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Agronomy and Crop Sciences

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Articles 1 - 30 of 10351

Full-Text Articles in Life Sciences

Stability Analysis Of Kernel Quality Traits In Exotic-Derived Doubled Haploid Maize Lines, Adam Vanous, Candice Gardner, Michael Blanco, Adam Martin-Schwarze, Jinyu Wang, Xianran Li, Alexander E. Lipka, Sherry Flint-Garcia, Martin Bohn, Jode Edwards, Thomas Lubberstedt Mar 2019

Stability Analysis Of Kernel Quality Traits In Exotic-Derived Doubled Haploid Maize Lines, Adam Vanous, Candice Gardner, Michael Blanco, Adam Martin-Schwarze, Jinyu Wang, Xianran Li, Alexander E. Lipka, Sherry Flint-Garcia, Martin Bohn, Jode Edwards, Thomas Lubberstedt

Agronomy Publications

Variation in kernel composition across maize (Zea mays L.) germplasm is affected by a combination of the plant’s genotype, the environment in which it is grown, and the interaction between these two elements. Adapting exotic germplasm to the US Corn Belt is highly dependent on the plant’s genotype, the environment where it is grown, and the interaction between these components. Phenotypic plasticity is ill-defined when specific exotic germplasm is moved over large latitudinal distances and for the adapted variants being created. Reduced plasticity (or stability) is desired for the adapted variants, as it allows for a more rapid ...


Planting Date, Hybrid Maturity, And Weather Effects On Maize Yield And Crop Stage, M. E. Baum, S. V. Archontoulis, M. A. Licht Jan 2019

Planting Date, Hybrid Maturity, And Weather Effects On Maize Yield And Crop Stage, M. E. Baum, S. V. Archontoulis, M. A. Licht

Agronomy Publications

Unfavorable weather conditions frequently cause farmers to plant maize (Zea mays L.) outside the optimum planting timeframe. We analyzed maize yield and phenology from a multilocation, year, hybrid relative maturity, and planting date experiment performed in Iowa, USA. Our objectives were to determine the optimum combination of planting date and relative maturity to maximize maize grain yield per environment and to elucidate the risk associated with the use of “full-season hybrids” when planting occurs beyond the optimum planting date. Analysis of variance (ANOVA) attributed 70% of the variability in grain yield to planting date and only 10% to relative maturity ...


Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza Dec 2018

Risks And Opportunities Of Gm Crops: Bt Maize Example, Andrea K. Carzoli, Siddique I. Aboobucker, Leah L. Sandall, Thomas T. Lubberstedt, Walter P. Suza

Agronomy Publications

The anticipated world population growth emphasizes a need to produce more food on less land. Cutting-edge technologies, including genetic engineering, can help to develop improved crop varieties and protect natural resources. In spite of the potential for genetically-modified (GM) crops to make crop production more efficient, they remain a polarizing issue due to safety concerns. This paper provides an overview of the risk assessment process. The safety of Bacillus thuringiensis (Bt) proteins is used as an example for how risk assessment is applied to GM crops. Risks associated with GM crops have proven to be low to non-existent. Developing countries ...


Understanding Spatial Dynamics Of Tallgrass Prairie Dominated By Tall Fescue, Callie Griffith Dec 2018

Understanding Spatial Dynamics Of Tallgrass Prairie Dominated By Tall Fescue, Callie Griffith

Theses, Dissertations, and Student Research in Agronomy and Horticulture

This study was conducted on restored tallgrass prairie and invaded tallgrass prairie located in the Grand River Grasslands of southern Iowa to determine differences in heterogeneity of plant structure and functional group composition at different scales. Restored tallgrass prairies were seeded with a species-rich seeding mixture and managed by burning the entire prairie, every three years. Data were collected in August 2014 and 2015 to compare heterogeneity of restoration of native plant structure and functional group composition to the heterogeneity of invaded tallgrass prairies that were managed with patch burning and conventionally grazed. Invaded tallgrass prairies were managed with patch-burning ...


Systems To Attract And Feed Pollinators In Warm-Season Lawns, Michelle Wisdom Dec 2018

Systems To Attract And Feed Pollinators In Warm-Season Lawns, Michelle Wisdom

Theses and Dissertations

Pollinating insects are responsible for the production of many agricultural crops and they require floral resources to fulfill their life-cycle. Ideally, pollinating insects will encounter a diversity of floral resources across their entire season of activity, and those floral resources can include both herbaceous and woody plant species. Managed turfgrass areas have been identified as potential locations for creating pollinator-friendly habitats. In the transition zone, where both warm- and cool-season turfgrass species are present, the persistence of herbaceous plants in warm-season turfgrasses such as bermudagrass (Cynodon spp.) and buffalograss (Buchloe dactyloides), may be affected not only by the competitive nature ...


Generation And Evaluation Of Modified Opaque-2 (O2) Popcorn Suggests A Route To Quality Protein Popcorn (Qpp), Ying Ren Dec 2018

Generation And Evaluation Of Modified Opaque-2 (O2) Popcorn Suggests A Route To Quality Protein Popcorn (Qpp), Ying Ren

Theses, Dissertations, and Student Research in Agronomy and Horticulture

I have been working on a Quality Protein Popcorn breeding project where QPM conversion is carried out simultaneously for several elite popcorn germplasms. During my study in the graduate program, I led the following aspects of the Quality Protein Popcorn Breeding Project:

1. Identified suitable QPMs as opaque-2 allele donors.

2.Examined the feasibility of quick introgression of the opaque-2 allele into popcorn lines via marker-assisted selection.

3. Monitored modification by SDS-PAGE zein profiling and light box phenotypic selection to make sure multiple modifier loci for opaque-2 were incorporated each time generation advancement was carried out.

4. Carried out high ...


Genotypic Variation In Anthocyanins, Phenolic Compounds, And Antioxidant Activity In Cob And Husk Of Purple Field Corn, Ponsawan Khamphasan, Khomsorn Lomthaisong, Bhornchai Harakotr, Danupol Ketthaisong, Marvin Paul Scott, Kamol Lertrat, Bhalang Suriharn Nov 2018

Genotypic Variation In Anthocyanins, Phenolic Compounds, And Antioxidant Activity In Cob And Husk Of Purple Field Corn, Ponsawan Khamphasan, Khomsorn Lomthaisong, Bhornchai Harakotr, Danupol Ketthaisong, Marvin Paul Scott, Kamol Lertrat, Bhalang Suriharn

Agronomy Publications

Information on phytochemicals in the cob and husk of field corn is important for the use of corn waste in the production of value-added corn products. The objectives of this study were to evaluate the variation in monomeric anthocyanin content (MAC), total phenolic content (TPC), and antioxidant activity, as determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and Trolox equivalent antioxidant capacity (TEAC) in 53 purple field corn genotypes, and to study the correlations of these traits with color parameters. Fifty-three corn genotypes were planted in a randomized complete block design with three replications in two locations in the ...


Haplotype Loci Under Selection In Canadian Durum Wheat Germplasm Over 60 Years Of Breeding: Association With Grain Yield, Quality Traits, Protein Loss, And Plant Height, Amidou N'Diaye, Jemanesh K. Haile, Kirby T. Nilsen, Sean Walkowiak, Yuefeng Ruan, Asheesh K. Singh, Fran R. Clarke, John M. Clarke, Curtis J. Pozniak Nov 2018

Haplotype Loci Under Selection In Canadian Durum Wheat Germplasm Over 60 Years Of Breeding: Association With Grain Yield, Quality Traits, Protein Loss, And Plant Height, Amidou N'Diaye, Jemanesh K. Haile, Kirby T. Nilsen, Sean Walkowiak, Yuefeng Ruan, Asheesh K. Singh, Fran R. Clarke, John M. Clarke, Curtis J. Pozniak

Agronomy Publications

Durum wheat was introduced in the southern prairies of western Canada in the late nineteenth century. Breeding efforts have mainly focused on improving quality traits to meet the pasta industry demands. For this study, 192 durum wheat lines were genotyped using the Illumina 90K Infinium iSelect assay, and resulted in a total of 14,324 polymorphic SNPs. Genetic diversity changed over time, declining during the first 20 years of breeding in Canada, then increased in the late 1980s and early 1990s. We scanned the genome for signatures of selection, using the total variance Fst-based outlier detection method (Lositan), the hierarchical ...


Investigation Of Alternative Hosts And Agronomic Factors Affecting Xanthomonas Vasicola Pv. Vasculorum, Causal Agent Of Bacterial Leaf Streak Of Corn, Terra Marie Hartman Nov 2018

Investigation Of Alternative Hosts And Agronomic Factors Affecting Xanthomonas Vasicola Pv. Vasculorum, Causal Agent Of Bacterial Leaf Streak Of Corn, Terra Marie Hartman

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Xanthomonas vasicola pv. vasculorum, causal agent of bacterial leaf streak of corn, was first reported in the U.S. in 2016 on Nebraska corn leaf samples. Prior to this report, the pathogen had only been reported on corn in South Africa. After the Nebraska report, the pathogen was reported on corn in Argentina, Brazil, and several U.S. states. This pathogen has an extensive host range, which includes sugarcane (Saccharum officinarum), grain sorghum (Sorghum bicolor), palm species (Dictyosperma album, Roystonea regia, and Areca catechu) and broom bamboo (Thysanolaena maxima). Plants commonly found in the U.S. had not been evaluated ...


Biological Activity Of A Tertiary Amine Plant Growth Regulator, Bmve, In Arabidopsis Thaliana And Wheat (Triticum Aestivum), Jaspinder Singh Nov 2018

Biological Activity Of A Tertiary Amine Plant Growth Regulator, Bmve, In Arabidopsis Thaliana And Wheat (Triticum Aestivum), Jaspinder Singh

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Plant growth regulators are synthetic compounds that influence plant growth and development and can increase growth, yield, and nutritive value of food crops. Research in the past has shown that a class of plant growth regulators known collectively as substituted tertiary amines have the potential to increase crop productivity, photosynthetic efficiency, and overall plant vigor. However, earlier efficacy studies that involved spraying plants were sometimes inconsistent or showed only minimal benefits. A new delivery method involving seed application of tertiary amines before sowing has shown promise in field trials for multiple crop species (US patent 9464283) (Yokoyama, Chan, Oyama, & Hov ...


Identification Of Genes/Genomic Regions Controlling Resistance To Biotic And Abiotic Stresses In Synthetic Hexaploid Wheat, Madhav Bhatta Nov 2018

Identification Of Genes/Genomic Regions Controlling Resistance To Biotic And Abiotic Stresses In Synthetic Hexaploid Wheat, Madhav Bhatta

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Synthetic hexaploid wheat (SHW; 2n=6x=42, AABBDD, Triticum aestivumL.) is produced from an interspecific cross between durum wheat (2n=4x=28, AABB, T. turgidumL.) and goat grass (2n=2x=14, DD, AegilopstauschiiCoss.). It is reported to have a considerable amount of genetic diversity and is a potential source of novel alleles controlling abiotic and biotic stresses resistance and improving wheat quality. Therefore, the first study was to understand the genetic diversity and population structure of SHWs and compare the genetic diversity of SHWs with elite bread wheat (BW) cultivars. The result of this study identified a ...


Canavalia Gladiata And Dolichos Lablab Extracts For Sustainable Pest Biocontrol And Plant Nutrition Improvement In El Salvador, Carlos Martinez Oct 2018

Canavalia Gladiata And Dolichos Lablab Extracts For Sustainable Pest Biocontrol And Plant Nutrition Improvement In El Salvador, Carlos Martinez

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Botanical repellents and pesticides are now being rediscovered as new tools for integrated pest management in order to reduce the use of toxic chemicals in crop production. Canavalia gladiata and Dolichos lablab are two Fabaceae very well adapted to farmlands of El Salvador, effective as living barriers and mostly as cover crops, however, they are not yet very well disseminated. This document describes the potential for using the liquid extracts and the dry flour of raw seeds of those plants for economic benefit and practical convenience for pest management in Salvadorian agriculture under field conditions. Seed extracts were useful when ...


Digital Soil Mapping In The Bara District Of Nepal Using Kriging Tool In Arcgis, Dinesh Panday, Bijesh Maharjan, Devraj Chalise, Ram Kumar Shrestha, Bikesh Twanabasu Oct 2018

Digital Soil Mapping In The Bara District Of Nepal Using Kriging Tool In Arcgis, Dinesh Panday, Bijesh Maharjan, Devraj Chalise, Ram Kumar Shrestha, Bikesh Twanabasu

Agronomy & Horticulture -- Faculty Publications

Digital soil mapping has been widely used to develop statistical models of the relationships between environmental variables and soil attributes. This study aimed at determining and mapping the spatial distribution of the variability in soil chemical properties of the agricultural floodplain lands of the Bara district in Nepal. The study was carried out in 23 Village Development Committees with 12,516 ha total area, in the southern part of the Bara district. A total of 109 surface soil samples (0 to 15 cm depth) were collected and analyzed for pH, organic matter (OM), nitrogen (N), phosphorus (P, expressed as P ...


Research Report: Prevalence And Mechanism Of Atrazine Resistance In Waterhemp From Nebraska, Rodrigo Werle, Mithila Jugulam, Greg Kruger, Amaranatha Vennapusa, Felipe Faleco, Bruno Viera, Spencer Samuelson Oct 2018

Research Report: Prevalence And Mechanism Of Atrazine Resistance In Waterhemp From Nebraska, Rodrigo Werle, Mithila Jugulam, Greg Kruger, Amaranatha Vennapusa, Felipe Faleco, Bruno Viera, Spencer Samuelson

Agronomy & Horticulture -- Faculty Publications

Waterhemp is a troublesome summer annual broadleaf weed species that has evolved resistance to glyphosate and other herbicide sites of action (SOA) in Nebraska, including to groups 2 (i.e., Classic, Pursuit, FirstRate), 4 (i.e., 2, 4-D), 5(i.e., atrazine) and 27 (e.g., Callisto, Laudis). The overall objectives of this study were to

  1. Evaluate the eficay of PRE applied atrazine, metribuzin and sulfentrazone to control Nebraska waterhemp populations;
  2. Evaluate the efficacy of POST applied atrazine to control Nebraska waterhemp populations; and
  3. Determine the mechanism of atrazine resistance in Nebraska waterhemp populations.


Analysis Of The Soil Health Of Pastures Over-Seeded With Winter Annuals, Kathleen M. Bridges Oct 2018

Analysis Of The Soil Health Of Pastures Over-Seeded With Winter Annuals, Kathleen M. Bridges

LSU Doctoral Dissertations

Utilizing winter annuals in livestock pastures reduces feed costs of hay, and provides additional vegetative cover that is beneficial to the soil. However, how this practice affects the soil microbial communities has not been well studied. Two sites were included in this study. Both were commercial cattle grazing operations that over-seeded a mixture of grasses, legumes, and brassicas into pastures dominated by bahiagrass (Paspalum notatum). Soil health was assessed using a suite of physical, chemical, and biological properties. Soil physical assessments included bulk density and aggregate stability. Soil chemical assessments included macronutrients, pH, soil organic matter (SOM), total carbon (TC ...


Crop Water Stress Index Of An Irrigated Vineyard In The Central Valley Of California, John H. Prueger, Christopher K. Parry, William P. Kustas, Joseph G. Alfieri, Maria M. Alsina, Héctor Nieto, Tiffany G. Wilson, Lawrence E. Hipps, Martha C. Anderson, Jerry L. Hatfield, Fen Gao, Lynn G. Mckee, Andrew Mcelrone, Nurit Agam, Sebastian A. Los Oct 2018

Crop Water Stress Index Of An Irrigated Vineyard In The Central Valley Of California, John H. Prueger, Christopher K. Parry, William P. Kustas, Joseph G. Alfieri, Maria M. Alsina, Héctor Nieto, Tiffany G. Wilson, Lawrence E. Hipps, Martha C. Anderson, Jerry L. Hatfield, Fen Gao, Lynn G. Mckee, Andrew Mcelrone, Nurit Agam, Sebastian A. Los

Plants, Soils, and Climate Faculty Publications

Water-limiting conditions in many California vineyards necessitate assessment of vine water stress to aid irrigation management strategies and decisions. This study was designed to evaluate the utility of a Crop Water Stress Index (CWSI) using multiple canopy temperature sensors and to study the diurnal signature in the stress index of an irrigated vineyard. A detailed instrumentation package comprised of eddy covariance instrumentation, ancillary surface energy balance components, soil water content sensors and a unique multi-canopy temperature sensor array were deployed in a production vineyard near Lodi, CA. The instrument package was designed to measure and monitor hourly growing season turbulent ...


Soybean Response To Dicamba: Associated Injury Criteria And Development Of A Model To Predict Yield Loss, Matthew Ryan Foster Oct 2018

Soybean Response To Dicamba: Associated Injury Criteria And Development Of A Model To Predict Yield Loss, Matthew Ryan Foster

LSU Doctoral Dissertations

In research conducted using indeterminate soybean [Glycine max (L.) Merr.], fourteen injury criteria observed following dicamba at 0.6 to 280 g ae ha-1 (1/1000 to ½ of 560 g ha-1 use rate) were rated using a scale of 0= no injury, 1= slight, 2= slight to moderate, 3= moderate, 4= moderate to severe, and 5= severe. Greatest crop injury 15 d after treatment (DAT) was observed following dicamba applied at 0.6 to 4.4 g ha-1 at V3/V4 for upper canopy pale leaf margins (3.8 to 4.2) and at R1/R2 ...


Urban Agriculture And Small Farm Water Use: Case Studies And Trends From Cache Valley, Utah, Tyler Pratt, L. Niel Allen, David E. Rosenberg, Andrew A. Keller, Kelly Kopp Oct 2018

Urban Agriculture And Small Farm Water Use: Case Studies And Trends From Cache Valley, Utah, Tyler Pratt, L. Niel Allen, David E. Rosenberg, Andrew A. Keller, Kelly Kopp

Publications

The landscape of water in Utah is changing due to population growth, conversion of agricultural land to urban development, and increasing awareness of water scarcity. At the same time, Utah is experiencing a growing number of urban and small farms, but knowledge of water use in this sector is limited. Better understanding of what occurs at the field level on urban and small farms can aid state water use estimates and conservation efforts, and assist farmers in moving towards wiser water management. For the 2015 growing season, we performed irrigation evaluations for 24 urban and small farms in Cache Valley ...


High Density Genetic Mapping Of Fusarium Head Blight Resistance Qtl In Tetraploid Wheat, Ehsan Sari, Samia Berraies, Ron E. Knox, Asheesh K. Singh, Yuefeng Ruan, Richard D. Cuthbert, Curtis J. Pozniak, Maria Antonia Henriquez, Santosh Kumar, Andrew J. Burt, Amidou N'Diaye, David J. Konkin, Adrian L. Cabral, Heather L. Campbell, Krystalee Wiebe, Janet Condie, Prabhath Lokuruge, Brad Meyer, George Fedak, John M. Clarke, Daryl J. Somers, Perre R. Fobert Oct 2018

High Density Genetic Mapping Of Fusarium Head Blight Resistance Qtl In Tetraploid Wheat, Ehsan Sari, Samia Berraies, Ron E. Knox, Asheesh K. Singh, Yuefeng Ruan, Richard D. Cuthbert, Curtis J. Pozniak, Maria Antonia Henriquez, Santosh Kumar, Andrew J. Burt, Amidou N'Diaye, David J. Konkin, Adrian L. Cabral, Heather L. Campbell, Krystalee Wiebe, Janet Condie, Prabhath Lokuruge, Brad Meyer, George Fedak, John M. Clarke, Daryl J. Somers, Perre R. Fobert

Agronomy Publications

Breeding for Fusarium head blight (FHB) resistance in durum wheat is complicated by the quantitative trait expression and narrow genetic diversity of available resources. High-density mapping of the FHB resistance quantitative trait loci (QTL), evaluation of their co-localization with plant height and maturity QTL and the interaction among the identified QTL are the objectives of this study. Two doubled haploid (DH) populations, one developed from crosses between Triticum turgidum ssp. durum lines DT707 and DT696 and the other between T. turgidum ssp. durum cv. Strongfield and T. turgidum ssp. carthlicum cv. Blackbird were genotyped using the 90K Infinium iSelect chip ...


Aac Viewfield Hard Red Spring Wheat, R. D. Cuthbert, R. M. Depauw, A. K. Singh, B. Mccallum, T. Fetch Oct 2018

Aac Viewfield Hard Red Spring Wheat, R. D. Cuthbert, R. M. Depauw, A. K. Singh, B. Mccallum, T. Fetch

Agronomy Publications

AAC Viewfield hard red spring wheat (Triticum aestivum L.) has grain yield significantly higher than the check cultivars Katepwa and Lillian and is similar to Carberry. AAC Viewfield matures significantly later than Katewpa and Lillian but is similar to Carberry. AAC Viewfield has an awned spike, a low lodging score indicative of strong straw, and significantly shorter plant stature than all checks. AAC Viewfield expressed resistance to prevalent races of yellow rust and stem rust, moderate resistance to leaf rust and common bunt, and intermediate resistance to Fusarium head blight. AAC Viewfield has quality attributes within the range of the ...


Overexpression Of The Sorghum Bicolor Sbccoaomt Alters Cell Wall Associated Hydroxycinnamoyl Groups, Hannah M. Tetreault, Erin D. Scully, Tammy Gries, Nathan A. Palmer, Deanna L. Funnell-Harris, Bruce S. Dien, Gautam Sarath, Thomas E. Clemente, Scott E. Sattler Oct 2018

Overexpression Of The Sorghum Bicolor Sbccoaomt Alters Cell Wall Associated Hydroxycinnamoyl Groups, Hannah M. Tetreault, Erin D. Scully, Tammy Gries, Nathan A. Palmer, Deanna L. Funnell-Harris, Bruce S. Dien, Gautam Sarath, Thomas E. Clemente, Scott E. Sattler

Agronomy & Horticulture -- Faculty Publications

Sorghum (Sorghum bicolor) is a drought tolerant crop, which is being developed as a bioenergy feedstock. The monolignol biosynthesis pathway is a major focus for altering the abundance and composition of lignin. Caffeoyl coenzyme-A O-methyltransferase (CCoAOMT) is an S-adenosyl methionine (SAM)-dependent O-methyltransferase that methylates caffeoyl-CoA to generate feruloyl-CoA, an intermediate required for the biosynthesis of both G- and S-lignin. SbCCoAOMT was overexpressed to assess the impact of increasing the amount of this enzyme on biomass composition. SbCCoAOMT overexpression increased both soluble and cell wall-bound (esterified) ferulic and sinapic acids, however lignin concentration and its composition (S ...


Elucidating Sorghum Biomass, Nitrogen And Chlorophyll Contents With Spectral And Morphological Traits Derived From Unmanned Aircraft System, Jiating Li, Arun-Narenthiran Veeranampalayam-Sivakumar, Daniel P. Schachtman Oct 2018

Elucidating Sorghum Biomass, Nitrogen And Chlorophyll Contents With Spectral And Morphological Traits Derived From Unmanned Aircraft System, Jiating Li, Arun-Narenthiran Veeranampalayam-Sivakumar, Daniel P. Schachtman

Agronomy & Horticulture -- Faculty Publications

Unmanned aircraft systems (UAS) provide an efficient way to phenotype cropmorphology with spectral traits such as plant height, canopy cover and various vegetation indices (VIs) providing information to elucidate genotypic responses to the environment. In this study, we investigated the potential use of UAS-derived traits to elucidate biomass, nitrogen and chlorophyll content in sorghum under nitrogen stress treatments. A nitrogen stress trial located in Nebraska, USA, contained 24 different sorghum lines, 2 nitrogen treatments and 8 replications, for a total of 384 plots. Morphological and spectral traits including plant height, canopy cover and various VIs were derived from UAS flights ...


Summaries Of Arkansas Cotton Research 2017, Fred Bourland Oct 2018

Summaries Of Arkansas Cotton Research 2017, Fred Bourland

Research Series

No abstract provided.


Legacy Effects Of Long-Term Nitrogen Fertilizer Application On The Fate Of Nitrogen Fertilizer Inputs In Continuous Maize, Hanna J. Poffenbarger, John E. Sawyer, Daniel W. Barker, Daniel C. Olk, Johan Six, Michael J. Castellano Oct 2018

Legacy Effects Of Long-Term Nitrogen Fertilizer Application On The Fate Of Nitrogen Fertilizer Inputs In Continuous Maize, Hanna J. Poffenbarger, John E. Sawyer, Daniel W. Barker, Daniel C. Olk, Johan Six, Michael J. Castellano

Agronomy Publications

Nitrogen fertilizer management can impact soil organic C (SOC) stocks in cereal-based cropping systems by regulating crop residue inputs and decomposition rates. However, the impact of long-term N fertilizer management, and associated changes in SOC quantity and quality, on the fate of N fertilizer inputs is uncertain. Using two 15-year N fertilizer rate experiments on continuous maize (Zea mays L.) in Iowa, which have generated gradients of SOC, we evaluated the legacy effects of N fertilizer inputs on the fate of added N. Across the historical N fertilizer rates, which ranged from 0 to 269 kg N ha−1 yr ...


The Effect Of Ingredient-Specific Calorie Information On Calories Ordered, Christopher R. Gustafson, Eliana Zeballos Sep 2018

The Effect Of Ingredient-Specific Calorie Information On Calories Ordered, Christopher R. Gustafson, Eliana Zeballos

Agronomy & Horticulture -- Faculty Publications

Providing calorie labeling is a widely used strategy to combat obesity. However, there is little evidence that the availability of calorie information at food-away-from-home establishments has an effect on food choices. Listing calorie information for each ingredient, though, may allow customers to avoid high-calorie items that add little to their enjoyment. Data from a natural experiment were used to compare total calories ordered before and after the provision of per-ingredient versus for build-your-own sandwiches, and per-sandwich for pre-defined sandwiches, at a supermarket sandwich counter. Sandwich order slips from a Lincoln, Neb. supermarket were collected from December 15, 2016 to February ...


Multi-Objective Optimized Genomic Breeding Strategies For Sustainable Food Improvement, Deniz Akdemir, William D, Beavis, Roberto Fritsche-Neto, Asheesh K. Singh, Julio Isidro-Sánchez Sep 2018

Multi-Objective Optimized Genomic Breeding Strategies For Sustainable Food Improvement, Deniz Akdemir, William D, Beavis, Roberto Fritsche-Neto, Asheesh K. Singh, Julio Isidro-Sánchez

Agronomy Publications

The purpose of breeding programs is to obtain sustainable gains in multiple traits while controlling the loss of genetic variation. The decisions at each breeding cycle involve multiple, usually competing, objectives; these complex decisions can be supported by the insights that are gained by applying multi-objective optimization principles to breeding. The discussion in this manuscript includes the definition of several multi-objective optimized breeding approaches within the phenotypic or genomic breeding frameworks and the comparison of these approaches with the standard multi-trait breeding schemes such as tandem selection, independent culling and index selection. Proposed methods are demonstrated with two empirical data ...


A Novel Multirobot System For Plant Phenotyping, Tianshuang Gao, Hamid Emadi, Homagni Saha, Jiaoping Zhang, Alec Lofquist, Arti Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Asheesh K. Singh, Sourabh Bhattacharya Sep 2018

A Novel Multirobot System For Plant Phenotyping, Tianshuang Gao, Hamid Emadi, Homagni Saha, Jiaoping Zhang, Alec Lofquist, Arti Singh, Baskar Ganapathysubramanian, Soumik Sarkar, Asheesh K. Singh, Sourabh Bhattacharya

Mechanical Engineering Publications

Phenotypic studies require large datasets for accurate inference and prediction. Collecting plant data in a farm can be very labor intensive and costly. This paper presents the design, architecture (hardware and software) and deployment of a multi-robot system for row crop field data collection. The proposed system has been deployed in a soybean research farm at Iowa State University.


Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis, Navreet K. Mahal, Michael J. Castellano, Fernando E. Miguez Sep 2018

Conservation Agriculture Practices Increase Potentially Mineralizable Nitrogen: A Meta-Analysis, Navreet K. Mahal, Michael J. Castellano, Fernando E. Miguez

Agronomy Publications

Potentially mineralizable nitrogen (PMN) is considered an important indicator of soil health. Cropping systems management can affect PMN. However, the effect size and relationship with crop yield across specific management practices remain uncertain. We conducted a quantitative review to understand how conservation agriculture management practices affect PMN including N fertilizer application, cropping system diversity, and tillage system as well as the relationship of crop yield with PMN. Data were extracted from 43 studies published in peer-reviewed journals, providing 494 paired comparisons of PMN and 26 paired comparisons of PMN and yield across selected crop management practices. In our meta-analysis, the ...


Phylogenomic Evidence For Ancient Recombination Between Plastid Genomes Of The Cupressus-Juniperus-Xanthocyparis Complex (Cupressaceae), Andan Zhu, Weishu Fan, Robert P. Adams, Jeffrey P. Mower Sep 2018

Phylogenomic Evidence For Ancient Recombination Between Plastid Genomes Of The Cupressus-Juniperus-Xanthocyparis Complex (Cupressaceae), Andan Zhu, Weishu Fan, Robert P. Adams, Jeffrey P. Mower

Agronomy & Horticulture -- Faculty Publications

Background: Phylogenetic relationships among Eastern Hemisphere cypresses, Western Hemisphere cypresses, junipers, and their closest relatives are controversial, and generic delimitations have been in flux for the past decade. To address relationships and attempt to produce a more robust classification, we sequenced 11 new plastid genomes (plastomes) from the five variously described genera in this complex (Callitropsis, Cupressus, Hesperocyparis, Juniperus, and Xanthocyparis) and compared them with additional plastomes from diverse members of Cupressaceae.

Results: Phylogenetic analysis of protein-coding genes recovered a topology in which Juniperus is sister to Cupressus, whereas a tree based on whole plastomes indicated that the Callitropsis-Hesperocyparis ...


Mobile Elements Shape Plastome Evolution In Ferns, Tanner A. Robison, Amanda L. Grusz, Paul G. Wolf, Jeffrey P. Mower, Blake D. Fauskee, Karla Sosa, Eric Schuettpelz Aug 2018

Mobile Elements Shape Plastome Evolution In Ferns, Tanner A. Robison, Amanda L. Grusz, Paul G. Wolf, Jeffrey P. Mower, Blake D. Fauskee, Karla Sosa, Eric Schuettpelz

Agronomy & Horticulture -- Faculty Publications

Plastid genomes display remarkable organizational stability over evolutionary time. From green algae to angiosperms, most plastid genomes are largely collinear, with only a few cases of inversion, gene loss, or, in extremely rare cases, gene addition. These plastome insertions are mostly clade-specific and are typically of nuclear or mitochondrial origin. Here, we expand on these findings and present the first family-level survey of plastome evolution in ferns, revealing a novel suite of dynamic mobile elements. Comparative plastome analyses of the Preridaceae expose several mobile open reading frames that vary in sequence length, insertion site, and configuration among sampled taxa. Even ...