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Quantifying The Effects Of Light Quantity And Quality On Culinary Herb Physiology, Alexander Gaston Litvin-Zabal Jan 2019

Quantifying The Effects Of Light Quantity And Quality On Culinary Herb Physiology, Alexander Gaston Litvin-Zabal

Graduate Theses and Dissertations

Lighting influences plant growth and development on a quantity and quality basis, promoting the production of both primary and secondary metabolites. While the amount of light necessary for culinary herb production is species-specific, with growth curves for increasing daily light integrals (DLI), the specific spectra of incidental light absorbed plays a role in photosynthetic efficiency, biomass partitioning, and secondary metabolites related health and nutrition. The two primary objectives of this research were to 1) Quantify morphological growth of culinary herbs under increasingly higher DLI, and 2) Identify the morphological, physiological, and phytochemical responses of selected herbs to the spectral composition ...


Disease And Insect Pest Management In Organic Cucurbit Production, Hayley Nelson Jan 2019

Disease And Insect Pest Management In Organic Cucurbit Production, Hayley Nelson

Graduate Theses and Dissertations

Organic production of cucurbit crops in the Midwest is limited by several insect pests (e.g., striped cucumber beetle, spotted cucumber beetle, squash bug, squash vine borer) and the bacterial diseases they vector (e.g., cucurbit bacterial wilt and cucurbit yellow vine disease (CYVD)). Current management strategies – low tunnels and insecticides – fail to provide reliable protection, are not durable, and are harmful to beneficial insects such as pollinators. Organic producers in the Midwest need more effective pest management options to consistently produce cucurbit crops.

A 3-year field experiment aimed to develop new row cover strategies for full-season, organic control of ...


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 ...


Development Of Phenomic-Assisted Breeding Methodologies For Prescriptive Plant Breeding, Efficient Cultivar Testing, And Genomic Studies, Kyle Parmley Jan 2019

Development Of Phenomic-Assisted Breeding Methodologies For Prescriptive Plant Breeding, Efficient Cultivar Testing, And Genomic Studies, Kyle Parmley

Graduate Theses and Dissertations

Plant scientists are beginning to harness the capabilities of high dimensional ‘omic tools (e.g., genomic, phenomic) to usher in the era of digital agriculture to allow the usage of predictive analytics. While genomic tools have been developed to exploit high-density genetic markers for breeding decision making, a gap persists in the availability of phenomic-assisted breeding methodologies. Here we develop frameworks malleable to crop species and breeding objective to leverage complex high-dimension phenomic data using machine learning (ML) and optimization techniques for the development of data driven solutions designed to empower plant scientists to; develop prescriptive breeding solutions, improve the ...


Investigating The Interactions Between Cover Crops And The Soybean Cyst Nematode Through Lab, Greenhouse, And Field Studies, Chelsea Jean Harbach Jan 2019

Investigating The Interactions Between Cover Crops And The Soybean Cyst Nematode Through Lab, Greenhouse, And Field Studies, Chelsea Jean Harbach

Graduate Theses and Dissertations

Throughout the past decade, the acres on which cover crops have been planted in agricultural systems in the United States has increased. In traditional row cropping, cover crops are sown shortly before or after the harvest of corn or soybean and grown through the fall to provide ground cover for approximately one third of the year during which the soil would otherwise be bare. Cover crops have many known environmental benefits, but the effects they may have on soybean cyst nematode (SCN), Heterodera glycines, are not well established. This dissertation describes experiments conducted i) in the laboratory and greenhouse to ...


Evaluation Of Creeping Bentgrass Responses To Fertilization With The Branched-Chain Amino Acids, Isaac Mertz Jan 2019

Evaluation Of Creeping Bentgrass Responses To Fertilization With The Branched-Chain Amino Acids, Isaac Mertz

Graduate Theses and Dissertations

Compared to other amino acids, the branched-chain amino acids (BCAA) could be effective additives in foliarly applied fertilization products due to the fact that these molecules are aliphatic, non-polar, and relatively hydrophobic. The BCAA leucine (L), isoleucine (IL), and valine (V) are synthesized in plants and essential to growth for most organisms, however, plant catabolism of BCAA is not completely understood. In humans, BCAA have been reported to increase muscle protein synthesis, and that increase was related to the intake ratio of L to IL and V.

The objective of these studies was to investigate whether BCAA could serve as ...


Assessment Of Inducibility And Spontaneous Haploid Genome Doubling In Maize (Zea Mays L.), Benjamin Thomas Trampe Jan 2019

Assessment Of Inducibility And Spontaneous Haploid Genome Doubling In Maize (Zea Mays L.), Benjamin Thomas Trampe

Graduate Theses and Dissertations

Maize is a staple food, fuel, and feed crop grown around the world. Doubled haploid technology allows for the quick of development of inbred lines for hybrid development. The maternal in vivo doubled haploid system has gained rapid adoption by the maize breeding sector within the last 10 years. There have been significant improvements in the doubled haploid technology, which made it commercially viable. Within the doubled haploid system, there is limited genetic information about the two important traits that control the ability of generating doubled haploids, which are inducibility and spontaneous haploid genome doubling. Better understanding of these two ...


Applying Computer Vision For Detection Of Diseases In Plants, Xuan Truong Tran Jan 2019

Applying Computer Vision For Detection Of Diseases In Plants, Xuan Truong Tran

Graduate Theses and Dissertations

Early detection and quantification of diseases in food plants are critical to agriculture industry and national food security. However, limitation in technology and cost has limited the success of applying Computer Vision in Plant Science. This research builds on the recent advance of Machine Learning, GPU and smartphones to tackle the problem of fast and low cost diagnosis of plant disease. In particular, we choose soybean as the subject for applying automatic disease detection. The reason is because soybean is an important crop for the state of Iowa and an important source of food for America. The plant is however ...


Deep Learning For Field-Based Automated High-Throughput Plant Phenotyping, Zhisheng Zhang Jan 2019

Deep Learning For Field-Based Automated High-Throughput Plant Phenotyping, Zhisheng Zhang

Graduate Theses and Dissertations

The current rapid development trend in Artificial Intelligence (AI) provides a vast selection of high-quality tools to solve complex problems in more efficient ways than before. As a consequence, many fields of science and engineering are starting to explore AI tools, especially Deep Learning (DL) models for visual perception, audio understanding and decision making.

This thesis explores the application of DL in plant science and agriculture to overcome the throughput bottleneck inherent in the currently practiced manual phenotyping in fields. Among many field-based phenotyping challenges, we focus on the problems of pod-counting and flower detection in soybean crop production. To ...


Age And Nitrogen Effects On Miscanthus × Giganteus Growth And Development, Mauricio D. Tejera Jan 2019

Age And Nitrogen Effects On Miscanthus × Giganteus Growth And Development, Mauricio D. Tejera

Graduate Theses and Dissertations

Perennial grasses have received increased attention in the last few decades for their potential to mitigate global energy and climate change challenges, however, basic aspects of their physiology and aging remain poorly understood. In addition, research on perennial grasses is underpinned by conventional field experiments whose designs still neglect important aspects of plant-age dynamics in these long-lived species. We used a REpeated PLAnting Year (REPLAY), also known as staggered-start, experimental design to study Miscanthus × giganteus nitrogen (N) needs and age-related changes in physiology and phenology. We conducted a REPLAY experiment with three planting years and five N rates during the ...


Modeling Yield Loss Due To Soybean Sudden Death Syndrome At Different Spatial Scales, Muhammad Mohsin Raza Jan 2019

Modeling Yield Loss Due To Soybean Sudden Death Syndrome At Different Spatial Scales, Muhammad Mohsin Raza

Graduate Theses and Dissertations

Sudden death syndrome (SDS), caused by Fusarium virguliforme (Fv), is one of the major yield-limiting diseases of soybean in the Midwest. In the U.S., annual yield losses due to SDS have ranged between 0.6 to 1.9 million metric tons during the years from 2006 to 2014, and monetary losses of up to 6.75 billion dollars have been attributed to SDS for the period of 1996 to 2016. Our understanding of the relationships between varying disease levels, pathogen density, and yield is still limited. The first objective in this study was to quantify the relationship between SDS ...


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 ...


Characterizing Climate Change In The Midwest: Magnitude Of Warming And Plausibility Of Adaptation Strategies For Maize-Based Systems, Lori Jean Abendroth Jan 2019

Characterizing Climate Change In The Midwest: Magnitude Of Warming And Plausibility Of Adaptation Strategies For Maize-Based Systems, Lori Jean Abendroth

Graduate Theses and Dissertations

Maize-based agricultural systems dominate the U.S. Midwest landscape and maintaining productive systems in the short- and long-term are high priorities for the agricultural sector. Climate change has and will continue to alter the environment in which farmers produce their crops. Information and recommendations are necessary for understanding the magnitude of warming and adaptation strategies that can mitigate intensified precipitation events, moisture shortages, and increased temperatures. The multi-faceted changes in temperature were aggregated using thermal time as an agro-climate index to describe the warming relevant for producing maize. Across 1054 counties, the change in thermal time since 1950 was disproportionally ...


Limestone Application On A Ferralsol Soil And Genotype By Environment Effects On Yield And Grain Nutrient Composition In Common Bean, Rosemary Bulyaba Jan 2019

Limestone Application On A Ferralsol Soil And Genotype By Environment Effects On Yield And Grain Nutrient Composition In Common Bean, Rosemary Bulyaba

Graduate Theses and Dissertations

Food and nutritional insecurity are prevalent in sub-Saharan Africa, where years of poor soil management have left most agricultural lands mineral deficient and low in organic matter. In Uganda, soil acidity is a major contributor to low agricultural productivity, hunger, malnutrition and the vicious cycle of poverty. To meet yield demands and nutritional needs in Uganda, publicly funded breeding programs released biofortified common bean varieties such as NAROBEAN 1 and 3, that are high yielding, drought resilient and high in commonly deficient nutrients such as iron and zinc. The main objective of this study was to determine the effect of ...


Evaluation Techniques For Sense And Spray Weed Management, Joshua J.R. Degroot Jan 2019

Evaluation Techniques For Sense And Spray Weed Management, Joshua J.R. Degroot

Graduate Theses and Dissertations

Sense and spray weed management, as defined by this paper, is the ability to detect individual or small groups of weeds within a field and selectively spray just the weeds that were detected. These technologies reduce the total volume of herbicides per unit area that would have been applied with a conventional broadcast application. Sense and spray weed management may be thought as a subcategory of traditional site-specific weed management. Sense and spray weed management technologies aim to reduce the impact of herbicides on the environment, while improving the farm’s profitability. As sense and spray weed management technologies become ...


Optimizing High Tunnel Vegetable Crop Production Through Grafting, Cultivar Selection, And Microclimate Modification, Kristine Lang Jan 2019

Optimizing High Tunnel Vegetable Crop Production Through Grafting, Cultivar Selection, And Microclimate Modification, Kristine Lang

Graduate Theses and Dissertations

Tomatoes and peppers are two of the most popular vegetable crops within the state of Iowa. Both solanaceous crops benefit from high tunnel production which allows for earlier planting and fruit production, improved yields and fruit quality, and an extended growing season. While tomatoes and peppers are two of the most economically beneficial crops to grow within high tunnels, growers struggle to optimize yields and manage the environment inside high tunnels, primarily heat and light. In the case of tomato, the use of vigorous, disease-resistant tomato rootstocks has become a sought-after production tool for increasing yields and productivity, although results ...


The Impact Of Fungicide Application Method On Soybean Canopy Coverage, Disease, Yield, Seed Quality, And Seed Fill Duration., Joshua Viggers Jan 2019

The Impact Of Fungicide Application Method On Soybean Canopy Coverage, Disease, Yield, Seed Quality, And Seed Fill Duration., Joshua Viggers

Graduate Theses and Dissertations

As input costs continue to rise and profits fluctuate, soybean farmers have maintained interest in new fungicide applications methods. Customarily, fungicides are applied directly over the top of the soybean canopy as are herbicides and insecticides. However, fungicide application methods that could improve fungicide coverage within the canopy, such as undercover applications, has gained considerable interest. Undercover applications spray fungicides between the soybean rows, using multidirectional nozzles, and over the canopy with nozzles placed above the canopy. During 2017 and 2018, field experiments located in Iowa were used to investigate the effect of fungicide application methods on coverage, disease severity ...


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 ...


Studies On The Impact Of Cover Crops On Soybean Productivity And Root Diseases, Grazieli Da Araldi Da Silva Jan 2019

Studies On The Impact Of Cover Crops On Soybean Productivity And Root Diseases, Grazieli Da Araldi Da Silva

Graduate Theses and Dissertations

Soybean (Glycine max L.) and corn (Zea mays L.) are the two main field crops grown in the Midwest, and they are usually used in a rotation system (FAOSTAT, 2018). This cropping system contributes to the elevated nitrate levels found in the surface waters in the Midwest (David et al., 1997; Dinnes et al., 2002), along with higher risk of soil erosion (Pimentel et al., 1995) and loss of nutrients and organic matter (Burkart and James, 1999; David and Gentry, 2000). Cover crops, grown between soybean or corn harvest in the fall and planting of the subsequent crop in the ...


An Analysis Of The Ramosa1 Pathway In Zea Mays Utilizing Crispr/Cas9 Knockouts, Ryan James Arndorfer Jan 2019

An Analysis Of The Ramosa1 Pathway In Zea Mays Utilizing Crispr/Cas9 Knockouts, Ryan James Arndorfer

Graduate Theses and Dissertations

Inflorescence architecture in Zea mays is affected by a large collection of interrelated genes. The ramosa genes are some of the most prominent and well-studied of these genes due to their overtly branched ear and tassel mutant phenotype. ramosa1 confers determinate, short-branch identity on branch meristems during their initiation. Several new genes are proposed to work directly with ramosa1. ail6 was identified from a Quantitative Trait Locus study to identify genes which enhance or suppress the ramosa1 branching phenotype. A Yeast-2-Hybrid study identified several genes as potential interactors with ramosa1. A CRISPR/Cas9 knockout study was performed to produce novel ...


Interactions Between Aspergillus Flavus And Stored-Grain Insects In Conventional And Transgenic Maize, Julie Aiza L. Mandap Jan 2019

Interactions Between Aspergillus Flavus And Stored-Grain Insects In Conventional And Transgenic Maize, Julie Aiza L. Mandap

Graduate Theses and Dissertations

Fungal colonization and mycotoxin contamination are chronic problems that can compromise grain quality and safety in stored maize. Aflatoxins, associated with Aspergillus flavus Link infection, are the most economically important mycotoxins. Insect damage is a major factor that predisposes grain to infection by mycotoxigenic fungi. Indianmeal moth (Plodia interpunctella Hübner) and maize weevil (Sitophilus zeamais Motschulsky) are lepidopteran and coleopteran stored-grain insects, respectively, that can cause considerable damage in stored maize. The effect of Indianmeal moth or maize weevil infestations on A. flavus colonization and vice versa in non-Bt and Bt maize hybrids with lepidopteran and coleopteran events were evaluated ...


Characterization And Application Of Arkansas Male Sterile Lines For Hybrid Rice Production, Dustin North Jan 2019

Characterization And Application Of Arkansas Male Sterile Lines For Hybrid Rice Production, Dustin North

Graduate Theses and Dissertations

Hybrid rice production using the two-line system requires developing environment genetic male-sterile (EGMS) lines which become male sterile in certain environmental conditions. EGMS lines contain genes that can be induced to express male sterility by temperature (TGMS), day length (PGMS), or both (PTGMS). Eight EGMS were tested including four lines designated as 236s, 801s, 805s, and 811s developed by the University of Arkansas System Division of Agriculture's Rice Research and Extension Center (RREC) near Stuttgart, Ark.; and four mutant male-sterile lines designated as GSOR 1, GSOR 2, GSOR 3, and GSOR 4 developed by the Dale Bumpers National Rice ...


Comparison Of Shockwave Aerification And Conventional Aerification Methods On Athletic Fields, Timothy O. Dalsgaard Jan 2019

Comparison Of Shockwave Aerification And Conventional Aerification Methods On Athletic Fields, Timothy O. Dalsgaard

Graduate Theses and Dissertations

Providing a safe and attractive playing surface should be the goal of every athletic field manager. Athletic field use is growing faster than budgets that maintain them. With the added use, there is extra demand on the playing surface, including wear and soil compaction. Developing turfgrass management that better maximizes the playing surface quality and safety is necessary. Soil compaction from repeated foot traffic can limit recovery and increase surface hardness. Many of the methods to eliminate surface hardness are limited to the off-season due to the amount of surface disruption. The Shockwave linear decompaction device offers a tool that ...


Bark Of Dirca L.: Tensile Properties, Anatomy, And Utility For Handmade Asian-Style Bark Paper, Zachary Hudson Jan 2019

Bark Of Dirca L.: Tensile Properties, Anatomy, And Utility For Handmade Asian-Style Bark Paper, Zachary Hudson

Graduate Theses and Dissertations

Dirca (Thymelaeaceae) is a genus comprising four species known as leatherwoods. All are characterized by strong fibrous bark that resists tearing perpendicular to its axis. Several Native American peoples are known to have used the bark of Dirca palustris for cordage, but the physical properties and anatomy of all four species has not been reported. I address these voids in the literature. Techniques were developed to determine the ultimate tensile strength and the modulus of elasticity of bark of all species of Dirca and of additional species from the Thymelaeaceae and other plant families. Ultimate tensile strength of Dirca spp ...


Genetic Dissection And Prediction Of Leaf Angle Across The Maize Canopy, Matthew James Dzievit Jan 2019

Genetic Dissection And Prediction Of Leaf Angle Across The Maize Canopy, Matthew James Dzievit

Graduate Theses and Dissertations

Maize’s (Zea mays L.) leaf angle has changed over the last 60 years because of intense selection pressure for high yielding hybrids under increasing planting densities. Leaf angle plays a crucial role in distributing sunlight to different canopy leaves and its optimization across the canopy is essential for increasing productivity per unit of land. This dissertation seeks to explain and predict leaf angle variation across multiple canopy levels in maize through genetic mapping, meta-analysis, and genomic prediction.

Two genetic mapping populations were developed using inbred lines B73, PHW30, and Mo17 that represent important maize heterotic groups. The two populations ...


Phenotypic And Molecular Characterization Root System Architecture In Diverse Soybean (Glycine Max L. Merr.) Accessions, Kevin G. Falk Jan 2019

Phenotypic And Molecular Characterization Root System Architecture In Diverse Soybean (Glycine Max L. Merr.) Accessions, Kevin G. Falk

Graduate Theses and Dissertations

Root system architecture (RSA), or the spatial arrangement of the root and its morphology, functions to anchor the plant, provide water and nutrient acquisition, nutrient storage and to facilitate plant-microbe interactions such as nodulation in legumes such as soybean [Glycine max L. Merr.)]. Root structure also correlates to environmental advantages, such as nutrient acquisition, drought, flood tolerance, and lodging resistance. After centuries of indirect selection for RSA, there is a focus to harness soybean RSA diversity for exploitation and implementation into cultivar development programs. Researchers have generally taken one of three strategies to approach root phenotyping including controlled laboratory, moderately ...


Integrated ‘Omics’ Characterization Of Conserved Nectar Production Mechanisms Using Floral And Extrafloral Eudicot Nectaries, Elizabeth Claire Chatt Jan 2019

Integrated ‘Omics’ Characterization Of Conserved Nectar Production Mechanisms Using Floral And Extrafloral Eudicot Nectaries, Elizabeth Claire Chatt

Graduate Theses and Dissertations

Floral and extrafloral nectar, produced by nectaries, is offered as a reward to foster plant-animal mutualisms with pollinators and invertebrate predators. Attraction of pollinators through floral nectar improves fruit set in 87 out of 115 global food crops. Meanwhile extrafloral nectar, reported in 745 genera, attracts invertebrate predators, such as ants, as an indirect defense mechanism to reduce herbivory. Nectar quality (i.e. volume and composition) strongly correlates with the efficiency of these plant-animal mutualistic interactions, yet nectar composition has typically only been defined by targeted analyses of the two most predominant classes of metabolites, carbohydrates and amino acids. Other ...


Planting Date, Cultivar Maturity, And Environment Effects On Soybean Yield And Crop Stage, Ashlyn Kessler Jan 2019

Planting Date, Cultivar Maturity, And Environment Effects On Soybean Yield And Crop Stage, Ashlyn Kessler

Graduate Theses and Dissertations

Selecting soybean (Glycine max (L.) Merr.) planting date and maturity group are important agronomic decisions that are often affected by unfavorable weather. The objective of this study was to quantify how the selection of maturity groups and later than optimal planting dates effected soybean seed yield and crop development over time across Iowa, US. Field experiments were conducted at seven locations between 2014 and 2016 for a total of 21 environments. Cultivar maturities varied by location (ranging from 2.2 to 2.5 MG) and planting dates were scheduled for 20-day intervals from early May to early July. Studied planting ...


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 ...


Current Status And Prospects Of Tomato Seed Production And Distribution In Uganda, Sharon Mbabazi Tusiime Jan 2019

Current Status And Prospects Of Tomato Seed Production And Distribution In Uganda, Sharon Mbabazi Tusiime

Graduate Theses and Dissertations

Tomato is an important vegetable and contributes to food security, income and improved livelihoods to small-landholder farmers across Uganda and in the Kamuli District. Studies to establish the current status and prospects of producing, processing, distributing, and maintaining quality tomato seed in Uganda are needed to assist small-landholder farmers increase tomato yield. Research presented in this dissertation utilized value chain analysis, controlled laboratory experiments, surveys, and face-to-face interviews to complete specific objectives.

The first study mapped out the tomato seed value chain for Uganda, identified key participants, their roles, and indicated presence, partial or absence of linkages between value chain ...