Plant Biology Commons^™

Poplar Allene Oxide Synthase 1 Gene Promoter Drives Rapid And Localized Expression By Wounding, Bin Lei, Christopher J. Frost, Tao Xu, Joshua Herr, John E. Carlson, Haiying Liang

Department of Plant Pathology: Faculty Publications

Promoters play critical roles in controlling the transcription of genes and are important as tools to drive heterologous expression for biotechnological applications. In addition to core transcription factor-binding motifs that assist in the binding of RNA polymerases, there are specific nucleotide sequences in a promoter region to allow regulation of gene expression. The allene oxide synthase (AOS) gene family are cytochrome P450s that are responsive to a variety of environmental stress, making them good candidates for the discovery of inducible promoters. Populus AOS homologs separate phylogenetically into two clades. Based on the 19 promoter motifs with significant abundance differences between …

Pratylenchus Smoliki, A New Nematode Species (Pratylenchidae: Tylenchomorpha) From The Great Plains Region Of North America, Thomas Powers, Timothy Todd, Tim Harris, Rebecca Higgins, Ann Macguidwin, Peter Mullin, Mehmet Ozbayrak, Kirsten Powers, Kanan Sakai

Department of Plant Pathology: Faculty Publications

Pratylenchus smoliki is a new species of root-lesion nematode described from corn-soybean production fields in the Central Great Plains of North America. It is characterized by populations with relatively abundant males, two lip annuli, females with a round functional spermatheca and a conoid to subcylindrical tail with a non-crenate, smooth terminus. In host preference tests, corn and wheat produce the largest nematode populations, whereas sorghum and soybeans produce less than 20% the numbers observed on corn. Scanning electron microscopy reveals that the en face patterns compare to those seen in Pratylenchus pseudocoffeae, P. scribneri, P. hexincisus, and …

Studying Morphological, Physiological, And Molecular Regulation Of Stomatal Conductance And Its Relationship To Water Use Efficiency In Alfalfa, Surbhi Gupta

Electronic Theses and Dissertations

Alfalfa (Medicago sativa), being a leguminous, highly fibrous, and proteinaceous plant has always been one of the top choices for the forage production but has high cost of irrigation in many dry and warm areas such as California and Arizona. Thus, a reduction of irrigation by using the higher water use efficiency (WUE) varieties can help the growers in reducing the cost and is critical for sustainable agriculture production. WUE is closely related to water loss through transpiring stomata. A study in our lab reported that Riverside (RS) an alfalfa genotype that has naturized in the national grassland in South …

Identification Of Loci Influencing Teosinte Crossing Barrier 1 (Tcb1) Efficacy In Maize By Quantitative Trait Loci (Qtl) Mapping And Genome-Wide Association Study (Gwas), Namrata Maharjan

Electronic Theses and Dissertations

Pollen cross-contamination has been a major problem for maize breeders. Various mechanical methods applied to avoid the contaminations are ineffective. The genetic factors related to maize fertilization can be used to develop an effective method to prevent pollen contamination. Pollen rejection ability controlled by Teosinte crossing barrier 1 (Tcb1) is such a genetic system. Silks possessing dominant Tcb1-s reject pollen possessing the recessive allele (tcb1). Successful fertilization occurs when Tcb1-s pollen falls upon tcb1 silks. The efficacy of dominant Tcb1-s was, however, reduced when repeatedly backcross with maize inbred lines, which suggests that there are modifiers to Tcb1-s. To find …

A Biocontrol Pesticide Derived From Mycovirus-Infected Sclerotinia Sclerotiorum Can Induce Plant Resistance, Connor Pedersen

Electronic Theses and Dissertations

Soybean leaf-associated gemycircularvirus-1 (SlaGemV-1) is a novel mycovirus discovered through the metagenomic sequencing of soybean leaves which is capable of inducing hypovirulence in the highly pathogenic fungus Sclerotinia sclerotiorum. RNASeq analysis techniques were used to determine the transcriptional changes caused by the infection of virus in S. sclerotiorum, as well as the transcriptional changes in Glycine max caused by the colonization of hypovirulent, SlaGemV-1-infected S. sclerotiorum. RNASeq results indicate that viral infection leading to hypovirulence may attenuate expression of genes relating to cell wall synthesis, microtubule formation, and metabolism of steroids and natural antibiotics. Cytochrome P450-related genes, kinesin domain genes, …

That Code-Switching Switchgrass - A Root Analysis Of Two Ecotypes Of P. Virgatum Under Temperture Variations, Hannah Johnson

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Impact Of Arbuscular Mycorrhizal Fungi On Conyza Canadensis Drought Responses And Possible Mechanisms, Kian G.M. Speck, Ylva Lekberg, Anna Sala

Undergraduate Theses, Professional Papers, and Capstone Artifacts

• Arbuscular mycorrhizal fungi (AMF) are important plant mutualists that can facilitate plant responses to various environmental stressors, such as drought. A plant that may benefit from AMF-induced drought tolerance is Conyza canadensis due to its ability to thrive in dry conditions and its high colonization rate. However, no studies have researched C. canadensis in this context and the exact mechanisms of AMF-induced drought tolerance are still unknown.
• To better understand if and how AMF facilitate drought response in C. canadensis, we conducted a greenhouse experiment comparing the response of mycorrhizal and non-mycorrhizal plants to three watering levels. We measured …

James B Beard: The Father Of Contemporary Turfgrass Science, G.K. Stahnke, P.E. Rieke, Robert C. Shearman, Roch E. Gaussoin, David Kopec

Department of Agronomy and Horticulture: Faculty Publications

James B Beard (24 Sept 1935 to 8 May 2018) can rightly be considered the “Father” of contemporary turfgrass science. During his career, he was known for setting a standard that provided the foundation for turfgrass science through his thorough approach to research, teaching, mentoring and communications. The books he published outlined a vision for an evolving scientific discipline. He trained and mentored >45 domestic and international doctoral and master students and numerous post-doctoral trainees, who in turn continued to raise the quality of contemporary turfgrass science in the USA and internationally. He led the effort to change the name …

Elucidation Of Multi-Origin Inula Helenium L. For Antimicrobial Activity And Heavy Metal Profiling As An Exemplar For The Use And Regulation Of Plants As Antibiotics., Ciara Ruth Kenny

Theses

An impending post-antibiotic era looms, thus new sources of therapeutic chemical entities are crucial to sustain effective antimicrobial chemotherapy worldwide. Plant natural products are a source of accessible, structurally diverse compounds that provide therapeutic potential. The pharmacological applications of plants in medicine can be guided by the attestation of traditional use or the application of this knowledge to uncover new leads in the drug discovery process. The range of modified in vitro methods commonly used to investigate preclinical antimicrobial efficacy of plant-derived natural products, and the associated limitations and challenges in the provision of new antimicrobial drugs from plants is …

Impacts Of Rock Climbing On Lichen And Bryophyte Communities At Mclellan Rocks And Sharon Climbing Areas, Spokane County, Wa, Giovanna M. Bishop

EWU Masters Thesis Collection

Saxicolous lichens and bryophytes dominate cliff communities of Eastern Washington State. A recent rise in the outdoor recreation of rock climbing has caused major concerns over its potential negative impacts on cliff-dwelling biodiversity. To better understand how rock climbing is impacting lichen, bryophyte and vascular plant communities in Spokane, WA, I surveyed two sites: McLellan Rocks and Rocks of Sharon, for the abundance, richness and diversity of lichens, bryophytes and vascular plants. Sixteen paired transects consisting of a climbed route and the unclimbed adjacent cliff face, with eight plots per transect for a total of 256, 0.5m2 plots were surveyed …

Remnant Assessment And Soil Inoculation To Inform Large-Scale Prairie Restoration At Eastern Washington University, Erik E. Peterson

EWU Masters Thesis Collection

The Palouse Prairie of Eastern Washington and Western Idaho, characterized by rolling hills of deep loess soil, is one of the most endangered ecosystems in the world, with more than 99% converted to tilled farmland. To mitigate this loss, Eastern Washington University has begun prairie restoration on a tilled wheat field adjacent to campus, in the northern extent of the Palouse Prairie Ecoregion. However, effective restoration requires understanding reference conditions, and there are relatively few studies of remnant prairie plant communities or soils, particularly in the Northern Palouse. From north to south in the Palouse Prairie Ecoregion, there are gradients …

The Impacts Of Imazapic On Garlic Mustard And Non-Target Forest Floor Vegetation In Central Kentucky’S Hardwood Forests, Pavan Kumar Podapati

Theses and Dissertations--Forestry and Natural Resources

Alliaria petiolata is an invasive biennial herb that poses a substantial threat to various ecosystems across the United States. Imazapic herbicide can control A. petiolata infestations, but there is limited peer-reviewed data on impacts of pre-emergent imazapic spraying to forest floor communities. This research examined the impacts of pre-emergent imazapic (0.84 kg/ha) with Pentra-Bark® surfactant on ground cover of A. petiolata and the spring perennials Claytonia virginica and Erigenia bulbosa. Experimental populations in randomized blocks within two forest stands in central Kentucky received the following treatments at 0.84 kg ai/ha: imazapic with Pentra-Bark®, glyphosate with Pentra-Bark®, Pentra-Bark® alone, and …

Environmental Data: Geospatial And Elevation Data, Albert J. Burky, Julia I. Chapman, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

GPS Coordinates, Elevation, and Distance to Edge data for 32 sample plots in Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Seedling Growth And Soil Chemistry In A Chronosequence Of Forest Restoration From Agriculture, Michaela J. Woods, Sarah J. Frankenberg, Joseph R. Juodvalkis, Mary C. Lloyd, Meredith Cobb, Ryan Mcewan

Five Rivers MetroParks Collaboration Data Archive

Soils were collected from forest restorations that were 0, 7, 10, 50 and 100 years old and assessed for soil nutrients, chemistry, and enzymatic activity. Quercus macrocarpa seedlings were planted in each soil type, after 5 months of growth seedlings were destructively harvested. Seedling mass and the colonization rate of their roots by ectomycorrhizal fungi are reported.

The photo accompanying this data collection is of the researchers' germinating Quercus macrocarpa seeds.

Does Biochar Improve All Soil Ecosystem Services?, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

Biochar is considered to sequester C and deliver other soil ecosystem services, but an overview that synthesizes the current knowledge of biochar implications on all essential soil ecosystem services is difficult to find in the ample biochar literature. Most previous research and review articles on this topic focused on a single ecosystem service and did not integrate all essential soil ecosystem services. This overview paper (1) synthesizes the impacts of biochar on water and wind erosion, C sequestration, soil water, nutrient leaching, soil fertility, crop yields, and other soil ecosystem services based on published literature and (2) highlights remaining research …

Representativeness Of Eddy-Covariance Flux Footprints For Areas Surrounding Ameriflux Sites, Housen Chu, Timothy Arkebauer, Dave P. Billesbach, Hideki Kobayashi, Thomas J. Kolbe, Gregory Starr, Andrew Suyker, 63 Other Coauthors

Department of Agronomy and Horticulture: Faculty Publications

Large datasets of greenhouse gas and energy surface-atmosphere fluxes measured with the eddy-covariance technique (e.g., FLUXNET2015, AmeriFlux BASE) are widely used to benchmark models and remote-sensing products. This study addresses one of the major challenges facing model-data integration: To what spatial extent do flux measurements taken at individual eddy-covariance sites reflect model- or satellite-based grid cells? We evaluate flux footprints—the temporally dynamic source areas that contribute to measured fluxes—and the representativeness of these footprints for target areas (e.g., within 250–3000 m radii around flux towers) that are often used in flux-data synthesis and modeling studies. We examine the land-cover composition …

Guidelines For The Use And Interpretation Of Assays For Monitoring Autophagy (4th Edition), Daniel Klionsky, Rodrigo Franco, Guangchao Sun, Richard Wilson, More Than 2000 Coauthors

Department of Agronomy and Horticulture: Faculty Publications

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to …

Roles Of Non-Frankia Bacteria In Root Nodule Formation And Function In Alnus Sp., Kelsey Christine Mercurio

Honors Theses and Capstones

Plant roots are home to a wide variety of beneficial microbes; understanding and optimizing plant-microbe interactions may be critical to enhance global food security in a sustainable, equitable way. With the help of their nitrogen-fixing bacterial partner, Frankia, actinorhizal plants form symbiotic root nodules and play important roles in agroforestry and land reclamation. However, Frankia does not live alone in nodules, and the other microbial residents may contribute to nodule formation and function. We collected root nodules from alder trees (Alnus sp.) in 2018 and 2019, then isolated DNA and individual bacterial strains to characterize the nodule microbial …

The Mechanisms And Consequences Of Shrub Encroachment On The Virginia Barrier Islands, Lauren K. Wood

Theses and Dissertations

Shrub encroachment is a global phenomenon driven by direct and indirect anthropogenic influence which alters plant communities and ecosystem function. Many studies have investigated drivers and consequences of woody plant establishment, but mesic landscapes are underrepresented in the literature. My objective was to assess the mechanisms of Morella cerifera encroachment into coastal mesic grassland, the potential for self-reinforcement, and consequences on community composition, nutrients, and landscape productivity. I studied temperature and water microclimate modification by Morella cerifera presence and removal to understand ecosystem engineering and community composition changes. Additionally, I examined the influence of shrubs on surrounding grassland species traits …

Stop Helping Pathogens: Engineering Plant Susceptibility Genes For Durable Resistance, Hernan Garcia-Ruiz, Boris Szurek, Guido Van Den Ackerveken

Department of Plant Pathology: Faculty Publications

Alternatives to protect crops against diseases are desperately needed to secure world food production and make agriculture more sustainable. Genetic resistance to pathogens utilized so far is mostly based on single dominant resistance genes that mediate specific recognition of invaders and that is often rapidly broken by pathogen variants. Perturbation of plant susceptibility (S) genes offers an alternative providing plants with recessive resistance that is proposed to be more durable. S genes enable the establishment of plant disease, and their inactivation provides opportunities for resistance breeding of crops. However, loss of S gene function can have pleiotropic effects. Developments in …

Moving The Needle On Prairie Conservation: A Palouse Prairie Restoration/Reconstruction Needs Assessment And The Effect Of Intra-Annual Soil Moisture Changes On Balsamroot Seedling Establishment, Sarah Hill

EWU Masters Thesis Collection

The Palouse prairie of Eastern Washington and Western Idaho is one of the most endangered ecosystems in the United States. After 140 years of intensive agriculture, less than 1% of prairie habitat remains, making Palouse prairie conservation and restoration a critical need. This study sought to: 1) conduct a thorough needs assessment for Palouse prairie restoration and reconstruction, identifying challenges and opportunities that when addressed, could increase Palouse prairie restoration successes, and 2) gain insight into the effects of intra-annual soil moisture fluctuations on the seedling establishment of Arrowleaf balsamroot (Balsamorhiza sagittata), since establishment of slow growing perennial species like …

Continuous In Situ Soil Nitrate Sensors: The Importance Of High-Resolution Measurements Across Time And A Comparison With Salt Extraction-Based Methods, Yunjiao Zhu, Yuncong Chen, Md. Azahar Ali, Liang Dong, Xinran Wang, Sotirios V. Archontoulis, James Schnable, Michael J. Castellano

Department of Agronomy and Horticulture: Faculty Publications

Soil NO₃^– affects microbial processes, plant productivity, and environmental N losses. However, the ability to measure soil NO₃^– is limited by labor-intensive sampling and laboratory analyses. Hence, temporal variation in soil solution NO₃^– concentration is poorly understood. We evaluated a new potentiometric sensor that continuously measures soil solution NO₃^– concentration with unprecedented specificity due to a novel membrane that serves as a barrier to interfering anions. First, we compared sensor and salt extraction-based measurements of soil NO₃^– in well-controlled laboratory conditions. Second, using 60 d of in situ soil NO …

How Wetland Plants Deal With Stress, Taylor M. Sloey

Biological Sciences Faculty Publications

We all get stressed. To deal with that stress, some of us may exercise, take a bubble bath, cry, or simply leave the stressful situation. But how can you cope with stress if you are rooted in place? Plants that live in estuaries are exposed to many types of stresses from the environment, including flooding, high salt levels, low soil oxygen, and waves. Fortunately, wetland plants have developed ways to survive within these conditions, from excreting salt, to growing faster, to even breaking down cell walls to maximize air flow. Plants can tolerate different levels of stress depending on their …

Community Diversity Influences Selection On Nutrient Resorption In Panicum Virgatum, Michael J. Lashbrook

Dissertations and Theses @ UNI

Panicum virgatum L. (switchgrass) is a bioenergy crop shown to conserve and recycle nutrients through a process known as nutrient resorption. While there are many studies looking at various aspects of nutrient cycling in switchgrass, it remains unclear whether selection is acting upon increased nutrient resorption in this species. Further, there are no phenotypic selection studies coupling empirical sexual and asexual reproduction data.

A field study and a modeling study were conducted to determine phenotypic selection on nutrient resorption and the influence of resorption on asexual reproduction in switchgrass. For the field study of phenotypic selection, I hypothesized selection favors …

Efficacy And Mechanism Of Acs811 In Tomato Immune Responses, Layne Ellen Harris

Theses and Dissertations--Plant and Soil Sciences

Biologicals are increasingly becoming an important part of sustainable integrated pest management in agricultural crop production and encompass a wide variety of products with varying degrees of efficacy and available research data. As biologicals become more integrated into commercial production systems, it is critical to rigorously evaluate biological product efficacy and mode(s) of action in crops. The better that biologicals are understood in terms of effective application, integration into commercial programs, and their specific mechanisms in crop growth and protection, then the greater the opportunity for increasing yields and food security.

ACS811 is a microbial fermentation-based biological product from Alltech …

Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana) woodlands across their range are becoming increasingly threatened by encroaching Douglas-fir encroachment (Pseudotsuga menziesii) as a result of fire exclusion. Using water potential (Ψ), stomatal conductance (g_s), xylem water stable isotopes (dD), and three metrics of biodiversity, this study investigates the effects of conifer encroachment and removal at the ecosystem-scale. The study was set in an Oregon white oak woodland in northern California and compared three levels of encroachment before and after conifer removal. Findings indicate that heavily encroached stands have the least amount of water stress and gas …

Identification And Utilization Of Genetic Determinants Of Trait Measurement Errors In Image-Based, High-Throughput Phenotyping, Yan Zhou, Aaron Kusmec, Seyed Vahid Mirnezami, Lakshmi Attigala, Srikant Srinivasan, Talukder Zaki Jubery, James Schnable, Maria G. Salas Fernandez, Baskar Ganapathysubramanian, Patrick S. Schnable

Department of Agronomy and Horticulture: Faculty Publications

The accuracy of trait measurements greatly affects the quality of genetic analyses. During automated phenotyping, trait measurement errors, i.e., differences between automatically extracted trait values and ground truth, are often treated as random effects that can be controlled by increasing population sizes and/or replication number. By contrast, there is some evidence that trait measurement errors may be partially under genetic control. Consistent with this hypothesis, we observed substantial non-random, genetic contributions to trait measurement errors for five maize (Zea mays) tassel traits collected using an image-based phenotyping platform. The phenotyping accuracy varied according to whether a tassel exhibited …

Environmental Controls On The Terrestrial Water Cycle In Forested Mountain Ecosystems., Luis Andrés Guillén

Graduate Theses, Dissertations, and Problem Reports (ETD)

Water is a key resource to natural ecosystems and human societies alike, and the water cycle is fundamentally linked to the climate and the characteristics of catchments. However, the challenges posed by environmental change makes it imperative to understand how the water cycle is affected by biotic and abiotic factors, in particular, in areas that are crucial sources of water like forested headwater catchments. Therefore, this doctoral dissertation aims to advance the knowledge on the dynamics between climate, vegetation and landscape that determine the water balance of forested mountain ecosystems. This document presents five chapters, an introductory chapter, three standalone …

Genetic Structure Of Pseudoroegneria Spicata In The Northern Palouse Prairie And Channeled Scablands, Ethan Timothy Bean

EWU Masters Thesis Collection

Establishing genetically diverse communities that can adapt to dynamic selective pressures is crucial in ecological restoration. However, the genetic structure of native plant species used for restoration is often poorly understood. Pseudoroegneria spicata, is a keystone species of the Inland Northwestern US that has become a staple in commercially available restoration seed mixes. It is abundant in remnant prairies of the endangered Palouse Prairie ecoregion, which is characterized by rolling hills of deep loess soil. Less than 1% of native Palouse Prairie is left, due to agricultural conversion, with remnants highly fragmented and isolated. P. spicata is also common in …

Wildlife Forage Recovery Following Boreal Wildfire, Alexis Jorgensen, Jennifer Baltzer

Theses and Dissertations (Comprehensive)

Climate change is altering the boreal wildfire regime through increases in the extent and severity of burning and reductions in fire return intervals. These changes can alter the regeneration trajectory of canopy species and ground vegetation, with implications for wildlife habitat. There is some uncertainty about the timelines of when different animal species will use burned areas as their preferred forage taxa recover following fire, and how such recovery is mediated by environmental factors. Here, we aim to address these knowledge gaps through the following questions: 1) What are the main forage types consumed by boreal wildlife and how much …