed Management In The United States, Aaron Rowe Jan 2018

Evolution Of Soybean Weed Management In The United States, Aaron Rowe

Creative Components

Weeds have been an unwanted nuisance since the beginning of agriculture. The processes and technologies utilized to manage this yield limiting problem have evolved over time. Soybean [Glycine max (L.) Merr.] production in the United States has experienced all of the major agriculture revolutions. This has included horse-drawn field implements, tractor power implementation, chemical era, and the most recent era of biotechnology. There has been a continuous gain in efficiencies with the discovery and introduction of new technologies to manage weeds in soybeans. A period of rapid discovery and introduction of new and novel herbicide sites of action (SOA) with ...


Understanding The Effects Plant Density Has On Seed Yield In Hybrid Rice Seed Production, Cody Brandl Jan 2018

Understanding The Effects Plant Density Has On Seed Yield In Hybrid Rice Seed Production, Cody Brandl

Creative Components

No abstract provided.


Investigations Into The Function Of Common Milkweed (Asclepias Syriaca) In The Agricultural Landscape, Sydney Lizotte-Hall Jan 2018

Investigations Into The Function Of Common Milkweed (Asclepias Syriaca) In The Agricultural Landscape, Sydney Lizotte-Hall

Graduate Theses and Dissertations

The monarch butterfly’s (Danaus plexippus Linnaeus) vibrant orange color with contrasting black veins and white spots make it recognizable to many. Unfortunately, the remarkable migration made by the eastern monarch population is at risk due to the recent decline in this cohort of the species. Many factors are said to have caused the decline, including overwintering habitat destruction, increased dependence on herbicide-tolerant crops, extreme climatic events, predation, loss of breeding habitat, etc.

Two studies were conducted to: 1) determine the impact of sub-lethal herbicides on growth of common milkweed and utilization by monarchs and 2) investigate simple methods for ...


Drivers Of Yield And Nitrogen-Loss Tradeoffs: Cropping System Evaluations With Process-Based Modeling, Rafael Alejandro Martinez-Feria Jan 2018

Drivers Of Yield And Nitrogen-Loss Tradeoffs: Cropping System Evaluations With Process-Based Modeling, Rafael Alejandro Martinez-Feria

Graduate Theses and Dissertations

The Midwest is one of the most productive agricultural regions, but mitigating loss of nitrogen (N) from cropland is needed to improve environmental quality. Tradeoffs between crop yield and N loss have been linked largely to the inefficient use of N fertilizers, but the contributions of more systemic factors such as soil characteristics, crop sequences, and genotypes have not been thoroughly studied. This dissertation examines and quantifies the impact of various genetic, environmental and management drivers of crop yield and N-loss tradeoffs in the maize and soybean cropping systems of the US Midwest, and identifies potential management strategies to lessen ...


Evaluating The Impacts Of Midwestern Cropping Systems On Soil Health And Subsurface Drainage Water Quality, Brian Dougherty Jan 2018

Evaluating The Impacts Of Midwestern Cropping Systems On Soil Health And Subsurface Drainage Water Quality, Brian Dougherty

Graduate Theses and Dissertations

Agricultural nutrient management practices are an important component of the effort to improve water quality in the Mississippi River Basin. In particular, there is concern about nutrient export to the Gulf of Mexico via loss from subsurface drainage systems. Optimizing the use of fertilizers and animal manures in combination with other management practices has the potential to minimize negative impacts on water quality. Farmers are increasingly challenged to maximize crop production while utilizing fertilizers and animal manures in an efficient and environmentally friendly manner. An increasing awareness of the potential to address these issues by improving soil health has also ...


The Influence Of Multiple Herbicide Resistance On Growth And Development Of Amaranthus Tuberculatus And The Efficacy Of The Very Long Chain Fatty Acid-Inhibiting Herbicides On Multiple Herbicide-Resistant Amaranthus Tuberculatus; Investigating A Putative 4-Hydroxylphenylpyruvate Dioxygenase-Inhibiti, Eric Alexander Lyle Jones Jan 2018

The Influence Of Multiple Herbicide Resistance On Growth And Development Of Amaranthus Tuberculatus And The Efficacy Of The Very Long Chain Fatty Acid-Inhibiting Herbicides On Multiple Herbicide-Resistant Amaranthus Tuberculatus; Investigating A Putative 4-Hydroxylphenylpyruvate Dioxygenase-Inhibiti, Eric Alexander Lyle Jones

Graduate Theses and Dissertations

Iowa farmers rely mainly on herbicides for weed management. Inconsistent and unsatisfactory weed control is being realized as the spread of herbicide-resistant weed populations has increased. Populations of waterhemp (Amaranthus tuberculatus (Moq.) J.D. Sauer) and giant ragweed (Ambrosia trifida L.) have evolved resistance to glyphosate and other herbicides commonly used in crop fields. This research focuses on the growth and development of multiple herbicide-resistant waterhemp and assessing the evolution of new herbicide-resistant waterhemp and giant ragweed populations.

Significant differences in growth, flowering, accumulated biomass, and seed production were detected when the multiple herbicide-resistant waterhemp populations were compared to a ...


Winter Cereal Rye And Selected Brassica Cover Crops For Forage Prior To Soybeans, Timothy James Sklenar Jan 2018

Winter Cereal Rye And Selected Brassica Cover Crops For Forage Prior To Soybeans, Timothy James Sklenar

Graduate Theses and Dissertations

Despite myriad benefits to incorporating winter cover crops into conventionally managed row crop systems farmer adoption remains low in Iowa. Commonly cited apprehensions include the costs associated with managing cover crops without any short term economic benefits and the complexities associated with management of cover crops. The management of cover crops as a forage could potentially help address both of these issues while at the same time enhancing the environmental sustainability of conventionally managed systems. The work provided in this thesis is an attempt to evaluate the potential for four selected species to be managed as dual-purpose winter cover crops ...


Genetic Dissection Of Photosynthetic Traits In Sorghum Under Cold And Drought Stress, Diego Ortiz Jan 2018

Genetic Dissection Of Photosynthetic Traits In Sorghum Under Cold And Drought Stress, Diego Ortiz

Graduate Theses and Dissertations

Sorghum (Sorghum bicolor L. Moench) is one of the most important cereal crops cultivated in arid and semiarid regions for food, feed and biofuel production. Cold and drought stresses reduce photosynthesis in sorghum, limiting biomass production and yield. It is necessary to understand the genetic mechanisms controlling stress response to develop cultivars with increased cold and drought tolerance. We performed genome wide association studies (GWAS) for gas exchange and chlorophyll fluorescence traits in sorghum. The main objective was to discover genes/genomic regions that control the photosynthetic capacity under optimal, low temperature and drought stress conditions. Two experiments were conducted ...


Using Genomic And Gene Expression Methods To Understand The Phenotypic Response Of Soybean To Sudden Death Syndrome Caused By Fusarium Virguliforme, Alexander Stephen Luckew Jan 2018

Using Genomic And Gene Expression Methods To Understand The Phenotypic Response Of Soybean To Sudden Death Syndrome Caused By Fusarium Virguliforme, Alexander Stephen Luckew

Graduate Theses and Dissertations

Soybean sudden death syndrome (SDS) is one of the most important soybean diseases in the Midwestern United States, leading to average losses of $396 million per year from 1996 to 2015. The causal agent of SDS, soilborne fungus Fusarium virguliforme (Fv), causes root rot symptoms and releases phytotoxins taken up by the plant to produce chlorosis and necrosis in the leaves. The main management practice used to reduce the impact of SDS is planting resistant soybean cultivars. Resistance to SDS is known to be quantitative with 88 known quantitative trait loci (QTL) based on Soybase.org. Many of these QTL ...


Cover Crop Effects On Maize Productivity: Insights From Statistical And Process-Based Models, Guillermo Marcillo Jan 2018

Cover Crop Effects On Maize Productivity: Insights From Statistical And Process-Based Models, Guillermo Marcillo

Graduate Theses and Dissertations

Winter cover crops can be an effective strategy to buffer soil and water impairing effects from intensively managed agriculture. While cover crops have shown potential to sequester off-season nitrate, control weeds, or promote nutrient cycling, knowledge gaps persist in regard to maize impacts driven by cover crop decision making. In this context, statistical and process-based models can be valuable tools for predicting changes in maize systems that include a winter cover crop. In a meta-analysis combining peer-reviewed research from several regions in the US, grain yields were found to change between 0 and 21% when maize (Zea mays L.) followed ...


Phenotypic And Genomic Selection For Multi-Trait Improvement In Soybean Line And Variety Development, Andreomar Kurek Jan 2018

Phenotypic And Genomic Selection For Multi-Trait Improvement In Soybean Line And Variety Development, Andreomar Kurek

Graduate Theses and Dissertations

Marker technologies have allowed soybean breeding to exploit genotypic information for traits of various genetic architectures. However, the incorporation of technologies have had qualitative impacts on resources used in variety development projects. The objective of this study was to investigate the impact of integrating Marker Assisted Selection (MAS) for single gene and oligo-genic traits and Genomic Selection (GS) for yield in soybean variety development projects through use of simulations, decision classifier metrics, and cost analysis. The breeding goals of the project are to maximize yield of soybean varieties adapted to maturity zones (MZs) II, III and IV, while assuring that ...


Soybean [Glycine Max (L.) Merr.] Agronomic Performance, Seed Characteristics, And Aconitase Isozymes Variability In Response To Environmental Stimuli, Grace Kaudzu Jan 2017

Soybean [Glycine Max (L.) Merr.] Agronomic Performance, Seed Characteristics, And Aconitase Isozymes Variability In Response To Environmental Stimuli, Grace Kaudzu

Graduate Theses and Dissertations

Environmental stimuli can generate intra-cultivar genetic variation in nearly homozygous soybean cultivars. This genetic variation may be useful for enhancing genetic diversity and developing new cultivars. Soybean plants exposed to multiple environmental stimuli produce seed variants with different phenotypic and genotypic characteristics. When these variants are selfed, the variation is heritable and stable. Seed produced in plants subjected to wide-spaced honeycomb (HC) planting, natural hail and to a modified accelerated aging (AA) at planting has exhibited intra-cultivar genetic variation. However, the effect of a single environmental stimulus on agronomic performance, seed characteristics and stability of variants from a soybean plant ...


How Does Inclusion Of Weather Forecasting Impact In-Season Crop Model Predictions?, Kaitlin Togliatti Jan 2017

How Does Inclusion Of Weather Forecasting Impact In-Season Crop Model Predictions?, Kaitlin Togliatti

Graduate Theses and Dissertations

Accurately forecasting crop yield in advance of harvest could greatly benefit decision makers. However, few evaluations have been conducted to determine the effectiveness of including weather forecasts, as opposed to using historical/climatology data, into crop models. We tested a combination of short-term weather forecasts from the Weather Research and Forecasting Model (WRF) to predict in season weather variables, such as, maximum and minimum temperature, precipitation, and radiation at four different forecast lengths (14 days, 7 days, 3 days, and 0 days). This forecasted weather data along with the current and historic (previous 35 years) data were combined to drive ...


Production, Perceptions And Limitations Of Organic Small Grains In Iowa, David Weisberger Jan 2017

Production, Perceptions And Limitations Of Organic Small Grains In Iowa, David Weisberger

Graduate Theses and Dissertations

Small grains, such as, barley (Hordeum vulgare L.), oat (Avena sativa L.), rye (Secale cereale L.), triticale (X Triticosecale Wittmack) and wheat (Triticum aestivum L.) contribute to the proper functioning of organic row crop systems in Iowa and the upper Midwest. Besides producing grain and straw, which have value either as sold products or on-farm inputs, they are commonly used rotation crops that contribute functions such as forage legume establishment and weed suppression. Additionally, they may contribute to a suite of below ground functions that included soil quality improvement and disease suppression. However, small grains themselves are less profitable than ...


Identification Of Spectral Disease Signatures And Resistant Qtl For Charcoal Rot Infection In Soybean, Sarah Jones Jan 2017

Identification Of Spectral Disease Signatures And Resistant Qtl For Charcoal Rot Infection In Soybean, Sarah Jones

Graduate Theses and Dissertations

Disease phenotyping is an important process for both production field scouting and disease rating in soybean [Glycine max (L.) Merr.] breeding programs because yield is affected by many pathogens including charcoal rot, Macrophomina phaseolina. Charcoal rot has limited chemical control options and affects over 500 species worldwide making crop rotation a difficult management strategy as well. Due to these management challenges, breeding for disease resistance is a valuable strategy, however traditional disease phenotyping relies on human visual ratings which are prone to human error and have scalability issues when moving to large production schemes or modern breeding programs. Furthermore, there ...


Genetic Studies On Self-Fertility In Perennial Ryegrass (Lolium Perenne L.) With Implications For Hybrid Breeding In Allogamous Grasses, Javier Do Canto Fagundez Jan 2017

Genetic Studies On Self-Fertility In Perennial Ryegrass (Lolium Perenne L.) With Implications For Hybrid Breeding In Allogamous Grasses, Javier Do Canto Fagundez

Graduate Theses and Dissertations

Perennial grasses have diverse uses and are relevant from the agronomic and economic point of view, with main uses as forage, turf and bioenergy. In the grass family polyploidy is prevalent and both autopolyploids and allopolyploids are present. Also, within grasses there are a range of breeding systems, but hermaphrodite flower is the most frequent floral condition. Cross-pollination in species with hermaphrodite flowers is imposed by a gametophytic genetic self-incompatibility (SI). SI is controlled by two multiallelic and independent loci, S and Z. The incompatibility phenotype of the pollen grain is determined by its haploid genome. A pollen grain is ...


Molecular And Phenotypic Characterization Of Doubled Haploid Exotic Introgression Lines For Nitrogen Use Efficiency In Maize, Darlene Lonjas Sanchez Jan 2017

Molecular And Phenotypic Characterization Of Doubled Haploid Exotic Introgression Lines For Nitrogen Use Efficiency In Maize, Darlene Lonjas Sanchez

Graduate Theses and Dissertations

Nitrogen (N) is an important macroelement for promoting crop growth and development, and is essential for increased grain yield. However, less than half of the N fertilizer applied goes into the grain, and excess N goes back into the environment. Developing maize hybrids with improved nitrogen use efficiency (NUE) can help minimize N losses, and in turn reduce adverse ecological, economical, and health consequences. The root system plays a major role in the acquisition of N, as well as water and nutrients; thus, selecting for root architecture traits ideal for N uptake might help improve NUE in maize. This project ...


Investigations Into Nutritional Quality, Commercial Productivity, And Genetic Purity Of Maize Grain For Organic Production Systems, Ryan Huffman Jan 2017

Investigations Into Nutritional Quality, Commercial Productivity, And Genetic Purity Of Maize Grain For Organic Production Systems, Ryan Huffman

Graduate Theses and Dissertations

Consumer demand for organic maize grain has steadily increased in the past decade which has resulted in an increased interest for this market class by plant breeders and geneticist. Each chapter in this dissertation investigates areas of concern to the organic community and possible solutions for improvement. Chapter 2 seeks to understand which combinations of genetic mechanisms are capable of a further increase in the methionine concentration of maize grain over individual mechanisms. Based on the genetic mechanisms evaluated, it was concluded that crosses combining dzr1 and recurrent selection in hybrid combination can elevate methionine concentration and overall grain nutritional ...


Genome Wide Association Study Of Seed And Seedling Root Traits In Sunflower, Ze Tian Fang Jan 2017

Genome Wide Association Study Of Seed And Seedling Root Traits In Sunflower, Ze Tian Fang

Graduate Theses and Dissertations

Cultivated sunflower (Helianthus annuus L.) is an internationally important crop harvested for seed oil and confectionary purposes. Sunflower unlike many other crops, has an extensive root system that can provide drought avoidance under water limiting conditions in the field. This genome wide association (GWA) study utilized 2D images of seeds and seedling roots from a diverse panel of sunflower genotypes (n = 288 lines) for QTL detection. The subsequent analyses of these images revealed vast phenotypic variation in total root length (mean = 169 cm, SD = 81 cm) and primary root length (mean = 29 cm, SD = 7 cm). ANOVA and PCA based ...


Impact Of Climate Change On Soybean Breeding Objectives, Theodore M. I. Hartman Dec 2016

Impact Of Climate Change On Soybean Breeding Objectives, Theodore M. I. Hartman

Meteorology Senior Theses

Changes in climate, mainly changes in temperature, precipitation, and carbon dioxide concentration are predicted to occur. These changes in climate will affect weather conditions that are vitally important in the growth and development of crops. Historically, yield increases have been observed in many crops, including Glycine max (soybean). This yield increase has been associated with deliberate breeding objectives designed to optimize plant performance for the contemporary climate. This deliberate breeding initiative has modified plant physiologic parameters. This study looks at how changes in soybean physiological parameters, through different cultivars, have attributed to observed yield increases and how future climate changes ...


Biomass Sorghum And Maize Have Similar Water-Use-Efficiency Under Non-Drought Conditions In The Rain-Fed, Midwest Us, Matthew Roby Jan 2016

Biomass Sorghum And Maize Have Similar Water-Use-Efficiency Under Non-Drought Conditions In The Rain-Fed, Midwest Us, Matthew Roby

Graduate Theses and Dissertations

Biomass sorghum [Sorghum bicolor (L.) Moench.] is a candidate bioenergy feedstock in the Midwest, US. Research suggests that biomass sorghum is more drought tolerant and has higher water-use-efficiency (WUE; the ratio of cumulative biomass production to total evapotranspiration; g kg-1) than Zea mays (maize) in water-limiting environments. However, comparisons of the seasonal evapotranspiration (total ET) and WUE of biomass sorghum and maize have focused on irrigated systems and are scarce for the rain-fed, Midwest. We conducted a side-by-side comparison of the total ET and WUE of maize and biomass sorghum at a site within the US Corn Belt. Total ET ...


Cover Crop Options And Mixes For Upper Midwest Corn-Soybean Systems, Seth R. Appelgate Jan 2016

Cover Crop Options And Mixes For Upper Midwest Corn-Soybean Systems, Seth R. Appelgate

Graduate Theses and Dissertations

The implementation of cover crops in Iowa has the potential to decrease soil erosion, weed density, and nitrate leaching while increasing soil organic carbon. This study investigated nine potential cover crops; winter rye (Secale cereale L.), winter triticale (Triticale hexaploide Lart.), two winter canola (Brassica napus L.) varieties, winter camelina [Camelina sativa (L.) Crantz], spring barley (Hordeum vulgare L.), spring oat (Avena sativa L.), purple top turnip (Brassica rapa L.), and hairy vetch (Vicia villosa Roth). Cover crops were planted as sole crops and selected binary and trinary mixtures. A control treatment of no cover crop was included. Cover crops ...


Improved Production Systems For Common Bean In South-Central Uganda: I. Liddugavu Soil, Ii. Limyufumyufu Soil, Lance Henry Goettsch Jan 2016

Improved Production Systems For Common Bean In South-Central Uganda: I. Liddugavu Soil, Ii. Limyufumyufu Soil, Lance Henry Goettsch

Graduate Theses and Dissertations

Common bean (Phaseolus vulgaris L.) is the most important source of dietary protein in Uganda but current grain yields are extremely low. Beans are produced on a variety of soils in south-central Uganda but the two most important soils for bean production are the highly weathered Limyufumyufu (Ferralsol) and the relatively fertile Liddugavu (Phaeozem) soils. These two soils vary in level of pH and fertility and therefore must be managed appropriately. Beans managed under conventional systems have a yield gap of about 75% due to poor agronomic practices, soil infertility, lack of seed from improved cultivars, moisture stress, weed competition ...


Effects Of Recurrent Selection For Yield On Plant Growth Across Planting Densities In Maize (Zea Mays L.), Michael Jonathan Stein Jan 2016

Effects Of Recurrent Selection For Yield On Plant Growth Across Planting Densities In Maize (Zea Mays L.), Michael Jonathan Stein

Graduate Theses and Dissertations

Breeding for higher grain yield in maize (Zea mays L.), utilizing increased selection densities, has produced varieties that are adapted to grow at higher population densities. The effects of increased planting density on grain yield and final phenotypes are well known, but the effects of density on plant growth across the growing season have been less widely characterized. The objectives of this study were: 1) examine the effects of high planting density on growth rates, growth timing, and biomass partitioning of the ear, stalk, and tassel; 2) characterize the difference in density effects in maize populations before and after recurrent ...


A Genetic And Genomic Study Of Resistance To 4-Hydroxyphenylpyruvate Dioxygenase (Hppd) Inhibitor Herbicides In Amaranthus Tuberculatus (Waterhemp), Daniel Robert Kohlhase Jan 2016

A Genetic And Genomic Study Of Resistance To 4-Hydroxyphenylpyruvate Dioxygenase (Hppd) Inhibitor Herbicides In Amaranthus Tuberculatus (Waterhemp), Daniel Robert Kohlhase

Graduate Theses and Dissertations

Waterhemp (Amaranthus tuberculatus) is an agronomic weed found throughout the Midwestern United States. Without proper management waterhemp has the potential to cause yield losses up to 74% and 56% in maize (Zea mays L.) and soybean [Glycine max (L.) Merr.], respectively. There are various characteristics of waterhemp that contribute to increasing prevalence of waterhemp in agriculture including the ability to evolve herbicide resistance. There are six herbicide sites of action that have been evolved in waterhemp. In 2011, waterhemp was discovered to be resistant to p-hydroxyphenylpyruvate-dioxygenase (HPPD, EC 1.13.11.27) inhibitor herbicides. The objectives of my research were ...


Investigation Of The Anti-Virc2 Transcript In Agrobacterium Tumefaciens, Abbagail Lauren Johnson Jan 2016

Investigation Of The Anti-Virc2 Transcript In Agrobacterium Tumefaciens, Abbagail Lauren Johnson

Graduate Theses and Dissertations

Agrobacterium tumefaciens has long been an important tool for plant genetic transformation. Many important crop plants such as maize, soybean, wheat, and rice, as well as numerous other dicot plant species are able to be transformed using A. tumefaciens. While many potential regulatory RNA have been previously identified in A. tumefaciens, very few have been verified with a functional investigation. With the growing understanding of regulatory RNA, and its importance in gene regulation, it is essential to further classify regulatory RNA in the transformative tool A. tumefaciens. It is possible that regulatory RNA could be involved in virulence and their ...