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Full-Text Articles in Life Sciences
Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan Mcpherson
Mycorrhizae In Maize (Zea Mays L.) Cropping Systems Respond Differently To Nitrogen Fertilization Under Increasing Crop Rotational Diversity, Morgan Mcpherson
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Arbuscular mycorrhizal fungi (AMF) remain a vital obligate symbiont of nearly all plants. It is well established that the symbiosis between AMF and host plant improves plant nutrient acquisition, alleviates abiotic and biotic environmental stressors, defends against plant pathogens, and contributes to overall plant fitness and productivity through modification of the soil habitat. Modifications include increased soil aggregation and stability, carbon sequestration through provision of fungal wall precursors to soil organic matter (SOM) formation, and enhanced nutrient cycling in the mycorrhizosphere. The goal of this dissertation was to assess how AMF respond to nitrogen (N) fertilization regimes in maize cropping …
Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio
Benchmarking On-Farm Maize Nitrogen Balance In The Western U.S. Corn Belt, Fatima Amor Tenorio
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
A nitrogen (N) balance, calculated as the difference between N inputs and grain-N removal, provides an estimate of the potential N losses. We used N balance with other N-related metrics (partial factor productivity for N inputs, and yield-scaled N balance), to benchmark maize yields in relation with N input use in the US Corn Belt. We first used experimental data on grain-N concentration (GNC) to assess variation in this parameter due to biophysical and management factors. Subsequently, we used N balance and N-related metrics to benchmark yields in relation with N inputs in irrigated and rainfed fields in Nebraska using …
New Approaches To Use Genomics, Field Traits, And High-Throughput Phenotyping For Gene Discovery In Maize (Zea Mays), Zhikai Liang
New Approaches To Use Genomics, Field Traits, And High-Throughput Phenotyping For Gene Discovery In Maize (Zea Mays), Zhikai Liang
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Maize is one of major crop species over the world. With lots of genetic resources and genomic tools, maize also serves as a model species to understand genetic diversity, facilitate the development of trait extraction algorithms and map candidate functional genes. Since the first version of widely used B73 reference genome was released, independent research groups in the maize community propagated seeds themselves for further research purposes. However, unexpected or occasional contamination may happen during this process. The first study in this thesis used public RNA-seq data of B73 from 27 research groups across three countries for calling single nucleotide …
Biochemical And Proteomic Profiling Of Maize Endosperm Texture And Protein Quality, Kyla J. Morton
Biochemical And Proteomic Profiling Of Maize Endosperm Texture And Protein Quality, Kyla J. Morton
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The research described herein, focuses on the biochemical and proteomic analysis of the maize endosperm and what influences kernel texture. Quality Protein Maize (QPM) is a hard endosperm version of the high-lysine opaque2 (o2) mutant but the genes involved in modifying the soft o2 endosperm are unknown. Pyrophosphate (PPi)-dependent fructose 6-phosphate 1-phosphotransferase (PFP) catalyzes the ATP-independent conversion of fructose 6-phosphate to fructose 1, 6-bisphosphate in glycolysis. We found a large increase in transcript and protein levels of the alpha regulatory subunit of PFP (PFPα) in QPM endosperm. In vitro enzyme assays show a significant increase in forward PFP …
Carbohydrate Metabolism And The Trehalose Biosynthetic Pathway In Maize Kernels Grown In Vitro Under Sucrose Starvation Stress, Samuel W. Bledsoe
Carbohydrate Metabolism And The Trehalose Biosynthetic Pathway In Maize Kernels Grown In Vitro Under Sucrose Starvation Stress, Samuel W. Bledsoe
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Drought is an increasing issue that many farmers encounter especially in hot arid climates with little rainfall. High temperatures and inadequate rainfall at certain stages in crop development can have disastrous consequences to yield. In maize, drought occurring near or during the flowering stage often causes significant kernel abortion that greatly impacts potential yield. The trehalose biosynthetic pathway has recently been found to be important in plant metabolism in response to stress in higher order plants. Trehalose is currently known throughout the plant and animal kingdoms as an osmoprotectant, high energy fuel source, structural component, and involved in pathogen response. …
Functional Genomics Of Maize Endosperm Maturation And Protein Quality, Lingling Yuan
Functional Genomics Of Maize Endosperm Maturation And Protein Quality, Lingling Yuan
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Maize is one of the most important cereal crops and widely cultivated throughout the world. The study on maize kernel development including protein quality improvement is essential for removing dietary protein deficiency because of the lack of essential amino acids, especially lysine and tryptophan, in maize kernel. Quality Protein Maize (QPM) is a hard kernel variant of the high-lysine mutant, opaque-2. We created opaque QPM variants to identify opaque-2 modifier genes and to investigate deletion mutagenesis combined with Illumina sequencing as a maize functional genomics tool. A K0326Y-QPM deletion mutant, line 107, was null for the 27- and 50-kD …
Estimating Maize Grain Yield From Crop Biophysical Parameters Using Remote Sensing, Noemi Guindin-Garcia
Estimating Maize Grain Yield From Crop Biophysical Parameters Using Remote Sensing, Noemi Guindin-Garcia
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
The overall objective of this investigation was to develop a robust technique to predict maize (Zea mays L.) grain yield that could be applied at a regional level using remote sensing with or without a simple crop growth simulation model. This study evaluated capabilities and limitations of the Moderate Resolution Imaging Spectroradiometer (MODIS) Vegetation Index 250-m and MODIS surface reflectance 500-m products to track and retrieve information over maize fields. Results demonstrated the feasibility of using MODIS data to estimate maize green leaf area index (LAIg). Estimates of maize LAIg obtained from Wide Dynamic Range Vegetation …
Xenia Effects On Quality Of Maize Female Inbred In Production Of Hybrid Seeds, Leandro Castañeda
Xenia Effects On Quality Of Maize Female Inbred In Production Of Hybrid Seeds, Leandro Castañeda
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
In Maize (Zea maize L.), cost of hybrid seed production is directly related to the yield and quality of seed obtained per hectare of female parent. It is also important to consider the effects that a male parent can exert on the development of hybrid seed in the female parent. This effect is known as xenia. The objectives of this study were to evaluate xenia effects on 1) yield as 80K units, 2) germination of the hybrid seed and 3) susceptibility of the hybrid seed to mechanical damage. One female inbred and four male inbred lines were selected from a …
Yield Potential And Resource-Use Efficiency Of Maize Systems In The Western U.S. Corn Belt, Patricio Grassini
Yield Potential And Resource-Use Efficiency Of Maize Systems In The Western U.S. Corn Belt, Patricio Grassini
Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research
Maize demand for food, livestock feed, and biofuel is expected to increase substantially. The Western U.S. Corn Belt accounts for 23% of U.S. maize production, and irrigated maize accounts for 43 and 58% of maize land area and total production, respectively, in this region. The most sensitive parameters (yield potential [YP], water-limited yield potential [YP-W], yield gap between actual yield and YP, and resource-use efficiency) governing performance of maize systems in the region are lacking. A simulation model was used to quantify YP under irrigated and rainfed conditions based on weather data, soil properties, and crop management at 18 locations. …