Botany Commons^™

Photosynthetic Performance And Anti-Oxidative Response Of Cornus Controversa Seedlings Under Cadmium And Lead Stress, Xinyu Huang, Yonglei Jiang, Xiaomao Cheng, Lilan Deng, Xuncheng Liu

Faculty Publications

The photosynthetic efficiency of Cornus controversa leaves was decreased significantly under Cd treatment while it was not affected by Pb exposure. Cd decreased while Pb treatment increased the chlorophyll contents of Cornus controversa leaves. Furthermore, the peroxidase (GPX) activities were decreased after Cd treatment while elevated by Pb exposure in Cornus controvera seedlings. In addition, both Cd and Pb exposures increased the malondialdehyde (MDA) and proline contents and elevated the superoxide dismutase (SOD) activities of Cornus controvera seedlings. Collectively, these results indicated that Cornus controversa may be more tolerant to Pb than Cd toxicity. This finding will contribute to the …

Environmental Data: Soil Moisture, Julia I. Chapman, Eric B. Borth, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Volumetric soil water content measured on May 2, 2015 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Herbaceous 2015, Julia I. Chapman, Margaret E. Maloney, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

Herbaceous vegetation data collected in 2015 at Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Heterologous Expression Of Arabidopsis Thaliana Purple Acid Phosphatase Gene (Atpap15) In Crops For Phytoremediation Of Sites Contaminated With Excess Phosphorus, Jane Jeruto Bartonjo

Masters Theses & Specialist Projects

AtPAP15 is one of the purple acid phosphatases expressed by Arabidopsis thaliana that has been extensively studied. Purified AtPAP15 has been shown to exhibit both phytase and phosphomonoesterase activities in acidic pH with maximal activity at pH 4.5. AtPAP15 is a phosphorus starvation inducible (PSI) gene that is expressed highly during phosphorus deficient conditions. In the current study, AtPAP15 was overexpressed in Nicotiana tabaccum under cauliflower mosaic virus (CaMV35S) constitutive promoter. After PCR confirmation of the gene, plants were transferred to the greenhouse and allowed to grow in pots. The pots contained Sta-Green potting mix (Lowe’s Inc., Mooresville, North Carolina,U.S.). …

Phylogenetic Relationships Of Samydaceae And Taxonomic Revision Of The Species Of Casearia In South-Central Asia, Tharangamala Samarakoon

Dissertations

The flowering plant family Samydaceae was recently reinstated to include 14 genera and about 256 species of tropical trees and shrubs. Preliminary analyses of relationships in the family, however, indicated that the largest genus in the family, Casearia, is not monophyletic and that several smaller groups are probably misplaced. In order to affirm or refute those hypotheses, additional DNA sequence data with broader taxon sampling from the Old World were gathered for phylogenetic analysis. In particular, rapidly evolving plastid (matK, ndhF, psbA-trnH, trnL, and trnL-F) and nuclear (EMB2765 and GBSSI) DNA …

Microsatellite Variations Of Elite Setaria Varieties Released During Last Six Decades In China, Guanqing Jia, Xiaotong Liu, James C. Schnable, Zhengang Niu, Chunfang Wang, Yuhui Li, Shujun Wang, Suying Wang, Jinrong Liu, Erhu Guo, Hui Zhi, Xianmin Diao

Department of Agronomy and Horticulture: Faculty Publications

Crop improvement is a multifaceted micro-evolutionary process, involving changes in breeding approaches, planting configurations and consumption preferences of human beings. Recent research has started to identify the specific genes or genomic regions correlate to improved agronomic traits, however, an apparent blank between the genetic structure of crop elite varieties and their improving histories in diverse modern breeding programs is still in existence. Foxtail millet (Setaria italica) was one of the earliest cereal crops to be domesticated and served as a staple crop for early civilizations in China, where it is still widely grown today. In the present trial, …

A Microhabitat Assessment Of Five Species Of Invasive Plants In The Ozarks And Appalachians, Eric Hearth

Graduate Theses and Dissertations

Invasive species present a threat to native communities and their introduction and expansion can alter community structure and dynamics. Multiple approaches can be employed for invasive species management including prevention and detection. In this study, microhabitat assessments were conducted on colonies of five species of invasive plants, Alliaria petiolata (M. Bieb.) Cavara & Grande, Lespedeza cuneata (Dum. Cours.) G. Don, Lonicera japonica Thunb., Microstegium vimineum (Trin.) A. Camus, and Rosa multiflora Thunb. in the Ozark Plateau and Appalachians. Elevation, soil moisture, soil pH, light ratio, slope, aspect, distance to disturbance, as well as soil nutrient levels were recorded for each …

Molecular Phylogenetics And Historical Biogeography Of The Tribe Chiococceae (Rubiaceae), Sushil Kumar Paudyal

Biological Sciences Theses & Dissertations

Chiococceae are a monophyletic assemblage of morphologically very diverse groups of plants ranging in habit from subshrubs to shrubs to tall trees exhibiting an astonishing variation in shapes and sizes of corolla, and kinds of fruits and seeds. They are primarily distributed in the Neotropics but also occur in the West Pacific islands; thus exhibiting amphi-Pacific tropical disjunction. This study addresses the phylogenetic relationships and biogeography of the Chiococceae using molecular DNA sequence data, and presents novel data on the tribal and generic delimitations, intergeneric relationships, and the origin and dispersal of this group.

In the most recent tribal delimitations …

Upside-Down Anthers Of Clethra Stand Out, W. John Hayden

Biology Faculty Publications

For the most part, the flowers of the 2015 VNPS Wildflower of the Year, Clethra alnifolia (Sweet Pepperbush), are unremarkable. Five separate sepals, 5 sepa rate petals, 10 stamens in 2 whorls, and a 3-carpellate superior ovary—an organization that can only be considered prosaic among the dicots. One floral feature, however, stands out: the anthers in the open flowers are upside-down! (See Figure 1A.) Further, these upside-down anthers open by pores (Figures 1B, 1C) rather than longitudinal slits, as in most flowering plants. These pores initially form on what would normally be the lowermost extremity of the anther, the inversion …

The Linkages Between Photosynthesis, Productivity, Growth And Biomass In Lowland Amazonian Forests, Yadvinder Malhi, Christopher E. Doughty, Gregory R. Goldsmith, Daniel B. Metcalfe, Cécile A.J. Girardin, Toby R. Marthews, Jhon Del Aguila-Pasquel, Luiz E.O.C. Aragão, Alejandro Araujo-Murakami, Paulo Brando, Antonino C.L. Da Costa, Javier E. Silva-Espejo, Filio Farfán Amézquita, David R. Galbraith, Carlos A. Quesada, Wanderley Rocha, Norma Salinas-Revilla, Divino Silvério, Patrick Meir, Oliver L. Phillips

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Amazonian forests spanning gradients in seasonal water deficit and soil fertility. Using the largest data set assembled to date, ten sites in three countries all studied with a standardized methodology, we find that (i) gross primary productivity (GPP) has a simple relationship with seasonal water deficit, but …

Evaluation And Association Mapping Of Resistance To Tan Spot And Stagonospora Nodorum Blotch In Adapted Winter Wheat Germplasm, Zhaohui Liu, Ibrahim El-Basyoni, Gayan Kariyawasam, Guorong Zhang, Allan Fritz, Jana Hansen, Francois Marais, Andrew Friskop, Shiaoman Chao, Eduard Akhunov, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Tan spot and Stagonospora nodorum blotch (SNB), often occurring together, are two economically significant diseases of wheat in the Northern Great Plains of the United States. They are caused by the fungi Pyrenophora tritici-repentis and Parastagonospora nodorum, respectively, both of which produce multiple necrotrophic effectors (NE) to cause disease. In this work, 120 hard red winter wheat (HRWW) cultivars or elite lines, mostly from the United States, were evaluated in the greenhouse for their reactions to the two diseases as well as NE produced by the two pathogens. One P. nodorum isolate (Sn4) and four Pyrenophora tritici-repentis isolates (Pti2, …

Tallgrass Prairie Vegetation Response To Spring Fires And Bison Grazing, Stephen L. Winter, Brady W. Allred, Karen R. Hickman, Samuel D. Fuhlendorf

School of Natural Resources: Faculty Publications

Spring fires in tallgrass prairie can create environmental conditions conducive to plant growth in the subsequent growing season. Following fires, burned areas can also be attractive to grazing animals such as bison (Bison bison). Sustained grazing activity within recently burned areas can alter vegetation structure relative to nearby landscape patches that haven’t burned recently. In 2007, we collected data on bison grazing activity, vegetation structure, and the growth and reproduction of a perennial forb, Arnoglossum plantagineum, in Oklahoma tallgrass prairie. We compared these variables in landscape patches that had burned in the spring of 2007 to measurements …

Flowering Plants: Asteraceae, Part 1, Robert H. Mohlenbrock

Illustrated Flora of Illinois

This, the first of three volumes on the aster family planned for the Illustrated Flora of Illinois series, recognizes 388 species in 119 genera, as well as 20 hybrids and 73 lesser taxa. In Asteraceae, Part 1, author Robert Mohlenbrock presents new and historic information in a clear and easy-to-read style. The volume provides an easy-to-use key to the genera and species and a complete description and nomenclatural and habitat notes for each plant, including its usefulness, if applicable. New nomenclatural combinations are shown for several species. The precise illustrations and detailed information allow for the identification of some …

Evaluating Potential Plant Hormone Cross Talk Between Auxin And Ethylene In Arabidopsis, Mia Lynne Brown

Theses, Dissertations and Capstones

Auxin is the primary hormone responsible for plant growth and development. Regulation of auxin-response genes occurs through transcriptional activators (auxin response factors called ARFs) which bind to auxin response elements (AuxREs). Some auxin-responsive genes encode aminocyclopropane-1-carboxylic acid synthase (ACS) enzymes which regulate the production of the plant hormone ethylene. The major research objective was to evaluate transcriptional cross talk between auxin and ethylene. Both AuxREs and ethylene response elements were found in several ACS and ARF genes, suggesting cross talk between the two hormones at the transcriptional level. Analysis of transgenic Arabidopsis thaliana plants deficient in ARF7 and containing a …

Characterization Of Novel Sorghum Brown Midrib Mutants From An Ems-Mutagenized Population, Scott E. Sattler, Ana Saballos, Zhanguo Xin, Deanna L. Funnell-Harris, Wilfred Vermerris, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Reducing lignin concentration in lignocellulosic biomass can increase forage digestibility for

ruminant livestock and saccharification yields of biomass for bioenergy. In sorghum (Sorghum bicolor (L.) Moench) and several other C4 grasses, brown midrib (bmr) mutants have been shown to reduce lignin concentration. Putative bmr mutants isolated from an EMS-mutagenized population were characterized and classified based on their leaf midrib phenotype and allelism tests with the previously described sorghum bmr mutants bmr2, bmr6, and bmr12. These tests resulted in the identification of additional alleles of bmr2, bmr6, and bmr12, and, in addition, six bmr …

Assessment Of Rice Self-Sufficiency In 2025 In Eight African Countries, P. A.J. Van Oort, K. Saito, E. Amovin-Assagba, Lenny G.J. Van Bussel, Justin Van Wart, Hugo De Groot, Martin K. Van Ittersum, Kenneth Cassman, M. C.S. Wopereis

Department of Agronomy and Horticulture: Faculty Publications

Most African countries are far from self-sufficient in meeting their rice consumption; in eight countries the production: consumption ratio, ranged from 0.16 to 1.18 in 2012. We show that for the year 2025, with population growth, diet change and yield increase on existing land (intensification), countries cannot become fully self-sufficient in rice. This implies that for the future, a mixture of area expansion and imports will be needed on top of yield gap closure. Further research is needed for identification of most suitable new land for rice area expansion and areas that should be protected.

Patch Burning: Implications On Water Erosion And Soil Properties, Altingul Ozaslan Parlak, Mehmet Parlak, Humberto Blanco-Canqui, Walter H. Schacht, John A. Guretzky, Martha Mamo

Department of Agronomy and Horticulture: Faculty Publications

Patch burning can be a potential management tool to create grassland heterogeneity and enhance forage productivity and plant biodiversity, but its impacts on soil and environment have not been widely documented. In summer 2013, we studied the effect of time after patch burning (4 mo after burning [recently burned patches], 16 mo after burning [older burned patches], and unburned patches [control]) on vegetative cover, water erosion, and soil properties on a patch-burn experiment established in 2011 on a Yutan silty clay loam near Mead, NE. The recently burned patches had 29 ± 8.0% (mean ± SD) more bare ground, 21 …

Little Things Reveal The Big Picture, W. John Hayden

Biology Faculty Publications

As enthusiasts who enjoy native plants in natural habitats, we tend to focus on gross morphology— aspects of plant form that can be readily observed with the naked eye or with a hand lens. And there is plenty to see at the gross level. The Flora of Virginia contains 1,269 pages of keys and descriptions devoted to gross morphology of the commonwealth’s botanical treasures. Morphological diversity, however, does not stop at the magnifi cation limit of a hand lens. Light and electron microscopes open up whole new worlds of intricate structure for appreciation and study. And tiny structural details can …

Plant Functional Traits Of Dominant Native And Invasive Species In Mediterranean-Climate Ecosystems, Jennifer L. Funk, Rachel J. Standish, William D. Stock, Fernando Valladares

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The idea that dominant invasive plant species outperform neighboring native species through higher rates of carbon assimilation and growth is supported by several analyses of global datasets. However, theory suggests that native and invasive species occurring in low-resource environments will be functionally similar, as environmental factors restrict the range of observed physiological and morphological trait values. We measured resource-use traits in native and invasive plant species across eight diverse vegetation communities distributed throughout the five Mediterranean-climate regions, which are drought-prone and increasingly threatened by human activities including the introduction of exotic species. Traits differed strongly across the five regions. In …

Transgenic Wheat Expressing A Barley Udp-Glucosyltransferase Detoxifies Deoxynivalenol And Provides High Levels Of Resistance To Fusarium Graminearum, Xi Li, Sanghyun Shin, Shane Heinen, Ruth Dill-Macky, Franz Berthiller, Natalya Nersesian, Thomas Clemente, Susan Mccormick, Gary J. Muehbauer

Department of Agronomy and Horticulture: Faculty Publications

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, is a devastating disease of wheat that results in economic losses worldwide. During infection, F. graminearum produces trichothecene mycotoxins, including deoxynivalenol (DON), that increase fungal virulence and reduce grain quality. Transgenic wheat expressing a barley UDP-glucosyltransferase (HvUGT13248) were developed and evaluated for FHB resistance, DON accumulation, and the ability to metabolize DON to the less toxic DON-3-O-glucoside (D3G). Pointinoculation tests in the greenhouse showed that transgenic wheat carrying HvUGT13248 exhibited significantly higher resistance to disease spread in the spike (type II resistance) compared with nontransformed controls. Two transgenic …

Fall Seed Guide 2015, Teshome Regassa, P. Stephen Baenziger, Stephen N. Wegulo, Greg Kruger, Dipak K. Santra

Department of Agronomy and Horticulture: Faculty Publications

Crops included in this guide are winter wheat, winter barley, and triticale. You may receive this guide in the mail or through the University of Nebraska Extension network. The data and other information this guide is can be found at our web site: http://cropwatch.unl.edu/varietytest/ and http://www.unl.edu/ncia. Additional information is available at the wheat variety virtual tour web site http://cropwatch.unl.edu/wheat/virtual or the winter wheat variety selection tool page http:// citnews.unl.edu/winter_wheat_tool/index.shtml. The last season was hard on Nebraska winter wheat. Emergence was poor in the west due to dry conditions. On the other hand, some plots in the east had to be …

Model And Sensor-Based Recommendation Approaches For In-Season Nitrogen Management In Corn, L. J. Thompson, R. B. Ferguson, N. Kitchen, D. W. Frazen, M. Mamo, H. Yang, J. S. Schepers

Department of Agronomy and Horticulture: Faculty Publications

Nitrogen management for corn (Zea mays L.) may be improved by applying a portion of N in-season. This investigation was conducted to evaluate crop modeling (Maize-N) and active crop canopy sensing approaches for recommending in-season N fertilizer rates. These approaches were evaluated during 2012–2013 on 11 field sites, in Missouri, Nebraska, and North Dakota. Nitrogen management also included a no-N treatment (check) and a non-limiting N reference (all at planting). Nitrogen management treatments were assessed for two hybrids and at low and high seeding rates, arranged in a randomized complete block design. In 9 of 11 site-years, the sensor-based …

Native Orchids In Winter?, W. John Hayden

Biology Faculty Publications

A very special place in Southwest Virginia will soon expand its borders, thanks in part to the annual fundraising appeal by the Virginia Native Plant Society. The Cedars Natural Area Preserve supports ex ceptional natural communities including rocky, dry limestone glades and woodlands located across nearly 20 square miles in Lee County near the Powell River. The karst landscape, where thin soils develop over easily dissolved limestone bedrock, creates terrain that tends to be rolling, rocky, rugged, and full of sinkholes, caves, and sinking streams. The preserve is a haven for rare plants that have adapted to the mostly thin, …

Physiological Variation Of Garry Oak (Quercus Garryana) Seedlings To Drought Stress, Matthew A. Merz

All Master's Theses

The purpose of this study was to determine physiological differences in drought response among Garry oak (Quercus garryana Douglas ex Hook. [Fagaceae]) seedlings that grow in distinct populations in Washington state, in order to aid in restoration efforts by informing growers of the potential differences between the acorn collection sites. Acorns from six Washington populations east of the Cascades, as well as one population from Whidbey Island, were collected and grown in containers under controlled conditions. The plants were assessed with and without moderate and severe drought stress induced by withholding water. The most extreme differences in photosynthetic characteristics …

Potential For Crop Production Increase In Argentina Through Closure Of Existing Yield Gaps, Fernando Aramburu Merlos, Juan Pablo Monzon, Jorge L. Mercau, Miguel Taboada, Fernando H. Andrade, Antonio J. Hall, Esteban Jobbagy, Kenneth Cassman, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Favorable climate and soils for rainfed crop production, together with a relatively low population density,results in 70–90% of Argentina grain production being exported. No assessment to date has tried to estimate the potential for extra grain production for soybean, wheat and maize, which account for 78%of total harvested area, by yield gap closure on existing cropland area and its impact at a global scale.The objectives of this paper are (i) to estimate how much additional grain could be produced without expanding crop area by closing yield gaps in Argentina, (ii) to investigate how this production and yield gaps varies across …

Plants Coping Abiotic And Biotic Stresses: A Tale Of Diligent Management, Hatem Rouached, Sikander Pal, Shimon Rachmilevitch, Marc Libault, Lam-Son Phan Tran

Department of Agronomy and Horticulture: Faculty Publications

Plants unlike other living forms are sessile thereby facing severe biotic and abiotic stresses. Plants have evolved different efficient defence responses which thrive upon a number of intrinsic factors, such as genotypic and phenotypic constitutions and developmental circumstances, and extrinsic factors like severity and duration of the stresses. Stress management uses molecular and biochemical level controls, the competence, and speed, at which a stress signal is perceived and transmitted to generate stress signal molecules and activate stress-protective mechanisms. A well-concerted action of the plants’ competence at morphological, physiological, biochemical, and molecular strata regulates numerous adaptive responses to biotic and abiotic …

Calibration And Validation Of The Hybrid-Maize Crop Model For Regional Analysis And Application Over The U.S. Corn Belt, Xing Liu, Jeff Andresen, Haishun Yang, Dev Niyogi

Department of Agronomy and Horticulture: Faculty Publications

Detailed parameter sensitivity, model validation, and regional calibration of the Hybrid-Maize crop model were undertaken for the purpose of regional agroclimatic assessments. The model was run at both field scale and county scale. The county-scale study was based on 30-yr daily weather data and corn yield data from the National Agricultural Statistics Service survey for 24 locations across the Corn Belt of the United States. The field-scale study was based on AmeriFlux sites at Bondville, Illinois, andMead, Nebraska. By using the one-at-a-time and interaction-explicit factorial design approaches for sensitivity analysis, the study found that the five most sensitive parameters of …

Do Epidermal Cell Types Have An Effect Upon Ultraviolet Patterns On Flower Petals?, Margaux Flaherty

Williams Honors College, Honors Research Projects

Flower petal epidermal cell shape and ultraviolet patterns called nectar guides may have a considerable impact on pollinator behavior and consequently, the reproductive success of the floral species. Similarly, flower petal epidermal cell shape may have an effect on floral color; however, these effects have only been measured in the visible light range (Whitney et al., 2009). This study attempts to determine if epidermal cell shape has an effect upon ultraviolet floral patterns. Experimental results show that all of the floral species studied seem to have a conical epidermal cell shape, but varying levels of ultraviolet reflectance and absorbance; …

Identification Of Novel Qtl Governing Root Architectural Traits In An Interspecific Soybean Population, Lakshmi P. Manavalan, Silvas J. Prince, Theresa A. Musket, Julian Chaky, Rupesh Deshmukh, Tri D. Vuong, Li Song, Perry B. Cregan, James C. Nelson, J. Grover Shannon, James E. Specht, Henry T. Nguyen

Department of Agronomy and Horticulture: Faculty Publications

Cultivated soybean (Glycine max L.) cv. Dunbar (PI 552538) and wild G. soja (PI 326582A) exhibited significant differences in root architecture and root-related traits. In this study, phenotypic variability for root traits among 251 BC₂F₅ backcross inbred lines (BILs) developed from the cross Dunbar/PI 326582A were identified. The root systems of the parents and BILs were evaluated in controlled environmental conditions using a cone system at seedling stage. The G. max parent Dunbar contributed phenotypically favorable alleles at a major quantitative trait locus on chromosome 8 (Satt315-I locus) that governed root traits (tap root length and …

Genetic And Molecular Characterization Of Submergence Response Identifies Subtol6 As A Major Submergence Tolerance Locus In Maize, Malachy T. Campbell, Christopher A. Proctor, Yongchao Dou, Aaron J. Schmitz, Piyaporn Phansak, Greg R. Kruger, Chi Zhang, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Maize is highly sensitive to short term flooding and submergence. Early season flooding reduces germination, survival and growth rate of maize seedlings. We aimed to discover genetic variation for submergence tolerance in maize and elucidate the genetic basis of submergence tolerance through transcriptional profiling and linkage analysis of contrasting genotypes. A diverse set of maize nested association mapping (NAM) founder lines were screened, and two highly tolerant (Mo18Wand M162W) and sensitive (B97 and B73) genotypes were identified. Tolerant lines exhibited delayed senescence and lower oxidative stress levels compared to sensitive lines. Transcriptome analysis was performed on these inbreds to provide …