Plant Biology Commons^™

A Study Of The Historical Development And Horticultural Practices Of A Public Garden, Steven J. Nosal

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

This project examined the historical development and the horticultural practices in the public gardens of the Parks Department in Lincoln, Neb. It concentrates on one particular place to illustrate development and practice issues: the Sunken Gardens. This garden was built during the Depression in the 1930s as a place of beauty for all of the citizens of Lincoln. Although the Sunken Garden covers only 1.5 acres, it has remained a very important part of Nebraska's capital city for more than 64 years.

Study Of Thermotolerance Mechanism In Gossypium Hirsutum Through Identification Of Heat Stress Genes, Jin Zhang

Graduate Theses and Dissertations

ABSTRACT

Heat stress causes major losses to cotton seed and lint yield. Introduction of heat stress tolerance to Arkansas cotton varieties is highly desirable. However, very little is known about the molecular basis of heat stress tolerance in cotton. The present study attempted to identify heat stress tolerance genes in two heat-tolerant cotton cultivars, VH260 and MNH456, originating from Pakistan. Towards this, the expression profile of the cotton orthologs of sevenArabidopsisheat stress tolerance genes was studied in these two cultivars, and compared with the two heat-susceptible cotton cultivars, ST213 and ST4288, originating from Mississippi Delta region. In addition, physiological parameters …

Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Conserved non-coding sequences (CNS) are islands of non-coding sequence that, like protein coding exons, show less divergence in sequence between related species than functionless DNA. Several CNSs have been demonstrated experimentally to function as cis-regulatory regions. However, the specific functions of most CNSs remain unknown. Previous searches for CNS in plants have either anchored on exons and only identified nearby sequences or required years of painstaking manual annotation. Here we present an open source tool that can accurately identify CNSs between any two related species with sequenced genomes, including both those immediately adjacent to exons and distal sequences separated by …

Rate Of Shattercane × Sorghum Hybridization In Situ, Jared J. Schmidt, Jeffrey F. Pedersen, Mark L. Bernards, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Cultivated sorghum [Sorghum bicolor (L.) Moench subsp. bicolor] can interbreed with a feral weedy relative shattercane [S. bicolor nothosubsp. drummondii (Steud.) de Wet ex Davidse]. Traits introduced from cultivated sorghum could contribute to the invasiveness of a shattercane population. An experiment was conducted to determine the potential for pollenmediated gene flow from grain sorghum to shattercane. Shattercane with juicy midrib (dd) was planted in soybean [Glycine max (L.) Merr.] fields during 2 yr in concentric arcs at varying distances from a 0.39 ha sorghum pollen source with dry midrib (DD). The arcs …

Herbaceous 2013, Julia I. Chapman, Amy L. Myers, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Herbaceous vegetation data collected in 2013 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Survey Of Suitable Plants For Cal Poly's Green Wall, Katrina Burritt

Horticulture and Crop Science

Green wall technology is a growing industry in the United States and has been very successful for a several years throughout Europe. The objective of this survey was to study the success of several different species of plants on a vertical wall facing south at Cal Poly’s Horticultural Department Unit. At first the focus was aimed at using California native species, because it was thought that natives would be better acclimated to the exposure in this specific location. It became apparent that plants should not be selected for the wall based just on the fact that they are California natives. …

Evaluating The Success Of Seed Sowing In A New England Grassland, Chad C. Jones, Glenn D. Dreyer, Nels Barrett

Botany Faculty Publications

Grassland habitat is declining in the northeastern United States, leading to a decline in associated native species. Consequently, there is considerable interest by land managers in conserving and restoring grassland habitats in the Northeast. However, unlike the Great Plains and Europe, quantitative monitoring of restoration sites is uncommon, making it difficult to improve new restoration projects. Here we evaluate a grassland restoration in Waterford, Connecticut to determine if mechanical clearing of woody vegetation combined with sowing 23 native grasses and forbs led to successful establishment of these species. We also compared cover, diversity, and colonization by exotic and woody species …

2013 Virginia Wildflower Of The Year: Redbud, Cercis Canadensis, W. John Hayden

Biology Faculty Publications

Redbuds are small trees or shrubs that may attain heights of 10 m or so. Leaves are alternate and two-ranked, simple, entire, deciduous, broadly cordate, with an acute apex, 611 cm long, 712 cm wide, and palmately veined. Petioles have two swollen pulvini, one at its connection with the stem, the other at its junction with the leaf blade.

Sub1a-Mediated Submergence Tolerance Response In Rice Involves Differential Regulation Of The Brassinosteroid Pathway, Aaron J. Schmitz, Jing J. Folsom, Yusuke Jikamaru, Pamela C. Ronald, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Submergence 1A (SUB1A), is an ethylene response factor (ERF) that confers submergence tolerance in rice (Oryza sativa) via limiting shoot elongation during the inundation period. SUB1A has been proposed to restrict shoot growth by modulating gibberellic acid (GA) signaling.

Our transcriptome analysis indicated that SUB1A differentially regulates genes associated with brassinosteroid (BR) synthesis during submergence. Consistent with the gene expression data, the SUB1A genotype had higher brassinosteroid levels after submergence compared to the intolerant genotype. Tolerance to submergence can be activated in the intolerant genotype by pretreatment with exogenous brassinolide, which results in restricted shoot elongation …

Morphology, Structure, Function And Evolution Of Infrastaminal Scales In Cuscuta (Convolvulaceae), Stephanie Riviere

Theses and Dissertations (Comprehensive)

Cuscuta (dodder, Convolvulaceae) is a genus of about 200 species of obligate stem parasites of cosmopolitan distribution. Infrastaminal scales (IFS) are staminode-like formations that surround the ovary in the flowers of dodders. Their morphological diversity has historically provided some of the most useful taxonomic diagnostic characters at the species-level, however, their function had not been determined. I performed a comparative study of the IFS in 147 taxa using light, scanning and transmission electron microscopy, and results were analyzed in relation to a Cuscuta phylogeny obtained from a combined analysis of rbcL and 26S rDNA gene sequences. To test the hypothesis …

Factors Influencing The Establishment And Survival Of Native Hardwood Tree Seedlings Of The Kentucky Inner Bluegrass Blue Ash-Oak Savanna-Woodland, James D. Shaffer

Theses and Dissertations--Biology

Historically, the Kentucky Inner Bluegrass blue ash-oak savanna-woodland was the primary ecosystem of the Inner Bluegrass Region (IBR) of Kentucky. After European settlement, the majority (>99%) of Bluegrass savanna was converted to agricultural and urban land uses. Currently remnant savanna tree species are failing to recruit. Therefore, a long-term restoration ecology project researching competition and disturbance on seedling establishment, survival, and growth has been established at Griffith Woods (the largest remaining savanna in Kentucky) in Harrison Co., KY. Fourteen native hardwood tree species (a total of 6,168 seedlings) have been experimentally planted. Light, soil, surrounding vegetation, and herbivory, factors …

Immunodetection Of Triticum Mosaic Virus By Das- And Dac-Elisa Using Antibodies Produced Against Coat Protein Expressed In Escherichia Coli: Potential For High-Throughput Diagnostic Methods, Satyanarayana Tatineni, Gautam Sarath, Dallas Seifers, Roy C. French

Department of Agronomy and Horticulture: Faculty Publications

Triticum mosaic virus (TriMV), an economically important virus infecting wheat in the Great Plains region of the USA, is the type species of the Poacevirus genus in the family Potyviridae. Sensitive and high-throughput serology-based detection methods are crucial for the management of TriMV and germplasm screening in wheat breeding programs. In this study, TriMV coat protein (CP) was expressed in Escherichia coli, and polyclonal antibodies were generated against purified soluble native form recombinant CP (rCP) in rabbits. Specificity and sensitivity of resulting antibodies were tested in Western immuno-blot and enzyme-linked immunosorbent assays (ELISA). In direct antigen coating (DAC)-ELISA, …

Soil Sorptivity Enhancement With Crop Residue Accumulation In Semiarid Dryland No-Till Agroecosystems, T.M. Shaver, G. A. Peterson, Laj R. Ahuja, D.G. Westfall

Department of Agronomy and Horticulture: Faculty Publications

Water capture and precipitation use efficiency are of great importance in dryland cropping systems because the world's dependence on food produced in dryland areas continues to increase. Growing season evapotranspiration potential greatly exceeds growing season precipitation rates in dryland areas, creating a water deficit for crops. Management practices that positively impact soil physical properties increase the potential for soils to capture water. One way to assess the ability of soils to capture water is through the measurement of sorptivity. Sorptivity is defined as the cumulative infiltration proportionality constant and is governed by surface soil physical properties such as texture, degree …

Influence Of Two Herbicides On Soybean Cyst Nematode (Heterodera Glycines) Reproduction On Henbit (Lamium Amplexicaule) Roots, Rodrigo Werle, Mark L. Bernards, Loren J. Giesler, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Soybean cyst nematode (SCN) is the most yield-limiting pathogen of soybean in the United States. Henbit is a prevalent winter annual weed species in no-till fields and is reported to be an alternative host of SCN. A greenhouse study was conducted to evaluate how the development of SCN on henbit roots was affected by herbicide mode of action and time of herbicide application. Henbit plants were grown in watertight pots placed in a water bath bench that kept soil temperature constant (27 6 1 C) during the study. Ten d after transplanting, pots were inoculated with approximately 1,000 SCN eggs. …

Redbud Cauliflory: The Inside Story, W. John Hayden

Biology Faculty Publications

One of the most distinctive features of redbuds, Cercis canadensis, the 2013 VNPS Wildflower of the Year, is its production of flowers on mature trunks and major branches, a habit termed cauliflory. Redbud flowers also form on young, one-year old twigs; as explained below, twig- and trunk-borne flowers are parts of a single developmental continuum; twigs bearing flowers eventually becoming trunks and large branches that continue to bear flowers.

Genetic Mapping And Confirmation Of Quantitative Trait Loci For Seed Protein And Oil Contents And Seed Weight In Soybean, Safiullah M. Pathan, Tri Vuong, Kerry Clark, Jeong-Dong Lee, J. Grover Shannon, Craig A. Roberts, Mark R. Ellersieck, Joseph W. Burton, P. B. Cregan, David L. Hyten, Henry T. Nguyen, David A. Sleper

Department of Agronomy and Horticulture: Faculty Publications

Demand for soybean [Glycine max (L.) Merr.] meal has increased worldwide and soybean importers often offer premiums for soybean containing higher contents of protein and oil. Objectives were to detect quantitative trait loci (QTL) associated with soybean seed protein, oil, and seed weight in a soybean mapping population and confirm detected QTL across genetic backgrounds and environments. Two populations of 216 and 156 recombinant inbred lines were developed from Magellan × PI 438489B and Magellan × PI 567516C crosses, respectively, and grown in two Missouri environments in 2008. More than 900 simple sequence repeat (SSR) and single nucleotide polymorphism …

Development And Evaluation Of Soysnp50k, A High-Density Genotyping Array For Soybean, Qijian Song, D. L. Hyten, Gaofeng Jia, Charles V. Quigley, Edward W. Fickus, Randall L. Nelson, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

The objective of this research was to identify single nucleotide polymorphisms (SNPs) and to develop an Illumina Infinium BeadChip that contained over 50,000 SNPs from soybean (Glycine max L. Merr.). A total of 498,921,777 reads 35–45 bp in length were obtained from DNA sequence analysis of reduced representation libraries from several soybean accessions which included six cultivated and two wild soybean (G. soja Sieb. et Zucc.) genotypes. These reads were mapped to the soybean whole genome sequence and 209,903 SNPs were identified. After applying several filters, a total of 146,161 of the 209,903 SNPs were determined to be …

Mapping Soybean Aphid Resistance Genes In Pi 567598b, Carmille Bales, Guorong Zhang, Menghan Liu, Clarice Mensah, Cuihua Gu, Qijian Song, D. L. Hyten, P. B. Cregan, Dechun Wang

Department of Agronomy and Horticulture: Faculty Publications

The soybean aphid (Aphis glycines Matsumura) has been a major pest of soybean [Glycine max (L.) Merr.] in North America since it was first reported in 2000. Our previous study revealed that the strong aphid resistance of plant introduction (PI) 567598B was controlled by two recessive genes. The objective of this study was to locate these two genes on the soybean genetic linkage map using molecular markers. A mapping population of 282 F_4:5 lines derived from IA2070 X E06902 was evaluated for aphid resistance in a field trial in 2009 and a greenhouse trial in 2010. Two …

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Antioch University Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered …

Yield Gap Analysis—Rationale, Methods And Applications—Introduction To The Special Issue, M.K. Van Ittersum, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

Yield gap analysis is an increasingly popular concept. It is a powerful method to reveal and understand the biophysical opportunities to meet the projected increase in demand for agricultural products towards 2050, and to support decision making on research, policies, development and investment that is needed. This Special Issue presents the state-of-the-art about concepts, methods and applications of yield gap analysis. The methodological papers emphasize the need for agronomically sound and relevant analyses, from local to global scales. The fourteen papers provide examples of applications to different crops, climate zones and production conditions, at various spatial extents and with different …

Distinguishing Between Yield Advances And Yield Plateaus In Historical Crop Production Trends, Patricio Grassini, Kent M. Eskridge, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

Food security and land required for food production largely depend on rate of yield gain of major cereal crops. Previous projections of food security are often more optimistic than what historical yield trends would support. Many econometric projections of future food production assume compound rates of yield gain, which are not consistent with historical yield trends. Here we provide a framework to characterize past yield trends and show that linear trajectories adequately describe past yield trends, which means the relative rate of gain decreases over time. Furthermore, there is evidence of yield plateaus or abrupt decreases in rate of yield …

Agricultural Innovation To Protect The Environment, Jeffrey Sayer, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

In a world of 9.5 billion people, global demand for food, fiber, and biofuels has to be met with minimal possible increases in land, water, fossil fuels, and the minerals used to produce fertilizers (1–4). The problem is debated at three levels: first, that agriculture will not be able to produce enough because it will come up against both biophysical and environmental limits that restrict yields (3, 5, 6); second, that the need to expand and intensify agriculture will destroy the broader environmental values of forests, wetlands, marine systems, and their associated biodiversity (7–9); and third, that there are institutional …

New Technologies Reduce Greenhouse Gas Emissions From Nitrogenous Fertilizer In China, Wei-Feng Feng, Zheng-Xia Dou, Pan He, Xiao-Tang Ju, David Powlson, Dave Chadwick, David Norse, Yue-Lai Lu, Ying Zhang, Liang Wu, Xin-Ping Chen, Kenneth Cassman, Fu-Suo Zhang

Department of Agronomy and Horticulture: Faculty Publications

Synthetic nitrogen (N) fertilizer has played a key role in enhancing food production and keeping half of the world’s population adequately fed. However, decades of N fertilizer overuse in many parts of the world have contributed to soil, water, and air pollution; reducing excessive N losses and emissions is a central environmental challenge in the 21st century. China’s participation is essential to global efforts in reducing N-related greenhouse gas (GHG) emissions because China is the largest producer and consumer of fertilizer N. To evaluate the impact of China’s use of N fertilizer, we quantify the carbon footprint of China’s N …

The Clubroot Pathogen (Plasmodiophora Brassicae) Influences Auxin Signaling To Regulate Auxin Homeostasis In Arabidopsis, Linda Jahn, Stefanie Mucha, Sabine Bergmann, Cornelia Horn, Paul E. Staswick, Bianka Steffens, Johannes Siemens, Jutta Ludwig-Müller

Department of Agronomy and Horticulture: Faculty Publications

The clubroot disease, caused by the obligate biotrophic protist Plasmodiophora brassicae, affects cruciferous crops worldwide. It is characterized by root swellings as symptoms, which are dependent on the alteration of auxin and cytokinin metabolism. Here, we describe that two different classes of auxin receptors, the TIR family and the auxin binding protein 1 (ABP1) in Arabidopsis thaliana are transcriptionally upregulated upon gall formation. Mutations in the TIR family resulted in more susceptible reactions to the root pathogen. As target genes for the different pathways we have investigated the transcriptional regulation of selected transcriptional repressors (Aux/IAA) and transcription …

Maternal Environment Effects On Phenolic Defenses In Abutilon Theophrasti Seeds, Brian J. Schutte, Sam E. Wortman, John L. Lindquist, Adam S. Davis

Department of Agronomy and Horticulture: Faculty Publications

A class of phenolic compounds, ortho-dihydroxyphenols (hereafter “o-DHP”), has been implicated with seed survival. Based on expectations of the growth-differentiation balance hypothesis, we predicted that seed o-DHP concentration exhibits a curvilinear response to increasing resource availability in the maternal environment, with maximum o-DHP occurring at moderate resource levels. To test this hypothesis, Abutilon theophrasti seeds were produced under field conditions at two locations. Each location included twelve maternal environments established through factorial combinations of soil compost (+/−), species assemblage (A. theophrasti with and without maize), and soil nitrogen fertilizer (0, 0.5× or 1× local …

Dna Fingerprinting And Anastomosis Grouping Reveal Similar Genetic Diversity In Rhizoctonia Species Infecting Turfgrasses In The Transition Zone Of Usa, B. S. Amaradasa, B. J. Horvath, D. K. Lakshman, S. E. Warnke

Department of Agronomy and Horticulture: Faculty Publications

Rhizoctonia blight is a common and serious disease of many turfgrass species. The most widespread causal agent, Thanatephorus cucumeris (anamorph: R. solani), consists of several genetically different subpopulations. In addition, Waitea circinata varieties zeae, oryzae and circinata (anamorph: Rhizoctonia spp.) also can cause the disease. Accurate identification of the causal pathogen is important for effective management of the disease. It is challenging to distinguish the specific causal pathogen based on disease symptoms or macroscopic and microscopic morphology. Traditional methods such as anastomosis reactions with tester isolates are time consuming and sometimes difficult to interpret. In the present study universally …

The Plant Science Decadal Vision: Response To The Martin Commentary, David Stern, Sally Ann Mackenzie

Department of Agronomy and Horticulture: Faculty Publications

The plant science community is being called upon as never before to carry out research that addresses challenges in food, climate, and health, to educate a populace inundated with science misinformation, and to excite and recruit a new generation of scientists from among that populace, all while investments in basic research are stagnant or even declining in many countries. The Decadal Vision (Plant Science Research Summit, 2013) represents a response from that community, one that launches a meaningful and ongoing dialogue about how best to accomplish these goals. In that spirit, we welcome this thoughtful commentary by Cathie Martin (Martin, …

Chloroplast Division Protein Arc3 Regulates Chloroplast Ftsz-Ring Assembly And Positioning In Arabidopsis Through Interaction With Ftsz2, Min Zhang, Aaron J. Schmitz, Deena K. Kadirjan-Kalbach, Allan D. Terbush, Katherine W. Osteryoung

Department of Agronomy and Horticulture: Faculty Publications

Chloroplast division is initiated by assembly of a mid-chloroplast FtsZ (Z) ring comprising two cytoskeletal proteins, FtsZ1 and FtsZ2. The division-site regulators ACCUMULATION AND REPLICATION OF CHLOROPLASTS3 (ARC3), MinD1, and MinE1 restrict division to the mid-plastid, but their roles are poorly understood. Using genetic analyses in Arabidopsis thaliana, we show that ARC3 mediates division-site placement by inhibiting Z-ring assembly, and MinD1 and MinE1 function through ARC3. ftsZ1 null mutants exhibited some mid-plastid FtsZ2 rings and constrictions, whereas neither constrictions nor FtsZ1 rings were observed in mutants lacking FtsZ2, suggesting FtsZ2 is the primary determinant of Z-ring assembly in vivo. arc3 …

Resource Allocation For Maximizing Prediction Accuracy And Genetic Gain Of Genomic Selection In Plant Breeding: A Simulation Experiment, Aaron Lorenz

Department of Agronomy and Horticulture: Faculty Publications

Allocating resources between population size and replication affects both genetic gain through phenotypic selection and quantitative trait loci detection power and effect estimation accuracy for marker-assisted selection (MAS). It is well known that because alleles are replicated across individuals in quantitative trait loci mapping and MAS, more resources should be allocated to increasing population size compared with phenotypic selection. Genomic selection is a form of MAS using all marker information simultaneously to predict individual genetic values for complex traits and has widely been found superior to MAS. No studies have explicitly investigated how resource allocation decisions affect success of genomic …

Evaluation Of Public Sweet Sorghum A-Lines For Use In Hybrid Production, Jeffrey F. Pedersen, Scott E. Sattler, William F. Anderson

Department of Agronomy and Horticulture: Faculty Publications

A fundamental need for commercialization of sweet sorghum [Sorghum bicolor (L.) Moench] as a bioenergy crop is an adequate seed supply, which will require development of hybrid varieties using dwarf seed-parent lines. A set of six public sweet sorghum A-lines (Dwarf Kansas Sourless, KS9, N36, N38, N39, and N4692) were crossed with a set of six public sweet sorghum cultivars (Brawley, Kansas Collier, Dale, Sugar Drip, Waconia, and Wray). Grain, fiber, and sugar yields were determined, and conversion formulas were applied to estimate ethanol yields. Hybrids were grown in fields at Ithaca, NE, USA, in 1983– 1984 fertilized with …