Microbiology Commons^™

From Dust To Growth: Microbial Pathways To Extraterrestrial Farming, Stefani Capasso Villanueva, Nupur Kulkarni

Discovery Day - Daytona Beach

From Dust to Growth: Microbial Pathways to Extraterrestrial Farming addresses the fundamental challenge of sustaining long-term human habitation on other planets. In the era of the Artemis missions, establishing a cost-effective, bioregenerative food source is critical to reducing logistical dependency on Earth, and mitigating the physiological stressors faced by spacecrew through improved nutrition. This study initially investigated the viability of cultivating Mizuna, a proven ISS model organism, in a substrate of Martian regolith simulant amended with organic compost. Following iterative trials, it was found that the plant survival rate was extremely low, even after varying percentages of compost and simulant. …

Bridging The Gap In Science Research: Preparing Students For College- Level Research In The Sciences, Victoria Helwig, Yaoguang Li

UConn Library Presentations

Many first-year students enter college unprepared to fully engage with scientific literature and academic library resources. Drawing on experiences from academic librarians working with STEM students, this session explores common gaps in science research skills, including navigating databases, identifying scholarly sources, and understanding the structure of scientific literature. Participants will be introduced to practical strategies and classroom-ready activities to better prepare students for college-level research. Discussion questions: What science research skills do students struggle with most when entering college? How can high school instruction better support these skills? Where can librarians and educators collaborate to support student success?

Has Plant Domestication Compromised Plant Defensive Chemistry? Aphid Induced Stress In Tomatoes, Nhi Do, Satinderpal Kaur, Minxing Zhu, Esther N. Ngumbi

MICRO-CCS student projects

Tomato plants have natural defensive mechanisms.

Direct: Phenolics are secondary metabolites that can protect the plant by intoxicating the herbivores and/or producing strong repulsive odors.

Indirect: VOCs, Volatile Organic Chemicals, are gas phase signals that attract the predators of the attacking herbivore to the plant.

Domestication of plants may chemically alter these defenses by prioritizing fruit production over defensive traits.

We hypothesize that wild/ancient tomato plants would have a greater quantity of volatiles and increased concentration of leaf total phenolics compared to cultivated tomatoes during aphid herbivory.

How Does High-Oil Sorghum Change Potential Extracellular Enzyme Activity Across Soil Depth Profiles Under Drought Conditions?, Krystal Monique Role, Rounak Patra, Wendy Yang

MICRO-CCS student projects

Transgenic oil sorghum reallocates photosynthate-carbon (C) into vegetative lipids, accumulating nonstructural lipids in both shoot and root tissues. Altered plant C allocation and root lipid accumulation may shift root exudate chemistry, belowground C inputs, and microbial nutrient demand throughout the soil profile. While aboveground productivity in high-oil sorghum is well-characterized, its belowground impacts on soil microbial enzyme activity and exchangeable cation dynamics, especially across soil horizons under drought stress remain unknown.

Project objective was to find out how transgenic high oil sorghum (Tx-HO1) influences CNP acquiring extracellular enzyme activities and soil exchangeable cation dynamics across soil horizons under drought and …

Soil Microbiome Effect On Seedling Diseases And High Throughput Isolate Identification, Annalaysia Smith, Mara Krone, Santiago Mideros

MICRO-CCS student projects

The soil microbiome has a substantial effect on disease suppression. Organic farming is a practice used to create a more diverse microbiome which can create disease suppression. Different agricultural practices such as fertilization and rotation system are known to affect the microbiome (Schlatter et al 2017). Therefore, it is important to study the effects of different microbiomes on disease suppression. Furthermore, methods are necessary for quantifying the effect of disease suppression on specific pathogen populations. To do this, it is important to properly identify the pathogens.

Objectives:

1. Test if different nitrogen treatments cause variations in organic soils disease suppression. …

Fungal Diversity In Lespedeza Cuneata Roots, Gwendolyn Happ, Sophia Mcdade, Anthony Yannarell

MICRO-CCS student projects

Background

• Plants form a relationship with fungi that can be beneficial or harmful
• Fungi may grow on the plant surface, within plant tissues, or around roots
• Plants release compounds that invite fungi to their roots and chemicals  that can diminish unwanted fungi

Why Lespedeza cuneata? 

• Invasive that competes with native plants and damages biodiversity within plant and animal communities
• Alters soil microbiome
• Expansive seed bank and deep root system
• Understanding its microbiome can help in understanding invasive species success and ecology

Evaluating Soil Health And Crop Yield In Louisiana Agricultural Systems: Impacts Of Best Management Practices And Prediction Models, Hector J. Mendoza Lagos

LSU Doctoral Dissertations

The adoption of conservation management practices is critical for improving soil health, enhancing nutrient use efficiency, and sustaining crop productivity in row crop systems in Louisiana. This study evaluated the role of conservation agronomic practices, soil biochemical indicators, and machine learning predictive models to improve soil nutrient dynamics, soil health indicators, microbial communities (MC), and crop productivity on a corn (Zea mays L.) research plot scale and in a commercial forty-hectare cotton (Gassypium hirsutum L.)-corn-soybean (Glycine max L.) rotation system in northeast Louisiana. The objectives of the study were to evaluate soil nutrient dynamics and MCs under …

Belowground Consequences Of Herbivory In Tomatoes And Cucumbers And Its Lasting Effects, Anthony Ignacio Barrera

Theses, Dissertations and Culminating Projects

Plants recruit soil microorganisms to help mediate biotic stressors such as herbivory, forming dynamic communities in the rhizosphere known as the root microbiome. This study investigated whether artificial herbivory could induce shifts in the root microbiome of tomato (Solanum lycopersicum) and cucumber (Cucumis sativus) and whether those shifts could be transferred to subsequent plants as a soil legacy effect. Plants were grown in sterilized or non-sterilized soil with or without simulated herbivory across two experimental phases, with Phase 2 plants receiving inoculum conditioned by Phase 1 plants. Bacterial community composition was assessed via 16S rRNA amplicon sequencing and analyzed using …

Bottles, Butterflies, And Biomass: Recycled Glass Sand, Microbial Additions, And Herbivory Effects On Milkweed Growth, Kealey Skinner

Honors Theses

Plant-soil-microbe interactions are integral components of ecological networks and drive ecosystem function from the bottom-up. Whereas herbivores regulate ecosystem function from the top-down, having opposing and potentially complementary effects on ecosystem function. My thesis sought to understand how below-ground microbial communities contribute to herbivore preference and plant biomass across varied soil substrates. My thesis asked: how do substrate and soil microbial communities influence herbivore preference and plant biomass accumulation on swamp milkweed (Asclepias incarnata)? To address this question, seedlings of A. incarnata were sown in 2.5 cm wide × 10 cm deep pots filled with either natural beach sand or …

Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach

Theses and Dissertations

Bacterial organisms can “talk” with one another on a colony-wide scale using a communication system known as quorum-sensing (QS) via chemical signals. These signals are produced at a basal rate throughout the life of the bacteria and are classified as autoinducers, which diffuse across the cell membrane. Once the critical concentration is reached, they begin to diffuse back into the cell and initiate a phenotypic change. As these signals exist outside the membrane of their producer, they are also accessible to other organisms. It has already been noted that some plant species uptake these compounds through their roots and break …

Dried Water Treatment Residuals Might Be An Option To Reduce Soluble Reactive Phosphorus Release From Soils, Katie B. Mckay

Biological and Agricultural Engineering Undergraduate Honors Theses

Nonpoint source pollution from agricultural landscapes contributes to freshwater eutrophication, with legacy phosphorus (P) in soils potentially driving soluble reactive phosphorus (SRP) losses to surface waters. The objectives of this study were to evaluate SRP adsorption by dried water treatment residuals (WTRs) produced by Beaver Water District, quantify reductions in soil SRP release across increasing WTR application rates, and compare dried WTR performance to prior WTR studies.

Dried WTRs (~98% solids) were assessed using batch sorption experiments and soil core incubations. Phosphorus sorption was measured by mixing WTRs with CaCl₂ solutions containing increasing SRP concentrations and fitting results to …

Sustainable Mitigation Of Microplastic Pollutants Using Native Plant Species, Antonio De Jesus Martinez De La Rosa, Emily Lancaster

Research Papers

Microplastics (MPs) are defined as small plastic particles that come from the degradation of plastics [Ziani et al. 2023], that hold a regular or irregular shape, ranging from 1μm to 5 mm [Campanale et al. 2025]. This diminutive size makes them virtually impossible to remove once released into the environment[Lee et al. 2023]. Furthermore, biological, chemical, and physical processes break MP's further down in the environment, causing them to exist in nano-level sizes (1nm-1μm) [Lee et al. 2023], further exacerbating their threat to critical habitats. However, recent studies have shown MP contamination expands beyond the natural environment as recent studies …

Life Line Spring 2026, Jonathan Atwood

Life Line - The Biology Department Newsletter

In This Issue:

Greetings and Farewell: Part Deux; Signs for Trees; Passing of Dr. Mary Gahbauer: a Beloved Friend and Colleague; Dr. Lisa Marr Retires; The Department Welcomes Dr. Ann Feke; Dr. Kevin Svitana Retires; Ms. Donna Rhodeback Retires; Tucker Adds Swan Specimen to Otterbein's Collection; An UnbeLEAFable Year for the Otterbein Chapter of Botanical Society of America; Field Geology Course Visits Death Valley and Beyond; Agar Art: An Unexpected Canvas; Dr. Kevin Svitana Wins the Anderson Award for Outstanding Contribution to Groundwater Research; Introducing Opi: A New Face for Zoo and Conservation Ambassador Work; Michael Hoggarth, Professor Emeritus, Wins …

Sustainable Mitigation Of Microplastic Pollutants Using Native Plant Species, Antonio Martinez

Posters - 2026

Microplastics (MPs) are defined as small plastic particles that come from the degradation of plastics [Ziani et al. 2023], that hold a regular or irregular shape, ranging from 1μm to 5 mm [Campanale et al. 2025]. This diminutive size makes them virtually impossible to remove once released into the environment[Lee et al. 2023]. Furthermore, biological, chemical, and physical processes break MP's further down in the environment, causing them to exist in nano-level sizes (1nm-1μm) [Lee et al. 2023], further exacerbating their threat to critical habitats. However, recent studies have shown MP contamination expands beyond the natural environment as recent studies …

Impact Of Legacy Amf Communities On Vegetative Growth & Yield Of Soybean, Dylan Habeeb, Connor Morozumi, Natalie Christian

The Cardinal Edge

Soil microbial communities are increasingly recognized as an important factor in sustainable agriculture. Arbuscular mycorrhizal fungi (AMF), are key players in these communities, known to benefit their plant host in a number of ways, such as increased nutrient uptake. Plants can partner with multiple AMF species; however, little is known about how interactions between multispecies communities of AMF impact plant growth and yield. In an agricultural setting, the long-term development of these communities following practices such as rotational planting or cover cropping is also an important consideration, but there is little research on the long-term legacy of AMF communities or …

Humanity Is Evolving Its Consciousness: The Role Of Archetypal Energies As Guides During An Unfolding Weeding Out And Alignment Process, Carroy U. Ferguson

Psychology Faculty Publication Series

Humanity is evolving its consciousness at individual and collective levels.  Given these seemingly tumultuous times, as of this writing (January 2026), to make such a statement may sound like a strange thing to say.  However, I suggest that if you are alive today and if you are reading these words, these are the very times for which you were born—to assist Humanity as it evolves its consciousness with your unique gifts, whatever they may be.  That is, this period of our individual and collective human being-ness may be characterized as an unfolding period of weeding out and alignment with the …

Effects Of Volatile Organic Compounds Produced By Temperature-Adapted Microbes On Duckweed Growth, Phaedra Yael Stemp

Honors Theses and Capstones

As host-associated microbes adapt to their abiotic environment, these adaptations can affect their host species as well. Previous research showed that varying temperatures and volatile organic compound (VOC) production can affect microbial benefits to hosts. This experiment analyzed how 27 microbes pre-adapted to different temperature conditions affected growth of their host, common duckweed plants, comparing effects of direct contact with microbes, effects of microbe VOCs alone, or both. Each microbe was pre-adapted to one of three temperature regimes: “Northern” at 28 °C, “Southern” at 33 °C, and “Extreme” at 36 °C. We then grew duckweeds in I-plates with each microbe …

Investigating Microbe-Mediated Temperature Tolerance In Lemna Minor, Matthew Thomas Farbaniec

Honors Theses and Capstones

Temperature limits plant growth and survival more than many other environmental variables, and increases in the frequency of extreme hot or cold weather events pose significant challenges for plant growth and crop yields. Previous studies have shown that bacteria, fungi, and other microorganisms associated with plants ( i.e., the plant microbiome) can influence host response to temperature stress. These same microbes have their own temperature tolerances. We investigated whether microbial temperature tolerance correlates with plant resilience using an aquatic plant model, Lemna minor, and isolates derived from its microbiome. Microbial isolates were assessed at −10°C, 4°C, and 32°C for …

Influence Of Microbial Communities And Dilute Heavy Metals In Green Manure On Growth In Lactuca Sativa, Robert Lemay

Student Research Projects

This experiment investigated the effects of a green manure (Lemna minor, common duckweed) grown in varying levels of heavy metals and inoculated with local microbiomes on a crop (Lactuca sativa, volcana lettuce). The growth and health of the duckweeds were measured via root length and biomass, and the health of the lettuce crop was measured via head diameter and biomass.  Two levels of heavy metal concentrations were based on real-world stormwater runoff data to mimic an agricultural environment where accumulation of metals in local water bodies may be absorbed into green manure duckweeds. One microbial treatment and …

From Theory To Ecosystems: Exploring Biodiversity And Ecosystem-Function In Pitcher Plant (Darlingtonia Californica) Microbial Communities, Gavin Sutter

Cal Poly Humboldt theses and projects

The relationship between biodiversity and ecosystem-function (BEF) has been a central focus of ecological research for the last three decades, yet the role of space in shaping BEF relationships remains relatively unknown. Research has shown that community diversity and composition can strongly influence productivity, nutrient cycling, and decomposition, but much of this work treats communities as spatially isolated, leaving open how dispersal and other spatial processes shape BEF at broader scales. To begin addressing this gap, I used microbial communities inhabiting Darlingtonia californica pitcher plant leaves to evaluate how spatial organization and successional change shape biodiversity and ecosystem-functioning. I quantified …

Characterizing Gut Microbial Communities And Symbiont-Mediated Detoxification In Herbivorous Insects, Rachel C. Vargas

Biology Dissertations

Insect gut bacteria are vital contributors to host physiology, yet the broader prevalence and fitness implications of symbiont-mediated detoxification remain poorly understood. This thesis investigates these dynamics across three research chapters. Chapter 1 uses 16S rRNA sequencing to characterize how grasshopper gut microbial communities vary across species, dietary breadths, and gastrointestinal segments. Chapter 2 evaluates the detoxification capacity of over 150 bacterial isolates from diverse herbivores against the plant allelochemicals phenethyl isothiocyanate, rutin, and chlorogenic acid to determine if host dietary specialization predicts microbial metabolic ability. Finally, Chapter 3 employs fitness bioassays to test whether inoculating generalist herbivores with detoxifying …

The Geminivirus Al2 Protein Interacts With Host Proteins Involved In The Plant Antiviral Response, Pheobean Atieno Odongo

Graduate Research Theses & Dissertations

Geminiviruses are economically important plant DNA viruses infecting a broad range of plant species and causing devastating crop diseases, resulting in up to 100% crop loss. As a result of these heavy losses on food and cash crops, these viruses represent a new threat to global food security and sustainability. In this research, I use Tomato golden mosaic virus (TGMV) to study host-virus relationships with an overall goal of developing sustainable and eco-friendly crop resistance. TGMV belongs to the Geminivirus subgroup, Begomovirus, that is characterized by a split genome consisting of two single-stranded circular DNAs. The TGMV genome encodes proteins …

Straw Cover Increases Garden Soil Microbial Biodiversity, Emory Walker, Mara Welty, Emma Creviston

The Journal of Purdue Undergraduate Research

No abstract provided.

Effects Of Supplemental Led Lighting And Biofertilizer On Yield And Fruit Quality Of Japanese Strawberry Cultivars In Indonesia, Reginawanti Hindersah, Febby Fitriyani, Kenji Endo, Masakazu Nakayama, Syariful Mubarok, Gita Bina Nugraha

Jurnal Kultivasi

Growing strawberries in soilless substrates in the greenhouse relies on fertilizers and supplemental light to boost yield and fruit quality. The research evaluated the properties of the biofertilizer and its effectiveness on the yield of Japanese strawberry cultivars Nanatsuboshi and KS-75 under controlled greenhouse conditions, with and without light-emitting diodes (LED) as supplemental light. The cell viability and plant-growth-promoting properties of a liquid consortium biofertilizer consisting of nitrogen-fixing bacteria and phosphate-solubilizing microbes, were characterized. Laboratory analysis confirmed the biofertilizer's composition, and a greenhouse experiment using a completely randomized design tested treatments of biofertilizer, LED, and their combination. The biofertilizer contained …

The Effects Of Nanobubble Fertigation And Soil Conditioners To Improve Nutrient Dynamics, Soil Microbial Activity, And Chili Productivity, Betty Natalie Fitriatin, Euis Ahah Rokayah, Elsa Naila Elmyra, Tualar Simarmata, Nicky Oktav Fauziah, Hanif Fakhrurroja

Jurnal Kultivasi

Drip fertigation is a fertilization method that integrates nutrient delivery with an irrigation system, which is capable of optimizing the direct delivery of nutrients to the root zone. This experiment aims to investigate the effect of drip fertigation with nanobubble technology, and soil conditioners on the population of Phosphate-Solubilizing Bacteria (PSB) and Azotobacter spp., available phosphorus, total nitrogen, growth, and yield of red chili. The study used a Strip Plot Design with two factors and three replications. The first factor was nutrient application (solid NPK fertilizing as control; drip fertigation; and drip fertigation with nanobubble technology), and the second factor …

Advancing Louisiana's Cropping Systems: Sustainable Bioenergy Production, Cover Crops, And Technology Integration, Pedro R. Carrillo

LSU Doctoral Dissertations

The adoption of cover crops in Louisiana is lower than the national average, underscoring the need for region-specific research to address environmental challenges and demonstrate the short-term benefits of these practices within existing production systems. This research evaluated the integration of cover crops (CC) in energy cane (Saccharum spp.) and no-till cotton systems, focusing on their effects on soil health, nitrogen (N) management, and biomass production. Soil health indicators (SHIs), including enzymatic activities (β-glucosidase, β-glucosaminidase, and urease), protein N, inorganic N concentrations (nitrate and ammonium), soil organic matter (SOM), and microbial community composition assessed through ester-linked fatty acid …

Solvent Extracts Of Pulvigera Papillosa (Orthotrichaceae) Show No Antimicrobial Properties In Disk Diffusion Tests, Ryan A. Solorzano, Justin Paulin, Grayson Prater, Michael Lanier

Humboldt Journal of Microbiology

Abstract As antibiotic-resistant bacteria become more prevalent, the search for novel forms of antibiotics in the natural world has become an increasingly worthwhile endeavor. Many mosses have been found to contain antimicrobial properties, including those in the family Orthotrichaceae. Pulvigera papillosa, an Orthotrichaceous moss native to California, has thus far not been investigated to determine whether it contains antimicrobial properties. Extraction techniques using polar and nonpolar solvents have proven to be effective in extracting the secondary metabolites that allow mosses to defend themselves against a hostile microbial world. This study takes a preliminary look into the antimicrobial properties of P. …

Comparative Analysis Of Taproot And Fibrous Root System Microbiomes Under Flooding Stress, Natalie S. Kozlowski, Leighanna Jake

Humboldt Journal of Microbiology

There has been increased interest in understanding how the microbiomes of vascular plants respond to flooding stress and, many studies have focused on monocotyledonous plants with fibrous root systems. This leaves a gap in knowledge of dicotyledonous plants with taproot systems, as previous studies have been in the context of flooding to cropland affecting major food crops which are often monocotyledonous plants with fibrous root systems. Since the structural and functional differences between these root systems may influence microbial community stability and response to flooding conditions, a study looking at both is long overdue As such, this study aims to …

Evaluation Of Anti-Bacterial Efficacy Of Ginger, Resin Gum, And Nigella Sativa Irrigants Against Enterococcus Faecalis: An In Vitro Study, Iman El Ghazzawy, Leen Imad Hasbini, Reem Chamseddine, Wael Betbout, Roula Abiad

International Arab Journal of Dentistry

Objectives: To evaluate the antibacterial efficacy of Ginger, Resin Gum, and Nigella Sativa, against Enterococcus Faecalis.

Methods: Thirty-eight extracted single-rooted premolars were inoculated with E.faecalis, except the negative control, and incubated for 4 weeks. After instrumentation samples were divided into 4 groups (n=7) according to final irrigation: NaOCl+EDTA (Group A), Nigella sativa (B), Resin Gum (C), Ginger (D), plus 2 control groups (n=5): Saline (E), and Saline without bacterial inoculation (F). Cultures were collected at baseline and after irrigation.

Results: One-way ANOVA showed that in groups A-D a statistically significant reduction of bacterial load was observed at …

The Effects Of Plastic Mulch And Irrigation On Hemp Chemistry And Leaf Endophytes, Allison Rietman, Connor Morozumi, Robert C. Pearce, Natalie Christian

Journal of Agricultural Hemp Research

As an emerging crop, cultivation techniques for industrial hemp (Cannabis sativa L.) are still being developed and optimized. For example, irrigation and plastic mulching are some management practices that have been touted for their benefits in improving crop quality. Both techniques ensure ample water availability, which has often been attributed to improving hemp cannabinoid and terpene composition. In this study, we examined how supplemental irrigation implemented in a plastic mulch system influenced the cannabinoid and terpene profiles of one cultivar of CBD hemp, Lifter. We grew industrial hemp in field with plastic mulch and applied regular irrigation to one group …