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Genetic Diversity Of Huaya India (Melicoccus Oliviformis Kunth), A Neglected Neotropical Fruit Crop, Mónica I. Jiménez-Rojas, Rubén H. Andueza-Noh, Obed I. Noh-Ake, Daniel Potter, Matilde M. Ortiz-García, Renee S. Arias, Jaime Martínez-Castillo Dec 2021

Genetic Diversity Of Huaya India (Melicoccus Oliviformis Kunth), A Neglected Neotropical Fruit Crop, Mónica I. Jiménez-Rojas, Rubén H. Andueza-Noh, Obed I. Noh-Ake, Daniel Potter, Matilde M. Ortiz-García, Renee S. Arias, Jaime Martínez-Castillo

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Currently, some species of Sapindaceae are important fruit crops worldwide. The Huaya India (Meliccocus oliviformis, Sapindaceae) is a neglected Neotropical fruit tree consumed locally in the Maya Lowlands of Mexico, where it exists in both wild and domesticated forms. Our objective was to evaluate the genetic diversity of the Huaya India in its possible domestication area and thus generate knowledge that serves as the basis for a commercial management. A total of 450 individuals collected from 15 natural vegetation sites and 15 Maya villages, were characterized using nine microsatellite loci and population genetics approaches were applied. STRUCTURE, Neighbor-Joining and PCoA …


A Review Of Transformative Strategies For Climate Mitigation By Grasslands, Nuria Gomez-Casanovas, Elena Blanc-Betes, Caitlin E. Moore, Carl J. Bernacchi, Ilsa Kantola, Evan H. Delucia Dec 2021

A Review Of Transformative Strategies For Climate Mitigation By Grasslands, Nuria Gomez-Casanovas, Elena Blanc-Betes, Caitlin E. Moore, Carl J. Bernacchi, Ilsa Kantola, Evan H. Delucia

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Grasslands can significantly contribute to climate mitigation. However, recent trends indicate that human activities have switched their net cooling effect to a warming effect due to management intensification and land conversion. This indicates an urgent need for strategies directed to mitigate climate warming while enhancing productivity and efficiency in the use of land and natural (nutrients, water) resources. Here, we examine the potential of four innovative strategies to slow climate change including: 1) Adaptive multi-paddock grazing that consists of mimicking how ancestral herds roamed the Earth; 2) Agrivoltaics that consists of simultaneously producing food and energy from solar panels on …


Aspergillus Section Flavi, Need For A Robust Taxonomy, Renee Arias, Valerie A. Orner, Jaime Martinez-Castillo, Victor S. Sobolev Dec 2021

Aspergillus Section Flavi, Need For A Robust Taxonomy, Renee Arias, Valerie A. Orner, Jaime Martinez-Castillo, Victor S. Sobolev

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In a recent letter to the editor, Houbraken et al. (23) provide a series of recommendations to the microbiological community to prevent the taxonomic misidentification of genome-sequenced fungal strains. In the era of genomics and bioinformatics, postulating that 1 nucleotide (nt) within a gene can “correctly” identify a species does not seem plausible. However, the authors of the letter call this the “calmodulin barcode,” meaning nucleotide substitutions within a 506-nt region of the calmodulin gene (1). After the evolutionarily conserved rRNA (18S rRNA, internal transcribed spacer [ITS], 28S rRNA) and RNA polymerase II (2–4) showed no differences between Aspergillus flavus …


Enhanced Drought Resistance Of Vegetation Growth In Cities Due To Urban Heat, Co2 Domes And O3 Troughs, Peng Fu, Leiqiu Hu, Elizabeth A. Ainsworth, Xiaonan Tai, Soe W. Myint, Wenfeng Zhan, Bethany J. Blakely, Carl J. Bernacchi Dec 2021

Enhanced Drought Resistance Of Vegetation Growth In Cities Due To Urban Heat, Co2 Domes And O3 Troughs, Peng Fu, Leiqiu Hu, Elizabeth A. Ainsworth, Xiaonan Tai, Soe W. Myint, Wenfeng Zhan, Bethany J. Blakely, Carl J. Bernacchi

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Sustained increase in atmospheric CO2 is strongly coupled with rising temperature and persistent droughts. While elevated CO2 promotes photosynthesis and growth of vegetation, drier and warmer climate can potentially negate this benefit, complicating the prediction of future terrestrial carbon dynamics. Manipulative studies such as free air CO2 enrichment (FACE) experiments have been useful for studying the joint effect of global change factors on vegetation growth; however, their results do not easily transfer to natural ecosystems partly due to their short-duration nature and limited consideration of climatic gradients and potential confounding factors, such as O3. Urban environments serve as a useful …


Photosynthesis, Yield, Energy Balance, And Water-Use Of Intercropped Maize And Soybean, Elena A. Pelech, Brendan C.S. Alexander, Carl J. Bernacchi Dec 2021

Photosynthesis, Yield, Energy Balance, And Water-Use Of Intercropped Maize And Soybean, Elena A. Pelech, Brendan C.S. Alexander, Carl J. Bernacchi

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

By 2050, the U.S. Corn Belt will likely face a 23% increase in leaf-to-air vapor pressure deficit (VPDL), the driving force of evapotranspiration (ET), which may restrict maize yield improvements for rainfed agroecosystems. Alternative cropping systems, such as maize and legume intercrops, have previously demonstrated yield and resource-use advantages over monocultures. In this study, the residual energy balance approach was used to gain insights into how an additive simultaneous maize and soybean intercrop system regulates ET and water-use efficiency (WUE) compared to standard maize and soybean monoculture systems of the U.S. Corn Belt. Experimental field plots were rain-fed and arranged …


The Genome Of The Stable Fly, Stomoxys Calcitrans, Reveals Potential Mechanisms Underlying Reproduction, Host Interactions, And Novel Targets For Pest Control, Pia U. Olafson, Serap Aksoy, Geoffrey M. Attardo, Greta Buckmeier, Xiaoting Chen, Craig J. Coates, Megan Davis, Justin Dykema, Scott J. Emrich, Markus Friedrich, Christopher J. Holmes, Panagiotis Ioannidis, Evan N. Jansen, Emily C. Jennings, Daniel Lawson, Ellen O. Martinson, Gareth L. Maslen, Richard P. Meisel, Terence D. Murphy, Dana Nayduch, David R. Nelson, Kennan J. Oyen, Tyler J. Raszick, José M.C. Ribeiro, Hugh M. Robertson, Andrew J. Rosendale, Timothy B. Sackton, Perot Saelao, Sonja L. Swiger, Sing Hoi Sze, Aaron M. Tarone, David B. Taylor, Wesley C. Warren, Robert M. Waterhouse, Matthew T. Weirauch, John H. Werren, Richard K. Wilson, Evgeny M. Zdobnov, Joshua B. Benoit Dec 2021

The Genome Of The Stable Fly, Stomoxys Calcitrans, Reveals Potential Mechanisms Underlying Reproduction, Host Interactions, And Novel Targets For Pest Control, Pia U. Olafson, Serap Aksoy, Geoffrey M. Attardo, Greta Buckmeier, Xiaoting Chen, Craig J. Coates, Megan Davis, Justin Dykema, Scott J. Emrich, Markus Friedrich, Christopher J. Holmes, Panagiotis Ioannidis, Evan N. Jansen, Emily C. Jennings, Daniel Lawson, Ellen O. Martinson, Gareth L. Maslen, Richard P. Meisel, Terence D. Murphy, Dana Nayduch, David R. Nelson, Kennan J. Oyen, Tyler J. Raszick, José M.C. Ribeiro, Hugh M. Robertson, Andrew J. Rosendale, Timothy B. Sackton, Perot Saelao, Sonja L. Swiger, Sing Hoi Sze, Aaron M. Tarone, David B. Taylor, Wesley C. Warren, Robert M. Waterhouse, Matthew T. Weirauch, John H. Werren, Richard K. Wilson, Evgeny M. Zdobnov, Joshua B. Benoit

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: The stable fly, Stomoxys calcitrans, is a major blood-feeding pest of livestock that has near worldwide distribution, causing an annual cost of over $2 billion for control and product loss in the USA alone. Control of these flies has been limited to increased sanitary management practices and insecticide application for suppressing larval stages. Few genetic and molecular resources are available to help in developing novel methods for controlling stable flies. Results: This study examines stable fly biology by utilizing a combination of high-quality genome sequencing and RNA-Seq analyses targeting multiple developmental stages and tissues. In conjunction, 1600 genes were …


Publisher Correction: The Genome Of The Stable Fly, Stomoxys Calcitrans, Reveals Potential Mechanisms Underlying Reproduction, Host Interactions, And Novel Targets For Pest Control (Bmc Biology, (2021), 19, 1, (41), 10.1186/S12915-021-00975-9), Pia U. Olafson, Serap Aksoy, Geoffrey M. Attardo, Greta Buckmeier, Xiaoting Chen, Craig J. Coates, Megan Davis, Justin Dykema, Scott J. Emrich, Markus Friedrich, Christopher J. Holmes, Panagiotis Ioannidis, Evan N. Jansen, Emily C. Jennings, Daniel Lawson, Ellen O. Martinson, Gareth L. Maslen, Richard P. Meisel, Terence D. Murphy, Dana Nayduch, David R. Nelson, Kennan J. Oyen, Tyler J. Raszick, José M.C. Ribeiro, Hugh M. Robertson, Andrew J. Rosendale, Timothy B. Sackton, Perot Saelao, Sonja L. Swiger, Sing Hoi Sze, Aaron M. Tarone, David B. Taylor, Wesley C. Warren, Robert M. Waterhouse, Matthew T. Weirauch, John H. Werren, Richard K. Wilson, Evgeny M. Zdobnov, Joshua B. Benoit Dec 2021

Publisher Correction: The Genome Of The Stable Fly, Stomoxys Calcitrans, Reveals Potential Mechanisms Underlying Reproduction, Host Interactions, And Novel Targets For Pest Control (Bmc Biology, (2021), 19, 1, (41), 10.1186/S12915-021-00975-9), Pia U. Olafson, Serap Aksoy, Geoffrey M. Attardo, Greta Buckmeier, Xiaoting Chen, Craig J. Coates, Megan Davis, Justin Dykema, Scott J. Emrich, Markus Friedrich, Christopher J. Holmes, Panagiotis Ioannidis, Evan N. Jansen, Emily C. Jennings, Daniel Lawson, Ellen O. Martinson, Gareth L. Maslen, Richard P. Meisel, Terence D. Murphy, Dana Nayduch, David R. Nelson, Kennan J. Oyen, Tyler J. Raszick, José M.C. Ribeiro, Hugh M. Robertson, Andrew J. Rosendale, Timothy B. Sackton, Perot Saelao, Sonja L. Swiger, Sing Hoi Sze, Aaron M. Tarone, David B. Taylor, Wesley C. Warren, Robert M. Waterhouse, Matthew T. Weirauch, John H. Werren, Richard K. Wilson, Evgeny M. Zdobnov, Joshua B. Benoit

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Following publication of the original article [1], it was reported that the article copyright was incorrect. The correct copyright statement is: © This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply 2021. The original article [1] has been corrected.


Lasting Consequences Of Psyllid (Bactericera Cockerelli L.) Infestation On Tomato Defense, Gene Expression, And Growth, Kyle Harrison, Azucena Mendoza-Herrera, Julien Gad Levy, Cecilia Tamborindeguy Dec 2021

Lasting Consequences Of Psyllid (Bactericera Cockerelli L.) Infestation On Tomato Defense, Gene Expression, And Growth, Kyle Harrison, Azucena Mendoza-Herrera, Julien Gad Levy, Cecilia Tamborindeguy

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: The tomato psyllid, Bactericera cockerelli Šulc (Hemiptera: Triozidae), is a pest of solanaceous crops such as tomato (Solanum lycopersicum L.) in the U.S. and vectors the disease-causing pathogen ‘Candidatus Liberibacter solanacearum’. Currently, the only effective strategies for controlling the diseases associated with this pathogen involve regular pesticide applications to manage psyllid population density. However, such practices are unsustainable and will eventually lead to widespread pesticide resistance in psyllids. Therefore, new control strategies must be developed to increase host-plant resistance to insect vectors. For example, expression of constitutive and inducible plant defenses can be improved through selection. Currently, it is …


Genetic Fingerprinting And Aflatoxin Production Of Aspergillus Section Flavi Associated With Groundnut In Eastern Ethiopia, Abdi Mohammed, Paola C. Faustinelli, Alemayehu Chala, Mashilla Dejene, Chemeda Fininsa, Amare Ayalew, Chris O. Ojiewo, David A. Hoisington, Victor S. Sobolev, Jaime Martínez-Castillo, Renee S. Arias Dec 2021

Genetic Fingerprinting And Aflatoxin Production Of Aspergillus Section Flavi Associated With Groundnut In Eastern Ethiopia, Abdi Mohammed, Paola C. Faustinelli, Alemayehu Chala, Mashilla Dejene, Chemeda Fininsa, Amare Ayalew, Chris O. Ojiewo, David A. Hoisington, Victor S. Sobolev, Jaime Martínez-Castillo, Renee S. Arias

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: Aspergillus species cause aflatoxin contamination in groundnut kernels, being a health threat in agricultural products and leading to commodity rejection by domestic and international markets. Presence of Aspergillus flavus and A. parasiticus colonizing groundnut in eastern Ethiopia, as well as presence of aflatoxins have been reported, though in this region, no genetic studies have been done of these species in relation to their aflatoxin production. Results: In this study, 145 Aspergillus isolates obtained from groundnut kernels in eastern Ethiopia were genetically fingerprinted using 23 Insertion/Deletion (InDel) markers within the aflatoxin-biosynthesis gene cluster (ABC), identifying 133 ABC genotypes. Eighty-four isolates …


Genetic Mapping And Qtl Analysis For Peanut Smut Resistance, Francisco J. De Blas, Cecilia I. Bruno, Renee Arias, Carolina Ballén-Taborda, Eva Mamani, Claudio Oddino, Melina Rosso, Beatriz P. Costero, Marina Bressano, Juan H. Soave, Sara J. Soave, Mario I. Buteler, J. Guillermo Seijo, Alicia Massa Dec 2021

Genetic Mapping And Qtl Analysis For Peanut Smut Resistance, Francisco J. De Blas, Cecilia I. Bruno, Renee Arias, Carolina Ballén-Taborda, Eva Mamani, Claudio Oddino, Melina Rosso, Beatriz P. Costero, Marina Bressano, Juan H. Soave, Sara J. Soave, Mario I. Buteler, J. Guillermo Seijo, Alicia Massa

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: Peanut smut is a disease caused by the fungus Thecaphora frezii Carranza & Lindquist to which most commercial cultivars in South America are highly susceptible. It is responsible for severely decreased yield and no effective chemical treatment is available to date. However, smut resistance has been identified in wild Arachis species and further transferred to peanut elite cultivars. To identify the genome regions conferring smut resistance within a tetraploid genetic background, this study evaluated a RIL population {susceptible Arachis hypogaea subsp. hypogaea (JS17304-7-B) × resistant synthetic amphidiploid (JS1806) [A. correntina (K 11905) × A. cardenasii (KSSc 36015)] × A. …


Soil Hydrologic Grouping Guide Which Soil And Weather Properties Best Estimate Corn Nitrogen Need, Gregory Mac Bean, Curtis J. Ransom, Newell R. Kitchen, Peter C. Scharf, Kristen S. Veum, James J. Camberato, Richard B. Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A.M. Laboski, Emerson D. Nafziger, John E. Sawyer, Robert L. Nielsen Nov 2021

Soil Hydrologic Grouping Guide Which Soil And Weather Properties Best Estimate Corn Nitrogen Need, Gregory Mac Bean, Curtis J. Ransom, Newell R. Kitchen, Peter C. Scharf, Kristen S. Veum, James J. Camberato, Richard B. Ferguson, Fabián G. Fernández, David W. Franzen, Carrie A.M. Laboski, Emerson D. Nafziger, John E. Sawyer, Robert L. Nielsen

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Nitrogen fertilizer recommendations in corn (Zea mays L.) that match the economically optimal nitrogen fertilizer rate (EONR) are imperative for profitability and minimizing environmental degradation. However, the amount of soil N available for the crop depends on soil and weather factors, making it difficult to know the EONR from year-to-year and from field-to-field. Our objective was to explore, within the framework of hydrologic soil groups and drainage classifications (HGDC), which site-specific soil and weather properties best estimated corn N needs (i.e., EONR) for two application timings (at-planting and side-dress). Included in this investigation was a validation step using an independent …


Land Management Effects On Wet Aggregate Stability And Carbon Content, Maysoon M. Mikha, Virginia L. Jin, Jane M.F. Johnson, R Michael Lehman, Douglas L. Karlen, Jalal D. Jabro Aug 2021

Land Management Effects On Wet Aggregate Stability And Carbon Content, Maysoon M. Mikha, Virginia L. Jin, Jane M.F. Johnson, R Michael Lehman, Douglas L. Karlen, Jalal D. Jabro

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Land management affects soil structure and many other soil properties and processes. Our objectives were to evaluate soil organic C (SOC), aggregate size distribution, aggregate-associated C, and soil structure as affected by long-term land management and slope. A chronosequence of 38 on-farm sites with low to high (5–18%) slopes was selected to evaluate 5–40 yr of management. The sites were classified as business as usual (BAU) cropland (BAU-Crop), BAU pasture (BAU-Past), newly established conservation reserve program (CRP) areas (CRP-New), and established CRP (CRP-Old). Soil samples were collected from the 0-to-5- and 5-to-15-cm depth increments and processed for soil property measurements …


Effects Of The Functional Gpc-­B1 Allele On Soft Durum Wheat Grain, Milling, Flour, Dough, And Breadmaking Quality, Alecia M. Kiszonas, Maria Itria Ibba, Jeffrey D. Boehm Jr, Craig F. Morris Aug 2021

Effects Of The Functional Gpc-­B1 Allele On Soft Durum Wheat Grain, Milling, Flour, Dough, And Breadmaking Quality, Alecia M. Kiszonas, Maria Itria Ibba, Jeffrey D. Boehm Jr, Craig F. Morris

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background and objectives: Utilization of durum wheat (Triticum turgidum subsp. durum) can be enhanced by increasing grain and flour protein content. One strategy to increase protein content is by introducing the functional Gpc-B1 allele from wild emmer (Triticum turgidum subsp. dicoccoides). Findings: Introduction of the functional Gpc-B1 allele into soft kernel durum increased grain and flour protein by 17 g/kg, increased dough strength as evidenced by SDS sedimentation volume and Mixograph dough mixing parameters, and increased straight-dough pan bread volume. When grown under arid conditions, high protein (151 g/kg) samples had decreased loaf volumes indicative of inelastic doughs. The functional …


Soil Greenhouse Gas Responses To Biomass Removal In The Annual And Perennial Cropping Phases Of An Integrated Crop Livestock System, Elizabeth Christenson, Virginia L. Jin, Marty R. Schmer, Robert B. Mitchell, Daren D. Redfearn Jul 2021

Soil Greenhouse Gas Responses To Biomass Removal In The Annual And Perennial Cropping Phases Of An Integrated Crop Livestock System, Elizabeth Christenson, Virginia L. Jin, Marty R. Schmer, Robert B. Mitchell, Daren D. Redfearn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Diversifying agronomic production systems by combining crops and livestock (i.e., Integrated Crop Livestock systems; ICL) may help mitigate the environmental impacts of intensive single-commodity production. In addition, harvesting row-crop residues and/or perennial biomass could increase the multi-functionality of ICL systems as a potential source for second-generation bioenergy feedstock. Here, we evaluated non-CO2 soil greenhouse gas (GHG) emissions from both row-crop and perennial grass phases of a field-scale model ICL system established on marginally productive, poorly drained cropland in the western US Corn Belt. Soil emissions of nitrous oxide (N2O) and methane (CH4 ) were measured during the 2017–2019 growing seasons …


Nitrogen Fertilization And Native C4 Grass Species Alter Abundance, Activity, And Diversity Of Soil Diazotrophic Communities, Jialin Hu, Jonathan D. Richwine, Patrick D. Keyser, Lidong Li, Fei Yao, Sindhu Jagadamma, Jennifer M. Debruyn Jul 2021

Nitrogen Fertilization And Native C4 Grass Species Alter Abundance, Activity, And Diversity Of Soil Diazotrophic Communities, Jialin Hu, Jonathan D. Richwine, Patrick D. Keyser, Lidong Li, Fei Yao, Sindhu Jagadamma, Jennifer M. Debruyn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Native C4 grasses have become the preferred species for native perennial pastures and bioenergy production due to their high productivity under low soil nitrogen (N) status. One reason for their low N requirement is that C4 grasses may benefit from soil diazotrophs and promote biological N fixation. Our objective was to evaluate the impact of N fertilization rates (0, 67, and 202 kg N ha−1 ) and grass species (switchgrass [Panicum virgatum] and big bluestem [Andropogon gerardii]) on the abundance, activity, diversity, and community composition of soil diazotrophs over three agricultural seasons (grass green-up, initial harvest, and second …


Early Corn Stand Count Of Different Cropping Systems Using Uav-Imagery And Deep Learning, Chin Nee Vong, Lance S. Conway, Jianfeng Zhou, Newell R. Kitchen, Kenneth A. Sudduth Jul 2021

Early Corn Stand Count Of Different Cropping Systems Using Uav-Imagery And Deep Learning, Chin Nee Vong, Lance S. Conway, Jianfeng Zhou, Newell R. Kitchen, Kenneth A. Sudduth

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Optimum plant stand density and uniformity is vital in order to maximize corn (Zea mays L.) yield potential. Assessment of stand density can occur shortly after seedlings begin to emerge, allowing for timely replant decisions. The conventional methods for evaluating an early plant stand rely on manual measurement and visual observation, which are time consuming, subjective because of the small sampling areas used, and unable to capture field-scale spatial variability. This study aimed to evaluate the feasibility of an unmanned aerial vehicle (UAV)-based imaging system for estimating early corn stand count in three cropping systems (CS) with different tillage and …


Can Improved Canopy Light Transmission Ameliorate Loss Of Photosynthetic Efficiency In The Shade An Investigation Of Natural Variation In Sorghum Bicolor, Nikhil S. Jaikumar, Samantha S. Stutz, Samuel B. Fernandes, Andrew D.B. Leakey, Carl J. Bernacchi, Patrick J. Brown, Stephen P. Long Jun 2021

Can Improved Canopy Light Transmission Ameliorate Loss Of Photosynthetic Efficiency In The Shade An Investigation Of Natural Variation In Sorghum Bicolor, Nikhil S. Jaikumar, Samantha S. Stutz, Samuel B. Fernandes, Andrew D.B. Leakey, Carl J. Bernacchi, Patrick J. Brown, Stephen P. Long

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Previous studies have found that maximum quantum yield of CO2 assimilation (φCO2,max,app) declines in lower canopies of maize and miscanthus, a maladaptive response to self-shading. These observations were limited to single genotypes, leaving it unclear whether the maladaptive shade response is a general property of this C4 grass tribe, the Andropogoneae. We explored the generality of this maladaptation by testing the hypothesis that erect leaf forms (erectophiles), which allow more light into the lower canopy, suffer less of a decline in photosynthetic efficiency than drooping leaf (planophile) forms. On average, φCO2,max,app declined 27% in lower canopy leaves across 35 accessions, …


Soil Quality Assessment Of An Agroforestry System Following Long-Term Management In The Ozark Highlands, Shane Ylagan, Helen C.S. Amorim, Amanda J. Ashworth, Tom Sauer, Brian J. Wienhold, Phillip R. Owens, Yuri L. Zinn, Kristofor R. Brye Jun 2021

Soil Quality Assessment Of An Agroforestry System Following Long-Term Management In The Ozark Highlands, Shane Ylagan, Helen C.S. Amorim, Amanda J. Ashworth, Tom Sauer, Brian J. Wienhold, Phillip R. Owens, Yuri L. Zinn, Kristofor R. Brye

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The Soil Management Assessment Framework (SMAF) is a quantitative soil quality (SQ) evaluation tool that is widely applied to assess soil response to specific agricultural management practices over time. Considering the reported SQ benefits of agroforestry (AF) systems and the potential usefulness of SMAF, the objective of this study was to evaluate the effects of tree species (pecan [Carya illinoinensis (Wangenh.) K. Koch] and northern red oak [Quercus rubra L.]), soil fertility source (poultry litter [PL] and inorganic N fertilizer [control]), and soil depth (0–15 and 15–30 cm) on SMAF-derived SQ indices after 17 yr of management at an AF …


Quantifying High-Temperature Stress On Soybean Canopy Photosynthesis: The Unique Role Of Sun-Induced Chlorophyll Fluorescence, Hyungsuk Kimm, Kaiyu Guan, Charles H. Burroughs, Bin Peng, Elizabeth A. Ainsworth, Carl J. Bernacchi, Caitlin E. Moore, Etsushi Kumagai, Xi Yang, Joseph A. Berry, Genghong Wu Jun 2021

Quantifying High-Temperature Stress On Soybean Canopy Photosynthesis: The Unique Role Of Sun-Induced Chlorophyll Fluorescence, Hyungsuk Kimm, Kaiyu Guan, Charles H. Burroughs, Bin Peng, Elizabeth A. Ainsworth, Carl J. Bernacchi, Caitlin E. Moore, Etsushi Kumagai, Xi Yang, Joseph A. Berry, Genghong Wu

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

High temperature and accompanying high vapor pressure deficit often stress plants without causing distinctive changes in plant canopy structure and consequential spectral signatures. Sun-induced chlorophyll fluorescence (SIF), because of its mechanistic link with photosynthesis, may better detect such stress than remote sensing techniques relying on spectral reflectance signatures of canopy structural changes. However, our understanding about physiological mechanisms of SIF and its unique potential for physiological stress detection remains less clear. In this study, we measured SIF at a high-temperature experiment, Temperature Free-Air Controlled Enhancement, to explore the potential of SIF for physiological investigations. The experiment provided a gradient of …


Representativeness Of Eddy-Covariance Flux Footprints For Areas Surrounding Ameriflux Sites, Housen Chu, Xiangzhong Luo, Zutao Ouyang, W. Stephen Chan, Sigrid Dengel, Sébastien C. Biraud, Margaret S. Torn, Stefan Metzger, Jitendra Kumar, M. Altaf Arain, Tim J. Arkebauer, Dennis Baldocchi, Carl Bernacchi, Dave Billesbach, T. Andrew Black, Peter D. Blanken, Gil Bohrer, Rosvel Bracho, Shannon Brown, Nathaniel A. Brunsell, Jiquan Chen, Xingyuan Chen, Kenneth Clark, Ankur R. Desai, Tomer Duman, David Durden, Silvano Fares, Inke Forbrich, John A. Gamon, Christopher M. Gough, Timothy Griffis, Manuel Helbig, David Hollinger, Elyn Humphreys, Hiroki Ikawa, Hiroki Iwata, Yang Ju, John F. Knowles, Sara H. Knox, Hideki Kobayashi May 2021

Representativeness Of Eddy-Covariance Flux Footprints For Areas Surrounding Ameriflux Sites, Housen Chu, Xiangzhong Luo, Zutao Ouyang, W. Stephen Chan, Sigrid Dengel, Sébastien C. Biraud, Margaret S. Torn, Stefan Metzger, Jitendra Kumar, M. Altaf Arain, Tim J. Arkebauer, Dennis Baldocchi, Carl Bernacchi, Dave Billesbach, T. Andrew Black, Peter D. Blanken, Gil Bohrer, Rosvel Bracho, Shannon Brown, Nathaniel A. Brunsell, Jiquan Chen, Xingyuan Chen, Kenneth Clark, Ankur R. Desai, Tomer Duman, David Durden, Silvano Fares, Inke Forbrich, John A. Gamon, Christopher M. Gough, Timothy Griffis, Manuel Helbig, David Hollinger, Elyn Humphreys, Hiroki Ikawa, Hiroki Iwata, Yang Ju, John F. Knowles, Sara H. Knox, Hideki Kobayashi

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Large datasets of greenhouse gas and energy surface-atmosphere fluxes measured with the eddy-covariance technique (e.g., FLUXNET2015, AmeriFlux BASE) are widely used to benchmark models and remote-sensing products. This study addresses one of the major challenges facing model-data integration: To what spatial extent do flux measurements taken at individual eddy-covariance sites reflect model- or satellite-based grid cells? We evaluate flux footprints—the temporally dynamic source areas that contribute to measured fluxes—and the representativeness of these footprints for target areas (e.g., within 250–3000 m radii around flux towers) that are often used in flux-data synthesis and modeling studies. We examine the land-cover composition …


Phenological Corrections To A Field-Scale, Et-Based Crop Stress Indicator: An Application To Yield Forecasting Across The U.S. Corn Belt, Yang Yang, Martha C. Anderson, Feng Gao, David M. Johnson, Yun Yang, Liang Sun, Wayne Dulaney, Christopher R. Hain, Jason A. Otkin, John Prueger, Tilden P. Meyers, Carl J. Bernacchi, Caitlin E. Moore May 2021

Phenological Corrections To A Field-Scale, Et-Based Crop Stress Indicator: An Application To Yield Forecasting Across The U.S. Corn Belt, Yang Yang, Martha C. Anderson, Feng Gao, David M. Johnson, Yun Yang, Liang Sun, Wayne Dulaney, Christopher R. Hain, Jason A. Otkin, John Prueger, Tilden P. Meyers, Carl J. Bernacchi, Caitlin E. Moore

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Soil moisture deficiency is a major factor in determining crop yields in water-limited agricultural production regions. Evapotranspiration (ET), which consists of crop water use through transpiration and water loss through direct soil evaporation, is a good indicator of soil moisture availability and vegetation health. ET therefore has been an integral part of many yield estimation efforts. The Evaporative Stress Index (ESI) is an ET-based crop stress indicator that describes temporal anomalies in a normalized evapotranspiration metric as derived from satellite remote sensing. ESI has demonstrated the capacity to explain regional yield variability in water-limited regions. However, its performance in some …


Effects Of Residue Removal And Tillage On Greenhouse Gas Emissions In Continuous Corn Systems As Simulated With Rzwqm2, Haomiao Cheng, Kexin Shu, Zhiming Qi, Liwang Ma, Virginia L. Jin, Youjia Li, Marty R. Schmer, Brian J. Wienhold, Shaoyuan Feng May 2021

Effects Of Residue Removal And Tillage On Greenhouse Gas Emissions In Continuous Corn Systems As Simulated With Rzwqm2, Haomiao Cheng, Kexin Shu, Zhiming Qi, Liwang Ma, Virginia L. Jin, Youjia Li, Marty R. Schmer, Brian J. Wienhold, Shaoyuan Feng

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Agricultural production is a major source of carbon dioxide (CO2) and nitrous oxide (N2O) globally. The effects of conservation practices on soil CO2 and N2O emissions remain a high degree of uncertainty. In this study, soil CO2 and N2O emissions under different residue and tillage practices in an irrigated, continuous corn system, were investigated using the Root Zone Water Quality Model (RZWQM2). Combinations of no/high stover removal (NR and HR, respectively) and no-till/conventional tillage (NT and CT, respectively) field experiments were tested over the four crop-years (Apr. 2011–Apr. 2015). The model was calibrated using the NRCT, and validated with other …


Emerging Approaches To Measure Photosynthesis From The Leaf To The Ecosystem, Matthew H. Siebers, Nuria Gomez-Casanovas, Peng Fu, Katherine Meacham-Hensold, Caitlin E. Moore, Carl J. Bernacchi May 2021

Emerging Approaches To Measure Photosynthesis From The Leaf To The Ecosystem, Matthew H. Siebers, Nuria Gomez-Casanovas, Peng Fu, Katherine Meacham-Hensold, Caitlin E. Moore, Carl J. Bernacchi

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Measuring photosynthesis is critical for quantifying and modeling leaf to regional scale productivity of managed and natural ecosystems. This review explores existing and novel advances in photosynthesis measurements that are certain to provide innovative directions in plant science research. First, we address gas exchange approaches from leaf to ecosystem scales. Leaf level gas exchange is a mature method but recent improvements to the user interface and environmental controls of commercial systems have resulted in faster and higher quality data collection. Canopy chamber and micrometeorological methods have also become more standardized tools and have an advanced understanding of ecosystem functioning under …


Sorghum Brown Midrib19 (Bmr19) Gene Links Lignin Biosynthesis To Folate Metabolism, Adedayo O. Adeyanju, Scott E. Sattler, Patrick J. Rich, Luis A. Rivera-Burgos, Xiaochen Xu, Gebisa Ejeta Apr 2021

Sorghum Brown Midrib19 (Bmr19) Gene Links Lignin Biosynthesis To Folate Metabolism, Adedayo O. Adeyanju, Scott E. Sattler, Patrick J. Rich, Luis A. Rivera-Burgos, Xiaochen Xu, Gebisa Ejeta

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Genetic analysis of brown midrib sorghum (Sorghum bicolor) mutant lines assembled in our program has previously shown that the mutations fall into four allelic groups, bmr2, bmr6, bmr12 or bmr19. Causal genes for allelic groups bmr2, bmr6 and bmr12, have since been identified. In this report, we provide evidence for the nature of the bmr19 mutation. This was accomplished by introgressing each of the four bmr alleles into nine different genetic backgrounds. Polymorphisms from four resequenced bulks of sorghum introgression lines containing either mutation, relative to those of a resequenced bulk of the nine normal midrib recurrent parent lines, were …


Late-Seeded Cover Crops In A Semiarid Environment: Overyielding, Dominance And Subsequent Crop Yield, John R. Hendrickson, Mark A. Liebig, David W. Archer, Marty Schmer, Kristine A. Nichols, Donald L. Tanaka Apr 2021

Late-Seeded Cover Crops In A Semiarid Environment: Overyielding, Dominance And Subsequent Crop Yield, John R. Hendrickson, Mark A. Liebig, David W. Archer, Marty Schmer, Kristine A. Nichols, Donald L. Tanaka

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Interest in cover crops is increasing but information is limited on integrating them into crop rotations especially in the relatively short growing season on the northern Great Plains. A 3-yr research project, initiated in 2009 near Mandan, North Dakota, USA, evaluated (1) what impact cover crops may have on subsequent cash crops yields and (2) whether cover crop mixtures are more productive and provide additional benefits compared to cover crop monocultures. The study evaluated 18 different cover crop monocultures and mixtures that were seeded in August following dry pea (Pisum sativum L.). The following year, spring wheat (Triticum aestivum L.), …


Do Long-Term Conservation Pasture Management Practices Influence Microbial Diversity And Antimicrobial Resistant Genes In Runoff?, Yichao Yang, Amanda J. Ashworth, Lisa M. Durso, Mary Savin, Jennifer M. Debruyn, Kimberly Cook, Philip A. Moore Jr, Philip R. Owens Apr 2021

Do Long-Term Conservation Pasture Management Practices Influence Microbial Diversity And Antimicrobial Resistant Genes In Runoff?, Yichao Yang, Amanda J. Ashworth, Lisa M. Durso, Mary Savin, Jennifer M. Debruyn, Kimberly Cook, Philip A. Moore Jr, Philip R. Owens

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Runoff from land-applied manure and poultry litter is one mechanism by which manure-borne bacteria are transported over large distances in the environment. There is a global concern that antimicrobial resistant (AMR) genes may be transmitted through the food chain from animal manures to soil to surface water. However, details are lacking on the ecology of AMR genes in water runoff as well as how conservation management practices may affect the runoff microbiome or minimize the movement of AMR genes. The aim of this study was to identify microbial community structure and diversity in water runoff following 14-years of poultry litter …


The Effect Of Increasing Temperature On Crop Photosynthesis: From Enzymes To Ecosystems, Caitlin E. Moore, Katherine Meacham-Hensold, Pauline Lemonnier, Rebecca A. Slattery, Claire Benjamin, Carl J. Bernacchi, Tracy Lawson, Amanda P. Cavanagh Apr 2021

The Effect Of Increasing Temperature On Crop Photosynthesis: From Enzymes To Ecosystems, Caitlin E. Moore, Katherine Meacham-Hensold, Pauline Lemonnier, Rebecca A. Slattery, Claire Benjamin, Carl J. Bernacchi, Tracy Lawson, Amanda P. Cavanagh

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

As global land surface temperature continues to rise and heatwave events increase in frequency, duration, and/or intensity, our key food and fuel cropping systems will likely face increased heat-related stress. A large volume of literature exists on exploring measured and modelled impacts of rising temperature on crop photosynthesis, from enzymatic responses within the leaf up to larger ecosystem-scale responses that reflect seasonal and interannual crop responses to heat. This review discusses (i) how crop photosynthesis changes with temperature at the enzymatic scale within the leaf; (ii) how stomata and plant transport systems are affected by temperature; (iii) what features make …


Seasonal Variation In The Effects Of Urban Environmental Factors On Land Surface Temperature In A Winter City, Wen Wu, Lidong Li, Chunlin Li Mar 2021

Seasonal Variation In The Effects Of Urban Environmental Factors On Land Surface Temperature In A Winter City, Wen Wu, Lidong Li, Chunlin Li

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Environmental factors such as urban landscape patterns, local climate, topography, and socioeconomic conditions have significant impacts on land surface temperature (LST), especially through the urban heat island effect. At present, in-depth studies on the mechanisms determining LST in different seasons in winter cities are lacking. In this study, we used structural equation modeling for 12 environmental factors to characterize how these factors affect the temporal and spatial heterogeneity of the LST in the winter city of Shenyang, China. We found that the most critical factors affecting LST varied with season. Specifically, the distances from the nearest water body and nearest …


Conservation Management Improves Agroecosystem Function And Resilience Of Soil Nitrogen Cycling In Response To Seasonal Changes In Climate, Lidong Li, Julie Konkel, Virginia L. Jin, Sean M. Schaeffer Mar 2021

Conservation Management Improves Agroecosystem Function And Resilience Of Soil Nitrogen Cycling In Response To Seasonal Changes In Climate, Lidong Li, Julie Konkel, Virginia L. Jin, Sean M. Schaeffer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Understanding how conservation agricultural management improves soil nitrogen (N) stability in the face of climate change can help increase agroecosystem productivity and mitigate runoff, leaching and downstream water quality issues. We conducted a 2-year field study in a 36-year-old rain-fed cotton production system to evaluate the impacts of changing climatic factors (temperature and precipitation) on soil N under conservation management, including moderate inorganic N fertilizer application (0 and 67 kg N ha−1 ), winter cover crops (fallow; winter wheat, Triticum aestivum L.; hairy vetch, Vicia villosa Roth), and reduced tillage (no-till; disk tillage). Structural equation modeling (SEM) was used …


Variations In Bacterial Community Structure And Antimicrobial Resistance Gene Abundance In Cattle Manure And Poultry Litter, Biyensa Gurmessa, Amanda J. Ashworth, Yichao Yang, Mary Savin, Philip A. Moore Jr, Steven C. Ricke, Giuseppe Corti, Ester Foppa Pedretti, Stefania Cocco Mar 2021

Variations In Bacterial Community Structure And Antimicrobial Resistance Gene Abundance In Cattle Manure And Poultry Litter, Biyensa Gurmessa, Amanda J. Ashworth, Yichao Yang, Mary Savin, Philip A. Moore Jr, Steven C. Ricke, Giuseppe Corti, Ester Foppa Pedretti, Stefania Cocco

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Cattle manure and poultry litter are widely used as fertilizers as they are excellent sources of nutrients; however, potential adverse environmental effects exist during land applications, due to the release of zoonotic bacteria and antimicrobial resistance (AMR) genes. This study was conducted to understand linkages between physiochemical composition, bacterial diversity, and AMR gene presence of cattle manure and poultry litter using quantitative polymerase chain reaction to enumerate four AMR genes (ermB, sulI, intlI, and blactx-m-32), Illumina sequencing of the 16 S region, and analysis of physical and chemical properties. Principal coordinate analysis of Bray–Curtis distance revealed distinct bacterial community structures …