Botany Commons^™

Induced Systemic Resistance Against Nematodes By Plant Growth-Promoting Microbes In Potatoes, Cole Grannan

Master's Theses

Biofertilizers consist of plant growth-promoting microorganisms that establish symbiotic relationships with plant roots and stems. These beneficial microbes play a crucial role in enhancing plant defenses against various threats including insects, nematodes, and microbial pathogens. The purpose of this study was to investigate the effectiveness of two fungal biofertilizers (an endophytic strain of Beauveria bassiana (BA) and a mixture of arbuscular mycorrhizal (AM) fungi), specifically their ability to induce systemic resistance against plant- parasitic nematodes (PPNs) in potatoes (Solanum tuberosum cv. Masquerade) under controlled greenhouse conditions. The study utilized soil collected from Colorado State University’s San Luis Valley (SLV) Research …

Evaluating The Duckweeds Lemna Minor And Spirodela Polyrhiza As Alternative Aquatic Hosts For The Spread Of The Bacterial Wilt Pathogen, Ralstonia Solanacearum, Irelynn Smith

Honors Theses

Ralstonia solanacearum is a plant pathogen that causes bacterial wilt disease in major crops such as tomatoes and potatoes. Recently, this bacterium was discovered in floating pennywort (Hydrocotyle ranunculoides) and Pennsylvania smartweed (Polygonum pennysylvanicum), two previously unsuspected aquatic plants. Duckweed is an aquatic plant with a high level of resilience and short doubling time. Common duckweed (Lemna minor) has previously demonstrated its capability as a versatile high-yield infection model for other types of pathogenic bacteria. Given this newfound branch of aquatic hosts and the fact that duckweed is a common pond weed previously identified in several ponds located nearby infected …

Elevation And Population Size Effects On The Survival Of Drosera Rotundifolia, Jessica Williams

Electronic Theses and Dissertations

Carnivorous plants face significant conservation challenges due to habitat destruction, climate change, and illegal harvesting. This study explores how elevation and population size influence key-life history traits of D. rotundifolia, such as flowering phenology, prey capture efficiency, seed production, and germination rates. Higher elevations and larger populations are associated with extended flowering durations and increased prey capture. However, seed production and germination rates show complex patterns that are likely influenced by genetic diversity, resource availability, or environmental conditions. These insights inform targeted conservation strategies, emphasizing habitat preservation, enhancing prey availability, and maintaining genetic diversity. Public education and community engagement …

Broad-Spectrum Resistance To Fungal Foliar Diseases In Wheat: Recent Efforts And Achievements, Amira M.I. Mourad, Asmaa A.M. Ahmed, P. Stephen Baenziger, Andreas Börner, Ahmed Sallam

Department of Agronomy and Horticulture: Faculty Publications

Wheat (Triticum spp.) is one of the most important cereal crops in the world. Several diseases affect wheat production and can cause 20-80% yield loss annually. Out of these diseases, stripe rust, also known as yellow rust (Puccinia striiformis f. sp. tritici), stem rust (Puccinia graminis f. sp. tritici), leaf rust (Puccinia recondita), and powdery mildew (Blumeria graminis f. sp. tritici) are the most important fungal diseases that infect the foliar part of the plant. Many efforts were made to improve wheat resistance to these diseases. Due to the continuous advancement in …

Disentangling Genotype And Environment Specific Latent Features For Improved Trait Prediction Using A Compositional Autoencoder, Anirudha Powadi, Talukder Zaki Jubery, Michael C. Tross, James C. Schnable, Baskar Ganapathysubramanian

Department of Agronomy and Horticulture: Faculty Publications

In plant breeding and genetics, predictive models traditionally rely on compact representations of high-dimensional data, often using methods like Principal Component Analysis (PCA) and, more recently, Autoencoders (AE). However, these methods do not separate genotype-specific and environment-specific features, limiting their ability to accurately predict traits influenced by both genetic and environmental factors. We hypothesize that disentangling these representations into genotype-specific and environment-specific components can enhance predictive models. To test this, we developed a compositional autoencoder (CAE) that decomposes high-dimensional data into distinct genotype-specific and environment-specific latent features. Our CAE framework employed a hierarchical architecture within an autoencoder to effectively separate …

Industrial Hemp Biomass Negatively Affected By Herbicide Drift From Corn And Soybean Herbicides, Milos Zaric, Bruno Canella Vieira, Barbara Houston, Guilherme Sousa Alves, Samuel E. Wortman, Julie A. Peterson, Greg R. Kruger

Department of Agronomy and Horticulture: Faculty Publications

The establishment of industrial hemp (Cannabis sativa L.) fields near row crops has raised concerns about the potential adverse effects of herbicide drift on hemp production. This study examined hemp susceptibility to drift of herbicides registered for use in corn and/or soybeans. Herbicide solutions (2,4-D, dicamba, glufosinate, glyphosate, imazethapyr, lactofen, mesotrione) were applied separately in the wind tunnel (3.6 m s⁻¹ airspeed), simulating drift scenarios, with conventional TP95015EVS (TP) and air inclusion AI95015EVS (AI) flat fan nozzles calibrated to deliver 140 L ha⁻¹ carrier volume at 230 kPa. Mylar cards and hemp plants (20–25 cm tall) were placed …

A Multidirectional Study On Chemical Fingerprints And Biological Activities Of Three Cistus Extracts (C. Creticus, C. Laurifolius, And C. Salviifolius) With Ethnomedicinal Uses, Sakina Yagi, Gökhan Zengi̇n, Selami̇ Selvi̇, Güneş Ak, Zoltán Cziáky, József Jekő, Maria J. Rodrigues, Luisa Custodio, Roberto Venanzoni, Giancarlo Angeles Flores, Gaia Cusumano, Paola Angelini

Turkish Journal of Botany

Humans have used medicinal plants to treat various diseases for thousands of years. Cistus species are also widely used in traditional medicine and have various medicinal applications; therefore, they deserve more in-depth research. The present study evaluated the chemical profile, antioxidant, enzyme inhibition, and cytotoxic properties of the twigs and leaves of C. creticus L., C. laurifolius L., and C. salviifolius L. grown in Türkiye. Methanolic extracts of the three species were rich in phenolics, mainly flavonoids, and exerted potent antioxidant activity with methanolic extract from the leaves of C. salviifolius displayed the highest total phenolic (97.08 mg GAE (gallic …

Morpho-Environmental Variability For Scilla L. The Biogeographic Dynamism Under Climate Change Scenarios, João Rocha, Rubén Ramírez-Rodríguez, Francisco Amich, Darinka Gonzalez, Mário Santos, Reinaldo Cajaiba, António L. Crespí

Turkish Journal of Botany

This paper explores the correlations between morphological variability and range dynamics in western Eurasian-Mediterranean flora through a fluctuating asymmetry (FA) perspective across ten climate scenarios. We investigate the potential distribution of Scilla L. and its thermopluviometric correlations, and compare them with other three genera analysed previously, for western Eurasia and northern Africa (Baldellia Parl., Jasione L., and Ononis L. -Viscosae and Natrix sections-), considering past (22 Kyrs), present, and future conditions (2081-2100). By comparing "overlapped areas" (OA) with "non-overlapped areas" (NOA), we found two distinct groups of responses among genera: Scilla show higher morphological variability in NOAs, while Baldellia concentrate …

Implementation Of A New Non-Destructive Phytobenthic Index (Npi) With The Posidonia Biotic Index (Bipo) To Evaluate The Ecological Status Of The Turkish Aegean Coasts (Eastern Mediterranean), Ergün Taşkin, Aysu Güreşen, Furkan Bi̇lgi̇ç

Turkish Journal of Botany

Within this study, the ecosystem status of the Aegean Sea coasts of Türkiye (Eastern Mediterranean) was assessed using the Posidonia Biotic Index (BiPo) and a newly proposed Non-destructive Phytobenthic Index (NPI) according to the requirements of the Water Framework Directive (WFD 2000/60/EC). In addition, their relations with Land Uses Simplified Index for shallow water macroalgae (MA₋LUSI) were evaluated. The descriptors measured through NPI were: shoot density, cover, depth and type of lower limit of Posidonia meadows and cover of other macrophytic communities; Cymodocea/Zostera, canopy forming brown, coralligenous, opportunistic and alien macroalgae. The “good” status is presented by mean value of …

A New Species Of Polygonum Sect. Polygonum (Polygonaceae) From Southwest Of Türkiye, Kami̇l Coşkunçelebi̇, Suzan Kundakçi, Mutlu Gültepe, Serdar Makbul

Turkish Journal of Botany

Polygonum uysalii (Polygonaceae), a new species from the transition zone between Mediterranean and Irano-Turanian floristic region of Türkiye is described based on morphological and molecular evidence. The new species is similar to P. ekimianum and P. salebrosum endemic to Türkiye, but it clearly differs by its ovate-broadly elliptic leaf (not linear–lanceolate to narrowly elliptic- suborbicular), 0.9 ̶ 1.6 mm length pedicel (not 2.1 ̶ 4.88 mm), dark brown ochrea at base (not pale brown) and trigonous fruit (not weakly trigonous only in upper part or ovate-elliptic). Diagnostic characters and phylogeny of the new species are discussed with respect to taxonomy …

Oregon State Rank Assessment For Pt. Reyes Bird's-Beak (Chloropyron Maritinum Ssp. Palustre), Nora Dunkirk, Gabriel E. Campbell

Institute for Natural Resources Publications

Oregon state conservation status assessment for Pt. Reyes bird's-beak (Chloropyron maritimum ssp. palustre) using NatureServe methodology, 2024.

Responses Of Salvia Nemorosa L. To Silver Nanoparticle And Methyl Jasmonate Stimuli Under Salt Stress, Bi̇lal Andi̇ç, Pinar Orcan

Turkish Journal of Botany

The present study evaluated the effects of methyl jasmonate (MeJA) and silver nanoparticles (AgNP) on Salvia nemorosa L. under NaCl stress. To this end, total soluble sugar, total phenolic and flavonoid contents, total antioxidant capacity, H2O2 content, photosynthetic pigment, MDA, and proline contents, and enzymatic antioxidant activities were assessed. When the results for photosynthetic pigment contents were evaluated, the highest levels of total carotenoid content, chlorophyll a, and chlorophyll b were obtained with NaCl + AgNP + MeJA treatment. Under NaCl stress, MDA and H2O2 levels increased, but they decreased when AgNP and MeJA were applied. All treatment groups had …

Determining The Long-Term Effectiveness Of Seeding Post-Dam Removal In The Elwha River, Wa, Through Soil Seed Bank Analysis, Makenna Tabino, Rebecca Brown

2024 Symposium

Following the historic dam removal along the Elwha River in Olympic National Park, we are evaluating the impact of seeding in the former Lake Mills reservoir by examining the soil seed bank composition. The Elwha River had the largest dam removal project in history, and the second largest ecological restoration project in National Parks Service history. Active restoration (seeding and planting) took place in terraces and valley walls, the two dominant landform types found in the former reservoir. While the plant community in the former dam reservoirs is well documented, the soil seed bank remains unexplored.

My objective is to …

Designing A Decision-Support Tool For Fertilizer Recommendations In Oil Palm Smallholders, Rana Farrasati

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

Oil palm (Elaeis guineensis Jacq.), originally from West Africa, now accounts for 42% of global vegetable oil production and mainly includes key regions cultivated in tropical regions of Southeast Asia, West Africa, South America, and Central America. Despite its economic significance, the oil palm industry faces challenges of stagnant yields and large yield gaps, particularly among independent smallholders. These issues often stem from inadequate nutrient management practices and limited agronomic knowledge. Our objective was to quantify nutrient requirements for mature oil palm plantations as a basis to design a decision support tool (DST) for fertilizer recommendations. To do so, …

Assessing The Above- And Belowground Productivity Of Fall-Planted Cover Crop Cultivars In Nebraska's Diverse Ecoregions, Bridget Mckinley

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

Cover crops (CC) provide essential ecosystem services including soil conservation, nutrient cycling, and weed suppression, through the accumulation of aboveground (AGB) and belowground (BGB) biomass. While AGB has been widely studied, BGB contributions, particularly root development and distribution, remain less understood. This study evaluated fall-planted CC across three Nebraska ecoregions, assessing AGB productivity, BGB biomass, and correlations between ground cover, plant height, and AGB.

Thirty treatments, including grasses, legumes, brassicas, and mixtures, were evaluated over two fall growing seasons (2022–2023 and 2023–2024) at three UNL research centers in northeast, west central, and west Nebraska. AGB was highest at west site …

Bio-Based Sprayable Mulch For Weed Control In Row Crop Systems, Camila Chiaranda Rodrigues

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

Improving current crop productivity levels requires transformative advancements in management, engineering, and science. One of the main challenges is the increasing difficulty of weed management due to herbicide-resistant weeds. There is a growing need for alternative weed management methods to reduce pesticide use and improve environmental safety. An emerging technology that is being developed is spray-on films which could help address these challenges. Spray-on films are liquid solutions that after spraying on the soil will dry and form a physical barrier. The overall objective of this research was to evaluate the effectiveness of a chicken feather bio-based sprayable mulch film …

Twas Facilitates Gene-Scale Trait Genetic Dissection Through Gene Expression, Structural Variations, And Alternative Splicing In Soybean, Delin Li, Qi Wang, Yu Tian, Xiangguang Lyv, Hao Zhang, Huilong Hong, Huawei Gao, Yan-Fei Li, Chaosen Zhao, Jiajun Wang, Ruizhen Wang, Jinliang Yang, Bin Liu, Patrick S. Schnable, James C. Schnable, Ying-Hui Li, Li-Juan Qiu

Department of Agronomy and Horticulture: Faculty Publications

A genome-wide association study (GWAS) identifies trait-associated loci, but identifying the causal genes can be a bottleneck, due in part to slow decay of linkage disequilibrium (LD). A transcriptome-wide association study (TWAS) addresses this issue by identifying gene expression–phenotype associations or integrating gene expression quantitative trait loci with GWAS results. Here, we used self-pollinated soybean (Glycine max [L.] Merr.) as a model to evaluate the application of TWAS to the genetic dissection of traits in plant species with slow LD decay. We generated RNA sequencing data for a soybean diversity panel and identified the genetic expression regulation of 29 …

Scaling Individual Tree Transpiration With Thermal Cameras Reveals Interspecies Differences To Drought Vulnerability, Mostafa Javadian, Donald M. Aubrecht, Joshua B. Fisher, Russell L. Scott, Sean P. Burns, Jen L. Diehl, J. William Munger, Andrew D. Richardson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Understanding tree transpiration variability is vital for assessing ecosystem water-use efficiency and forest health amid climate change, yet most landscape-level measurements do not differentiate individual trees. Using canopy temperature data from thermal cameras, we estimated the transpiration rates of individual trees at Harvard Forest and Niwot Ridge. PT-JPL model was used to derive latent heat flux from thermal images at the canopy-level, showing strong agreement with tower measurements (R2 = 0.70–0.96 at Niwot, 0.59–0.78 at Harvard at half-hourly to monthly scales) and daily RMSE of 33.5 W/m2 (Niwot) and 52.8 W/m2 (Harvard). Tree-level analysis revealed species-specific responses to …

Growth Of Passionflower (Passiflora Incarnata) On A Green Roof Using Commercial Fertilizer Vs. Natural Compost, Siobhan Day, Corinne Parker, Carmyn Harrison, Lauren York

Science University Research Symposium (SURS)

Passionflower (Passiflora incarnata), Tennessee’s state wildflower, is valued for its ecological role as a pollinator plant and its historical significance to the Cherokee, making it an ideal candidate for green roofs that support biodiversity and urban sustainability. This study examined the feasibility of growing passionflower on a green roof and tested whether commercial fertilizer (Miracle-Gro) or natural compost would lead to greater growth compared to no fertilizer. Twelve plants were divided equally into three treatment groups: control, Miracle-Gro, and compost, with growth measurements taken weekly from September to November. Results suggest that passionflowers treated with Miracle-Gro achieved the most growth, …

Fire And Ant Interactions Mediated By Honeydew And Extrafloral Nectar In An Australian Tropical Savanna, Fernanda M. P. Oliveira, Carlos H. F Silva, Melinda L. Moir, Inara R. Leal, Alan N. Andersen

Natural Resources Research Articles

Fire is a major disturbance affecting ecosystems globally, but its impact on mutualisms has received minimal attention. Here, we use a long-term field experiment to investigate the impact of different fire regimes on globally important ant–honeydew and ant–extrafloral nectar (EFN) mutualistic interactions in an Australian tropical savanna. These interactions provide ants with a key energy source, while their plant and hemipteran hosts receive protection services. We examined ant interactions on species of Eucalyptus (lacking EFNs) and Acacia (with EFNs) in three replicate plots each of burning every 2 and 3 years early in the dry season, burning late in the …