Agronomy and Crop Sciences Commons^™

Comparing Water Quality For Aquaponics Systems With Different Solids Removal Methods And Biofilter Media, And Effluent Output To Grow Beds, John W. Cutt, Heather M. Joesting, Brigette A. Brinton

Honors College Theses

Aquaponics is a closed-loop, sustainable method of food production that combines fish and plant production. This method of agriculture has the potential to bring fresh, local food to food-insecure areas, but challenges remain due to high operating costs. In order to develop a strong aquaponics industry, the creation of the most efficient system designs will be critical in optimizing production. This study’s purpose was to compare water quality between two aquaponics system designs that differ in filtration and solid removal methods. System 1 used a sock filter for solid removal and Kaldnes media for biofiltration while System 2 used a …

Metabolite Profiling Of Ganoderma-Infected Oil Palm Tree Grown On Ultisol And Oxisol Soil, Ahmad Muhamad Fadhil

Student Works (2020-2029)

The oil palm industry is a pillar of the Malaysian economy and plays a pivotal role in feeding and fueling a growing global population. In 2018, oil palm contributed 37.9% or RM37.7 billion to the country's' Gross Domestic Products (GDP) of agriculture sector. Despite achieving significant achievements in the industry, Ganoderma sp. infection that cause basal stem rot (BSR) and upper stem rot (USR) disease are considered a threat. The palm oil industry is expected to experience significant losses, thereby affecting yield production and ultimately the dead of trees. Some factors have been reported to affect the occurrence of the …

Discovery: The Student Journal Of Dale Bumpers College Of Agricultural, Food And Life Sciences - Volume 21 2020, Several Authors

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

A Review Of Technologies For Malt Flour And Sourdough From Brewery Spent Grain, Zachary Christman

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The utilization of brewer's spent grain for the production of malt flour is the focus of this article. The reader is presented with superheated steam and extrusion as technologies to reduce mycotoxin contamination and improve shelf life. Another option is the fermentation of brewer's spent grain with a cereal grade lactic acid bacteria for the production of sourdough bread. Milling of the brewer's spent grain for the production of bread is also covered.

A Justification For Continued Management Of Turfgrass During Economic Contraction, James T. Brosnan, Ambika Chandra, Roch E. Gaussoin, Alec Kowalewski, Bernd Leinauer, Frank S. Rossi, Douglas J. Soldat, John C. Stier, J. Bryan Unruh

Department of Agronomy and Horticulture: Faculty Publications

A novel coronavirus, termed COVID-19, spread worldwide and become a global pandemic in 2020. Forecasts show that COVID-19 will cause substantial economic contraction affecting almost every industry. Managed turfgrass, particularly in urban settings, has many positive societal and environmental benefits. In a contracted economy, will resources be available to manage turfgrass to achieve these benefits? In this paper, we outline the benefits of managed turfgrass on golf courses, playing fields, recreational parks, and urban landscapes to assist decision makers with resource allocation in the COVID-19 era.

Soil Sample Timing, Nitrogen Fertilization, And Incubation Length Influence Anaerobic Potentially Mineralizable Nitrogen, Jason Clark, Kristen S. Veum, Fabián G. Fernández, Newell R. Kitchen, James J. Camberato, Paul Carter, Richard Ferguson, David W. Franzen, Daniel E. Kaiser, Carrie A. M. Laboski, Emerson Nafziger, Carl J. Rosen, John E. Sawyer, John F. Shanahan

Department of Agronomy and Horticulture: Faculty Publications

Understanding the variables that affect the anaerobic potentially mineralizable N (PMNan) test should lead to a standard procedure of sample collection and incubation length, improving PMNan as a tool in corn (Zea mays L.) N management. We evaluated the effect of soil sample timing (preplant and V5 corn development stage [V5]), N fertilization (0 and 180 kg ha−1) and incubation length (7, 14, and 28 d) on PMNan (0–30 cm) across a range of soil properties and weather conditions. Soil sample timing, N fertilization, and incubation length affected PMNan differently based on soil and weather conditions. Preplant vs. V5 PMNan …

Cover Crops And Weed Suppression In The U.S. Midwest: A Meta-Analysis And Modeling Study, Virginia Nicholas, Rafael Martinez-Feria, David Weisberger, Sarah Carlson, B. Basso, Andrea Basche

Department of Agronomy and Horticulture: Faculty Publications

In addition to soil health and conservation benefits, cover crops (CCs) may offer weed control in the midwestern United States, but individual studies report vary- ing effects. We conducted a meta-analysis of studies measuring weed biomass (WBIO) or density (WDEN) in paired CC and no-cover treatments in corn (Zea mays L.)–soybean [Glycine max (L.) Merr] rotations in the U.S. Midwest. Fifteen studies provided 123 paired comparisons of WBIO and 119 of WDEN. Only grass CCs significantly reduced WBIO, while no CC reduced WDEN. We found no evidence CC management factors (e.g., termination method) directly affected out- comes. Our dataset showed …

Quantifying On‐Farm Nitrous Oxide Emission Reductions In Food Supply Chains, A.J. Eagle, E. Mclellan, E.M. Brawner, M.H. Chantigny, Eric A. Davidson, J.B. Dickey, Bruce A. Linquist, T.M. Maaz, D.E. Pelster, Cameron M. Pittelkow, C. Van Kessel, T.J. Vyn, K. G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Reducing nitrous oxide (N2O) emissions from agriculture is critical to limiting future global warming. In response, a growing number of food retailers and manufacturers have committed to reducing N2O emissions from their vast networks of farmer suppliers by providing technical assistance and financial incentives. A key challenge for such companies is demonstrating that their efforts are leading to meaningful progress toward their climate mitigation commitments. We show that a simplified version of soil surface nitrogen (N) balance—or partial N balance—the difference between N inputs to and outputs

from a farm field (fertilizer N minus crop N), is a robust indicator …

Woody Plant Encroachment And The Sustainability Of Priority Conservation Areas, Dillon Fogarty, Caleb P. Roberts, Daniel R. Uden, Victoria M. Donovan, Craig R. Allen, David E. Naugle, Matthew O. Jones, Brady W. Allred, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

Woody encroachment is a global driver of grassland loss and management to counteract encroachment represents one of the most expensive conservation practices implemented in grasslands. Yet, outcomes of these practices are often unknown at large scales and this constrains practitioner’s ability to advance conservation. Here, we use new monitoring data to evaluate outcomes of grassland conservation on woody encroachment for Nebraska’s State Wildlife Action Plan, a statewide effort that targets management in Biologically Unique Landscapes (BULs) to conserve the state’s natural communities. We tracked woody cover trajectories for BULs and compared BUL trajectories with those in non-priority landscapes (non-BULs) to …

Strategic Switchgrass (Panicum Virgatum) Production Within Row Cropping Systems: Regional-Scale Assessment Of Soil Erosion Loss And Water Runoff Impacts, Enheng Wang, R. M. Cruse, Bharat Sharma-Acharya, Daryl E. Herzmann, Brian K. Gelder, David E. James, Dennis C. Flanagan, Humberto Blanco-Canqui, Robert B. Mitchell, David Laird

Department of Agronomy and Horticulture: Faculty Publications

A strong need exists for tools to assess the efficacy of conservation practices across large regions supporting informed policy decisions that may lead to better soil and water conservation while optimizing agricultural production options. Perennial warm-season grasses (WSGs) such as switchgrass (Panicum virgatum), can be grown on marginally productive and/or environmentally sensitive lands to meet growing bioenergy demands while reducing water runoff and soil erosion compared to current row crop systems. Quantifying the soil and water conservation effects of WSG when strategically placed on the landscape would help support decisions favoring both economic and environmental benefits. We used the Daily …

Soil Aggregation As Affected By Application Of Diverse Organic Materials, Maman Garba, Charles S. Wortmann, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

Application of organic materials can amend soil for improved water infiltration and reduced erodibility with effects varying with soil properties and the organic amendment type and rate. The effects of four livestock manures, three municipal biosolids, and one industrial by-product on dry and wet soil aggregate stability were evaluated at six sites in Nebraska. The amendments had similar C/N ratios but the biosolids had relatively high concentrations of lignin and cellulose. Soil organic matter (SOM) ranged from 21 to 65 g kg−1 and soils were silty clay loam, silt loam, or loamy sand. Soil was sampled for the 0- to …

Benchmarking The Agronomic Performance Of Biodegradable Mulches Against Polyethylene Mulch Film: A Meta‐Analysis, Mauro B.D. Tofanelli, Samuel E. Wortman

Department of Agronomy and Horticulture: Faculty Publications

Growers are interested in biodegradable alternatives to petroleum‐based polyethylene mulch film (PEM). However, many growers cite limited knowledge about biodegradable mulch films (BDMs) as a significant barrier to adoption. Agronomic field tests of BDMs are often limited temporally or spatially, and the variability of performance results relative to PEM may be contributing to this perceived knowledge gap. Our objective was to use data available in the scientific literature to provide the first quantitative performance benchmark of BDMs against PEM. We extracted data from 66 articles for meta‐analysis. Response ratios were calculated for comparison of BDMs relative to black PEM, and …

Transformative Education In Agroecology: Student, Teacher, And Client Involvement In Co-Learning, Charles A. Francis, Anna Marie Nicolaysen, Geir Lieblein, Tor Arvid Breland

Department of Agronomy and Horticulture: Faculty Publications

Educational methods have evolved rapidly in agroecology, which is a complex and holistic field without a long history or the formal tradition of any single academic discipline. Definitions of agroecology have evolved from its initial conception as a marriage of agriculture with ecology, to an aggregation of different paths including science, practices, and movements, and recently as a broad appreciation of the ecology of food systems. In contrast with traditional courses that begin with a history of the discipline and review the contributions of early leaders, we have embraced phenomenology to firmly establish roots in students’ learning through their experiences …

Wheat Growth Monitoring And Yield Estimation Based On Multi-Rotor Unmanned Aerial Vehicle, Zhaopeng Fu, Jie Jang, Yang Gao, Brian Krienke, Meng Wang, Kaitai Zhong, Qiang Cao, Yongchao Tian, Yan Zhu, Weixing Cao, Xiaojun Liu

Department of Agronomy and Horticulture: Faculty Publications

Leaf area index (LAI) and leaf dry matter (LDM) are important indices of crop growth. Real-time, nondestructive monitoring of crop growth is instructive for the diagnosis of crop growth and prediction of grain yield. Unmanned aerial vehicle (UAV)-based remote sensing is widely used in precision agriculture due to its unique advantages in flexibility and resolution. This study was carried out on wheat trials treated with different nitrogen levels and seeding densities in three regions of Jiangsu Province in 2018–2019. Canopy spectral images were collected by the UAV equipped with a multi-spectral camera during key wheat growth stages. To verify the …

Gwas: Fast-Forwarding Gene Identification And Characterization In Temperate Cereals: Lessons From Barley – A Review, Ahmad M. Alqudah, Ahmed Sallam, P. Stephen Baenziger, Andreas Börner

Department of Agronomy and Horticulture: Faculty Publications

Understanding the genetic complexity of traits is an important objective of small grain temperate cereals yield and adaptation improvements. Bi-parental quantitative trait loci (QTL) linkage mapping is a pow- erful method to identify genetic regions that co-segregate in the trait of interest within the research pop- ulation. However, recently, association or linkage disequilibrium (LD) mapping using a genome-wide association study (GWAS) became an approach for unraveling the molecular genetic basis underlying the natural phenotypic variation. Many causative allele(s)/loci have been identified using the power of this approach which had not been detected in QTL mapping populations. In barley (Hordeum …

The State Of Sustainable Agriculture And Agroecology Research And Impacts: A Survey Of U.S. Scientists, Marcia Delonge, Tali Robbins, Andrea D. Basche, Lindsey Haynes-Maslow

Department of Agronomy and Horticulture: Faculty Publications

A growing body of research suggests that although sustainable agriculture, particularly agroecology, can address challenges such as those related to climate change, ecosystem services, food insecurity, and farmer livelihoods, the transition to such systems remains limited. To gain insight into the state of U.S. sustainable agriculture and agroecology, we developed a 28-question mixed-method survey that was administered to scientists in these fields. Respondents (N=168) represented diverse locations, institutions, and career stages. They offered varied definitions of sustainable agriculture, with 40% considering economic and social well-being to be core components. Respondents identified the amount and duration of public research …

Dicamba Retention In Commercial Sprayers Following Triple Rinse Cleanout Procedures, And Soybean Response To Contamination Concentrations, Frances B. Browne, Xiao Li, Katilyn J. Price, Jianping Wang, Yi Wang, Greg R. Kruger, Jeff Golus, Gabrielle De Castro Macedo, Bruno C. Vieira, Tyler Sandlin

Department of Agronomy and Horticulture: Faculty Publications

The commercial launch of dicamba‐tolerant (DT) crops has resulted in increased dicamba usage and a high number of dicamba off‐target movement complaints on sensitive soybeans (Glycine max L.). Dicamba is a synthetic auxin and low dosages as 0.028 g ae ha−1 can induce injury on sensitive soybean. Tank contamination has been identified as one of the sources for unintended sensitive crop exposure. The labels of new dicamba formulations require a triple rinse cleanout procedure following applications. Cleanout efficacy might vary based on the sprayer type and procedure followed. This study was performed to quantify dicamba retention in commercial sprayers and …

Prediction Strategies For Leveraging Information Of Associated Traits Under Single- And Multi-Trait Approaches In Soybeans, Reyna Persa, Arthur Bernardeli, Diego Jarquin

Department of Agronomy and Horticulture: Faculty Publications

The availability of molecular markers has revolutionized conventional ways to improve genotypes in plant and animal breeding through genome-based predictions. Several models and methods have been developed to leverage the genomic information in the prediction context to allow more efficient ways to screen and select superior genotypes. In plant breeding, usually, grain yield (yield) is the main trait to drive the selection of superior genotypes; however, in many cases, the information of associated traits is also routinely collected and it can potentially be used to enhance the selection. In this research, we considered different prediction strategies to leverage the information …

Rhizosphere Microbiome Of Arid Land Medicinal Plants And Extra Cellular Enzymes Contribute To Their Abundance, Abdul Latif Khan, Sajjad Asaf, Raeid M. M. Abed, Yen Ning Chai, Ahmed N. Al-Rawahi, Tupan Kumar Mohanta, Ahmed Al-Rawahi, Daniel P. Schachtman, Ahmed Al-Harrasi

Department of Agronomy and Horticulture: Faculty Publications

Revealing the unexplored rhizosphere microbiome of plants in arid environments can help in understanding their interactions between microbial communities and plants during harsh growth conditions. Here, we report the first investigation of rhizospheric fungal and bacterial communities of Adenium obesum, Aloe dhufarensis and Cleome austroarabica using next-generation sequencing approaches. A. obesum and A. dhufarensis grows in dry tropical and C. austroarabica in arid conditions of Arabian Peninsula. The results indicated the presence of 121 fungal and 3662 bacterial operational taxonomic units (OTUs) whilst microbial diversity was significantly high in the rhizosphere of A. obesum and A. dhufarensis and low …

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

Department of Agronomy and 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 ha of …

Leveraging Genome-Enabled Growth Models To Study Shoot Growth Responses To Water Deficit In Rice, Malachy T. Campbell, Alexandre Grondin, Harkamal Walia, Gota Morota

Department of Agronomy and Horticulture: Faculty Publications

lucidating genotype-by-environment interactions and partitioning its contribution to phenotypic variation remains a challenge for plant scientists. We propose a framework that utilizes genome-wide markers to model genotype-specific shoot growth trajectories as a function of time and soil water availability. A rice diversity panel was phenotyped daily for 21 d using an automated, high-throughput image-based, phenotyping platform that enabled estimation of daily shoot biomass and soil water content. Using these data, we modeled shoot growth as a function of time and soil water content, and were able to determine the time point where an inflection in the growth trajectory occurred. We …

Training Future Agriculture Professionals In Landowner–Tenant Conservation Decision-Making, Andrea Basche, Angie Carter

Department of Agronomy and Horticulture: Faculty Publications

The landowner–tenant relationship is important to the implementation of conser- vation on agricultural lands. Women own or co-own a significant portion of U.S. farmland yet are underrepresented in conservation research. The next generation of agriculture professionals can benefit from first-hand experience in assisting women landowners and their tenants in navigating the complexities of conser- vation decision-making. This article analyzes undergraduate student perceptions of landowner–tenant relationships in conservation management through their engagement in case studies with women landowner–tenant pairs in the Western Corn Belt. Student groups were asked to complete a management improvement plan that both incorporated the agronomic and conservation …

Is Allelopathy From Winter Cover Crops Affecting Row Crops?, Katja Koehler-Cole, Sydney Everhart, Yan Gu, Christopher A. Proctor, Margarita Marroquin-Guzman, Daren Redfearn, Roger W. Elmore

Department of Agronomy and Horticulture: Faculty Publications

Cover crops (CC) have been explored in corn (Zea mays L.), cotton (Gossypium hirsutum L.), soybean [Glycine max (L.) Merr.], and wheat (Triticum aestivum L.) systems for their allelopathic potential to control weeds. However, allelopathic compounds may negatively affect these row crops by reducing germination, emergence, and grain yields. We reviewed studies that document allelopathic effects of CC on subsequent row crops in field and laboratory settings. We summarize the influence of CC management, including biomass production, planting and termination timing on allelochemical quantity. Our review found few studies documenting allelopathic effects of CC on row …

Winter Cover Crop Root Biomass Yield In Corn And Soybean Systems, Sabrina J. Ruis, Humberto Blanco-Canqui, Katja Koehler-Cole, Paul J. Jasa, G. Slater, Roger W. Elmore, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Cover crop (CC) roots are critical for soil ecosystem service delivery including soil stabilization, C and nutrient cycling, soil health improvement, and others. However, most CC studies only evaluate CC aboveground biomass yield, neglecting the belowground portion of the plant. The objectives of this study were to quantify the impacts of (a) CC planting (pre- and post-harvest) dates and (b) early (2–4 wk before main crop planting) and late (at main crop planting) CC termination with and without corn (Zea mays L.) residue removal on root biomass yield. We assessed the effects of CC planting or termination dates on root …

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas Clemente, Paul Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Drought stress is the major limiting factor in agriculture. Wheat, which is the most widely grown crop in the world, is predominantly cultivated in drought-prone rainfed environments. Since roots play a critical role in water uptake, root response to water limitations is an important component for enhancing wheat adaptation. In an effort to discover novel genetic sources for improving wheat adaptation, we characterized a wheat translocation line with a chromosomal segment from Agropyron elongatum, a wild relative of wheat, which unlike common wheat maintains root growth under limited-water conditions. By exploring the root transcriptome data, we found that reduced …

The Lateral Root Density Gene Regulates Root Growth During Water Stress In Wheat, Dante F. Placido, Jaspreet Sandhu, Shirley Sato, Natalya Nersesian, Truyen Quach, Thomas E. Clemente, Paul E. Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Drought stress is the major limiting factor in agriculture. Wheat, which is the most widely grown crop in the world, is predominantly cultivated in drought-prone rainfed environments. Since roots play a critical role in water uptake, root response to water limitations is an important component for enhancing wheat adaptation. In an effort to discover novel genetic sources for improving wheat adaptation, we characterized a wheat translocation line with a chromosomal segment from Agropyron elongatum, a wild relative of wheat, which unlike common wheat maintains root growth under limited-water conditions. By exploring the root transcriptome data, we found that reduced …

Multi-Trait Random Regression Models Increase Genomic Prediction Accuracy For A Temporal Physiological Trait Derived From High-Throughput Phenotyping, Toshimi Baba, Mehdi Momen, Malachy T. Campbell, Harkamal Walia, Gota Morota

Department of Agronomy and Horticulture: Faculty Publications

Random regression models (RRM) are used extensively for genomic inference and predic- tion of time-valued traits in animal breeding, but only recently have been used in plant sys- tems. High-throughput phenotyping (HTP) platforms provide a powerful means to collect high-dimensional phenotypes throughout the growing season for large populations. How- ever, to date, selection of an appropriate statistical genomic framework to integrate multiple temporal traits for genomic prediction in plants remains unexplored. Here, we demonstrate the utility of a multi-trait RRM (MT-RRM) for genomic prediction of daily water usage (WU) in rice (Oryza sativa) through joint modeling with shoot …

Soil Carbon Increased By Twice The Amount Of Biochar Carbon Applied After 6 Years: Field Evidence Of Negative Priming, Humberto Blanco-Canqui, David A. Laird, Emily A. Heaton, Samuel Rathke, Bharat Sharma Acharya

Department of Agronomy and Horticulture: Faculty Publications

Applying biochar to agricultural soils has been proposed as a means of sequester-ing carbon (C) while simultaneously enhancing soil health and agricultural sustain-ability. However, our understanding of the long-term effects of biochar and annual versus perennial cropping systems and their interactions on soil properties under field conditions is limited. We quantified changes in soil C concentration and stocks, and other soil properties 6 years after biochar applications to corn (Zea mays L.) and dedicated bioenergy crops on a Midwestern US soil. Treatments were as fol-lows: no-till continuous corn, Liberty switchgrass (Panicum virgatum L.), and low-diversity prairie grasses, 45% big bluestem …

Transforming Unmanned Aerial Vehicle (Uav) And Multispectral Sensor Into A Practical Decision Support System For Precision Nitrogen Management In Corn, Laura J. Thompson, Laila A. Puntel

Department of Agronomy and Horticulture: Faculty Publications

Determining the optimal nitrogen (N) rate in corn remains a critical issue, mainly due to unaccounted spatial (e.g., soil properties) and temporal (e.g., weather) variability. Unmanned aerial vehicles (UAVs) equipped with multispectral sensors may provide opportunities to improve N management by the timely informing of spatially variable, in-season N applications. Here, we developed a practical decision support system (DSS) to translate spatial field characteristics and normalized difference red edge (NDRE) values into an in-season N application recommendation. On-farm strip-trials were established at three sites over two years to compare farmer’s traditional N management to a split-application N management guided by …

Land-Use Type As A Driver Of Large Wildfire Occurrence In The U.S. Great Plains, Victoria M. Donovan, Carissa L. Wonkka, David A. Wedin, Dirac Twidwell

Department of Agronomy and Horticulture: Faculty Publications

Wildfire activity has surged in North America’s temperate grassland biome. Like many biomes, this system has undergone drastic land-use change over the last century; however, how various land-use types contribute to wildfire patterns in grassland systems is unclear. We determine if certain land-use types have a greater propensity for large wildfire in the U.S. Great Plains and how this changes given the percentage of land covered by a given land-use type. Almost 90% of the area burned in the Great Plains occurred in woody and grassland land-use types. Although grassland comprised the greatest area burned by large wildfires, woody vegetation …