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Autophagy- And Rns2-Mediated Mechanism Of Ribosomal Rna Degradation In Arabidopsis Thaliana, Stephanie C. Morriss Jan 2016

Autophagy- And Rns2-Mediated Mechanism Of Ribosomal Rna Degradation In Arabidopsis Thaliana, Stephanie C. Morriss

Graduate Theses and Dissertations

Ribosomal RNA degradation is necessary to remove nonfunctional rRNA and maintain homeostasis through degradation of aging or normal rRNA. While pathways for surveillance of nonfunctional rRNA have been characterized, mechanisms of degradation of normal rRNA are not yet well understood. Ribosomal RNA, the majority of cellular RNA, forms a massive resource sink. These studies examine the mechanism of degradation of rRNA in Arabidopsis and the effects of disruption of this process through mutation of key genes.

Ribosomal RNA in many organisms, including yeast, zebrafish, Tetrahymena and Arabidopsis, is degraded by the RNase T2 family of enzymes, a family highly conserved ...


Evaluating Temperate And Tropical Corn For Biomass Production In Central Iowa, Pedro Alexander Infante-Posada Jan 2016

Evaluating Temperate And Tropical Corn For Biomass Production In Central Iowa, Pedro Alexander Infante-Posada

Graduate Theses and Dissertations

Corn (Zea mays L.) grain in part has been used in Midwestern U.S. for bioethanol production; however, corn stover for lignocellulosic ethanol is gaining interest as an alternative source of energy. Over two years, three studies explored the biomass potential of tropical corn, corn adapted from tropical regions, for biomass production toward lignocellulosic ethanol. The first study investigated the phenology of adapted and non-adapted tropical corn populations grown under central Iowa conditions. Field trials were conducted where three adapted populations (Tuxpeño, Suwan, and Tuson) and their non-adapted counterparts were planted at three dates during the 2014 and ...


Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges Jan 2016

Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges

Graduate Theses and Dissertations

A male-sterile, female-sterile mutant was identified in a transposon-tagging study in soybean (Glycine max L.). This mutant displayed abnormalities in both micro- and mega-sporogenesis, as well as gametogenesis. Vegetatively, the mutant showed no visible differences from the wild-type phenotype. Analyses of male meiotic chromosomes were done to better understand any issues that could occur to cause sterility. Wild-type and mutant anthers and ovules were cleared throughout their development, followed by confocal scanning laser microscopy to look for any abnormalities, and to determine the timing of abortion in both the male and female organs in the mutant. Additionally, scanning electron microscopy ...


Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges Jan 2016

Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges

Graduate Theses and Dissertations

A male-sterile, female-sterile mutant was identified in a transposon-tagging study in soybean (Glycine max L.). This mutant displayed abnormalities in both micro- and mega-sporogenesis, as well as gametogenesis. Vegetatively, the mutant showed no visible differences from the wild-type phenotype. Analyses of male meiotic chromosomes were done to better understand any issues that could occur to cause sterility. Wild-type and mutant anthers and ovules were cleared throughout their development, followed by confocal scanning laser microscopy to look for any abnormalities, and to determine the timing of abortion in both the male and female organs in the mutant. Additionally, scanning electron microscopy ...


Quantifying Senescence-Mediated Nutrient Loss Processes In Switchgrass (Panicum Virgatum L.) Biomass, Ruth Helen Burke Jan 2016

Quantifying Senescence-Mediated Nutrient Loss Processes In Switchgrass (Panicum Virgatum L.) Biomass, Ruth Helen Burke

Graduate Theses and Dissertations

The annual senescence that occurs in many perennial grass species is not a terminal event, and multiple internal processes are occurring as a plant enters winter or dry-season dormancy. When grown as bioenergy feedstocks, end-season nutrient conservation and loss processes taking place in perennial grasses are of interest to producers attempting to maximize yield while reducing residual nutrient content in the harvestable biomass. The residual nutrient content in these bioenergy feedstocks can reduce conversion efficiency, damage biorefinery equipment, and even cause pollution. In order to better understand nutrient cycling in perennial grasses as well as improve harvest management decisions for ...


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 Germination, Growth, Sporulation, And Host-Induced Rna Interference In Fusarium Virguliforme, Jill Marshall Jan 2016

Investigation Of Germination, Growth, Sporulation, And Host-Induced Rna Interference In Fusarium Virguliforme, Jill Marshall

Graduate Theses and Dissertations

xSudden death syndrome (SDS) is one of the leading soybean diseases in the United States. The disease is caused by a soil-borne fungi Fusarium virguliforme in North America and by four Fusarium species, F. virguliforme, F. tucumaniae F. brasiliense and F. crassitipitatum, in South America. F. virguliforme infects the roots of soybean plants and releases toxins which causes the interveinal chlorosis and necrosis on leaves, premature defoliation, and flower and pod abortion that are typical foliar SDS symptoms. Yield losses associated with SDS can be economically devastating depending on disease intensity and timing of disease onset. Host-induced gene silencing (HIGS ...


Nitrogen Pools And Fluxes In Diversified Cropping Systems, William Robert Osterholz Jan 2016

Nitrogen Pools And Fluxes In Diversified Cropping Systems, William Robert Osterholz

Graduate Theses and Dissertations

Achieving high crop yields requires a large supply of plant available nitrogen (N), yet losses of inorganic N from agriculture are deleterious to environmental quality. A significant portion of agricultural N losses could be prevented if large soil inorganic N pools were not needed to satisfy crop N demand. Alternative N management strategies that consider N fluxes like gross N mineralization in addition to N pools should be investigated, as they could conceivably reduce the size of soil inorganic N pools while still providing sufficient N for crop production. Diversified cropping systems may be able to utilize such alternative N ...


Factors Affecting Expression Of Soybean Sudden Death Syndrome: Flooding, Oxygen Level, And Ethylene Hormone, Noor Abdelsamad Jan 2016

Factors Affecting Expression Of Soybean Sudden Death Syndrome: Flooding, Oxygen Level, And Ethylene Hormone, Noor Abdelsamad

Graduate Theses and Dissertations

Soybean [Glycine max (L.) Merrill] sudden death syndrome (SDS), caused by the soilborne fungus Fusarium virguiforme (Fv), is a very damaging disease in North and South America, with average yield losses in the Unites States estimated at 190 million dollars annually between 1999 and 2004. Major SDS outbreaks have coincided with years of extreme flooding, such as 1993, 2008, and 2010, but there is no information about how and why excessive soil moisture is associated with severe SDS. In this study, the first objective was to investigate the effect of different flood regimes on the development of SDS under greenhouse ...


Evaluation Of Conditions Affecting Agrobacterium-Mediated Genetic Transformation Of Soybean (Glycine Max L.) And Common Bean (Phaseolus Vulgaris L.), Amber Lynn Testroet Jan 2016

Evaluation Of Conditions Affecting Agrobacterium-Mediated Genetic Transformation Of Soybean (Glycine Max L.) And Common Bean (Phaseolus Vulgaris L.), Amber Lynn Testroet

Graduate Theses and Dissertations

With the need for increased food production by 70% by 2050, plant genetic transformation plays a key role in the development of crops more tolerant to stress, pests, and disease. Legumes are immensely important in terms of nutritional and economic value in addition to nitrogen fixation capabilities. However, legumes have often proved difficult to transform with genetic engineering. This thesis evaluates conditions affecting genetic transformation of soybean (Glycine max L.) and common bean (Phaseolus vulgaris L.).

Transformation of soybean is now routine but requires much skill and labor. To reduce the labor required for the transformation of soybean, it is ...


Assessment Of Tassel Initiation In Maize Inbred Lines Under Field Conditions Using Florigen Expression, Juan Pablo San Martin Toloza Jan 2016

Assessment Of Tassel Initiation In Maize Inbred Lines Under Field Conditions Using Florigen Expression, Juan Pablo San Martin Toloza

Graduate Theses and Dissertations

Synchronizing male and female flowers in hybrid maize (Zea mays L.) seed production is critical for maximum yields of high quality seed. Many factors may delay planting in a particular region beyond the optimal planting time, creating a different temperature and photoperiod environment interacting with a female and male maize inbred pair. Maize ontogeny is controlled by temperature and photoperiod, although publications disagree on the magnitude of impact these factors have. The transition of the shoot apical meristem (SAM) from vegetative to reproductive growth in maize it is called tassel initiation (TI). TI is always preceded by an accelerated expression ...


Organic No-Till And Strip-Till Systems For Broccoli And Pepper Production, Dana Lipinski Jokela Jan 2016

Organic No-Till And Strip-Till Systems For Broccoli And Pepper Production, Dana Lipinski Jokela

Graduate Theses and Dissertations

Organic farmers rely extensively on tillage to incorporate plant residues, prepare seedbeds, and control weeds. However, tillage may have adverse effects on soil health, and conventional no-till production methods, which rely on herbicide for weed control, are not compatible with organic farming, so research was conducted on organic no-tillage (NT) and strip-tillage (ST), which rely on terminating a cover crop with a roller-crimper. Field research was carried out over two years (2013–14 and 2014–15) to compare two organic, cover crop-based reduced tillage systems (NT and ST) with conventional tillage (CT) in the production of organic bell pepper and ...


Sedge Meadow Response To Various Experimental Treatments, Mitchell Austin Baalman Jan 2016

Sedge Meadow Response To Various Experimental Treatments, Mitchell Austin Baalman

Graduate Theses and Dissertations

Plant density, species diversity, and the biomass of sedge meadow species were measured in mesocosms treated with one of two levels of four treatments in a randomized block experiment: stratified or not stratified seed, high or low groundwater level, high or low seeding density, and a complete set of all species or a split-set where non-aggressive species were seeded in the spring and aggressive species were seeded the following fall. The study was conducted at Iowa State University’s Hinds Research Farm in Ames, IA from 2013-2016. The high groundwater level had the greatest impact on increasing the plant density ...


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 ...


Reducing Herbicide Use Through Cropping System Diversification: A Case Study At The Iowa State University Marsden Farm, And Some Recommendations For The Mekong Delta Of Vietnam, Huong Nguyen Jan 2016

Reducing Herbicide Use Through Cropping System Diversification: A Case Study At The Iowa State University Marsden Farm, And Some Recommendations For The Mekong Delta Of Vietnam, Huong Nguyen

Graduate Theses and Dissertations

Crop production in the Midwestern U.S. and Vietnam’s Mekong Delta requires sustainable and cost effective weed management strategies because both regions are grappling with increasing weed resistance to herbicides, and concerns over environmental damage from herbicides. Agroecological approaches that employ diverse cropping systems to subject weeds to multiple stress and mortality factors may provide reliable weed management that is cost efficient and less reliant on chemicals. Agroecological weed control is based on sound understanding of weed population dynamics, natural resources, and climate attributes, and thus is practical regardless of the level of technology to which farmers have access ...


Brassinosteroid And Gibberellin Control Of Plant Height In Maize (Zea Mays. L), Songlin Hu Jan 2016

Brassinosteroid And Gibberellin Control Of Plant Height In Maize (Zea Mays. L), Songlin Hu

Graduate Theses and Dissertations

Brassinosteroids (BRs) and gibberellins (GAs) are two major plant hormones involved in many plant developmental processes. However, the knowledge of BR and GA control of agronomic traits in maize is limited compared to model species Arabidopsis and rice, especially BR. This PhD project focused on BR and GA control of plant height from genetics and plant biology perspectives, as these two plant hormones have shown great impact for shaping plant height, and a short/tall stature of maize height is beneficial for grain/biomass production, respectively. We introgressed multiple exotic accessions into two maize heterotic groups Stiff Stalk and Non ...


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 ...


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 ...


Tno1 & Vps45: Snare-Associated Proteins Required For Plant Growth, Rahul Roy Jan 2016

Tno1 & Vps45: Snare-Associated Proteins Required For Plant Growth, Rahul Roy

Graduate Theses and Dissertations

Cellular trafficking of cargo vesicles at the trans-Golgi network (TGN) is required for multiple processes such as cell expansion, stress responses and hormonal transport in plants. Activity of membrane proteins known as SNAREs drives membrane fusion events. Associated proteins such as tethering factors and Sec1/Munc18 proteins aid the fidelity and efficiency of these fusion events by interacting with SNAREs. The TGN-localized SYP41/SYP61/VTI12 SNARE complex is required for vacuolar and secretory cargo trafficking.

TNO1, a putative tethering factor, associates with SYP41 and is required for TGN membrane fusion dynamics and proper SYP61 localization. My dissertation research discovered a ...


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 ...


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 ...


Studies On Cover Crops And Sudden Death Syndrome Of Soybean, Renan Kobayashi-Leonel Jan 2016

Studies On Cover Crops And Sudden Death Syndrome Of Soybean, Renan Kobayashi-Leonel

Graduate Theses and Dissertations

Soybean sudden death syndrome (SDS), caused by Fusarium virguliforme, is a major soybean disease affecting soybean production in the United States. In search for more diversified cropping systems, the adoption of cover crops in the corn-soybean rotation is being encouraged. However, there is lack of information regarding the impact that cover cropping can have on SDS. On the one hand, it is possible that the improvements in soil health caused by cover crop can create an environment that is not favorable to the disease. On the other hand, F. virguliforme is able to colonize many plant species and, if a ...


Dissecting Adaptation Through The Exploration Of Flowering Time In Maize (Zea Mays L.), Adam Edward Vanous Jan 2016

Dissecting Adaptation Through The Exploration Of Flowering Time In Maize (Zea Mays L.), Adam Edward Vanous

Graduate Theses and Dissertations

Maize germplasm used in the central-U.S. Corn Belt is comprised of a small portion of the germplasm available; however, the importance of these exotic sources of germplasm has long been known, as they possess diversity that is essential to overcome abiotic and biotic stresses. The main reason for not utilitzing exotic germplasm is the difficulty of adapting these sources of germplasm. This thesis investigates two pre-breeding methods used to adapt exotic maize germplasm and the effects of these methods on altering the main adaption trait of flowering time. A selection mapping experiment was used to investigate flowering time in ...


Molecular Characterization Of Short And Long Term Iron Stress Responses In Soybean, Leorrie Ann Atencio Jan 2016

Molecular Characterization Of Short And Long Term Iron Stress Responses In Soybean, Leorrie Ann Atencio

Graduate Theses and Dissertations

Iron Deficiency Chlorosis (IDC) is a disease caused by lack of useable iron in the soil. Symptoms include stunting and interveinal chlorosis of the leaves, eventually leading to yield loss at the end of the season. IDC is particularly important in the upper Midwestern United States because soil conditions favor its development. With the use of next generation sequencing approaches, we characterized soybeans’ short and long-term response to iron stress. Our research takes advantage of two near isogenic lines that are 98% genetically identical but differ in their iron efficiency response. Clark plants are iron efficient, while Isoclark plants are ...


Soybean Vein Necrosis Virus: Impacts Of Infection On Yield Loss And Seed Quality And Expansion Of Plant Host Range, Melissa Irizarry Jan 2016

Soybean Vein Necrosis Virus: Impacts Of Infection On Yield Loss And Seed Quality And Expansion Of Plant Host Range, Melissa Irizarry

Graduate Theses and Dissertations

Soybean vein necrosis virus (SVNV) rapidly became a widespread soybean (Glycine max) virus within a few years of its initial confirmation in 2008. The economic impact of soybean vein necrosis (SVN) disease remains unknown. Soybean is a crop of global importance with nearly 4 billion bushels of soybeans produced in the United States in 2014. This study was designed to pursue two main questions; is there any yield loss or change in seed quality associated with SVN and are there horticultural or cover crop species that could be serving as sources of SVNV inoculum?

In order to determine if there ...


High-Throughput Phenotyping Of Above And Below Ground Elements Of Plants Using Feature Detection, Extraction And Image Analysis Techniques, Nigel Lee Jan 2016

High-Throughput Phenotyping Of Above And Below Ground Elements Of Plants Using Feature Detection, Extraction And Image Analysis Techniques, Nigel Lee

Graduate Theses and Dissertations

Plant phenotyping is now being widely used to study and increase the yield of row-crop plants. Phenotyping is defined as a set of observable characteristics of an individual that results from its interaction of its genome with the environment. Therefore, the collection of physical and observable traits is the primary task of any phenotyping study. While current phenotyping methods are painstakingly slow and tedious, advances in digital imagery and computer technology have unlocked new avenues for this arduous task. High-resolution im-ages can now easily be obtained with practically any camera whereas improvements in com-puter technology mean that images taken can ...


Genetic Variation In Native Populations Of The Laurel Wilt Pathogen, Raffaelea Lauricola, In Taiwan And Japan And The Introduced Population In The Usa, Caroline Elizabeth Wuest Jan 2016

Genetic Variation In Native Populations Of The Laurel Wilt Pathogen, Raffaelea Lauricola, In Taiwan And Japan And The Introduced Population In The Usa, Caroline Elizabeth Wuest

Graduate Theses and Dissertations

Laurel wilt is a true vascular wilt disease caused by Raffaelea lauricola, which is a mycangial symbiont of Xyleborus glabratus, an ambrosia beetle. The fungus and vector are both native to Asia, but it is believed that both were introduced to the Savannah, Georgia area about 15 years ago. Laurel wilt has caused widespread mortality on redbay (Persea borbonia) and other members of the Lauraceae in the southeastern USA, and both pathogen and vector have spread as far as Texas. It is thought that there was a single introduction of R. lauricola to the USA, but there are no extensive ...


Genome-Wide Association And Epistasis Studies Of Sclerotinia Sclerotiorum Resistance In Soybean, Tara Catherine Moellers Jan 2016

Genome-Wide Association And Epistasis Studies Of Sclerotinia Sclerotiorum Resistance In Soybean, Tara Catherine Moellers

Graduate Theses and Dissertations

Sclerotinia stem rot or white mold (WM) [Sclerotinia sclerotiorum (Lib.) de Bary] is an important fungal disease affecting soybean [Glycine max (L.) Merr.] and causes yield and quality losses. WM is prevalent in cool and moist environments, particularly in the soybean growing regions of Northern United States and Canada. Although sources of complete resistance have not yet been identified, several quantitative trait loci (QTL) for partial resistance have been reported but generally using bi-parental mapping populations. Genome-wide association (GWA) studies have been used to dissect complex disease resistance traits in plants and to identify the genes controlling the expression. WM ...


Optimal Population Value Selection: A Population-Based Selection Strategy For Genomic Selection, Matthew Daniel Goiffon Jan 2016

Optimal Population Value Selection: A Population-Based Selection Strategy For Genomic Selection, Matthew Daniel Goiffon

Graduate Theses and Dissertations

In order to feed the world’s growing population, an interdisciplinary effort is needed. In this thesis, operations research tools of mathematical modeling, optimization, and simulation are used to improve an existing plant breeding method, genomic selection. To do this, a new method, called optimal population value (OPV) selection, is proposed. In this paper, OPV selection is first defined as an optimization problem that selects a breeding population using a population metric, instead of individual metrics. Then, OPV selection is thoroughly tested in a simulation study against the existing methods of genomic selection, weighted genomic selection, and optimal haploid value ...


Potassium And Sulfur Availability And Lime Potential Of Ash Co-Product Of Corn Cellulosic Ethanol Processing, Samuel Groenenboom Jan 2016

Potassium And Sulfur Availability And Lime Potential Of Ash Co-Product Of Corn Cellulosic Ethanol Processing, Samuel Groenenboom

Graduate Theses and Dissertations

Lignin-derived ash obtained as a co-product of corn residue used for ethanol production may have value as a soil amendment. Preliminary laboratory analyses indicated that the ash had potential lime value and higher concentrations of K and S compared with other nutrients. The value of the ash to supply K and S and to increase soil pH was evaluated at two Iowa sites compared with commonly applied sources of K (KCl) and S (gypsum) and pure CaCO3. At each site, three 2-year trials were initiated to assess the K, S, and lime values of the ash. Several rates of each ...