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Full-Text Articles in Life Sciences

Genetic Analysis Of Flower Color Differences Between A Hummingbird-Pollinated And A Self-Pollinated Monkeyflower (Mimulus) Species, Caitlin Foster May 2020

Genetic Analysis Of Flower Color Differences Between A Hummingbird-Pollinated And A Self-Pollinated Monkeyflower (Mimulus) Species, Caitlin Foster

University Scholar Projects

Flower color plays an important role in pollinator discrimination and speciation. Understanding the genetic contributions to flower color differences between two closely related species, Mimulus cardinalis and Mimulus parishii, can improve understanding of how they developed different pollination syndromes and diverged from a recent common ancestor. M. cardinalis is hummingbird-pollinated and has large, bright red flowers while M. parishii is self-pollinated and has small, pale pink flowers. An F2 hybrid population between these two species was created to establish a platform for analysis of the genetic architecture controlling the differences in anthocyanin pigmentation. Statistical analysis of anthocyanin concentration distribution in ...


Utilizing Random Regression Models For Genomic Prediction Of A Longitudinal Trait Derived From High‐Throughput Phenotyping, Malachy T. Campbell, Harkamal Walia, Gota Morota Jul 2018

Utilizing Random Regression Models For Genomic Prediction Of A Longitudinal Trait Derived From High‐Throughput Phenotyping, Malachy T. Campbell, Harkamal Walia, Gota Morota

Agronomy & Horticulture -- Faculty Publications

The accessibility of high‐throughput phenotyping platforms in both the greenhouse and field, as well as the relatively low cost of unmanned aerial vehicles, has provided researchers with an effective means to characterize large populations throughout the growing season. These longitudinal phenotypes can provide important insight into plant development and responses to the environment. Despite the growing use of these new phenotyping approaches in plant breeding, the use of genomic prediction models for longitudinal phenotypes is limited in major crop species. The objective of this study was to demonstrate the utility of random regression (RR) models using Legendre polynomials for ...


Genetic Diversity And Distinctness Of Wild Nebraska Hops And Hop Cultivars (Humulus Lupulus L.), Megan Franklin Mar 2018

Genetic Diversity And Distinctness Of Wild Nebraska Hops And Hop Cultivars (Humulus Lupulus L.), Megan Franklin

Honors Theses, University of Nebraska-Lincoln

Background Commercial hop (Humulus lupulus) cultivars that are being grown in the Midwest are not performing as successfully as when they are grown in the Pacific Northwest, the region to which they are adapted. To increase adaptation to the Midwest environment, one strategy is to draw from the genetic pool of wild native Midwest hops, which have developed genes that allow them to grow successfully in this environment. Wild hop plants that are genetically distinct from commercial cultivars are likely to have more adaptations, such as pest/disease resistance and drought tolerance, which can be bred into commercial lines. The ...


Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind Jan 2018

Natural And Anthropogenic Drivers Of Tree Evolutionary Dynamics, Brandon M. Lind

Theses and Dissertations

Species of trees inhabit diverse and heterogeneous environments, and often play important ecological roles in such communities. As a result of their vast ecological breadth, trees have become adapted to various environmental pressures. In this dissertation I examine various environmental factors that drive evolutionary dynamics in threePinusspecies in California and Nevada, USA. In chapter two, I assess the role of management influence of thinning, fire, and their interaction on fine-scale gene flow within fire-suppressed populations of Pinus lambertiana, a historically dominant and ecologically important member of mixed-conifer forests of the Sierra Nevada, California. Here, I find evidence that ...


Uncovering Tasselsheath3. A Genomic And Phenotypic Analysis Of A Maize Floral Mutant., Thompson Zhang Oct 2017

Uncovering Tasselsheath3. A Genomic And Phenotypic Analysis Of A Maize Floral Mutant., Thompson Zhang

Masters Theses

In the modern era, maize has become the most successful crop grown in the United States. According to the USDA over 90 million acres of land are planted to corn and 96.2% of the U.S feed grain production is made up of the cereal. Part of the success of maize is due to its floral architecture, and its pollination technique in which the flower opens, exposing stamens containing pollen into the air. A unique organ called the lodicule functions as a release mechanism, forcing the flower to open. Lodicules from grasses and eudicot petals are homologous, yet there ...


Principles Of Biology, Robert Bear, David Rintoul, Bruce Snyder, Martha Smith-Caldas, Christopher Herren, Eva Horne Jan 2016

Principles Of Biology, Robert Bear, David Rintoul, Bruce Snyder, Martha Smith-Caldas, Christopher Herren, Eva Horne

Open Access Textbooks

This textbook is designed specifically for Kansas State's Biology 198 Class. The course is taught using the studio approach and based on active learning. The studio manual contains all of the learning objectives for each class period and is the record of all student activities. Hence, this textbook is more of a reference tool while the studio manual is the learning tool.

The textbook was originally published and is also available to download at http://cnx.org/contents/db89c8f8-a27c-4685-ad2a-19d11a2a7e2e@24.1.It is licensed under a Creative Commons Attribution License 4.0 license.


Regulation Of Shoot Development In Maize Via Brassinosteroid Signaling, Gokhan Kir Jan 2015

Regulation Of Shoot Development In Maize Via Brassinosteroid Signaling, Gokhan Kir

Graduate Theses and Dissertations

Brassinosteroids (BR) are a class of phytohormones with many important roles in plant growth and development. Compared to other model organisms BR signaling is poorly understood in maize. To study BR signaling's role in maize growth and development we suppressed two members of the BR signaling pathway, BRI1 and BIN2, by RNAi approach. BLAST searches and phylogenetic analyses suggested that there are two BRI1 copies and three BRI1-like genes (BRL) homologs in maize. bri1b, which is located on chr 5, was incomplete in databases, but via subsequent cloning and sequencing was found to be an intact and expressed gene ...


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 ...


Functional Conservation Of The Capacity For Ent-Kaurene Biosynthesis And An Associated Operon In Certain Rhizobia, David M. Hershey, Xuan Lu, Jiachen Zi, Reuben J. Peters Jan 2014

Functional Conservation Of The Capacity For Ent-Kaurene Biosynthesis And An Associated Operon In Certain Rhizobia, David M. Hershey, Xuan Lu, Jiachen Zi, Reuben J. Peters

Biochemistry, Biophysics and Molecular Biology Publications

Bacterial interactions with plants are accompanied by complex signal exchange processes. Previously, the nitrogen-fixing symbiotic (rhizo)bacterium Bradyrhizobium japonicum was found to carry adjacent genes encoding two sequentially acting diterpene cyclases that together transform geranylgeranyl diphosphate to ent-kaurene, the olefin precursor to the gibberellin plant hormones. Species from the three other major genera of rhizobia were found to have homologous terpene synthase genes. Cloning and functional characterization of a representative set of these enzymes confirmed the capacity of each genus to produce ent-kaurene. Moreover, comparison of their genomic context revealed that these diterpene synthases are found in a conserved operon ...


Dirigent Domain-Containing Protein Is Part Of The Machinery Required For Formation Of The Lignin-Based Casparian Strip In The Root, Prashant S. Hosmani, Takehiro Kamiya, John Danku, Sadaf Naseer, Niko Geldner, Mary Lou Guerinot, David Salt Aug 2013

Dirigent Domain-Containing Protein Is Part Of The Machinery Required For Formation Of The Lignin-Based Casparian Strip In The Root, Prashant S. Hosmani, Takehiro Kamiya, John Danku, Sadaf Naseer, Niko Geldner, Mary Lou Guerinot, David Salt

Open Dartmouth: Published works by Dartmouth faculty

The endodermis acts as a "second skin" in plant roots by providing the cellular control necessary for the selective entry of water and solutes into the vascular system. To enable such control, Casparian strips span the cell wall of adjacent endodermal cells to form a tight junction that blocks extracellular diffusion across the endodermis. This junction is composed of lignin that is polymerized by oxidative coupling of monolignols through the action of a NADPH oxidase and peroxidases. Casparian strip domain proteins (CASPs) correctly position this biosynthetic machinery by forming a protein scaffold in the plasma membrane at the site where ...


The Effects Of Cytokinin On The Transcriptional Regulation Of Pin Expression In Arabidopsis Thaliana, Elizabeth Burgess Jul 2012

The Effects Of Cytokinin On The Transcriptional Regulation Of Pin Expression In Arabidopsis Thaliana, Elizabeth Burgess

Honors Theses and Capstones

The processes of cell division and differentiation are critical to the development of any multicellular organism. During the formation of plant roots these processes take place at a region of the root tip called the meristem. Cytokinin and auxin are two plant growth hormones that influence this process. Although these two growth hormones are both necessary they also appear in many ways to have an antagonistic relationship. As meristematic root cells undergo differentiation they cease dividing. It has been proposed that the size of the root meristem and thus the overall rate of root growth are determined by the balance ...


Structural Variation In The Maize Genome, Kai Ying Jan 2012

Structural Variation In The Maize Genome, Kai Ying

Graduate Theses and Dissertations

Whole-genome array-based comparative genomic hybridization (aCGH) was used to study structural variation between two elite maize inbred lines, B73 and Mo17. Several hundred Copy Number Variants (CNVs) as well as several thousands of Present Absent Variants (PAVs) were discovered. This high level of structural variation among haplotypes is unprecedented among higher eukaryotes. Haplotype-specific PAVs that encompass hundreds of single-copy, expressed genes may contribute to heterosis and the extraordinary phenotypic diversity of this important crop. aCGH can be also used for genotyping complex genomes, such as that of maize. Approximately 200,000 oligonucleotide probes whose hybridization signals exhibit significant differences between ...


Transcriptomic Characterization Of A Synergistic Genetic Interaction During Carpel Margin Meristem Development In Arabidopsis Thaliana, April N. Wynn, Elizabeth E. Rueschhoff, Robert G. Franks Oct 2011

Transcriptomic Characterization Of A Synergistic Genetic Interaction During Carpel Margin Meristem Development In Arabidopsis Thaliana, April N. Wynn, Elizabeth E. Rueschhoff, Robert G. Franks

Biological Sciences Research

In flowering plants the gynoecium is the female reproductive structure. In Arabidopsis thalianaovules initiate within the developing gynoecium from meristematic tissue located along the margins of the floral carpels. When fertilized the ovules will develop into seeds. SEUSS (SEU) and AINTEGUMENTA (ANT) encode transcriptional regulators that are critical for the proper formation of ovules from the carpel margin meristem (CMM). The synergistic loss of ovule initiation observed in the seu ant double mutant suggests that SEU and ANT share overlapping functions during CMM development. However the molecular mechanism underlying this synergistic interaction is unknown. Using the ATH1 transcriptomics platform ...


Understanding The Biological Activity Of Hypericum Species Through Metabolomics Studies, Matthew Lee Hillwig Jan 2008

Understanding The Biological Activity Of Hypericum Species Through Metabolomics Studies, Matthew Lee Hillwig

Retrospective Theses and Dissertations

The Hypericum genus contains plants which biosynthesize various polyketides with various known and unknown biological and medicinal activities. However, many Hypericum species have not been chemically or biochemically characterized. These species represent an opportunity for understanding chemical ecology and for new drug discovery research. Acyl-phloroglucinols are of particular interest since they are the most diverse class of specialized metabolites in Hypericum. We used analytical methods such as HPLC, LC-MS and 2-D NMR to screen Hypericum species for metabolite diversity. One species, H. gentianoides, was investigated further based on its historical use by Native Americans and its unique metabolite fingerprint. This ...


Functional Characterization Of Arabidopsis Sorting Nexin Atsnx2b, Nguyen Phan Jan 2008

Functional Characterization Of Arabidopsis Sorting Nexin Atsnx2b, Nguyen Phan

Retrospective Theses and Dissertations

Sorting nexins are conserved proteins that function in vesicular trafficking and are defined by the presence of a phox (PX) domain. Here we present the characterization of Arabidopsis thaliana sorting nexin AtSNX2b. The ubiquitously-expressed sorting nexin is a peripherally-associated membrane protein whose PX domain binds to phosphatidylinositol 3-phosphate in vitro. AtSNX2b localizes to the trans-Golgi network (TGN), prevacuolar compartment and endosomes. Overexpression of GFP-tagged AtSNX2b produces enlarged GFP-labeled compartments that can be also labeled by the endocytic tracer FM4-64, while untagged AtSNX2b overexpression generates compartments which are not as large. Endocytic trafficking of FM4-64 is arrested in cells overexpressing AtSNX2b ...


2c Dna Content Values In Amaranthus (Amaranthaceae) [Abstract], Donald B. Pratt, Shalini N. Jhangiani, Robert J. Wiggers Jan 2008

2c Dna Content Values In Amaranthus (Amaranthaceae) [Abstract], Donald B. Pratt, Shalini N. Jhangiani, Robert J. Wiggers

Faculty Publications

No abstract provided.


Development And Characterization Of Microsatellite Markers For The Grain Amaranths [Abstract], Melanie A. Mallory, Rozaura V. Hall, Andrea R. Mcnabb, Donald B. Pratt, Eric N. Jellen, Peter J. Maughan Jan 2008

Development And Characterization Of Microsatellite Markers For The Grain Amaranths [Abstract], Melanie A. Mallory, Rozaura V. Hall, Andrea R. Mcnabb, Donald B. Pratt, Eric N. Jellen, Peter J. Maughan

Faculty Publications

No abstract provided.


A Strong Constitutive Ethylene-Response Phenotype Conferred On Arabidopsis Plants Containing Null Mutations In The Ethylene Receptors Etr1 And Ers1, Xiang Qu, Brenda P. Hall, Zhiyong Gao, G. Eric Schaller Jan 2007

A Strong Constitutive Ethylene-Response Phenotype Conferred On Arabidopsis Plants Containing Null Mutations In The Ethylene Receptors Etr1 And Ers1, Xiang Qu, Brenda P. Hall, Zhiyong Gao, G. Eric Schaller

Open Dartmouth: Published works by Dartmouth faculty

The ethylene receptor family of Arabidopsis consists of five members, falling into two subfamilies. Subfamily 1 is composed of ETR1 and ERS1, and subfamily 2 is composed of ETR2, ERS2, and EIN4. Although mutations have been isolated in the genes encoding all five family members, the only previous insertion allele of ERS1 (ers1-2) is a partial loss-of-function mutation based on our analysis. The purpose of this study was to determine the extent of signaling mediated by subfamily-1 ethylene receptors through isolation and characterization of null mutations.


A Study Of The Impact Of Mazie Sbe I On The [Alpha]-Polyglucan Produced In Synechocystis Sp. Strain Pcc 6803, Shayani Deborah Nesaranjani Pieris Jan 2007

A Study Of The Impact Of Mazie Sbe I On The [Alpha]-Polyglucan Produced In Synechocystis Sp. Strain Pcc 6803, Shayani Deborah Nesaranjani Pieris

Retrospective Theses and Dissertations

Starch is a biopolymer synthesized primarily in plants and is made of alpha-1,4 linked glucose chains with alpha-1,6 glycosidic bonds at branch points. Amylose and amylopectin, the component molecules of starch are essentially linear and 4-5% branched respectively. Amylopectin, thought to be responsible for the semi-crystalline nature of starch, is chemically similar but physically distinct from water-soluble glycogen. Amylopectin is distinct from glycogen in having longer chains, fewer branch points and a clustered branching pattern. The hypothesis that the presence of a branching enzyme that can transfer long branches will facilitate the formation and perpetuation of a cluster ...


Function Of Autophagy In Development And Abiotic Stress Tolerance In Arabidopsis Thaliana , Yan Xiong Jan 2006

Function Of Autophagy In Development And Abiotic Stress Tolerance In Arabidopsis Thaliana , Yan Xiong

Retrospective Theses and Dissertations

Autophagy is a process in which cytoplasmic components are degraded in the vacuole. It occurs when organisms are subjected to environmental stress conditions or during certain stages of development. Upon induction of autophagy, a portion of cytoplasm is surrounded by a double membrane structure to form an autophagosome. The outer membrane of the autophagosome then fuses with the vacuole and the inner membrane and its contents are degraded by vacuolar hydrolases. The morphological characteristics of autophagy have been observed in plants for decades and several autophagy defective mutants have been isolated recently; however, little is known about the molecular mechanism ...


The Roles Of Aldehyde Dehydrogenases (Aldhs) In Acetyl-Coa Biosynthesis And Root Elongation In Arabidopsis , Yanling Wei Jan 2006

The Roles Of Aldehyde Dehydrogenases (Aldhs) In Acetyl-Coa Biosynthesis And Root Elongation In Arabidopsis , Yanling Wei

Retrospective Theses and Dissertations

Aldehyde dehydrogenases (ALDHs, EC 1.2.1) oxidize aldehydes into carboxylic acids, and thus are important in regulating the level of toxic aldehydes. ALDHs from eukaryotes were classified into more than 20 families. In mammals Family 2 ALDHs detoxify acetaldehyde and a similar function has been suggested in plants. Specifically, it has been hypothesized that plant Family 2 ALDHs oxidize acetaldehyde generated via ethanolic fermentation and produce acetate for acetyl-CoA biosynthesis through acetyl-CoA synthetase (ACS) in plastids, similar to the yeast pathway termed the "pyruvate dehydrogenase (PDH) bypass". Arabidopsis. thaliana contains three Family 2 ALDHs, two of which are mitochondrial ...


Carbohydrate Partitioning And Photosynthesis In Arabidopsis Thaliana , Dan Joseph Stessman Jan 2004

Carbohydrate Partitioning And Photosynthesis In Arabidopsis Thaliana , Dan Joseph Stessman

Retrospective Theses and Dissertations

To characterize carbohydrate partitioning and photosynthesis in Arabidopsis thaliana we examined three different lines: wild type Columbia ecotype, immutans, and T-DNA knockouts of vacuolar acid invertase. Wild type plants displayed decreasing photosynthesis from the beginning of leaf expansion through senescence. Chlorophyll, total soluble protein, and expression of LhcB also declined in a similar fashion. Pulse-label feeding of 14C showed a peak flux into glucose and fructose coincident with full leaf expansion a large decrease in LhcB expression. However, flux of 14C into the different carbohydrate fractions did not reflect carbohydrate pool sizes. The conclusion was that flux into the different ...


Investigating The Influence Of Cadmium Stress On Glutathione Metabolism Utilizing Mutant And Transgenic Arabidopsis Plants , Annita Gatherum Peterson Jan 2004

Investigating The Influence Of Cadmium Stress On Glutathione Metabolism Utilizing Mutant And Transgenic Arabidopsis Plants , Annita Gatherum Peterson

Retrospective Theses and Dissertations

Glutathione (GSH) has long been known to be an essential molecule in a number of important basic cellular functions including detoxification of reactive oxygen species, transport and storage of organic sulfur, and regulation of the cell cycle. Furthermore, GSH is essential in the detoxification of some heavy metals including cadmium through the production of phytochelatins. Because the accounts of heavy metal pollution are increasing due to human activities, heavy metal toxicity in plants is an important topic of study. To investigate the role of GSH-related functions in response to cadmium exposure I examined three distinct levels of GSH involvement in ...


Crop Updates 2000 - Weeds, Vanessa Stewart, David Minkey, Abul Hashem, Glen Riethmuller, Martin Harries, Peter Newman, Cameron Weeks, Harmohinder S. Dhammu, Aik Cheam, David Bowran, Terry Piper, Alexandra Wallace, Bill Roy, Keith L. Devenish, Lisa J. Leaver, Brad Rayner, Mike Collins, Marta Monardino, David Pannell, Stephen Powles, Sally Peltzer, Michael Walsh, Charles Boyle, P. Neve, D. Lorraine-Colwill, C. Preston, Art Diggle, Rick Llewellyn, Ryan Duane, Siew Lee, David Nicholson, Peter Carlton, Stewart Smith, Bill Crabtree, Gordon Cumming, David Cameron, Mike Jackson, Scott Paton, John R. Peirce, Greg Shea Feb 2000

Crop Updates 2000 - Weeds, Vanessa Stewart, David Minkey, Abul Hashem, Glen Riethmuller, Martin Harries, Peter Newman, Cameron Weeks, Harmohinder S. Dhammu, Aik Cheam, David Bowran, Terry Piper, Alexandra Wallace, Bill Roy, Keith L. Devenish, Lisa J. Leaver, Brad Rayner, Mike Collins, Marta Monardino, David Pannell, Stephen Powles, Sally Peltzer, Michael Walsh, Charles Boyle, P. Neve, D. Lorraine-Colwill, C. Preston, Art Diggle, Rick Llewellyn, Ryan Duane, Siew Lee, David Nicholson, Peter Carlton, Stewart Smith, Bill Crabtree, Gordon Cumming, David Cameron, Mike Jackson, Scott Paton, John R. Peirce, Greg Shea

Crop Updates

This session covers thirty six papers from different authors:

INTRODUCTION, Vanessa Stewart Agriculture Western Australia

INTEGRATED WEED MANAGEMENT

  1. Effect of seeding density, row spacing and Trifluralin on the competitive ability of Annual Ryegrass in a minimum tillage system, David Minkey, Abul Hashem, Glen Riethmuller and Martin Harries, Agriculture Western Australia

  2. High wheat seeding rates coupled with narrow row spacing increases yield and suppresses grass, Peter Newman1 and Cameron Weeks2,1Agronomist, Elders Limited 2Mingenew/Irwin Group

  3. Resistant ryegrass management in a wheat – lupin rotation, Abul Hashem, Harmohinder S. Dhammu, Aik Cheam, David Bowran and Terry Piper, Agriculture ...