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Full-Text Articles in Life Sciences

Potential For Crop Production Increase In Argentina Through Closure Of Existing Yield Gaps, Fernando Aramburu Merlos, Juan Pablo Monzon, Jorge L. Mercau, Miguel Taboada, Fernando H. Andrade, Antonio J. Hall, Esteban Jobbagy, Kenneth Cassman, Patricio Grassini Jan 2015

Potential For Crop Production Increase In Argentina Through Closure Of Existing Yield Gaps, Fernando Aramburu Merlos, Juan Pablo Monzon, Jorge L. Mercau, Miguel Taboada, Fernando H. Andrade, Antonio J. Hall, Esteban Jobbagy, Kenneth Cassman, Patricio Grassini

Department of Agronomy and Horticulture: Faculty Publications

Favorable climate and soils for rainfed crop production, together with a relatively low population density,results in 70–90% of Argentina grain production being exported. No assessment to date has tried to estimate the potential for extra grain production for soybean, wheat and maize, which account for 78%of total harvested area, by yield gap closure on existing cropland area and its impact at a global scale.The objectives of this paper are (i) to estimate how much additional grain could be produced without expanding crop area by closing yield gaps in Argentina, (ii) to investigate how this production and yield gaps varies across …


The Trehalose Pathway In Maize: Conservation And Gene Regulation In Response To The Diurnal Cycle And Extended Darkness, Clémence Henry, Samuel W. Bledsoe, Allison Siekman, Alec Kollman, Brian M. Waters, Regina Feil, Mark Stitt, L. Mark Lagrimini Sep 2014

The Trehalose Pathway In Maize: Conservation And Gene Regulation In Response To The Diurnal Cycle And Extended Darkness, Clémence Henry, Samuel W. Bledsoe, Allison Siekman, Alec Kollman, Brian M. Waters, Regina Feil, Mark Stitt, L. Mark Lagrimini

Department of Agronomy and Horticulture: Faculty Publications

Energy resources in plants are managed in continuously changing environments, such as changes occurring during the day/night cycle. Shading is an environmental disruption that decreases photosynthesis, compromises energy status, and impacts on crop productivity. The trehalose pathway plays a central but not well-defined role in maintaining energy balance. Here, we characterized the maize trehalose pathway genes and deciphered the impacts of the diurnal cycle and disruption of the day/night cycle on trehalose pathway gene expression and sugar metabolism. The maize genome encodes 14 trehalose-6-phosphate synthase (TPS) genes, 11 trehalose-6-phosphate phosphatase (TPP) genes, and one trehalase gene. Transcript abundance of most …


How Do Various Maize Crop Models Vary In Their Responses To Climate Change Factors?, Simon Bassu, Nadine Brisson, Jean-Louis Durand, Kenneth J. Boote, Jon Lizaso, James Jones, Cynthia Rosenzweig, Alex Ruane, Myriam Adam, Christian Baron, Bruno Basso, Christian Biernath, Hendrick Boogaard, Sjaak Conijn, Marc Corbeels, Delphine Deryng, Giacomo De Sanctis, Sebastian Gayler, Patricio Grassini, Jerry Hatfield, Steven Hoek, Cesar Izaurralde, Raymond Jongschaap, Armen Kemanian, Christian Kersebaum, Soo-Hyung Kim, Naresh Kumar, David Makowski, Christoph Muller, Claas Nendel, Eckart Priesack, Maria Virinia Pravia, Federico Sau, Iurii Shcherbak, Fulu Tao, Edmar Teixeira, Dennis Timlin, Katharina Waha Jan 2014

How Do Various Maize Crop Models Vary In Their Responses To Climate Change Factors?, Simon Bassu, Nadine Brisson, Jean-Louis Durand, Kenneth J. Boote, Jon Lizaso, James Jones, Cynthia Rosenzweig, Alex Ruane, Myriam Adam, Christian Baron, Bruno Basso, Christian Biernath, Hendrick Boogaard, Sjaak Conijn, Marc Corbeels, Delphine Deryng, Giacomo De Sanctis, Sebastian Gayler, Patricio Grassini, Jerry Hatfield, Steven Hoek, Cesar Izaurralde, Raymond Jongschaap, Armen Kemanian, Christian Kersebaum, Soo-Hyung Kim, Naresh Kumar, David Makowski, Christoph Muller, Claas Nendel, Eckart Priesack, Maria Virinia Pravia, Federico Sau, Iurii Shcherbak, Fulu Tao, Edmar Teixeira, Dennis Timlin, Katharina Waha

Department of Agronomy and Horticulture: Faculty Publications

Potential consequences of climate change on crop production can be studied using mechanistic crop simulation models. While a broad variety of maize simulation models exist, it is not known whether different models diverge on grain yield responses to changes in climatic factors, or whether they agree in their general trends related to phenology, growth, and yield. With the goal of analyzing the sensitivity of simulated yields to changes in temperature and atmospheric carbon dioxide concentrations [CO2], we present the largest maize crop model intercomparison to date, including 23 different models. These models were evaluated for four locations representing a wide …


Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling Jul 2013

Automated Conserved Non-Coding Sequence (Cns) Discovery Reveals Differences In Gene Content And Promoter Evolution Among Grasses, Gina Marie Turco, James C. Schnable, Brent S. Pedersen, Michael Freeling

Department of Agronomy and Horticulture: Faculty Publications

Conserved non-coding sequences (CNS) are islands of non-coding sequence that, like protein coding exons, show less divergence in sequence between related species than functionless DNA. Several CNSs have been demonstrated experimentally to function as cis-regulatory regions. However, the specific functions of most CNSs remain unknown. Previous searches for CNS in plants have either anchored on exons and only identified nearby sequences or required years of painstaking manual annotation. Here we present an open source tool that can accurately identify CNSs between any two related species with sequenced genomes, including both those immediately adjacent to exons and distal sequences separated by …


Arbuscular Mycorrhizal Fungi Differ In Their Ability To Regulate The Expression Of Phosphate Transporters In Maize (Zea Mays L.), Hui Tian, Rhae A. Drijber, Xiaolin Li, Daniel N. Miller, Brian J. Wienhold Jan 2013

Arbuscular Mycorrhizal Fungi Differ In Their Ability To Regulate The Expression Of Phosphate Transporters In Maize (Zea Mays L.), Hui Tian, Rhae A. Drijber, Xiaolin Li, Daniel N. Miller, Brian J. Wienhold

Department of Agronomy and Horticulture: Faculty Publications

Previous studies have found that some phosphate (Pi) starvation inducible transporter genes are downregulated and arbuscular mycorrhizal (AM) inducible Pi transporter genes are upregulated in maize roots associated with the fungus Glomus intraradices. However, little is known about the functional diversity of different AM fungal species in influencing the expression of Pi transporters in maize roots. Here, we studied the expression of two Pi transporter genes ZEAma:Pht1;3 (Pi starvation inducible) and ZEAma:Pht1;6 (AM inducible) in maize root colonized by different AM fungal inoculants. Non-mycorrhizal maize, maize colonized by Glomus deserticola (CA113), Glomus intraradices (IA506), Glomus mosseae (CA201), Gigaspora gigantea …


Estimating Crop Yield Potential At Regional To National Scales, Justin Van Wart, Kurt Christian Kersebaum, Shaobing Peng, Maribeth Milner, Kenneth Cassman Jan 2013

Estimating Crop Yield Potential At Regional To National Scales, Justin Van Wart, Kurt Christian Kersebaum, Shaobing Peng, Maribeth Milner, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

World population will increase 35% by 2050, which may require doubling crop yields on existing farm land to minimize expansion of agriculture into remaining rainforests, wetlands, and grasslands. Whether this is possible depends on closing the gap between yield potential (Yp, yield without pest, disease, nutrient or water stresses, or Yw under water-limited rainfed conditions) and current average farm yields in both developed and developing countries. Quantifying the yield gap is therefore essential to inform policies and prioritize research to achieve food security without environmental degradation. Previous attempts to estimate Yp and Yw at a global level have been too …


Modulation Of Kernel Storage Proteins In Grain Sorghum (Sorghum Bicolor (L.) Moench), Tejinder Kumar, Ismail M. Dweikat, Shirley Sato, Zhengxiang Ge, Natalya Nersesian, Han Chen, Thomas Elthon, Scott Bean, Brian P. Ioerger, Mike Tilley, Thomas E. Clemente Jan 2012

Modulation Of Kernel Storage Proteins In Grain Sorghum (Sorghum Bicolor (L.) Moench), Tejinder Kumar, Ismail M. Dweikat, Shirley Sato, Zhengxiang Ge, Natalya Nersesian, Han Chen, Thomas Elthon, Scott Bean, Brian P. Ioerger, Mike Tilley, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Sorghum prolamins, termed kafirins, are categorized into subgroups α, β, and γ. The kafirins are co-translationally translocated to the endoplasmic reticulum (ER) where they are assembled into discrete protein bodies that tend to be poorly digestible with low functionality in food and feed applications. As a means to address the issues surrounding functionality and digestibility in sorghum, we employed a biotechnology approach that is designed to alter protein body structure, with the concomitant synthesis of a co-protein in the endosperm fraction of the grain. Wherein perturbation of protein body architecture may provide a route to impact digestibility by reducing disulphide …


High-Yield Irrigated Maize In The Western U.S. Corn Belt: I. On-Farm Yield, Yield Potential, And Impact Of Agronomic Practices, Patricio Grassini, John Thorburn, Charles Burr, Kenneth Cassman Jan 2011

High-Yield Irrigated Maize In The Western U.S. Corn Belt: I. On-Farm Yield, Yield Potential, And Impact Of Agronomic Practices, Patricio Grassini, John Thorburn, Charles Burr, Kenneth Cassman

Department of Agronomy and Horticulture: Faculty Publications

Quantifying the exploitable gap between average farmer yields and yield potential (YP) is essential to prioritize research and formulate policies for food security at national and international levels. While irrigated maize accounts for 58% of total annual maize production in the Western U.S. Corn Belt, current yield gap in these systems has not been quantified. Our objectives were to quantify YP, yield gaps, and the impact of agronomic practices on both parameters in irrigated maize systems of central Nebraska. The analysis was based on a 3-y database with field-specific values for yield, applied irrigation, and N …


High-Yield Irrigated Maize In The Western U.S. Corn Belt: Ii. Irrigation Management And Crop Water Productivity, Patricio Grassini, Haishun Yang, Suat Irmak, John Thorburn, Charles Burr, Kenneth G. Cassman Jan 2011

High-Yield Irrigated Maize In The Western U.S. Corn Belt: Ii. Irrigation Management And Crop Water Productivity, Patricio Grassini, Haishun Yang, Suat Irmak, John Thorburn, Charles Burr, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Appropriate benchmarks for water productivity (WP), defined here as the amount of grain yield produced per unit of water supply, are needed to help identify and diagnose inefficiencies in crop production and water management in irrigated systems. Such analysis is lacking for maize in the Western U.S. Corn Belt where irrigated production represents 58% of total maize output. The objective of this paper was to quantify WP and identify opportunities to increase it in irrigated maize systems of central Nebraska. In the present study, a benchmark for maize WP was (i) developed from relationships between simulated yield and seasonal water …


Inoculation With Arbuscular Mycorrhizal Fungi Or Crop Rotation With Mycorrhizal Plants Improves The Growth Of Maize In Limed Acid Sulfate Soil, Hasao Higo, Katsunori Isobe, Dong-Jin Kang, Kazuhiro Ujie, Rhae A. Drijber, Ryuichi Ishii Jan 2010

Inoculation With Arbuscular Mycorrhizal Fungi Or Crop Rotation With Mycorrhizal Plants Improves The Growth Of Maize In Limed Acid Sulfate Soil, Hasao Higo, Katsunori Isobe, Dong-Jin Kang, Kazuhiro Ujie, Rhae A. Drijber, Ryuichi Ishii

Department of Agronomy and Horticulture: Faculty Publications

Arbuscular mycorrhizal fungi (AMF) improve the uptake of immobile mineral nutrients such as phosphate, thereby improving plant growth. In acid sulfate soil (ASS), AMF spore density is generally low which impacts root colonization and phosphate uptake. Thus, inoculation may help increase AMF colonization of crops grown in ASS. AMF spore density decreases after cultivation of a non-host crop or bare fallow. In addition, preceding crops affect the growth and yield of subsequent crops. The production of AMF inocula requires AMF-compatible plants. The objective of the present study is to elucidate the effect of preceding crops on the persistence of inoculated …


Effects Of Nitrogen Supply On The Root Morphology Of Corn And Velvetleaf, Kimberly D. Bonifas, John L. Lindquist Aug 2009

Effects Of Nitrogen Supply On The Root Morphology Of Corn And Velvetleaf, Kimberly D. Bonifas, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Root morphology will affect interplant competition for soil nutrients. Research was conducted to assess fine root fraction, mean root radius, specific root length, root length density, and nitrogen (N) uptake per unit fine root biomass of corn and velvetleaf over time and in response to nitrogen supply. Pots containing either corn or velvetleaf were embedded in the ground and received one of three N treatments. Plants were destructively sampled on 10 dates during each of two years and root subsamples analyzed using root scanning software. While corn root morphology was more responsive to N supply than velvetleaf, velvetleaf N uptake …


Limits To Maize Productivity In The Western Corn-Belt: A Simulation Analysis For Fully Irrigated And Rainfed Conditions, Patricio Grassini, Haishun Yang, Kenneth G. Cassman Jan 2009

Limits To Maize Productivity In The Western Corn-Belt: A Simulation Analysis For Fully Irrigated And Rainfed Conditions, Patricio Grassini, Haishun Yang, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Unlike the Central and Eastern U.S. Corn-Belt where maize is grown almost entirely under rainfed conditions, maize in the Western Corn-Belt is produced under both irrigated (3.2 million ha) and rainfed (4.1 million ha) conditions. Simulation modeling, regression, and boundary-function analysis were used to assess constraints to maize productivity in the Western Corn-Belt. Aboveground biomass, grain yield, and water balance were simulated for fully irrigated and rainfed crops, using 20-year weather records from 18 locations in combination with actual soil, planting date, plant population, and hybrid-maturity data. Mean values of meteorological variables were estimated for three growth periods (pre- and …


Feasibility Of Site-Specific Management Of Corn Hybrids And Plant Densities In The Great Plains, J.F. Shanahan, Thomas A. Doerge, Jerry J. Johnson, Merle F. Vigil Apr 2004

Feasibility Of Site-Specific Management Of Corn Hybrids And Plant Densities In The Great Plains, J.F. Shanahan, Thomas A. Doerge, Jerry J. Johnson, Merle F. Vigil

Department of Agronomy and Horticulture: Faculty Publications

The goal of this research was to determine the potential for use of site-specific management of corn hybrids and plant densities in dryland landscapes of the Great Plains by determining (1) within-field yield variation, (2) yield response of different hybrids and plant densities to variability, and (3) landscape attributes associated with yield variation. This work was conducted on three adjacent fields in eastern Colorado during the 1997, -98, and -99 seasons. Treatments consisted of a combination of two hybrids (early and late maturity) and four plant densities (24,692, 37,037, 49,382 and 61,727 plants ha-1) seeded in replicated long …