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Full-Text Articles in Life Sciences
Effects Of Temperature And Pollinator Availability On Plant Reproductive Success In The Indiana Spring Ephemeral Community, Asya Robertshaw
Effects Of Temperature And Pollinator Availability On Plant Reproductive Success In The Indiana Spring Ephemeral Community, Asya Robertshaw
Open Access Dissertations
Temperature is a key driver of phenology in both plants and insects, and even small changes in temperature can impact the reproductive success of insect-pollinated plants by influencing access to pollinator services. While it is well-established that temperature variation directly impacts the flowering phenology of many plant species, the mechanisms by which it ultimately influences seed production via the pollinator community are not well understood. Climate change has the potential to disrupt the temporal synchrony between plants and their primary pollinators, especially if the two rely on different seasonal cues for the timing of their life history events. If the …
Genetic, Agronomic And Compositional Characterization Of Brown Midrib Sweet Sorghum Lignocellulosic Biomass For Ethanol Production, Luis A. Rivera Burgos
Genetic, Agronomic And Compositional Characterization Of Brown Midrib Sweet Sorghum Lignocellulosic Biomass For Ethanol Production, Luis A. Rivera Burgos
Open Access Dissertations
Sorghum is a promising bioenergy crop due to its unique phenotypic and genotypic attributes. Quality (low lignin and high stem sugar concentration) and quantity (biomass yield, plant height, plant maturity, etc.) biomass traits are key contributors to ethanol yield and production. In this study, a 236 sorghum recombinant inbred line (RIL) population was subjected to genetic, agronomic and compositional characterization for ethanol yield and production. We found that the sweet mutation enhances biomass quantity traits in the RILs which translates to higher ethanol production and biomass quality which improves ethanol yield. The variance components showed from moderate to high heritability …
Cover Crop And No-Till Effects On Soil Health Properties In Indiana, Sara Alford
Cover Crop And No-Till Effects On Soil Health Properties In Indiana, Sara Alford
Open Access Theses
A growing concern of soil health and long-term sustainability has increased interest in no-till and cover crops in the Midwest. Some of the challenges with no-till in the Midwest can be higher soil moisture and lower soil temperatures at cash crop planting in the spring, planter adjustment issues, and lack of immediate economic benefit. Cover crops also have some of the same issues along with extra cost of seed and termination, mismanagement of cover crops, and lack of knowledge on the benefits and costs. This project was begun in order to quantify the effects of no-till and cover crops on …
Genetic Analysis Of Tocochromanol Variation In Maize Using High-Density Linkage Mapping, Megan E. Fenton
Genetic Analysis Of Tocochromanol Variation In Maize Using High-Density Linkage Mapping, Megan E. Fenton
Open Access Theses
Vitamin E is an essential nutrient in the human diet and refers to eight distinct compounds that are collectively known as tocochromanols. Tocochromanols are grouped into two classes: tocotrienols and tocopherols. Tocochromanols are the major lipid-soluble antioxidants in maize (Zea mays L.) grain. Enhancing the tocochromanol content of maize derived foods through plant breeding has important nutritional and health implications. Chapter one is a literature review that provides a foundational understanding of the biosynthesis, function and genetic control of tocochromanols in plants, with specific attention to maize (Zea mays L.). Upon this foundation two research objectives were developed that work …
Eco-Evolutionary Factors Drive Herbivore-Induced Plant Volatiles, Which Intercept Plant Defense, Elizabeth K. Rowen
Eco-Evolutionary Factors Drive Herbivore-Induced Plant Volatiles, Which Intercept Plant Defense, Elizabeth K. Rowen
Open Access Theses
Herbivore-induced plant volatiles (HIPVs) mediate a wide variety of interactions in ecosystems. However, many volatile compounds are found across plant taxa, and some are exploited to attract natural enemies for biological control. Subtle changes in HIPV blends can produce profound changes in the behavior of predators, parasitoids and herbivores, and may also alter the defensive processes of neighboring plants. I investigated different ecological and evolutionary factors to understand how plant volatile emissions are affected by feeding guild, herbivore diet breadth and domestication. I meta-analyzed 109 studies and found that specialists induce more total volatiles than generalists. Domesticated species have stronger …
Growth Parameters Of 'Golden Delicious' Apple Trees (Malus X Domestica Borkh), Biying Shi
Growth Parameters Of 'Golden Delicious' Apple Trees (Malus X Domestica Borkh), Biying Shi
Open Access Theses
High yield and high quality of tree fruit result from appropriate orchard design and management practices. This requires an accurate knowledge of vegetative growth, branching, and flowering processes of fruit trees. Tree development knowledge is the fundamental information necessary to build functional-structural tree models, which have various applications in agriculture. To build such models, information is needed on the distributions of growth parameters, not merely means as are often reported. The objective of this study was to quantitatively analyze shoot development and examine the correlations between fruit quality and light distribution in apple trees. This study was conducted in 2014, …
Profiling Gene Expression During Early Gametophyte Development And Sex Determination In Ceratopteris Richardii, Nadia Atallah
Profiling Gene Expression During Early Gametophyte Development And Sex Determination In Ceratopteris Richardii, Nadia Atallah
Open Access Dissertations
In the fern Ceratopteris richardii, every spore has the potential to develop as either a male or hermaphroditic gametophyte. Gametophyte sex is determined by a GA-like pheromone (ACE) that is secreted by hermaphrodites approximately 6 days after spore inoculation and induces male development in other juvenile gametophytes. Our goal is to better understand the genetic and molecular mechanisms involved in sex determination and to identify sex determination genes in Ceratopteris. RNA-Seq was used to create de novotranscriptome assemblies from gametophytes grown, with or without ACE, during the time that their sex is determined, and from male gametophytes in early …
Genetic Analysis Of Nitrogen Remobilization And Kernel Compositon In Zea Mays L. And Sorghum Bicolor (L.) Moench, Raymond S Lindsey
Genetic Analysis Of Nitrogen Remobilization And Kernel Compositon In Zea Mays L. And Sorghum Bicolor (L.) Moench, Raymond S Lindsey
Open Access Dissertations
Genetic Analysis of Nitrogen Remobilization and Kernel Composition in Zea Mays L. and Sorghum Bicolor (L.) Moench. Major Professor: Mitchell Tuinstra. Modern maize (Zea mays L.) production relies heavily on nitrogen fertilization for high productivity. Over-application of nitrogen fertilizers in cropping systems can have detrimental economic and environmental effects. For this reason, improving Nitrogen Use Efficiency (NUE) is a major goal of breeders and producers. Nitrogen Utilization Efficiency (NUtE) is one component of NUE, and the most important component under N-limited conditions. In this study we examined the genetic controls of the timing and preferential canopy position of leaf N …
Utilization Of Tall Wheatgrass Translocation Lines To Improve Fusarium Head Blight Resistance In Wheat, Xiangye Xiao
Utilization Of Tall Wheatgrass Translocation Lines To Improve Fusarium Head Blight Resistance In Wheat, Xiangye Xiao
Open Access Dissertations
Fusarium head blight (FHB) and leaf rust (LR) are two major fungal pathogens threatening the wheat crop, consequently identifying resistance genes from various sources is always of importance to wheat breeders. Type II FHB resistance in wheat has been improved by introgressing QTL from landraces and wild species. The present study was undertaken to (1) combine two different type II FHB resistance QTL in the backgrounds of six adapted wheat lines (2) improve the map resolution of Qfhs.pur-7EL.^ In the first objective, the FHB resistance gene Fhb1 originated in a Chinese wheat cultivar and is located on wheat chromosome …
Application And Implications Of Rule-Based Pruning Of Apple Trees, Jacob B. Franzen
Application And Implications Of Rule-Based Pruning Of Apple Trees, Jacob B. Franzen
Open Access Theses
Labor is one of the largest operating costs associated with tree fruit production in the United States. Pruning and harvest can easily eclipse over a quarter of an orchard's operating budget. Additionally, labor sources are becoming increasingly difficult to find while worker pay keeps going up. As a result, it appears that labor costs will continue to rise for the foreseeable future. Work on developing mechanized alternatives to pruning is seen as one of the key areas to reduce an orchard's dependence on human labor. The objective of this study was to test a set of simplified pruning rules (RUL), …
Framework For Functional Tree Simulation Applied To 'Golden Delicious' Apple Trees, Marek Fiser
Framework For Functional Tree Simulation Applied To 'Golden Delicious' Apple Trees, Marek Fiser
Open Access Theses
This research aims to develop a framework to model realistic and functional trees. Our modular framework is easily controllable and extensible by the user. The framework provides powerful features such as per-leaf light simulation and a source-sink based resources transport model. Our novel 3D reconstruction algorithm generates realistic tree models with a good 3D polygon topology. ^ The second part of this research is a functional model of a Golden Delicious apple tree. We use our simulation framework and data collected in Purdue Meigs farm over the year 2014 to create a realistic data-driven model. The model reacts on temperature …