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Full-Text Articles in Life Sciences

Genome-Wide Identification And Analysis Of Heterotic Loci In Three Maize Hybrids, Hongjun Liu, Qin Wang, Mengjiao Chen, Yahui Ding, Xuerong Yang, Jie Liu, Xiaohan Li, Congcong Zhou, Qilin Tian, Yiqi Lu, Danlin Fan, Junpeng Shi, Lin Zhang, Congbin Kang, Mingfei Mingfei Sun, Fangyuan Li, Yujian Wu, Yongzhong Zhang, Baoshen Liu, Xiang Yu Zhao, Qi Feng, Jinliang Yang, Bin Han, Jinsheng Lai, Xian Sheng Zhang, Xuehui Huang Jan 2020

Genome-Wide Identification And Analysis Of Heterotic Loci In Three Maize Hybrids, Hongjun Liu, Qin Wang, Mengjiao Chen, Yahui Ding, Xuerong Yang, Jie Liu, Xiaohan Li, Congcong Zhou, Qilin Tian, Yiqi Lu, Danlin Fan, Junpeng Shi, Lin Zhang, Congbin Kang, Mingfei Mingfei Sun, Fangyuan Li, Yujian Wu, Yongzhong Zhang, Baoshen Liu, Xiang Yu Zhao, Qi Feng, Jinliang Yang, Bin Han, Jinsheng Lai, Xian Sheng Zhang, Xuehui Huang

Agronomy & Horticulture -- Faculty Publications

Heterosis, or hybrid vigour, is a predominant phenomenon in plant genetics, serving as the basis of crop hybrid breeding, but the causative loci and genes underlying heterosis remain unclear in many crops. Here, we present a large-scale genetic analysis using 5360 offsprings from three elite maize hybrids, which identifies 628 loci underlying 19 yield-related traits with relatively high mapping resolutions. Heterotic pattern investigations of the 628 loci show that numerous loci, mostly with complete–incomplete dominance (the major one) or overdominance effects (the secondary one) for heterozygous genotypes and nearly equal proportion of advantageous alleles from both parental lines, are ...


Benchmarking Impact Of Nitrogen Inputs On Grain Yield And Environmental Performance Of Producer Fields In The Western Us Corn Belt, Fatima A.M. Tenorio, Eileen L. Mclellan, Alison J. Eagle, Kenneth G. Cassman, Daryl Andersen, Marie Krausnick, Russell Oaklund, John Thorburn, Patricio Grassini Jan 2020

Benchmarking Impact Of Nitrogen Inputs On Grain Yield And Environmental Performance Of Producer Fields In The Western Us Corn Belt, Fatima A.M. Tenorio, Eileen L. Mclellan, Alison J. Eagle, Kenneth G. Cassman, Daryl Andersen, Marie Krausnick, Russell Oaklund, John Thorburn, Patricio Grassini

Agronomy & Horticulture -- Faculty Publications

Benchmarking crop yields against nitrogen (N) input levels can help provide opportunities to improve N ferti-lizer efficiency and reduce N losses on maize in the US Corn Belt by identifying fields most likely to benefit from improved N management practices. Here, we evaluated a large producer database that includes field-level data on yield and applied N inputs from 9280 irrigated and rainfed fields over a 7-year period (2009–2015) in Nebraska (USA). A spatial framework, based on technology extrapolation domains, was used to cluster each field into spatial units with similar climate and soil type that represent 1.3 million ...


New Approaches To Use Genomics, Field Traits, And High-Throughput Phenotyping For Gene Discovery In Maize (Zea Mays), Zhikai Liang Aug 2019

New Approaches To Use Genomics, Field Traits, And High-Throughput Phenotyping For Gene Discovery In Maize (Zea Mays), Zhikai Liang

Theses, Dissertations, and Student Research in Agronomy and Horticulture

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 ...


Validation Of Candidate Loci For Maize Regrowability And Selection Of Near Isogenic Lines For The Loci, Tajbir Raihan Jan 2019

Validation Of Candidate Loci For Maize Regrowability And Selection Of Near Isogenic Lines For The Loci, Tajbir Raihan

Electronic Theses and Dissertations

Developing perennial grain crops is an effective way for sustainable agriculture and it can be a tool for the betterment of the overall ecosystem. To understand how perenniality works in perennial species, we made a cross between Zea diploperennis and maize (Z. mays) inbred line B73. F1 hybrids produced from this cross were selfed to get the F2 population and later the F2 population underwent Genotyping-By- Sequencing (GBS) analysis. Based on the candidate loci identified on chromosome 2 and chromosome 7 from GBS, SNP-specific markers were developed from the candidate locus interval and used to genotype the F2 population. X2 ...


Grass-Specific Mechanisms Of Iron Uptake: Investigation Of Phytosiderophore Transporters And Discovery Of Novel Iron Deficiency Loci, David Chan Rodriguez Oct 2018

Grass-Specific Mechanisms Of Iron Uptake: Investigation Of Phytosiderophore Transporters And Discovery Of Novel Iron Deficiency Loci, David Chan Rodriguez

Doctoral Dissertations

Iron-deficiency anemia is one of the most prevalent forms of malnutrition worldwide, affecting 1.62 billion people, with the population in developing countries being the most affected. Iron is equally vital in plants to perform essential functions such as photosynthesis. Crop grasses form part of everyday human nutrition, contribute fundamentally to human caloric intake, and, in some parts of the world, are the primary source of food. Grasses acquire iron from the soil by secreting chelator molecules called phytosiderophores to solubilize iron, making it available to be transported by the Yellow Stripe1 (YS1) transporter.

In this dissertation, I studied aspects ...


Direct Production Of Dihydroxylated Sesquiterpenoids By A Maize Terpene Synthase, Jin Liang, Jiang Liu, Reid Brown, Meirong Jia, Ke Zhou, Reuben J. Peters, Qiang Wang Jun 2018

Direct Production Of Dihydroxylated Sesquiterpenoids By A Maize Terpene Synthase, Jin Liang, Jiang Liu, Reid Brown, Meirong Jia, Ke Zhou, Reuben J. Peters, Qiang Wang

Biochemistry, Biophysics and Molecular Biology Publications

The astounding structural and biological diversity of the large class of terpenoid natural products are imparted by both their complex hydrocarbon backbones and further elaboration by the addition of multiple hydroxyl groups, which provide both solubility and specific binding properties. While the role of terpene synthases in generating hydrocarbons with complex backbones is well known, these also are known to generate (singly) hydroxylated products by the addition of water prior to terminating deprotonation. Here a maize sesquiterpene synthase was unexpectedly found to generate dually hydroxylated products directly from (E,E)-farnesyl diphosphate, primarily eudesmane-2,11-diol, along with two closely related ...


Identification Of Quantitative Trait Loci For Leaf-Related Traits In An Ibm Syn10 Dh Maize Population Across Three Environments, Langlang Ma, Zhongrong Guan, Zhiteng Zhang, Xiaoxiang Zhang, Yanling Zhang, Chaoying Zou, Huanwei Peng, Guangtang Pan, Michael Lee, Yaou Shen, Thomas Lubberstedt Feb 2018

Identification Of Quantitative Trait Loci For Leaf-Related Traits In An Ibm Syn10 Dh Maize Population Across Three Environments, Langlang Ma, Zhongrong Guan, Zhiteng Zhang, Xiaoxiang Zhang, Yanling Zhang, Chaoying Zou, Huanwei Peng, Guangtang Pan, Michael Lee, Yaou Shen, Thomas Lubberstedt

Agronomy Publications

Leaf-related traits (leaf length, leaf width, leaf area and leaf angle) are very important for the yield of maize (Zea mays L) due to their influence on plant type. Therefore, it is necessary to identify quantitative trait loci (QTLs) for leaf-related traits. In this report, 221 doubled haploid lines (DHLs) of an IBM Syn10 DH population were provided for QTL mapping. In total, 54 QTLs were detected for leaf-related traits in single environments using a high-density genetic linkage map. Among them, only eight common QTLs were identified across two or three environments, and the common QTLs for the four traits ...


Profile Of Genetically Modified Plants Authorized In Mexico, Mayra Teresa Garcia Ruiz, Aaron N. Knapp, Hernan Garcia Ruiz Jan 2018

Profile Of Genetically Modified Plants Authorized In Mexico, Mayra Teresa Garcia Ruiz, Aaron N. Knapp, Hernan Garcia Ruiz

Papers in Plant Pathology

Mexico is a center of origin for several economically important plants including maize, cotton, and cocoa. Maize represents more than a food crop, has been declared a biological, cultural, agricultural and economic patrimony, and is linked to the national identity of Mexicans. In this review, we describe the historic and current use of genetically modified plants in Mexico and factors that contributed to the development of the biosafety regulation. We developed a database containing all permit applications received by the government to release genetically modified plants. A temporal and geographical analysis identified the plant species that have been authorized for ...


Conventional And Hyperspectral Time-Series Imaging Of Maize Lines Widely Used In Field Trials, Zhikai Liang, Piyush Pandey, Vincent Stoerger, Yuhang Xu, Yumou Qiu, Yufeng Ge, James C. Schnable Jan 2018

Conventional And Hyperspectral Time-Series Imaging Of Maize Lines Widely Used In Field Trials, Zhikai Liang, Piyush Pandey, Vincent Stoerger, Yuhang Xu, Yumou Qiu, Yufeng Ge, James C. Schnable

Faculty Publications from the Center for Plant Science Innovation

Background: Maize (Zea mays ssp. mays) is 1 of 3 crops, along with rice and wheat, responsible for more than one-half of all calories consumed around the world. Increasing the yield and stress tolerance of these crops is essential to meet the growing need for food. The cost and speed of plant phenotyping are currently the largest constraints on plant breeding efforts. Datasets linking new types of high-throughput phenotyping data collected from plants to the performance of the same genotypes under agronomic conditions across a wide range of environments are essential for developing new statistical approaches and computer vision–based ...


Maize Genomes To Fields: 2014 And 2015 Field Season Genotype, Phenotype, Environment, And Inbred Ear Image Datasets, Naser Alkhalifah, Darwin A. Campbell, Celeste M. Falcon, Jack M. Gardiner, Nathan D. Miller, Maria Cinta Romay, Ramona Walls, Renee Walton, Cheng-Ting Yeh, Martin Bohn, Jessica Bubert, Edward S. Buckler, Ignacio Ciampitti, Sherry Flint-Garcia, Michael A. Gore, Christopher Graham, Candice Hirsch, James B. Holland, David Hooker, Shawn Kaeppler, Joseph Knoll, Nick Lauter, Elizabeth C. Lee, Aaron Lorenz, Jonathan P. Lynch, Stephen P. Moose, Seth C. Murray, Rebecca Nelson, Torbert Rocheford, Oscar Rodriguez, James C. Schnable, Brian Scully, Margaret Smith, Nathan Springer, Peter Thomison, Mitchell Tuinstra, Randall J. Wisser, Wenwei Xu, David Ertl, Patrick S. Schnable, Natalia De Leon, Edgar P. Spalding, Jode Edwards, Carolyn J. Lawrence-Dill Jan 2018

Maize Genomes To Fields: 2014 And 2015 Field Season Genotype, Phenotype, Environment, And Inbred Ear Image Datasets, Naser Alkhalifah, Darwin A. Campbell, Celeste M. Falcon, Jack M. Gardiner, Nathan D. Miller, Maria Cinta Romay, Ramona Walls, Renee Walton, Cheng-Ting Yeh, Martin Bohn, Jessica Bubert, Edward S. Buckler, Ignacio Ciampitti, Sherry Flint-Garcia, Michael A. Gore, Christopher Graham, Candice Hirsch, James B. Holland, David Hooker, Shawn Kaeppler, Joseph Knoll, Nick Lauter, Elizabeth C. Lee, Aaron Lorenz, Jonathan P. Lynch, Stephen P. Moose, Seth C. Murray, Rebecca Nelson, Torbert Rocheford, Oscar Rodriguez, James C. Schnable, Brian Scully, Margaret Smith, Nathan Springer, Peter Thomison, Mitchell Tuinstra, Randall J. Wisser, Wenwei Xu, David Ertl, Patrick S. Schnable, Natalia De Leon, Edgar P. Spalding, Jode Edwards, Carolyn J. Lawrence-Dill

Agronomy & Horticulture -- Faculty Publications

Objectives: Crop improvement relies on analysis of phenotypic, genotypic, and environmental data. Given large, well-integrated, multi-year datasets, diverse queries can be made: Which lines perform best in hot, dry environments? Which alleles of specific genes are required for optimal performance in each environment? Such datasets also can be leveraged to predict cultivar performance, even in uncharacterized environments. The maize Genomes to Fields (G2F) Initiative is a multi-institutional organization of scientists working to generate and analyze such datasets from existing, publicly available inbred lines and hybrids. G2F’s genotype by environment project has released 2014 and 2015 datasets to the public ...


Mapping Rootable Depth And Root Zone Plant-Available Water Holding Capacity Of The Soil Of Sub-Saharan Africa, John G. B. Leenaars, Lieven Claessens, Gerard B. M. Heuvelink, Tom Hengl, Maria Ruiperez Gonzalez, Lenny G. J. Van Bussel, Nicolas Guilpart, Haishun Yang, Kenneth G. Cassman Jan 2018

Mapping Rootable Depth And Root Zone Plant-Available Water Holding Capacity Of The Soil Of Sub-Saharan Africa, John G. B. Leenaars, Lieven Claessens, Gerard B. M. Heuvelink, Tom Hengl, Maria Ruiperez Gonzalez, Lenny G. J. Van Bussel, Nicolas Guilpart, Haishun Yang, Kenneth G. Cassman

Agronomy & Horticulture -- Faculty Publications

In rainfed crop production, root zone plant-available water holding capacity (RZ-PAWHC) of the soil has a large influence on crop growth and the yield response to management inputs such as improved seeds and fertilisers. However, data are lacking for this parameter in sub-Saharan Africa (SSA). This study produced the first spatially explicit, coherent and complete maps of the rootable depth and RZ-PAWHC of soil in SSA. We compiled georeferenced data from 28,000 soil profiles from SSA, which were used as input for digital soil mapping (DSM) techniques to produce soil property maps of SSA. Based on these soil properties ...


Water Productivity Of Rainfed Maize And Wheat: A Local To Global Perspective, Juan I. Rattalino Edreira, Nicolas Guilpart, Victor Sadras, Kenneth G. Cassman, Martin K. Van Ittersum, Rene L.M. Schils, Patricio Grassini Jan 2018

Water Productivity Of Rainfed Maize And Wheat: A Local To Global Perspective, Juan I. Rattalino Edreira, Nicolas Guilpart, Victor Sadras, Kenneth G. Cassman, Martin K. Van Ittersum, Rene L.M. Schils, Patricio Grassini

Agronomy & Horticulture -- Faculty Publications

Water productivity (WP) is a robust benchmark for crop production in relation to available water supply across spatial scales. Quantifying water-limited potential (WPw) and actual on-farm (WPa) WP to estimate WP gaps is an essential first step to identify the most sensitive factors influencing production capacity with limited water supply. This study combines local weather, soil, and agronomic data, and crop modeling in a spatial framework to determine WPw and WPa at local and regional levels for rainfed cropping systems in 17 (maize) and 18 (wheat) major grain-producing countries representing a wide range of cropping systems, from intensive, highyield maize ...


Assessing Explanatory Factors For Variation In On-Farm Irrigation In Us Maize-Soybean Systems, Katherine E.B. Gibson, Haishun S. Yang, Trenton E. Franz, Dean E. Eisenhauer, John B. Gates, Paolo Nasta, Bhupinder S. Farmaha, Patricio Grassini Jan 2018

Assessing Explanatory Factors For Variation In On-Farm Irrigation In Us Maize-Soybean Systems, Katherine E.B. Gibson, Haishun S. Yang, Trenton E. Franz, Dean E. Eisenhauer, John B. Gates, Paolo Nasta, Bhupinder S. Farmaha, Patricio Grassini

Agronomy & Horticulture -- Faculty Publications

Irrigation exhibits large variation across producer fields, even within same region and year. A knowledge gap exists relative to factors that explain this variation, in part due to lack of availability of high-quality irrigation data from multiple field-years. This study assessed sources of variation in irrigation using a large database collected during 9 years (2005–2013) from ca. 1400 maize and soybean producer fields in Nebraska, central USA (total of 12,750 field-year observations). The study area is representative of ca. 4.5 million ha of irrigated land sown with maize and soybean. Influence of biophysical (weather, soil, and crop ...


Mapping Rootable Depth And Root Zone Plant-Available Water Holding Capacity Of The Soil Of Sub-Saharan Africa, Johan G. B. Leenaars, Lieven Claessens, Gerard B.M. Heuvelink, Tom Hengl, Maria Ruiperez Gonzalez, Lenny G.J. Van Bussel, Nicolas Guilpart, Haishun Yang, Kenneth G. Cassman Jan 2018

Mapping Rootable Depth And Root Zone Plant-Available Water Holding Capacity Of The Soil Of Sub-Saharan Africa, Johan G. B. Leenaars, Lieven Claessens, Gerard B.M. Heuvelink, Tom Hengl, Maria Ruiperez Gonzalez, Lenny G.J. Van Bussel, Nicolas Guilpart, Haishun Yang, Kenneth G. Cassman

Agronomy & Horticulture -- Faculty Publications

In rainfed crop production, root zone plant-available water holding capacity (RZ-PAWHC) of the soil has a large influence on crop growth and the yield response to management inputs such as improved seeds and fertilisers. However, data are lacking for this parameter in sub-Saharan Africa (SSA). This study produced the first spatially explicit, coherent and complete maps of the rootable depth and RZ-PAWHC of soil in SSA. We compiled georeferenced data from 28,000 soil profiles from SSA, which were used as input for digital soil mapping (DSM) techniques to produce soil property maps of SSA. Based on these soil properties ...


Identification Of Qtl Modifying The Activity Of The Tcb1-S Locus And Characterization And Sequencing Of Two Plutonium-Beryllium Induced Reduced Gametophyte Transmission Mutants In Maize, Merritt Bryer Burch Jan 2018

Identification Of Qtl Modifying The Activity Of The Tcb1-S Locus And Characterization And Sequencing Of Two Plutonium-Beryllium Induced Reduced Gametophyte Transmission Mutants In Maize, Merritt Bryer Burch

Electronic Theses and Dissertations

This thesis is split into two independent projects both involving the male gametophyte generation of maize. The first project looks at how pollen interacts with the female gametophyte to reduce its transmission in cross-incompatible reactions controlled by the unilateral cross-incompatibility system, teosinte crossing barrier 1. The second project explores two plutonium-beryllium induced male gametophyte mutants and attempts to uncover their genetic basis.

Identification of QTL Modifying the Activity of the Tcb1-s Locus
Teosinte crossing barrier 1 (Tcb1) is a unilateral cross-incompatibility system present in maize that provides a pre-zygotic pistil barrier to plants carrying Tcb1-s (strong allele) from pollen not ...


Uncovering Tasselsheath3. A Genomic And Phenotypic Analysis Of A Maize Floral Mutant., Thompson Zhang Oct 2017

Uncovering Tasselsheath3. A Genomic And Phenotypic Analysis Of A Maize Floral Mutant., Thompson Zhang

Masters Theses

In the modern era, maize has become the most successful crop grown in the United States. According to the USDA over 90 million acres of land are planted to corn and 96.2% of the U.S feed grain production is made up of the cereal. Part of the success of maize is due to its floral architecture, and its pollination technique in which the flower opens, exposing stamens containing pollen into the air. A unique organ called the lodicule functions as a release mechanism, forcing the flower to open. Lodicules from grasses and eudicot petals are homologous, yet there ...


Spatial Mapping And Profiling Of Metabolite Distributions During Germination, Adam D. Feenstra, Liza E. Alexander, Zhihong Song, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee Aug 2017

Spatial Mapping And Profiling Of Metabolite Distributions During Germination, Adam D. Feenstra, Liza E. Alexander, Zhihong Song, Andrew R. Korte, Marna D. Yandeau-Nelson, Basil J. Nikolau, Young-Jin Lee

Chemistry Publications

Germination is a highly complex process by which seeds begin to develop and establish themselves as viable organisms. In this paper, we utilize a combination of GC-MS, LC-fluorescence, and mass spectrometry imaging (MSI) approaches to profile and visualize the metabolic distributions of germinating seeds from two different inbreds of maize seeds, B73 and Mo17. GC and LC analyses demonstrate that the two inbreds are highly differentiated in their metabolite profiles throughout the course of germination, especially with regard to amino acids, sugar alcohols, and small organic acids. Crude dissection of the seed followed by GC-MS analysis of polar metabolites also ...


A Comprehensive Analysis Of Alternative Splicing In Paleopolyploid Maize, Wenbin Mei, Sanzhen Liu, James C. Schnable, Cheng-Ting Yeh, Nathan M. Springer, Patrick S. Schnable, William Brad Barbazuk May 2017

A Comprehensive Analysis Of Alternative Splicing In Paleopolyploid Maize, Wenbin Mei, Sanzhen Liu, James C. Schnable, Cheng-Ting Yeh, Nathan M. Springer, Patrick S. Schnable, William Brad Barbazuk

Agronomy & Horticulture -- Faculty Publications

Identifying and characterizing alternative splicing (AS) enables our understanding of the biological role of transcript isoform diversity. This study describes the use of publicly available RNA-Seq data to identify and characterize the global diversity of AS isoforms in maize using the inbred lines B73 and Mo17, and a related species, sorghum. Identification and characterization of AS within maize tissues revealed that genes expressed in seed exhibit the largest differential AS relative to other tissues examined. Additionally, differences in AS between the two genotypes B73 and Mo17 are greatest within genes expressed in seed. We demonstrate that changes in the level ...


Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani Apr 2017

Modeling Gross Primary Production Of Midwest Maize And Soybean Croplands With Satellite And Gridded Weather Data, Gunnar Malek-Madani

Theses and Dissertations in Geography

The gross primary production (GPP) metric is useful in determining trends in the terrestrial carbon cycle. Models that determine GPP utilizing the light use efficiency (LUE) approach in conjunction with biophysical parameters that account for local weather conditions and crop specific factors are beneficial in that they combine the accuracy of the biophysical model with the versatility of the LUE model. One such model developed using in situ data was adapted to operate with remote sensing derived leaf area index (LAI) data and gridded weather datasets. The model, known as the Light Use Efficiency GPP Model (EGM), uses a four ...


An Agrobacterium-Delivered Crispr/Cas9 System For High-Frequency Targeted Mutagenesis In Maize, Si Nian Char, Anjanasree K. Neelakandan, Hartinio Nahampun, Bronwyn Frame, Marcy Main, Martin H. Spalding, Philip W. Becraft, Blake C. Meyers, Virginia Walbot, Kan Wang, Bing Yang Feb 2017

An Agrobacterium-Delivered Crispr/Cas9 System For High-Frequency Targeted Mutagenesis In Maize, Si Nian Char, Anjanasree K. Neelakandan, Hartinio Nahampun, Bronwyn Frame, Marcy Main, Martin H. Spalding, Philip W. Becraft, Blake C. Meyers, Virginia Walbot, Kan Wang, Bing Yang

Genetics, Development and Cell Biology Publications

CRISPR/Cas9 is a powerful genome editing tool in many organisms, including a number of monocots and dicots. Although the design and application of CRISPR/Cas9 is simpler compared to other nuclease-based genome editing tools, optimization requires the consideration of the DNA delivery and tissue regeneration methods for a particular species to achieve accuracy and efficiency. Here, we describe a public sector system, ISU Maize CRISPR, utilizing Agrobacterium-delivered CRISPR/Cas9 for high-frequency targeted mutagenesis in maize. This system consists of an Escherichia coli cloning vector and an Agrobacterium binary vector. It can be used to clone up to four ...


Estimating Yield Gaps At The Cropping System Level, Nicolas Guilpart, Patricio Grassini, Victor O. Sadras, Jagadish Timsina, Kenneth Cassman Jan 2017

Estimating Yield Gaps At The Cropping System Level, Nicolas Guilpart, Patricio Grassini, Victor O. Sadras, Jagadish Timsina, Kenneth Cassman

Agronomy & Horticulture -- Faculty Publications

Yield gap analyses of individual crops have been used to estimate opportunities for increasing crop production at local to global scales, thus providing information crucial to food security. However, increases in crop production can also be achieved by improving cropping system yield through modification of spatial and temporal arrangement of individual crops. In this paper we define the cropping system yield potential as the output from the combination of crops that gives the highest energy yield per unit of land and time, and the cropping system yield gap as the difference between actual energy yield of an existing cropping system ...


Genome-Wide Characterization Of Non-Reference Transposable Element Insertion Polymorphisms Reveals Genetic Diversity In Tropical And Temperate Maize, Xianjun Lai, James C. Schnable, Zhengqiao Liao, Jie Xu, Gengyun Zhang, Chuan Li, Erliang Hu, Tingzhao Rong, Yunbi Xu, Yanli Li Jan 2017

Genome-Wide Characterization Of Non-Reference Transposable Element Insertion Polymorphisms Reveals Genetic Diversity In Tropical And Temperate Maize, Xianjun Lai, James C. Schnable, Zhengqiao Liao, Jie Xu, Gengyun Zhang, Chuan Li, Erliang Hu, Tingzhao Rong, Yunbi Xu, Yanli Li

Agronomy & Horticulture -- Faculty Publications

Background: Maize was originally domesticated in a tropical environment but is now widely cultivated at temperate latitudes. Temperate and tropical maize populations have diverged both genotypically and phenotypically. Tropical maize lines grown in temperate environments usually exhibit delayed flowering, pollination, and seed set, which reduces their grain yield relative to temperate adapted maize lines. One potential mechanism by which temperate maize may have adapted to a new environment is novel transposable element insertions, which can influence gene regulation. Recent advances in sequencing technology have made it possible to study variation in transposon content and insertion location in large sets of ...


Rooting For Food Security In Sub-Saharan Africa, Nicolas Guilpart, Patricio Grassini, Justin Van Wart, Haishun Yang, Martin K. Van Ittersum, Lenny G.J. Van Bussel, Joost Wolf, Lieven Claessens, Johan G.B. Leenaars, Kenneth G. Cassman Jan 2017

Rooting For Food Security In Sub-Saharan Africa, Nicolas Guilpart, Patricio Grassini, Justin Van Wart, Haishun Yang, Martin K. Van Ittersum, Lenny G.J. Van Bussel, Joost Wolf, Lieven Claessens, Johan G.B. Leenaars, Kenneth G. Cassman

Agronomy & Horticulture -- Faculty Publications

There is a persistent narrative about the potential of Sub-Saharan Africa (SSA) to be a ‘grain breadbasket’ because of large gaps between current low yields and yield potential with good management, and vast land resources with adequate rainfall. However, rigorous evaluation of the extent to which soils can support high, stable yields has been limited by lack of data on rootable soil depth of sufficient quality and spatial resolution. Here we use location-specific climate data, a robust spatial upscaling approach, and crop simulation to assess sensitivity of rainfed maize yields to root-zone water holding capacity. We find that SSA could ...


The Role Of Tre6p And Snrk1 In Maize Early Kernel Development And Events Leading To Stress-Induced Kernel Abortion, Samuel W. Bledsoe, Clémence Henry, Cara A. Griffiths, Matthew J. Paul, Regina Feil, John E. Lunn, Mark Stitt, L. Mark Lagrimini Jan 2017

The Role Of Tre6p And Snrk1 In Maize Early Kernel Development And Events Leading To Stress-Induced Kernel Abortion, Samuel W. Bledsoe, Clémence Henry, Cara A. Griffiths, Matthew J. Paul, Regina Feil, John E. Lunn, Mark Stitt, L. Mark Lagrimini

Agronomy & Horticulture -- Faculty Publications

Background: Drought stress during flowering is a major contributor to yield loss in maize. Genetic and biotechnological improvement in yield sustainability requires an understanding of the mechanisms underpinning yield loss. Sucrose starvation has been proposed as the cause for kernel abortion; however, potential targets for genetic improvement have not been identified. Field and greenhouse drought studies with maize are expensive and it can be difficult to reproduce results; therefore, an in vitro kernel culture method is presented as a proxy for drought stress occurring at the time of flowering in maize (3 days after pollination). This method is used to ...


Investigation Of Candidate Loci Associated With Maize Perennialism, Anjun Ma Jan 2017

Investigation Of Candidate Loci Associated With Maize Perennialism, Anjun Ma

Electronic Theses and Dissertations

Developing perennial grain crops is an effective and crucial way to prevent soil erosion caused by conventional agriculture of using annual crops while meeting the increasing need of global food demand. We hypothesized that the regrowth in Zea might be controlled by two dominant complementary genes. F1 hybrids were created by crossing Zea diploperennis Iltis, Doebley & R. Guzman with annual Zea mays L. ssp. mays inbred line B73. A Total of 134 F2 plants derived from nine F1 were planted and phenotyped. A subpopulation of 94 F2 plants were genotyped with Genotype-by- Sequencing (GBS) and called 10,431 SNPs after ...


Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel W. Barker, Ranae Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter J. Thorburn, Sotirios V. Archontoulis Nov 2016

Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel W. Barker, Ranae Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter J. Thorburn, Sotirios V. Archontoulis

Agronomy & Horticulture -- Faculty Publications

Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean (Glycine max L.) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha-1) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) compare ...


Characterization Of Cyp71z18 Indicates A Role In Maize Zealexin Biosynthesis, Hongjie Mao, Jiang Liu, Fei Ren, Reuben J. Peters, Qiang Wang Jan 2016

Characterization Of Cyp71z18 Indicates A Role In Maize Zealexin Biosynthesis, Hongjie Mao, Jiang Liu, Fei Ren, Reuben J. Peters, Qiang Wang

Biochemistry, Biophysics and Molecular Biology Publications

Maize (Zea mays) produces zealexins as phytoalexins, with the inducible production of these antibiotics providing biochemical protection against fungal infection. However, the biosynthesis of these sesquiterpenoids has remained unclear. In particular, it is unclear how the olefinic precursor, (S)-β-macrocarpene produced by the characterized maize sesquiterpene synthases TPS6/11, is further elaborated to form the bioactive zealexins. The first step is likely to be conversion of carbon-15 (C15) from a methyl group to a carboxylic acid by a cytochrome P450 mono-oxygenase (CYP). In this study, CYP71Z18, whose transcription is strongly induced by fungal infection, was found to catalyze oxidation ...


Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez Jan 2016

Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez

Agronomy & Horticulture -- Faculty Publications

It is critical to evaluate conservation practices that protect soil and water resources from climate change in the Midwestern United States, a region that produces one-quarter of the world’s soybeans and one-third of the world’s maize. An over-winter cover crop in a maize–soybean rotation offers multiple potential benefits that can reduce the impacts of higher temperatures and more variable rainfall; some of the anticipated changes for the Midwest. In this experiment we used the Agricultural Production Systems sIMulator (APSIM) to understand how winter rye cover crops impact crop production and environmental outcomes, given future climate change. We ...


Impact Of Derived Global Weather Data On Simulated Crop Yields, Justin Van Wart, Patricio Grassini, Kenneth Cassman Jan 2016

Impact Of Derived Global Weather Data On Simulated Crop Yields, Justin Van Wart, Patricio Grassini, Kenneth Cassman

Agronomy & Horticulture -- Faculty Publications

Crop simulation models can be used to estimate impact of current and future climates on crop yields and food security, but require long-term historical daily weather data to obtain robust simulations. In many regions where crops are grown, daily weather data are not available. Alternatively, gridded weather databases (GWD) with complete terrestrial coverage are available, typically derived from: (i) global circulation computer models; (ii) interpolated weather station data; or (iii) remotely sensed surface data from satellites. The present study’s objective is to evaluate capacity of GWDs to simulate crop yield potential (Yp) or water-limited yield potential (Yw), which can ...


Proteomic Profiling Of Maize Opaque Endosperm Mutants Reveals Selective Accumulation Of Lysine-Enriched Proteins, Kyla J. Morton, Shangang Jia, Chi Zhang, David R. Holding Jan 2016

Proteomic Profiling Of Maize Opaque Endosperm Mutants Reveals Selective Accumulation Of Lysine-Enriched Proteins, Kyla J. Morton, Shangang Jia, Chi Zhang, David R. Holding

Agronomy & Horticulture -- Faculty Publications

Reduced prolamin (zein) accumulation and defective endoplasmic reticulum (ER) body formation occurs in maize opaque endosperm mutants opaque2 (o2), floury2 (fl2), defective endosperm*B30 (DeB30), and Mucronate (Mc), whereas other opaque mutants such as opaque1 (o1) and floury1 (fl1) are normal in these regards. This suggests that other factors contribute to kernel texture. A liquid chromatography approach coupled with tandem mass spectrometry (LC-MS/MS) proteomics was used to compare non-zein proteins of nearly isogenic opaque endosperm mutants. In total, 2762 proteins were identified that were enriched for biological processes such as protein transport and folding, amino acid biosynthesis, and proteolysis ...