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Developmental Morphology, Biomass Yield And Compositional Differences Among Upland And Lowland Switchgrass (Panicum Virgatum L.) Ecotypes Grown As A Bioenergy Feedstock Crop, Muhammad Aurangzaib Jan 2015

Developmental Morphology, Biomass Yield And Compositional Differences Among Upland And Lowland Switchgrass (Panicum Virgatum L.) Ecotypes Grown As A Bioenergy Feedstock Crop, Muhammad Aurangzaib

Graduate Theses and Dissertations

Sustainable and successful development of the bioenergy industry strongly depends upon the amount and quality of bioenergy feedstock produced. Switchgrass (Panicum virgatum L.) has been identified as a model lignocellulosic bioenergy crop in the U.S. Information regarding its growth and development is considered critical for making management decisions, production of high quality feedstock and to support simulation model calibration and subsequent analysis.

In the first study (Chapter 2), we evaluated upland (‘Cave-in-Rock’, ‘Trailblazer’ and ‘Blackwell’) and lowland (‘Kanlow’ and ‘Alamo’) ecotypes of switchgrass for harvest management, morphological (phenology and leaf area index) and biomass yield differences. A field study ...


Raffaelea Spp. From Five Ambrosia Beetles In The Genera Xyleborinus And Cyclorhipidion (Coleoptera: Curcurlionidae: Scolytinae: Xyleborini), Yeganeh Gharabigloozare Jan 2015

Raffaelea Spp. From Five Ambrosia Beetles In The Genera Xyleborinus And Cyclorhipidion (Coleoptera: Curcurlionidae: Scolytinae: Xyleborini), Yeganeh Gharabigloozare

Graduate Theses and Dissertations

Five undescribed species of Raffaelea (Ophiostomatales), as well as Raffaelea sulphurea, were isolated and illustrated from the ambrosia beetle tribe Xyleborini: Raffaelea sulphurea and Raffaelea sp. A from Xyleborinus saxeseni; Raffaelea sp. B and Raffaelea sp. C from Xyleborinus attenuatus; Raffaelea sp. D from Xyleborinus gracilis; Raffaelea sp. F from Cyclorhipidion bodoanum; and Raffaelea sp. G from C. pelliculosum.

Each fungal symbiont was isolated from a single beetle host species or its galleries and characterized by culture morphology and DNA sequencing. Analysis of of 18S rDNA and translocation elongation factor sequences of five undescribed symbionts (Raffaelea sulphurea, Raffaelea sp. B ...


A Clade-Specific Arabidopsis Gene Connects Primary Metabolism And Senescence, Dallas Christopher Jones Jan 2015

A Clade-Specific Arabidopsis Gene Connects Primary Metabolism And Senescence, Dallas Christopher Jones

Graduate Theses and Dissertations

Plants have to deal with environmental insults as they cannot move to escape from stressful conditions. To do so, they have evolved novel components that respond to the changing environment. The Qua Quine Starch (QQS) gene is an Arabidopsis-specific orphan gene that connects primary metabolism and adaptation to environment changes. AT1G64360, which we term an SAQR (Senescence-associated and QQS-related) gene, respond to oxidative stress. Here, we show that SAQR is up-regulated in high-starch QQS-RNAi mutants. Bioinformatics analyses indicates that SAQR is unique to six species within the family Brassicaceae; the gene may have arisen about 20 million years ago (MYA ...


Integration Of Summer And Fall Cover Crops In Vegetable Cropping Systems, Raymond Albert Kruse Jan 2015

Integration Of Summer And Fall Cover Crops In Vegetable Cropping Systems, Raymond Albert Kruse

Graduate Theses and Dissertations

The demand for locally produced vegetables is growing in the Midwest, including Iowa. However, since vegetables are a small fraction of total cropland in the state, little research exists on approaches and techniques to increase the sustainability of vegetable production systems. Including cover crops in vegetable crop rotations can contribute to sustainability in vegetable cropping systems. This research investigated the integration of summer and fall cover crops in vegetable cropping systems to reduce weeds and nutrient leaching, improve soil chemical and biological properties, and enhance crop growth, yield, and produce quality. Cover crops studied in this research included buckwheat (Fagopyrum ...


Limited Irradiance, Artificial Fluorescent Irradiance, And Nitrate-N:Ammonium-N Impact On Biomass And Essential Oil Production Of Ocimum Basilicum L., Tara Marie Springer Jan 2015

Limited Irradiance, Artificial Fluorescent Irradiance, And Nitrate-N:Ammonium-N Impact On Biomass And Essential Oil Production Of Ocimum Basilicum L., Tara Marie Springer

Graduate Theses and Dissertations

In the United States, there is an increasing trend in consumer participation in herb gardening. One of the more popular herbs available, basil (Ocimum basilicum L.) is a culinary herb with a wide variety of uses and cultivars. With an increased need to support the growing demand for herbs, it is important to understand how various growing practices impact basil production. In particular, this research investigates several aspects of growing basil, including how limited irradiance, artificial fluorescent irradiance, and nitrate-N:ammonium-N fertilizer influences growth and essential oil production.

In our limited irradiance study, ‘Genovese’ basil plants were grown in a ...


Horticultural Evaluation Of Soy-Based Bioplastics For Container-Crop Production, Kenneth Gene Mccabe Jan 2015

Horticultural Evaluation Of Soy-Based Bioplastics For Container-Crop Production, Kenneth Gene Mccabe

Graduate Theses and Dissertations

Petroleum-based plastics and synthetic fertilizers are commonplace in container-crop production, and their use raises concerns about the sustainability of plants produced in containers. Bioplastic materials have been developed as replacements that are more sustainable, but their use has been limited to date. Using materials made from composites of soy-based [Glycine max (L.) Merr.] ingredients and commercially-available bioplastics, we fabricated containers and pelletized fertilizers to understand nutrient-release characteristics of soy-based bioplastic composites while producing plants in container-crop production. My first objective was to evaluate the growth and mineral nutritional status of a common greenhouse species [marigold (Tagetes patula L.)] grown in ...


The Role Of Plant-Derived Quaternary Ammonium Compounds, Including Carnitine And Choline-O-Sulfate, On The Biology Of The Plant Pathogen Pseudomonas Syringae And Its Interactions With The Host Species Phaseolus Vulgaris, Michael David Millican Jan 2015

The Role Of Plant-Derived Quaternary Ammonium Compounds, Including Carnitine And Choline-O-Sulfate, On The Biology Of The Plant Pathogen Pseudomonas Syringae And Its Interactions With The Host Species Phaseolus Vulgaris, Michael David Millican

Graduate Theses and Dissertations

Knowledge of the chemicals available during plant-microbe interactions is useful for promoting the growth of beneficial bacteria and predicting pathogen populations and thus the probability of disease. Pseudomonas syringae B728a is able to utilize plant-derived quaternary ammonium compounds (QACs), such as L-carnitine, choline, and choline derivatives, as osmoprotectants and nutrient sources. We explored the biological roles of carnitine and choline-O-sulfate in P. syringae. Although genes involved in carnitine catabolism were identified in other organisms, the roles of these genes have not been fully elucidated. We analyzed conflicting reports of the carnitine degradation pathway and provided evidence for a modified pathway ...


Climate-Smart Agriculture In Midwest Cropping Systems: Evaluating The Benefits And Tradeoffs Of Cover Crops, Andrea Diane Basche Jan 2015

Climate-Smart Agriculture In Midwest Cropping Systems: Evaluating The Benefits And Tradeoffs Of Cover Crops, Andrea Diane Basche

Graduate Theses and Dissertations

Climate-smart agriculture is a framework to develop and implement agricultural systems that facilitate reduced greenhouse gas emissions and increase resilience and productivity in the context of a changing climate. Winter cover crops are known to decrease soil erosion, increase soil carbon, improve water retention and have been hypothesized to reduce nitrous oxide emissions. Therefore they offer the potential to buffer projected climate change impacts for Midwestern agriculture, including increased rainfall variability. The overall objective of this dissertation research was to evaluate the mitigation and adaptation potential of cover crops in determining their efficacy as a climate-smart agricultural practice. In a ...


Improvements To The Maize (Zea Mays L.) In Vivo Maternal Doubled Haploid System, Gerald Neil De La Fuente Jan 2015

Improvements To The Maize (Zea Mays L.) In Vivo Maternal Doubled Haploid System, Gerald Neil De La Fuente

Graduate Theses and Dissertations

The maize (Zea mays L.) in vivo maternal doubled haploid system has been widely applied to maize breeding and genetics in recent decades and is an important part of the majority of public and private maize breeding programs today. The principal advantage of the doubled haploid system is the ability to generate completely homozygous inbred lines in as little as two seasons. Other advantages to this system include more rapid integration of loci of interest and increased usefulness over traditional lines developed through self-pollination. In this dissertation, some of the major problems in the maternal doubled haploid system are addressed ...


Validation And Application Of Close-Range Photogrammetry To Quantify Ephemeral Gully Erosion, Karl Richard Gesch Jan 2015

Validation And Application Of Close-Range Photogrammetry To Quantify Ephemeral Gully Erosion, Karl Richard Gesch

Graduate Theses and Dissertations

Agricultural soil erosion is a serious problem on farms because it contributes to crop yield declines and beyond farms because it is a source of sediment and chemical pollutants. Ephemeral gullies effectively convey runoff and connect agricultural uplands to off-site waters, so control of this phenomenon would benefit multiple societal sectors. Soil conservationists often employ predictive soil erosion models to develop conservation plans, but commonly used models cannot account for ephemeral gully erosion. Future models with the capability to simulate such concentrated flow erosion must be verified with field measurements. This work sought to quantify the measurement uncertainty of a ...


Bacterial Wilt Of Cucurbits: Impact Of Plant Age On Symptom Progression And Pathogen Movement And Locating Genes Associated With Host Preference And Pathogenesis In E. Tracheiphila, Qian Liu Jan 2015

Bacterial Wilt Of Cucurbits: Impact Of Plant Age On Symptom Progression And Pathogen Movement And Locating Genes Associated With Host Preference And Pathogenesis In E. Tracheiphila, Qian Liu

Graduate Theses and Dissertations

Bacterial wilt of cucurbits is a devastating disease of cucurbit crops in the mid-Atlantic region of the USA. Caused by Erwinia tracheiphila, it is transmitted by striped (Acalymma vittatum (F.)) and spotted (Diabrotica undecimpunctata howardi (Barber)) cucumber beetles. The management of bacterial wilt relies primarily on the control of cucumber beetles with insecticides. However, alternative management strategies are needed due to the high cost of insecticides and their negative impact on the environment. Understanding bacterial wilt etiology and the ecology of E. tracheiphila may provide insights to help control bacterial wilt of cucurbits.

The first objective of my thesis research ...


Strip Tillage And Rowcovers As A Potential Alternative To Black Plastic Mulch In Cucurbit Production, Jennifer Louise Tillman Jan 2015

Strip Tillage And Rowcovers As A Potential Alternative To Black Plastic Mulch In Cucurbit Production, Jennifer Louise Tillman

Graduate Theses and Dissertations

The use of tillage and plastic mulch are common practices among cucurbit growers to provide warm, moist, weed-free soil around plants. However, there are environmental drawbacks to the use of plastic mulches, such as the material waste given that these products are used for a single season, and the reduced soil health and stability that can come from frequent and intensive tillage. As an alternative strategy, a biological mulch can be formed by rolling and killing a cover crop stand by using a roller crimper. Narrow, tilled strips can be formed within this mulch for the crop to grow in ...


Screening Of Herbicides For Selective Weed Control In African Marigold (Tagetes Erecta), Katie Jean Demers Jan 2015

Screening Of Herbicides For Selective Weed Control In African Marigold (Tagetes Erecta), Katie Jean Demers

Graduate Theses and Dissertations

African marigold (Tagetes erecta L.) was screened for tolerance to preemergence and postemergence herbicides. Three preemergence herbicides, pendimethalin, bensulide, and trifluralin, had an acceptable margin of crop safety both in the greenhouse and in the field when applied at one, two, and four times their labeled rates. Two postemergence herbicides, topramezone and encapsulated acetochlor, caused minimal visual injury to the crop and encapsulated acetochlor had a minimal effect on plant dry weight. Dry weight response to topramezone varied among experiments. Additional studies were conducted to better define African marigold tolerance to topramezone. African marigolds tolerated rates up to 36.8 ...


Influence Of Bradyrhizobium Inoculation And Fungicide Treatment On Development And Yield Of Selected Pulse Crops; Nutritional Composition Of Pulse Legume Leaves And The Impact Of Leaf Removal On Yield, Rosemary Bulyaba Jan 2015

Influence Of Bradyrhizobium Inoculation And Fungicide Treatment On Development And Yield Of Selected Pulse Crops; Nutritional Composition Of Pulse Legume Leaves And The Impact Of Leaf Removal On Yield, Rosemary Bulyaba

Graduate Theses and Dissertations

Part 1

Declining soil fertility due to inadequate nitrogen in most soils limits farmers’ goals of increasing yield. There is environmental and agricultural benefit of reducing dependence on nitrogen fertilizer by emphasizing adaptation of favorable farming practices that minimize nitrogen fertilizer. Cowpea [Vigna unguiculata (L.) Walp.] and lablab (Lablab purpureus (L.)] are pulses with potential for grain, forage, and cover crops in the Midwest of United States, but little is known about their growth, development, and productivity potential in Iowa. We conducted a two-year field study to determine the influence of rhizobia inoculation and fungicide seed treatment of selected pulses ...


Analysis Of The Role Of Rns2 And Autophagy In The Turnover Of Ribosomal Rna In Arabidopsis Thaliana, Brice Edward Floyd Jan 2015

Analysis Of The Role Of Rns2 And Autophagy In The Turnover Of Ribosomal Rna In Arabidopsis Thaliana, Brice Edward Floyd

Graduate Theses and Dissertations

The degradation and turnover of cellular components is essential for biological systems to remove damaged components and maintain functional intracellular contents. Autophagy is a vesicle-mediated process by which cellular contents can be degraded through trafficking to the lysosome or vacuole where lytic processes occur. The majority of a cell’s RNA and large quantities of its protein can be found in ribosomes. Ribosomes represent a significant metabolic investment. However, little is known about the turnover of these highly abundant ribonuclear organelles in plants.

RNase T2 enzymes represent a widely conserved class of ribonucleases present in the genomes of nearly all ...


Identification Of Qtl Associated With Nitrogen Metabolism In A Maize (Zea Mays L. Ssp. Mays) Testcross Population, Ignacio Trucillo Silva Jan 2015

Identification Of Qtl Associated With Nitrogen Metabolism In A Maize (Zea Mays L. Ssp. Mays) Testcross Population, Ignacio Trucillo Silva

Graduate Theses and Dissertations

Maize is a widely cultivated crop in the world and its production relies heavily on nitrogen (N) fertilization. N is an essential mineral nutrient for plant growth and development. However, during the last decades excessive quantities of N have been applied by farmers, a surplus to what maize plants can uptake, and several problems have arisen, such as pollution of the ecosystem and an economic loss to farmers. Breeding maize hybrids that are more efficient in the use of N is a long term goal for plant breeders. Nonetheless, previous to breeding, the genetic basis of N-metabolism in maize would ...


Local Vs. Systemic Modifications Of Soybean (Glycine Max) Defense Signals In Response To Soybean Aphid (Aphis Glycines Matsumura) Infestation, Khoi Nguyen Jan 2015

Local Vs. Systemic Modifications Of Soybean (Glycine Max) Defense Signals In Response To Soybean Aphid (Aphis Glycines Matsumura) Infestation, Khoi Nguyen

Graduate Theses and Dissertations

Soybean aphids, Aphis glycines, are a specialized phloem-feeding pest of soybeans. They are known to employ different mechanisms to bypass plant defenses and reduce soybean plant yields of up to 50% a year. Once attacked or sensing distress, soybeans induce the oxylipin pathway, a biosynthetic pathway that produces key plant hormones. Among these hormones is jasmonic acid (JA), which is produced from linolenic acid (18:3). Jasmonic acid can signal the production of protease inhibitors as one of the products that obstructs the attackers’ ability to digest protein. Previous studies show that levels of three key fatty acid precursors (palmitic ...


Phenotypic Plasticity And Heterosis: Insights From Sorghum Flowering Time And Plant Height, Xin Li Jan 2015

Phenotypic Plasticity And Heterosis: Insights From Sorghum Flowering Time And Plant Height, Xin Li

Graduate Theses and Dissertations

Investigating the genetic basis of complex traits is critical for crop improvement. The focus of my project is to study genotype by environment interaction (G × E) of flowering time and heterosis of plant height in sorghum. These two traits, flowering time and plant height, were measured on a recombinant inbred line (RIL) population in 7 environments (Guayanilla Puerto Rico and Manhattan Kansas in 2011 and 2012, Ames IA in 2013 and 2014, and Santa Isabel Puerto Rico in summer 2014). As a follow up of the flowering time QTL mapping study, we used RNA-sequencing (RNA-seq) to study gene ...


Plant Molecular Farming For The Production Of Industrial Enzyme And Vaccines, Hartinio N. Nahampun Jan 2015

Plant Molecular Farming For The Production Of Industrial Enzyme And Vaccines, Hartinio N. Nahampun

Graduate Theses and Dissertations

Since the realization of plant genetic modification, transgenic plants have been utilized as platform for the production of valuable recombinant proteins or also known as plant molecular farming (PMF). The plant offers an economical system to reduce cost, the possibility of large scale production and is free of pathogens. The plant also provides versatility o products to accumulate from industrial enzymes, peptides, and pharmaceuticals. Recent advancement of RNA as regulator of gene expression and antiviral responses has shown a new area of research where transgenic plants are used to accumulate therapeutic RNAs. In this study, the reliability of transgenic plants ...


Changes In Extreme Precipitation Events Over The Central United States In Aogcm-Driven Regional Climate Model Simulations, Ariele Rhiane Daniel Jan 2015

Changes In Extreme Precipitation Events Over The Central United States In Aogcm-Driven Regional Climate Model Simulations, Ariele Rhiane Daniel

Graduate Theses and Dissertations

We analyze changes in extreme daily precipitation frequency using atmosphere-ocean global climate model (AOGCM) driven regional climate simulations. Nested regional climate model simulations were conducted using RegCM4.4 over the CORDEX-North America domain with 25 and 50 km grid spacing. Initial and lateral boundary conditions are taken from the HadGEM2-ES and GFDL-ESM2M AOGCMs (for RCP8.5 emissions scenario) to simulate present and future climate (1971-2000, 2041-2070). For each run, RegCM4 uses two different convection schemes: the Emanuel scheme, and a Mixed scheme which uses the Emanuel scheme over water and Grell scheme over land. These models were compared for the ...


Analysis Of Cytokinin-Induced Maize Leaf Developmental Changes And Interacting Genetic Modifiers, James Francis Cahill Jan 2015

Analysis Of Cytokinin-Induced Maize Leaf Developmental Changes And Interacting Genetic Modifiers, James Francis Cahill

Graduate Theses and Dissertations

Four distinct segments define the maize leaf along the proximal-distal axis: the proximal sheath and the distal blade, which are separated by the ligule and auricle. The process of maize leaf morphogenesis, patterning and development requires the coordination of a number of proteins and hormones. The semi-dominant gain-of-function mutant Hairy sheath frayed1 (Hsf1) disrupts a number of leaf growth parameters: (i) leaves are shorter and more narrow, (ii) an increased density of macrohairs are apparent on the abaxial sheath and adaxial blade and (iii) the normal proximal-distal leaf pattern is disrupted, resulting in outgrowths, or prongs, of ectopic sheath, auricle ...


Motivation And Retention Of Iowa’S Master Gardener Volunteers, Bryn Takle Jan 2015

Motivation And Retention Of Iowa’S Master Gardener Volunteers, Bryn Takle

Graduate Theses and Dissertations

Retention of participants in volunteer organizations has been shown to be not only a challenge, but also a great benefit to the organization. Rising costs of training and continuing education make each interaction valuable from both perspectives. Volunteer opportunities are abundant but must be meaningful and engaging for the participants in order to keep them involved. Using electronic survey software, Iowa Master Gardeners were asked to respond to a series of questions investigating 1) the current demographics of the population, 2) reasons volunteers associate with the Master Gardener program, and 3) the continuing education topics and delivery methods most preferred ...


Corn Seedling Response To Silicon Amendments In Three Iowa And One Chinese Soil, Ziying Wang Jan 2015

Corn Seedling Response To Silicon Amendments In Three Iowa And One Chinese Soil, Ziying Wang

Graduate Theses and Dissertations

Silicon is an essential element in biological systems. It is required by mammals, plants, and microorganisms. It is well studied as a component of soil mineralogy, especially in the phyllosilicate (tetrahedron) structure. However, there remains a significant need to study more about how Si affects plant growth. This study seeks to address this need in a small way. Specifically this project evaluates the likely amount of Si in three Iowa soils and one Chinese soil, and whether Si influences early corn growth (seedlings) in a pot study. The soil series of interest in Iowa are Fayette, Harps and Ida. Seedlings ...


Influence Of Corn Seeding Rate, Soil Attributes, And Topographic Characteristics On Grain Yield, Yield Components, And Grain Composition, Mark Allen Licht Jan 2015

Influence Of Corn Seeding Rate, Soil Attributes, And Topographic Characteristics On Grain Yield, Yield Components, And Grain Composition, Mark Allen Licht

Graduate Theses and Dissertations

Adoption of variable seeding rates has increased dramatically in recent years due to ability and feasibility of determining soil and topographic variability within fields. This research explores soil and topographic attribute interactions with seeding rate and the effect they have on corn yield, yield components, and grain composition. Experimental treatments included five seeding rates (61,750; 74,100; 86,450; 98,800; and 111,150 seeds ha-1) in a randomized complete block design in three central Iowa fields from 2012 to 2014. Soil samples were analyzed for available P, exchangeable K, pH, soil organic matter, cation exchange capacity, and texture ...


Seedborne Black Aspergillus Species As Maize Seedling Pathogens: Role Of Fumonisin Production And Interaction With Soilborne Pythium Species, Laura Kaelia Weieneth Jan 2015

Seedborne Black Aspergillus Species As Maize Seedling Pathogens: Role Of Fumonisin Production And Interaction With Soilborne Pythium Species, Laura Kaelia Weieneth

Graduate Theses and Dissertations

Twenty-six strains of black Aspergillus (Aspergillus section Nigri) were studied as seedling pathogens of maize. There were two major research components. The first component was an evaluation of the pathogenicity of isolates from several black Aspergillus species and a comparison of the pathogenicity of isolates with and without fumonisin production. This was accomplished by testing inoculated seeds in warm germination and cold tests, and by evaluating growth of inoculated seeds in rolled paper towel assays. In the second component, four of these species were selected for evaluation of interactions between Aspergillus and Pythium as a seedling disease complex in maize ...


Gametophytic Cross-Incompatibility In Maize: Resequencing The Ga1 Locus, Marianne Lynn Emery Jan 2015

Gametophytic Cross-Incompatibility In Maize: Resequencing The Ga1 Locus, Marianne Lynn Emery

Graduate Theses and Dissertations

Maize is an important staple crop for many countries. Culture dictates maize use, processing, and incorporation into foods. The crop has a rich history of domestication and improvement. With its relative ease of genetic manipulation, maize is considered a model crop for plant genetic experimentation. Recent biotechnological advances, as well as the completed B73 reference genome sequence, have expedited maize improvement. One such profound advance that has greatly increased profitability of maize is the use of transgenes. Despite the many benefits, transgenic plants are problematic when they contaminate transgene-free maize. Maintaining the purity of transgene-free maize is crucial, but often ...


Winter Rye Cover Crop Effect On Corn Seedling Pathogens, Lara Ann Schenck Jan 2015

Winter Rye Cover Crop Effect On Corn Seedling Pathogens, Lara Ann Schenck

Graduate Theses and Dissertations

Cover crops are a valuable management tool to reduce soil and nutrient losses while retaining moisture, improving soil organic matter content, and stabilizing soil N during the winter months when the ground is normally left fallow. Cereal rye (Secale cereale L.) is commonly used as a winter cover crop in the Midwest due to its ability to withstand cold temperatures, reduce soil erosion, and scavenge soil N. However, it has been found that a cereal rye cover crop can sometimes reduce performance and yields in the following corn (Zea mays) crop. Past studies have suggested that reduced corn growth and ...


The Co2 Concentrating Mechanism And Nitrogen Starvation Effects Under Photoautotrophic Culture Conditions Of Chlamydomonas Reinhardtii Studied By High Throughput Dna Sequencing Technology, Wei Fang Jan 2015

The Co2 Concentrating Mechanism And Nitrogen Starvation Effects Under Photoautotrophic Culture Conditions Of Chlamydomonas Reinhardtii Studied By High Throughput Dna Sequencing Technology, Wei Fang

Graduate Theses and Dissertations

The green algae species Chlamydomonas reinhardtii can acclimate to varied environmental CO2 concentration through an inducible CO2 concentration mechanism (CCM). The chloroplast stroma protein gene LCIB mutant strains exhibits an "air dier" phenotype, which demonstrated the acclimations are different in these conditions. This project first used RNA-Seq to query the Chlamydomonas reinhardtii transcriptome for regulation by CO2 and by the transcription regulator CIA5 (CCM1). Massive impacts of CIA5 and CO2 on the transcriptome were observed, and genes with distinctive expression patterns presented a rich source of candidates for new CCM components.

Two second-site mutant suppressor strains of the "air dier ...


Life Cycle Assessment (Lca) And Techno-Economic Analysis (Tea) Of Various Biosystems, Kun Xie Jan 2015

Life Cycle Assessment (Lca) And Techno-Economic Analysis (Tea) Of Various Biosystems, Kun Xie

Graduate Theses and Dissertations

The fast-growing world population prompts researchers to evaluate both environmental and economic impacts during manufacture and service processing. Distillers dried grains with solubles (DDGS) fractionation and aquaponics are two bioprocesses aiming to make full use of materials and resources. This study conducted Life cycle assessment (LCA) and Techno-economic analysis (TEA) for DDGS fractionation and tilapia-basil aquaponics.

DDGS mainly contains protein, oil, fiber, and ash. DDGS could have more economic value and wider use if it could be separated into higher protein fraction and higher fiber fraction. In our work, the optimization of three parameters of a gravity separator (side slope ...


Biosynthetically Produced Amino Acid Byproducts Can Replace Nitrogen Fertilizers For Corn Production, Juan Carlos Quezada Rivera Jan 2015

Biosynthetically Produced Amino Acid Byproducts Can Replace Nitrogen Fertilizers For Corn Production, Juan Carlos Quezada Rivera

Graduate Theses and Dissertations

Commercial biosynthesis of the amino acids tryptophan (TRP) and lysine (LYS) results in byproducts that are rich in both organic and inorganic compounds. Their nitrogen (N) content may have value as fertilizer N replacement in corn (Zea mays L.) production. We conducted a two-year field study where soil applied pure TRP, its biosynthesis byproduct and LYS byproduct were evaluated as replacements for synthetic N fertilizers in corn production. In-season plant measurements leaf area index , normalized difference vegetation index, grain quality (grain protein and oil concentration) and total N accumulation were not affected by N treatments. Additionally, TRP and LYS biosynthesis ...