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Effects Of Red Light Intensity On Cultivation & Oxygen Production In Arthrospira Plantensis, Abigail Roberts Dec 2022

Effects Of Red Light Intensity On Cultivation & Oxygen Production In Arthrospira Plantensis, Abigail Roberts

Honors Theses

Maintaining life sustaining resources during long-term space travel has encouraged scientists to turn their attention to the potential benefits of a cyanobacteria named Arthrospira platensis, commonly known as Spirulina algae. This experiment measures the oxygen production and cell population growth of two structurally different Spirulina cultures under two different levels of red light intensities, 8 µmol/m 2Js (high); 3 µmol/m2/s (low). The cell population, oxygen produced, and oxygen produced per cell measurements were observed and recorded at three 24 hour intervals. It was found there was not a significant difference between high and low light intensities when considering the cell …


A Small Stem Assay For Chestnut Blight Resistance In Hybrid American Chestnut Trees, Evelyn Odle May 2022

A Small Stem Assay For Chestnut Blight Resistance In Hybrid American Chestnut Trees, Evelyn Odle

Honors Theses

Cryphonectria parasitica (Murr.) Barr is the causal agent for the chestnut blight disease, which was brought to North America in the late 19th century on nursery stock from Japan (Anagnostakis 1987). A pandemic of chestnut blight lasted for the next half century, nearly wiping out all American chestnut trees (Castanea dentata Borkh.). Restoration works to restoring the American chestnut to its native range in North America’s canopy has been going on for the past century. The American Chestnut Foundation has strived to breed a resistant American chestnut by backcross breeding with Chinese species (C. mollissima Blume) since the 1980s. The …


The Effect Of Clay On The Inhibitory Effect Of Mustard Seed Meal On Velvetleaf Seedling Growth, Heeyun Oh Apr 2022

The Effect Of Clay On The Inhibitory Effect Of Mustard Seed Meal On Velvetleaf Seedling Growth, Heeyun Oh

Honors Theses

Mustard seed meal (MSM) has been studied as a biofumigant in suppressing weed growth in an organic-friendly way. Previous studies have shown that MSM in the presence of elevated sand content was highly effective in suppressing the germination of velvetleaf seeds, and that as clay/silt in sand content increased, MSM effectiveness decreased in suppressing seed germination. Based on these results, it was postulated that clay may have effects on MSM by inhibiting this biofumigant from suppressing weed growth. Two different types of pure clay--kaolin and montmorillonite--were selected with their increasing concentrations. Low concentrations of clay do not seem to influence …


A Rapid Species-Specific Diagnostic Assay For Xylaria Necrophora, The Pathogen Behind Taproot Decline Of Soybean In The Southern United States, Sophie Baron Sheffield Apr 2022

A Rapid Species-Specific Diagnostic Assay For Xylaria Necrophora, The Pathogen Behind Taproot Decline Of Soybean In The Southern United States, Sophie Baron Sheffield

Honors Theses

No abstract provided.


Seabem: An Artificial Intelligence Powered Web Application To Predict Cover Crop Biomass, Aime Christian Tuyishime, Andrea Basche Mar 2022

Seabem: An Artificial Intelligence Powered Web Application To Predict Cover Crop Biomass, Aime Christian Tuyishime, Andrea Basche

Honors Theses

SEABEM, the Stacked Ensemble Algorithms Biomass Estimator Model, is a web application with a stacked ensemble of Machine Learning (ML) algorithms running on the backend to predict cover crop biomass for locations in Sub-Saharan. The SEABEM model was developed using a previously developed database of crop growth and yield that included site characteristics such as latitude, longitude, soil texture (sand, silt, and clay percentages), temperature, and precipitation. The goal of SEABEM is to provide global farmers, mainly small-scale African farmers, the knowledge they need before practicing and benefiting from cover crops while avoiding the expensive and time-consuming operations that come …


Source Of Off-Type Frequencies In Winter Wheat Varieties, Michaela Benes Mar 2022

Source Of Off-Type Frequencies In Winter Wheat Varieties, Michaela Benes

Honors Theses

The enzyme polyphenol oxidase (PPO) is undesirable in most wheat products due to the discoloration it causes. Purifying wheat varieties through selective breeding is the best way at getting rid of PPO in a variety. The variety NW15443 was planted in both a field in McCook, NE, and in a greenhouse in Lincoln, NE. Individual heads were snapped from the field and the greenhouse seed was harvested in bulk. After completing a PPO test of the seed, it was determined that the percentages of off-type frequencies from the field seed and the greenhouse seed were 11% and 3.6%, respectively. Using …


Influence Of Fertilizer Rate On Swollen Stem Formation (“Bulbing”) And Vitamin C Content In Different Kohlrabi Cultivars, Mark Iradukunda, Paul E. Read Mar 2022

Influence Of Fertilizer Rate On Swollen Stem Formation (“Bulbing”) And Vitamin C Content In Different Kohlrabi Cultivars, Mark Iradukunda, Paul E. Read

Honors Theses

Kohlrabi (Brassica oleracea Gongylodes Group) is a vegetable crop found in the Brassicaceae, and it is rich in antioxidants such as vitamin C. Vitamin C helps in oxidative damage repair and strengthens the immune system, so exploring vitamin C sources may contribute to improving human health. The objective of this study was to determine the effect of different fertilizer rates on kohlrabi yield, in terms of the swollen stem and the vitamin C content, and if those effects are similar in different kohlrabi cultivars. In this greenhouse study, we fertilized four potted kohlrabi cultivars with a common water-soluble greenhouse fertilizer …


Modeling Jadera Haematoloma’S Phenotypic Variation In The Context Of Its Developmental Plasticity, Michael C. Yorsz Jan 2022

Modeling Jadera Haematoloma’S Phenotypic Variation In The Context Of Its Developmental Plasticity, Michael C. Yorsz

Honors Theses

Phenotypic plasticity is the ability of an organism to integrate information from environmental cues to inform the development of its phenotype and remains understudied in biology. Models of plasticity are needed because evolution in the presence of plasticity is poorly understood. Jadera haematoloma, a hemimetabolous true bug, is an excellent animal model of plasticity, exhibiting a non-linear plastic response to juvenile nutrition that biases adult development into groups with differences in flight capability, wing shape, and fecundity. However, there is a lack of literature consensus regarding the range of developmental outcomes in the species. Some publications report the presence …


Biochar: Properties And Potential Benefits For Agricultural Soil In Rwanda, Andromede Uwase Jan 2022

Biochar: Properties And Potential Benefits For Agricultural Soil In Rwanda, Andromede Uwase

Honors Theses

Physical and chemical soil degradation is becoming a major challenge for agricultural productivity in Rwanda, which is the most important part of the country’s economy. The wide spreading soil degradation in Rwanda is mainly a result of naturally poor soils coupled with unsustainable soil management leading to, for example, accelerated soil erosion, acidification, nutrient loss, compaction, and to decreasing yields. Biochar, as an end product of pyrolysis of biomass in the absence of oxygen, has been proposed as a soil amendment in remediation strategies because of its positive effects on soil productivity relevant parameters such as soil pH, structure, nutrient …


Targeting Transgenic Proteins To The Mitochondria In Plants, Susan Qudus, Jeffrey P. Mower Jan 2022

Targeting Transgenic Proteins To The Mitochondria In Plants, Susan Qudus, Jeffrey P. Mower

Honors Theses

Cytoplasmic male sterility (CMS) in plants can convert an individual into female through sterilization of the male reproductive parts, creating an inability to produce functional pollen. In nature, this is advantageous for genetic diversity and producing progeny with unique genes that may be beneficial in evolution. For agriculture, this method is preferential for selection of desirable traits in crops when cross breeding. CMS is typically caused by genes in the mitochondrial DNA (mtDNA), such as novel open reading frames (ORFs) that form after imperfect repair of double-stranded breaks in the mtDNA. Specific CMS genes vary among various plant species. It …