Research Guides: Scholars Symposium 2023: Science & Mathematics

Past, Present, and Future Research into Domestication Syndrome in Animals: Evaluating the Trajectory of Domestication Syndrome Research

by Daniel Ormsbee (Undergraduate)

The origin of what is now known as the domestication syndrome can be traced back to the seminal works Origin of Species, as well as Variation of Plants and Animals Under Domestication, both published by Charles Darwin in 1859 and 1868 respectively. In these works Darwin first examined the set of disparate traits shared by domesticated animals and proposed a mechanism for their unexpected emergence. While the mechanism Darwin proposed has been disproven, current scientific research proposes two genetic mechanisms for these traits’ emergence and inheritance. Wilkins, an evolutionary biologist, has extensively researched domestication and has proposed the Neural Crest Cell/Domestication Syndrome (NC/DS) Hypothesis wherein proposed genetic changes in the genetic regulatory networks (GRN) controlling neural crest cell (NCC) development give rise to the different traits found in the generalized domestication syndrome. Wright disagrees with this assertion, citing that there is inconclusive evidence to propose that this mechanism is responsible for the many traits of DS. However, Wright struggles to propose a testable hypothesis to counter that proposed by Wilkins. Moreover, throughout a series of commenting publications Wilkins was able to clarify definitions ,and put forth examples of quantitative and qualitative studies to support his initial inferences. Therefore, given the prevalence of supporting research for the NC/DS hypothesis, we put forth possible areas of future research given the abstraction of viewing biological systems as computational systems with sets of inputs, outputs, hardware, and software.

Can We Estimate Soil Respiration from the Sky?

by Mark A. Gathany (Faculty Advisor), Kassi Eskeldson (Undergraduate), Jonah Lynch (Undergraduate), Molly Moses (Undergraduate), Elizabeth Tan (Undergraduate), and Carl Weaver (Undergraduate)

The process of soil respiration results in the release of CO2 from the soil. A large body of research has found that variables such as soil moisture, plant cover and density, and soil quality are all strong predictors of soil respiration. At the same time remote sensing has been shown to make strong predictions of these variables based on surface reflectance. Currently there is a scale mismatch between soil respiration measurements and remote sensing techniques that estimate respiration rates from sub-meter points or 0.1 ha areas, respectively. In this study we set out to assess as to whether this scale discrepancy may be overcome by using examining as to whether imagery from a drone-based multi-spectral sensor is correlated with soil respiration. Further we assess whether there was a significant difference (a = 0.05) between adjacent plant communities. We found that soil respiration was statistically different (p = 0.002) between the lawn (= 4.33 µmole m-2 s-1) compared to the prairie (= 2.01 µmole m-2 s-1). Our correlation analysis revealed several strong relationships between soil CO2 respiration rates and the drone imagery. Specifically, we found r-values of -0.40 and -0.49 between soil CO2 efflux and Red 650 and Red 668 bands. We plan to continue to assess these data to offer guidance for future analysis into the agricultural applications of drone based imagery.

Early Season Ohio Midge (Diptera: Chironomidae) Species

by Michael Mendel (Faculty Advisor), Catherine G. Harbach (Undergraduate), Grace S. Leiford (Undergraduate), Sara C. McElroy (Undergraduate), Landon P. Smith (Undergraduate), and Carson S. Gehmann (Undergraduate)

Ohio’s Environmental Protection Agency (OEPA) routinely collects macroinvertebrates from streams in the summer during a designated sampling period of between June 15th and September 30th. Data collected outside of those dates are not admissible for water quality evaluations, according to state regulations. By design, this system will unfortunately exclude those species which emerge earlier in the year, usually during the spring, even though these species may provide considerable information on stream water quality. These early season species will mate and lay eggs, which will hatch sometime over the summer or fall, yielding individuals which, if present in the late summer collections, are too small to identify to species. Our study focuses on early season collections in the Western Allegheny Plateau Ecoregion of Ohio, and has collected a number of species that are not commonly found during water quality surveys, some of which are not listed on OEPA’s Master Taxa List for the state of Ohio, such as Orthocladius annectens and Hydrobaenus sp. O. While these species are not necessarily rare, they are probably infrequently (or never) collected because of the time they are present as mature larvae in Ohio’s streams. The locations of the early season midge species collected were mapped in the WAP using the Geographic Information System. Identifying these early season species and mapping their locations adds to our understanding of the life God has created to occur in our streams.

Assessing Midge Larval Distribution in the Western Allegheny Plateau Ecoregion, Ohio

by Michael Mendel (Faculty Advisor), Gavin J. Couture (Undergraduate), Chandler C. Emerson (Undergraduate), Abigail S. Gosselink (Undergraduate), Stephen F. Lehmann (Undergraduate), and David J. Pride(Undergraduate)

Midge (Diptera: Chironomidae) larvae are widely distributed in flowing water and can act as important biological indicators of water quality. Midge larvae are difficult to identify to species and many studies limit the taxonomic resolution to family or genus, losing valuable information necessary for assessing stream quality and the diversity of God’s creation. The goal of this study is to identify midge larvae to the lowest taxonomic level (preferably species). Larvae were collected from riffles, runs and pools in small to medium-sized streams located in the Western Allegheny Plateau Ecoregion (WAP) from mid-March to mid-April. Mouthparts and other morphological structures were examined under a compound microscope to identify the midge larvae. The locations of the midge species collected were mapped in the WAP using the Geographic Information System. Rarefaction and extrapolation curves (including associated confidence intervals) for midge species richness for the WAP were developed using the software program EstimaeS. The streams where the most common and least common midge species occurred were compared based on gradient, sedimentation and riparian habitat.

Florida Panther Habitat Loss and Potential Danger to Species Stability

by Stephen Lehmann (Undergraduate), Meredith Smith (Undergraduate), and Ben Aiken (Undergraduate)

The Florida Panther is an endangered species of panther that only inhabits southern sections of Florida primarily around the Everglades. Their habitat has been slowly degraded over decades to the point where their groupings are becoming more clustered. This can be problematic as their social behaviors are known to be solitary and territorial animals. This aggression could lead to even more Florida Panther destruction and endangerment. The purpose of this poster is to show the grouping and habitat loss of these creatures and take data from ther movements to see if their social interactions are being forced to happen more often or not.

Karst Mapping and Periglacial Influences in Highland County, OH

by Andrew Swift (Undergraduate)

Sinkholes that are a result of karst development were mapped by the Ohio Geological Survey (OGS) in the Sinking Spring quadrangle of Highland County, OH in 2017. However, since that study, new sinkholes have developed and preexisting ones have deepened on an agricultural property owned by R. Epley, Hillsboro, OH. The sinkholes have posed a great risk to livestock and farming operations and new ones may continue to form. This study will follow the same procedures of the OGS to map the new sinkholes but also determine the geologic history of the of the karst development. It is known that the karstic topography is a direct result of springs in the area dissolving the underlying carbonate bedrock. However, the property sits at the margin of where the last continental glacier once covered Ohio and is therefore periglacial in nature. Periglacial geomorphology can have many effects on a landscape, and the resulting meltwater from glacial retreat can possibly contribute to karst formation. Using field observations, aerial imagery obtained from an unmanned aerial vehicle (UAV), and research on the geomorphology and underlying geology of the area, the most likely causes of the karst development will be determined. The study’s results will possibly provide information for area landowners regarding past, present, and future sinkhole formation.

Dinosaur Fossil Preparation and Identification

by Sarah Stone (Undergraduate)

An essential part of the field of paleontology is knowing how to prepare fossil specimens and having the ability to identify them as accurately as possible. Some key aspects of coming to a proper identification are studying the formation in which the specimen was discovered, and comparing the fossil to the most detailed current osteological descriptions. For this study, a plaster-jacketed dinosaur specimen was made available to the Cedarville University Geology Program by Answers in Genesis for preparation and analysis. There are a few initial challenges in regards to this project. The first is that the unidentified specimen was found in a transition zone between the Brushy Basin and the Salt Wash members of the Morrison formation. As a result, the member is difficult to identify. The second is that the specimen’s integrity is very weak, resulting in extreme difficulty with preparation. This project encompasses research into sedimentology and osteology, geochemical experimentation, and fossil preparation. The project concludes with a confirmation of the formation member and a successful identification of the specimen, including type of bone as well as genus and species.

Geospatial Analysis of Cedarville University Wells and Water Table

by Emma Henze (Undergraduate)

The focus of this research is to develop updated and accurate educational material for future classroom work in the Geology and Environmental Science departments. In past lab activities, limited availability of data related to the Cedarville University wells has acted as an obstacle to educational goals; in completing this work, future students and educators will have the opportunity to make use of the collected data and corresponding maps. This project will analyze the local lithology using well log data from Cedarville University wells. Precise locations of each well located on the university’s property will be recorded using centimeter-accuracy GPS equipment and utilized to create an interactive digital map. Further study of the well logs will be conducted so as to create a groundwater contour map for the university’s well field and adjacent property. The combination of these datasets will serve as tools for future geoscience courses and increase the efficiency of lab activities.

Wetland Easement GIS Mapping Analysis

by Nathanael Luke Harkrider (Undergraduate)

Wetlands are important to the environment because they provide habitats for local flora and fauna. They also help prevent flooding as they are catchment basins for clean groundwater. The chosen property is located in Camden, OH. It has been put into a governmental wetland easement for the purpose of protecting existing wetlands and creating new habitats.

This project aims to gather spatial and attribute data for several wetlands on the chosen property and create an interactable wetland map. The map will include varying layers for mature and newly developed wetlands. Newly developed wetlands not included in the initial government wetland survey data will be noted separately. Soil samples will be gathered around each wetland area to determine their extent and correlate soil types with online state databases. Data will be compared to official databases to determine if onsite measurements differ.

The results from this project will provide a better understanding of wetland development and the effectiveness of the government wetland easement program. If wetland habitats have been maintained or increased over time it will be seen as a successful initiative for habitat restoration.

Comparing drone- and ground-based forest canopy measurements

Traditionally there have been two different methods to study forest canopies. One method includes the measurement of a canopy closure, which focus on leaf density from an aerial perspective. Another method is canopy cover. This method focuses on the light density from a ground level view. Measuring canopy cover is fundamental to understanding ecosystem structure and function. As technology has progressed, there is great potential to develop our understanding of canopy cover by measuring the canopy from above using a drone. In this study we sought to assess the ability of drone based imagery to predict ground based measurements of leaf area index (LAI, m2 leaf m-2 ground). We collected hemispherical images of the forest canopy at 30 points in a 5-acre woodlot. At the same time we collected above canopy imagery with a drone mounted 10-band multispectral sensor. We found mean LAI = 3.16 with 1.26 and 4.96 as the minimum and maximum, respectively. We found that LAI correlated was positively correlated for 8 of the 10 bands. Six of the 10 bands had r-values > 0.1 with the Blue 444 band having the strongest correlation (r = 0.177). We are pursuing additional image processing refinements and statistical analysis. Our expectation is that this work will be useful in developing a deployable and scalable technique that will improve our understanding of forest ecology, management, and restoration.

Is Sinkhole Formation Structurally Controlled?: A Lineament Study with the use of ArcGIS of the Epley Property and the Sinking Spring 7.5 Minute Quadrangle, Ohio

by Daniel John Burton (Undergraduate)

The phenomenon of sinkholes is common in karst terrane, but it is difficult to understand how or where they occur since much of the process occurs below ground. Digital elevation models (DEMs) generated from LiDAR has been used to create maps depicting sinkholes, sinks, depressions, and other suspect karst features. Landsat data has been used to create lineaments and lineament maps. Lineament maps have been used to study structural patterns in geology and can be used to study the below-surface geology of sinkholes and karst. With the use of ArcGIS and filtering, LiDAR, Landsat, and other aerial imagery can be modified to isolate terranes for easier lineament mapping. The Epley property and the Sinking Spring 7.5 minute quadrangle in Highland County, Ohio has been selected as the candidate for determining whether sinkholes and karst features are structurally controlled based lineament mapping.

Analyzing Occupancy and Habitat Use of Wildlife in a Heavily Agricultural Area

by Mark Gathany (Faculty Advisor) and Carson S Gehman (Undergraduate)

In recent years, many biologists have turned to using motion-activated cameras as a method of sampling wild animal populations. This alternative is relatively cost-effective and noninvasive compared to the traditional direct observation study. We plan on utilizing this method to collect information about local wildlife movement and land use. There are two major aspects of this project. First, we hope to compile picture data of various mammalian species for use in estimating species occurrence. The second aspect of this research is to analyze a heterogeneous landscape to determine the preferred habitat for said species based on capture data. The area of study is a 200-acre piece of land, composed of both woodland and crop fields with minimal topographical change, located outside of the town of Cedarville on university property. We hope to deploy ten game cameras throughout the study area and collect data for 4-5 weeks. We will analyze this data in tandem with lidar (light detection and ranging) data collected by the Ohio Geographically Referenced Information Program (OGRIP) of the Ohio State Government to determine habitat preference. The combination of these two aspects will allow us to quantify the usage of relatively isolated farmland by local wildlife in a region of heavy agricultural impact.

Using GIS to Predict Wildfire Risk in California National Forests

by Andrew Swift (Undergraduate)

Wildfires have increased in occurrence over the past few decades dramatically. California is hit harder than most states when it comes to wildfires and contains 18 national forests managed by the US federal government. Response to fires are often spread thin due to various factors so forest protection and fire suppression would be vastly made more efficient if it was possible to predict risk of wildfires and divert resources in reserve to those areas. Using ArcGIS Pro and data from LANDFIRE, the Angeles, Sierra, and Klamath National Forests are analyzed based on their slopes, slope aspect, type of land cover, and proximity to roads in order to assess how susceptible to wildfires they are whether it is human or naturally induced. These three forests are spread throughout the state to provide a generalized assessment of California national forests. This will also provide a comparison of southern, middle, and northern regions in the state and how susceptible each one is to wildfires. This information can be updated and redone as often and wherever it is needed in order to keep firefighting resources and personnel located in the optimal positions for rapid response and what to expect should the forest undergo a burn.

H3K27 is involved in mitotic regulation in Tetrahymena thermophila

by Heather G. Kuruvilla (Faculty Advisor) and Abigail Bautista (Undergraduate)

Diffuse intrinsic pontine glioma (DIPG) is a childhood cancer for which no effective treatments currently exist. DIPG patients have a point mutation in histone H3 resulting in lysine 27 being replaced by methionine. Since lysine residues on histone tails are sites for methylation and acetylation, common post-translational modifications which affect gene regulation, the lack of lysine at position 27 is correlated with dysregulated cell growth in DIPG. Since Tetrahymena thermophila have constitutively active growth pathways as well as homologs of histone H3 with lysine at position 27, we used these protozoans as a model system for studying the role of H3K27 in mitotic regulation. Using the antimitotic drug BAY-293, we found an increase in trimethylation at H3K27 as well as a statistically significant decrease in acetylation at H3K27 in cells that were exposed to BAY-293 when compared with DMSO controls. These data suggest that H3K27 is involved in gene silencing in Tetrahymena thermophila when exposed to BAY-293, indicating a role for H3K27 in mitotic regulation. Similar functions may be associated with H3K27 in other systems as well.

Can liposomes be used to transfect Tetrahymena thermophila for CRISPR/Cas9 studies?

by Heather G. Kuruvilla (Faculty Advisor), Arianna Bland (Undergraduate), Miki Fath (Undergraduate), Caleb Faul (Undergraduate), Abigail Hall (Undergraduate), Samuel Johnson (Undergraduate), Sarah Kinder (Undergraduate), Katrina Mills (Undergraduate), Abigail Misselbeck (Undergraduate), Chukwuemelie Ojukwu (Undergraduate), Nathan Spottswood (Undergraduate), Emily Watcher (Undergraduate), Ethan Wang (Undergraduate), and Samantha Wolff (Undergraduate)

CRISPR-Cas9 editing is a powerful tool for making genome changes in organisms. The free-living ciliated protozoan, Tetrahymena thermophila, has been used for decades as a model system for eukaryotic genetic and epigenetic phenomena. Because of this, there is a great deal of interest in adapting the CRISPR/Cas9 system to Tetrahymena. Plasmids containing the gene for Cas9 nuclease are currently available for transfection into Tetrahymena. However, the transfection protocols which are currently used in this organism, electroporation or biolistic transformation using a gene gun, are both expensive and inefficient. We are attempting to use liposomes in order to transfect Tetrahymena with the Cas9 nuclease. Our hope is to develop a protocol that would allow for a more efficient, less expensive transfection platform, facilitating further development of CRISPR-Cas9 editing in this system.

Tetrahymena thermophila as an Indicator Species for Climate Change

by Heather G. Kuruvilla (Faculty Advisor), Haleigh Eckert (Undergraduate), Tara Keller (Undergraduate), Katarina Mills (Undergraduate), Isaac Seabra (Undergraduate), Taylor Strickland (Undergraduate)

Tetrahymena thermophila are free-living, nonparasitic unicellular eukaryotic organisms that are generally representative of other microorganisms. For this experiment, we were interested in measuring the change in gene expression caused by stressing Tetrahymena, specifically by increasing the culture temperature. In our studies, gene expression was observed by measuring mitotic rates, acetylation and methylation of histones, and mitochondrial biogenesis in response to heat shock. We used a variety of techniques to accomplish this, including cell counting via hemocytometer, immunofluorescence visualization and quantitation, and staining with MitoTracker™. Tetrahymena's response to the increase in environmental temperatures could give us some insight into the effects of climate change on unicellular organisms.

Establishing Soil Organic Matter Benchmarks in Active Agricultural, Restored Prairie, and Conservation Reserve Program (CRP) Soils

by Mark A. Gathany (Faculty Advisor), Benjamin Aiken (Undergraduate), Katie Boyd (Undergraduate), Jake DeVol (Undergraduate), Evan Lyon (Undergraduate), Alexandria Rohrs (Undergraduate), Sarah S. Stone (Undergraduate), Elizabeth Sultan (Undergraduate), Tristan Williams (Undergraduate), and Sawyer C. Williams (Undergraduate)

Soil organic matter (SOM) is a fundamental characteristic to understanding a soil's ability to support plant growth. Its persistence, maintenance, and regeneration is of utmost importance in agricultural soil management. Conventional tilling practices expose more soil surface to rapid oxidation and subsequent SOM loss. At the same time there are other whole-field practices such as no-till and fallow that may not only minimize loss, but increase SOM storage. There is then a potential two-fold benefit of increasing, or maintaining, yields with few inputs as well as acting as a net sink rather than source of CO2 to the atmosphere and subsequent climate effects.

Our study seeks to seeks to establish benchmark values of SOM in a long-term study of how it responds to conventional agricultural practice, conservation reserve program (CRP) practices, and native prairie restoration. In the October - November 2022 we sampled soil from thirty randomly selected locations from each of these three field types in Greene County, Ohio. At each point we collected a core to estimate bulk density along with three cores that were composited. All cores were divided into 0 -5, 5 - 15, and 15 - 30cm depths. Bulk density values allow for whole field (volumetric) rather than point estimates and will serve as the basis to estimate total SOM and carbon storage. Soils will be sieved to remove all coarse material (> 2.0 mm). The remaining fine soil will be subsampled and SOM estimated from loss-on-ignition technique (400 degrees C for 4 hours). We plan to monitor these and additional sites into the future to understand how these management practices influence SOM.

Distribution of Adena-Hopewell Mounds and Earthworks in the Ohio River Valley

by Gretchen Nichols (Undergraduate)

From around 1,500 B.C. to A.D. 400, the Ohio River Valley was inhabited by Native American peoples of the Adena-Hopewell cultural complexes. These peoples built many earthen mounds and various other earthworks across the landscape, many of which can still be seen to this day. This project aims to use ArcGIS to display the distribution of these mounds and earthworks as well as some of the physiographic features of the land surrounding them. The spatial data for this project will be compiled from the State Historic Preservation Office inventory data, the United States Geological Survey, the Ohio Department of Natural Resources, the Environmental Protection Agency, Web Soil Survey, and other governmental resources. By visually representing physiographic features such as elevation, slope, glacial history, geological resources, and more, the relationship these features have with the location of Adena-Hopewell earthworks can be observed and may provide insight into how those who previously inhabited the land around the Ohio River Valley responded and related to it.

A Potential Biocorrelation of the Morisson, Lourinha, and Tendaguru Formations

by Jonathan Maxwell (Undergraduate)

The dinosaurs of the Lourinha and Tendaguru Formations have long been of interest to paleontologists due to their unusually high degree of similarity to the famously charismatic dinosaurs of the Morrison Formation. These formations famously have species of Allosaurus, Torvosaurus, Ceratosaurus, and Dryosaurus, as well as genus from the Diplodocids, Brachiosaurids, and Stegosaurs. This project will attempt to use data from the Paleobiology Database and the PaleoMap PaleoAtlas to construct a map of these three formations using ArcGIS and GPlates, both in their modern context, and as the continents are believed to have been arranged at the time of the Jurassic. Their fossil sites can be coordinated to their ancient counterparts to assist in determining how closely related these formations are and if inferences can be made about one by comparison to the other two.

K-feldspar Sand Grain Rounding in Aeolian and Subaqueous Transportation

by Elizabeth Sultan (Undergraduate) and Emma Henze (Undergraduate)

This project aims to compare the rounding of K-feldspar grains in aeolian and subaqueous conditions. It is hypothesized that K-feldspar grains in the subaqueous environment will be cushioned enough to prevent the rounding seen in aeolian environments. Our experiment is being conducted by use of aeolian and subaqueous simulations created by Calvin Anderson for comparing muscovite flakes in the different environments. We expect to see the aeolian environment produce rounded grains within a few weeks with the aqueous environment taking months at least to produce fully rounded grains. The results of this project will give scientists another distinguishing characteristic that can be used in the field to identify the depositional environment of sandstones.

Geologic Analysis of Ice Age Model Results

by Elizabeth Sultan (Undergraduate)

The purpose of this research project is to compare the output data from a 393-year ModelE2.1.2 run of an ice age simulation to the geologic record of the ice age. The ice age model was based on Michael Oard’s hypothesis of how the Ice Age could rapidly develop in the post-flood environment of an aerosol filled atmosphere and warm oceans. The results of this project are expected to show positive correlation between the output and the geological data as well as point out the areas where further research is needed.

Crash-Testing Cladistics

by Johnathan Maxwell (Undergraduate)

The practice of categorizing organisms is a practice as old, or perhaps older than the practice of biology itself. There have been many ways of constructing trees of life throughout the history of this science, but many of the recent methods have involved statistical predictions using computer programs that rely less on the actual human input. This project set out to test two of these methods for efficacy. The programs/methods chosen were Mesquite and MrBayes for evolutionary cladistics and a creationist model called baramninology which uses the program BARCLAY. Each of these programs were fed three different sets of data: one with a known evolutionary history (dog breeds), and two from heavily abstracted outside sources with no known evolutionary history. This allows conclusions to be drawn about how and why these methods produce the results they do.

Poster

Discerning Interaction Levels of Mutated Protocadherin-19 with Neuronal Cadherin

by Sharron Cooper (Faculty Advisor), Allegra Fife (Undergraduate), Abigail Hall (Undergraduate), Abby Jones (Undergraduate), Abby Naas (Undergraduate), Emily Wachter (Undergraduate)

Protocadherin-19 clustering epilepsy (PCDH19-CE) is a genetic neurodevelopmental disorder that causes febrile seizures and, in some cases, intellectual impairment in young girls. It is so named because it is caused by mutations in PCDH19. We studied the interaction between PCDH19 and neural cadherin (NCAD), which is vital for neurulation and affects the adhesive properties of PCDH19. The purpose of our research is to gain further understanding of the relationship between PCDH19 and NCAD to better understand PCDH19-related epilepsy. This will hopefully help further treatment of epilepsy patients’ symptoms. We studied four specific mutations coming from two different categories: the Hydrophobic Patch (mutations Y448R and L652P) and the EC6 Mutation Cluster (mutations E592R and E599R). In this study, we used site-directed mutagenesis to introduce the mutations into the wild-type PCDH19 and used a strain of E. coli to replicate the plasmid DNA. We then isolated and purified the plasmid DNA and transfected it into HeLa cells. Finally, co-immunoprecipitation and western blotting were performed to determine whether the mutated PCDH19 interacted with NCAD. The co-immunoprecipitation data showed that none of the mutations we tested appeared to decrease the interaction between PCDH19 and NCAD. However, the data for Y448R and L652P is less clear and therefore warrants further confirmation by replicating the experiment. Overall, the data suggests that neither the EC6 mutation cluster nor the hydrophobic patch are critical to the interaction between PCDH19 and NCAD, but instead may mediate other functions for PCDH19.

Poster

Differences in Germination Time of Soybean (Glycine max(L.) Merr.) Cultivar

by Robert L. Paris (Faculty), Alexandria Rohrs (Undergraduate), Luke Gustafson (Undergraduate), David Armistead (Undergraduate), Olivia Estep (Undergraduate), Zachary Roberts; and Benjamin Vincent (Undergraduate)

The variation of germination rates among individual seeds of a soybean (Glycine max (L.) Merr.) cultivar is not well documented. Assessing whether decreased germination time is a genetic factor that could be selected, has important economic impacts since seed yield in soybean is directly related to the number of days the crop grows. In order to determine the rate at which soybean seed germinate on an individual-seed basis, an experiment was designed whereby sets of ten soybean seed were rolled up in 35 cm lengths of wet paper towels and placed in plastic tubs to monitor germination rates. Two temperature treatments were used, 22°C (room temperature) 10°C (cool spring soil). The room temperature seed was checked at 24 hours after rolling in the wet paper towel, and those seed with the radical emerging or preparing to emerge were considered to be in the early-germination class. They were immediately removed and planted in 3 inch plastic pots with a soilless potting media and placed under grow lights. At 48 hours seed rolls were checked again, and seed with the radical emerging or preparing to emerge were considered to be in the intermediate-germination class, and were discarded. Seed was checked a final time at 72 hours and any seed with the radical emerging or preparing to emerge were considered to be in the late-germination class. They were immediately removed and planted in 3 inch plastic pots with a soilless potting media and placed under grow lights. The seed lot germinated under cool conditions was treated in the same way, except check times were 72 hours for the early-germination class, 120 hours for the intermediate-germination class, and 168 hours for the late-germination class. The germinated seed, of both early and late germination types, will be grown to maturity, and seed collected for germination analysis. Data analysis will be conducted to determine if there is a correlation between initial seed germination time and F₁ seed germination time. If a correlation is found, this would be an important step in identifying a genetic factor that could contribute to increased seed yield in commercial soybean production.

Poster

Soil CO2 efflux varies in response to soil series and prairie restoration

In 1999, faculty from Cedarville University seeded a field with native prairie grass species. Previously the land had been under row-crops, but drinking water well-head protections limited the application of fertilizer and pesticides such that the fields had been taken out of production. This project was maintained with regular disturbances such as mowing and prescribed fire to encourage the establishment of the desired species. In the interim the 20-acre site has developed to support the dominant species typical of a tallgrass prairie.

The goal of our study was to assess if this restoration effort has a significant (alpha = 0.05) impact on soil CO2 efflux. To determine this we measured sol CO2 efflux at 30 randomly distributed points in both the restored prairie and a nearby agricultural field. Using a LiCor 6400 infrared gas analyzer we found significantly (p < 0.0001) greater soil CO2 efflux in the restored prairie as compared to the agricultural field. We also found a significant effect (p = 0.002) of soil series. We plan to further expand our statistical analysis to determine the role of covariates (soil temperature and chamber humidity) while a related study will investigate the potential contribution of soil organic matter variability at these locations.

Poster