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Long-Term Impact Of Poultry Manure On Crop Yield, Soil And Water Quality, And Crop Revenue, Natasha L. Hoover, Ji Yeow Law, Leigh Ann M. Long, Rameshwar S. Kanwar, Michelle L. Soupir Dec 2019

Long-Term Impact Of Poultry Manure On Crop Yield, Soil And Water Quality, And Crop Revenue, Natasha L. Hoover, Ji Yeow Law, Leigh Ann M. Long, Rameshwar S. Kanwar, Michelle L. Soupir

Agricultural and Biosystems Engineering Publications

A long-term poultry manure fertilizer study was initiated in 1998 and continued until 2009 under corn-soybean (CS) rotation. To match changing landscape trends, the plots were switched to continuous corn (CC) from 2010 to 2017. In both CS and CC phases, poultry manure (PM) was applied at the crop rotation recommended agronomic N rate and either half (CC phase) or double (CS phase) the recommended rate. Urea-ammonium nitrate (UAN) was applied to comparison plots at the crop recommended application rate (168 kg N ha−1 and 224 kg N ha−1 for the CS and CC phases, respectively) throughout the ...


Assessing Plant Performance In The Enviratron, Yin Bao, Scott Zarecor, Dylan Shah, Taylor Tuel, Darwin A. Campbell, Antony V. E. Chapman, David Imberti, Daniel Kiekhaefer, Henry Imberti, Thomas Lubberstedt, Yanhai Yin, Dan Nettleton, Carolyn J. Lawrence-Dill, Steven A. Whitham, Lie Tang, Stephen H. Howell Dec 2019

Assessing Plant Performance In The Enviratron, Yin Bao, Scott Zarecor, Dylan Shah, Taylor Tuel, Darwin A. Campbell, Antony V. E. Chapman, David Imberti, Daniel Kiekhaefer, Henry Imberti, Thomas Lubberstedt, Yanhai Yin, Dan Nettleton, Carolyn J. Lawrence-Dill, Steven A. Whitham, Lie Tang, Stephen H. Howell

Agricultural and Biosystems Engineering Publications

Background: Assessing the impact of the environment on plant performance requires growing plants under controlled environmental conditions. Plant phenotypes are a product of genotype × environment (G × E), and the Enviratron at Iowa State University is a facility for testing under controlled conditions the effects of the environment on plant growth and development. Crop plants (including maize) can be grown to maturity in the Enviratron, and the performance of plants under different environmental conditions can be monitored 24 h per day, 7 days per week throughout the growth cycle.

Results: The Enviratron is an array of custom-designed plant growth chambers that ...


A Meta-Analysis Of Global Fungal Distribution Reveals Climate-Driven Patterns, Tomáš Větrovský, Petr Kohout, Martin Kopecký, Antonin Machac, Matěj Man, Barbara Doreen Bahnmann, Vendula Brabcová, Jinlyung Choi, Lenka Meszárošová, Zander Rainier Human, Clémentine Lepinay, Salvador Lladó, Rubén López-Mondéjar, Tijana Martinović, Tereza Mašínová, Daniel Morais, Diana Navrátilová, Iñaki Odriozola, Martina Štursová, Karel Švec, Vojtěch Tláskal, Michaela Urbanová, Joe Wan, Lucia Žifčáková, Adina Howe, Joshua Ladau, Kabir Gabriel Peay, David Storch, Jan Wild, Petr Baldrian Nov 2019

A Meta-Analysis Of Global Fungal Distribution Reveals Climate-Driven Patterns, Tomáš Větrovský, Petr Kohout, Martin Kopecký, Antonin Machac, Matěj Man, Barbara Doreen Bahnmann, Vendula Brabcová, Jinlyung Choi, Lenka Meszárošová, Zander Rainier Human, Clémentine Lepinay, Salvador Lladó, Rubén López-Mondéjar, Tijana Martinović, Tereza Mašínová, Daniel Morais, Diana Navrátilová, Iñaki Odriozola, Martina Štursová, Karel Švec, Vojtěch Tláskal, Michaela Urbanová, Joe Wan, Lucia Žifčáková, Adina Howe, Joshua Ladau, Kabir Gabriel Peay, David Storch, Jan Wild, Petr Baldrian

Agricultural and Biosystems Engineering Publications

The evolutionary and environmental factors that shape fungal biogeography are incompletely understood. Here, we assemble a large dataset consisting of previously generated mycobiome data linked to specific geographical locations across the world. We use this dataset to describe the distribution of fungal taxa and to look for correlations with different environmental factors such as climate, soil and vegetation variables. Our meta-study identifies climate as an important driver of different aspects of fungal biogeography, including the global distribution of common fungi as well as the composition and diversity of fungal communities. In our analysis, fungal diversity is concentrated at high latitudes ...


Characterizing The Soil Microbiome And Quantifying Antibiotic Resistance Gene Dynamics In Agricultural Soil Following Swine Cafo Manure Application, Edward Lopatto, Jinlyung Choi, Alfredo Colina, Lanying Ma, Adina Howe, Shannon Hinsa-Leasure Aug 2019

Characterizing The Soil Microbiome And Quantifying Antibiotic Resistance Gene Dynamics In Agricultural Soil Following Swine Cafo Manure Application, Edward Lopatto, Jinlyung Choi, Alfredo Colina, Lanying Ma, Adina Howe, Shannon Hinsa-Leasure

Agricultural and Biosystems Engineering Publications

As agriculture industrializes, concentrated animal feeding operations (CAFOs) are becoming more common. Feces from CAFOs is often used as fertilizer on fields. However, little is known about the effects manure has on the soil microbiome, which is an important aspect of soil health and fertility. In addition, due to the subtherapeutic levels of antibiotics necessary to keep the animals healthy, CAFO manure has elevated levels of antibiotic resistant bacteria. Using 16s rRNA high-throughput sequencing and qPCR, this study sought to determine the impact of swine CAFO manure application on both the soil microbiome and abundance of select antibiotic resistance genes ...


Impact Of Hydraulic Residence Time On Nitrate Removal In Pilot-Scale Woodchip Bioreactors, E. A. Martin, Morgan P. Davis, Thomas B. Moorman, Thomas M. Isenhart, Michelle L. Soupir May 2019

Impact Of Hydraulic Residence Time On Nitrate Removal In Pilot-Scale Woodchip Bioreactors, E. A. Martin, Morgan P. Davis, Thomas B. Moorman, Thomas M. Isenhart, Michelle L. Soupir

Agricultural and Biosystems Engineering Publications

Nitrate (NO3−N) export from row crop agricultural systems with subsurface tile drainage continues to be a major water quality concern. Woodchip bioreactors are an effective edge-of-field practice designed to remove NO3−N from tile drainage. The NO3−N removal rate of woodchip bioreactors can be impacted by several factors, including hydraulic residence time(HRT). This study examined the impact of three HRTs, 2 h, 8 h, and 16 h, on NO3−N removal in a set of nine pilot-scale woodchip bioreactors in Central Iowa. NO3−N concentration reduction from the inlet to the outlet was significantly different for all ...


Effects Of Harvest Time On The Aroma Of White Wines Made From Cold-Hardy Brianna And Frontenac Gris Grapes Using Headspace Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry-Olfactometry, Somchai Rice, Madina Tursumbayeva, Matthew Clark, David Greenlee, Murlidhar Dharmadhikari, Anne Fennell, Jacek A. Koziel Jan 2019

Effects Of Harvest Time On The Aroma Of White Wines Made From Cold-Hardy Brianna And Frontenac Gris Grapes Using Headspace Solid-Phase Microextraction And Gas Chromatography-Mass Spectrometry-Olfactometry, Somchai Rice, Madina Tursumbayeva, Matthew Clark, David Greenlee, Murlidhar Dharmadhikari, Anne Fennell, Jacek A. Koziel

Agricultural and Biosystems Engineering Publications

The Midwest wine industry has shown a marked increase in growers, hectares planted, wineries, and wine production. This growth coincides with the release of cold-hardy cultivars such as Brianna and Frontenac gris, in 2001 and 2003, respectively. These white grape varieties account for one-third of the total area grown in the state of Iowa. It is generally accepted that the wine aroma profile plays a crucial role in developing a local, sustainable brand. However, the identity of Brianna/Frontenac Gris-based wine aromas and their link to the grape berry chemistry at harvest is unknown. This study aims to preliminarily characterize ...


Refsoil+: A Reference Database For Genes And Traits Of Soil Plasmids, Taylor K. Dunivin, Jinlyung Choi, Adina Howe, Ashley Shade Jan 2019

Refsoil+: A Reference Database For Genes And Traits Of Soil Plasmids, Taylor K. Dunivin, Jinlyung Choi, Adina Howe, Ashley Shade

Agricultural and Biosystems Engineering Publications

Plasmids harbor transferable genes that contribute to the functional repertoire of microbial communities, yet their contributions to metagenomes are often overlooked. Environmental plasmids have the potential to spread antibiotic resistance to clinical microbial strains. In soils, high microbiome diversity and high variability in plasmid characteristics present a challenge for studying plasmids. To improve the understanding of soil plasmids, we present RefSoil+, a database containing plasmid sequences from 922 soil microorganisms. Soil plasmids were larger than other described plasmids, which is a trait associated with plasmid mobility. There was a weak relationship between chromosome size and plasmid size and no relationship ...


Seasonal And Intra-Event Nutrient Levels In Farmed Prairie Potholes Of The Des Moines Lobe, Alexander R. Martin, Michelle L. Soupir, Amy L. Kaleita Jan 2019

Seasonal And Intra-Event Nutrient Levels In Farmed Prairie Potholes Of The Des Moines Lobe, Alexander R. Martin, Michelle L. Soupir, Amy L. Kaleita

Agricultural and Biosystems Engineering Publications

The prairie pothole region ranges from central Iowa to the northwest into Montana and south-central Canada, totaling around 700,000 km2. This area contains millions of potholes, or enclosed topographical depressions, which often inundate with rainfall. Many are located in areas that have been converted to agricultural land through installation of artificial drainage. However, even with drainage, potholes pond or remain saturated during and after significant rain events. In this two-year study, surface water depth was collected hourly (typically from after planting through harvest) from eight farmed potholes (drained and under corn-soybean rotation) on the Des Moines Lobe in central ...


Field-Based Robot Phenotyping Of Sorghum Plant Architecture Using Stereo Vision, Yin Bao, Lie Tang, Matthew W. Breitzman, Maria G. Salas-Fernandez, Patrick S. Schnable Oct 2018

Field-Based Robot Phenotyping Of Sorghum Plant Architecture Using Stereo Vision, Yin Bao, Lie Tang, Matthew W. Breitzman, Maria G. Salas-Fernandez, Patrick S. Schnable

Agricultural and Biosystems Engineering Publications

Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study ...


Modelling The Influence Of Crop Density And Weather Conditions On Field Drying Characteristics Of Switchgrass And Maize Stover Using Random Forest, Amit Khanchi, Stuart J. Birrell, Robert B. Mitchell May 2018

Modelling The Influence Of Crop Density And Weather Conditions On Field Drying Characteristics Of Switchgrass And Maize Stover Using Random Forest, Amit Khanchi, Stuart J. Birrell, Robert B. Mitchell

Agricultural and Biosystems Engineering Publications

Field drying trials were conducted using both field baskets as well as grab sampling techniques to study drying behaviour of switchgrass and maize (corn) stover (CS). Environmental conditions such as hourly solar radiation, vapour pressure deficit (VPD), average wind speed, rainfall amount, harvesting method, and field operations such as swath density were used as variables for model development. A powerful classification-based algorithm, which uses a collection of decision trees called random forest (RF) was utilised to predict moisture content (MC) of switchgrass and CS on wet basis. RF predicted the MC of switchgrass and CS with a coefficient of determination ...


Portable Canopy Chamber Measurements Of Evapotranspiration In Corn, Soybean, And Reconstructed Prairie, Chenyi Luo, Zhuangji Wang, Thomas J. Sauer, Matthew J. Helmers, Robert Horton Feb 2018

Portable Canopy Chamber Measurements Of Evapotranspiration In Corn, Soybean, And Reconstructed Prairie, Chenyi Luo, Zhuangji Wang, Thomas J. Sauer, Matthew J. Helmers, Robert Horton

Agricultural and Biosystems Engineering Publications

Evapotranspiration (ET) is a vital component of a field water balance. Canopy chambers are a promising method for determining crop ET because they are portable and applicable at a relatively small plot (m2) scale. Although a variety of canopy chamber designs have been proposed, field tests are still necessary to evaluate chamber performance for measuring crop ET. The objectives of this study are (1) to construct and use an improved canopy chamber to measure ET of three crops [corn (Zea mays, L.), soybean (Glycine max), and reconstructed mixed prairie] and (2) to compare the canopy chamber measurements with flux tower ...


Salmonella And Fecal Indicator Bacteria Survival In Soils Amended With Poultry Manure, Claire E. Hruby, Michelle L. Soupir, Thomas B. Moorman, Carl H. Pederson, Rameshwar S. Kanwar Feb 2018

Salmonella And Fecal Indicator Bacteria Survival In Soils Amended With Poultry Manure, Claire E. Hruby, Michelle L. Soupir, Thomas B. Moorman, Carl H. Pederson, Rameshwar S. Kanwar

Agricultural and Biosystems Engineering Publications

Minimizing the risks associated with manure-borne pathogenic microorganisms requires an understanding of microbial survival under realistic field conditions. The objective of this 3-year study was to assess the fate of Salmonella (SALM) and fecal indicator bacteria (FIB), E. coli (EC) and enterococci (ENT), in glacial till-derived soils, after application of poultry manure (PM) to cornfields under chisel-plowed (CP) or no-till (NT) management. From 2010 to 2012, soil samples were obtained each spring at 0–15- and 15–30-cm depths, to determine whether over-wintering of target bacteria had occurred. Sampling was followed by application of PM at low (PM1) and high ...


Evaluating Row Cover Establishment Systems For Cantaloupe And Summer Squash, H. Mark Hanna, Brian L. Steward, Kurt A. Rosentrater Jan 2018

Evaluating Row Cover Establishment Systems For Cantaloupe And Summer Squash, H. Mark Hanna, Brian L. Steward, Kurt A. Rosentrater

Agricultural and Biosystems Engineering Publications

Use of row covers offer an alternative to pesticide application for management of insect feeding and disease transmission and can be beneficial for extending the growing season. Unfortunately, labor required to establish cover is significant (particularly for single rows) and larger pieces of multi-row cover are subject to fatigue from wind and sun. Development of a mechanized single-row cover system or a durable multi-row cover system advances potential for use of covers. Field tests of a commercial semi-mechanized cover implement were conducted. Successful wire insertion ranged from 74 to 100% and depended on careful adjustment of the implement. Success was ...


A High-Throughput, Field-Based Phenotyping Technology For Tall Biomass Crops, Maria G. Salas Fernandez, Yin Bao, Lie Tang, Patrick Schnable Dec 2017

A High-Throughput, Field-Based Phenotyping Technology For Tall Biomass Crops, Maria G. Salas Fernandez, Yin Bao, Lie Tang, Patrick Schnable

Agricultural and Biosystems Engineering Publications

Recent advances in "omics" technologies have not been accompanied by equally efficient, cost-effective and accurate phenotyping methods required to dissect the genetic architecture of complex traits. Even though high-throughput phenotyping platforms have been developed for controlled environments, field-based aerial and ground technologies have only been designed and deployed for short stature crops. Therefore, we developed and tested Phenobot 1.0, an auto-steered and self-propelled field-based high-throughput phenotyping platform for tall dense canopy crops, such as sorghum (Sorghum bicolor L. Moench). Phenobot 1.0 was equipped with laterally positioned and vertically stacked stereo RGB cameras. Images collected from 307 diverse sorghum ...


A Robotic Platform For Corn Seedling Morphological Traits Characterization, Hang Lu, Lie Tang, Steven A. Whitham, Yu Mei Sep 2017

A Robotic Platform For Corn Seedling Morphological Traits Characterization, Hang Lu, Lie Tang, Steven A. Whitham, Yu Mei

Agricultural and Biosystems Engineering Publications

Crop breeding plays an important role in modern agriculture, improving plant performance, and increasing yield. Identifying the genes that are responsible for beneficial traits greatly facilitates plant breeding efforts for increasing crop production. However, associating genes and their functions with agronomic traits requires researchers to observe, measure, record, and analyze phenotypes of large numbers of plants, a repetitive and error-prone job if performed manually. An automated seedling phenotyping system aimed at replacing manual measurement, reducing sampling time, and increasing the allowable work time is thus highly valuable. Toward this goal, we developed an automated corn seedling phenotyping platform based on ...


The Effect Of Five Biomass Cropping Systems On Soil-Saturated Hydraulic Conductivity Across A Topographic Gradient, Lisa A. Schulte-Moore, Matthew J. Helmers, Randall K. Kolka Sep 2017

The Effect Of Five Biomass Cropping Systems On Soil-Saturated Hydraulic Conductivity Across A Topographic Gradient, Lisa A. Schulte-Moore, Matthew J. Helmers, Randall K. Kolka

Agricultural and Biosystems Engineering Publications

Understanding the environmental impact of bioenergy crops is needed to inform bioenergy policy development. We determined the effects of five biomass cropping systems—continuous maize (Zea mays), soybean (Glycine max)-triticale (Triticosecale ×)/soybean-maize, maize-switchgrass (Panicum virgatum), triticale/sorghum (Sorghum bicolor), and triticale-aspen (Populus alba × P. grandidentata)—on soil-saturated hydraulic conductivity (K S ) across a toposequence in central Iowa, USA. We compared data from the time of cropping system establishment in 2009 to 4 years post-establishment. Both our 2009 and 2013 data confirmed that cropping system impacts on K S vary by landscape position. We found that differences in cropping system ...


Allelic Variation In Outer Membrane Protein A And Its Influence On Attachment Of Escherichia Coli To Corn Stover, Chunyu Liao, Xiao Liang, Fan Yang, Michelle L. Soupir, Adina C. Howe, Michael L. Thompson, Laura R. Jarboe May 2017

Allelic Variation In Outer Membrane Protein A And Its Influence On Attachment Of Escherichia Coli To Corn Stover, Chunyu Liao, Xiao Liang, Fan Yang, Michelle L. Soupir, Adina C. Howe, Michael L. Thompson, Laura R. Jarboe

Agricultural and Biosystems Engineering Publications

Understanding the genetic factors that govern microbe-sediment interactions in aquatic environments is important for water quality management and reduction of waterborne disease outbreaks. Although chemical properties of bacteria have been identified that contribute to initiation of attachment, the outer membrane proteins that contribute to these chemical properties still remain unclear. In this study we explored the attachment of 78 Escherichia coli environmental isolates to corn stover, a representative agricultural residue. Outer membrane proteome analysis led to the observation of amino acid variations, some of which had not been previously described, in outer membrane protein A (OmpA) at 10 distinct locations ...


Influence Of Uv Treatment On The Food Safety Status Of A Model Aquaponic System, Sai Deepikaa Elumalai, Angela M. Shaw, D. Allen Pattillo, Christopher J. Currey, Kurt A. Rosentrater, Kun Xie Jan 2017

Influence Of Uv Treatment On The Food Safety Status Of A Model Aquaponic System, Sai Deepikaa Elumalai, Angela M. Shaw, D. Allen Pattillo, Christopher J. Currey, Kurt A. Rosentrater, Kun Xie

Agricultural and Biosystems Engineering Publications

Few microbial studies in aquaponics, a growing trend in food production, have been conducted to determine food safety status. The aim of this study was to determine the food safety status and the effectiveness of ultraviolet treatment (15 W, luminous flux of 900 lm) as a food safety intervention in reducing the microbial loads of the water system in a model aquaponic unit growing lettuce, basil, and barramundi (Australian Sea Bass). Sweet basil, bibb lettuce, water samples, and fish swabs were collected throughout the 118-day production period, and microbial analysis was conducted in triplicate for the presence of E. coli ...


Soil Ozonation For Nematode Disinfestation As An Alternative To Methyl Bromide And Nematicides, Nahed Msayleb, Rameshwar S. Kanwar, Huaiqing Wu, Johannes Van Leeuwen Jan 2017

Soil Ozonation For Nematode Disinfestation As An Alternative To Methyl Bromide And Nematicides, Nahed Msayleb, Rameshwar S. Kanwar, Huaiqing Wu, Johannes Van Leeuwen

Agricultural and Biosystems Engineering Publications

Phytoparasitic nematodes are important pests that cause severe crop yield losses. In the past, methyl bromide and other proprietary nematicides have been used as management practices, but these practices are unsustainable and lead to atmospheric pollution and ozone layer destruction. Ozonation was studied as an alternative management practice since it is highly effective against microorganisms and degenerates quickly to oxygen. Soil samples that were naturally infested with nematodes were treated with different levels of gaseous ozone at 21 ºC and 5 ºC. Regression analysis results show that a medium level of ozonation (2.1 g O3 kg-1 for 15 min ...


Ozonation Efficacy In The Treatment Of Soil-Borne Phytophthora Sojae In Cultivating Soybeans, Nahed Msayleb, Rameshwar S. Kanwar, Huaiqing Wu, Johannes Van Leeuwen Jan 2017

Ozonation Efficacy In The Treatment Of Soil-Borne Phytophthora Sojae In Cultivating Soybeans, Nahed Msayleb, Rameshwar S. Kanwar, Huaiqing Wu, Johannes Van Leeuwen

Agricultural and Biosystems Engineering Publications

Ozonation was studied for inactivating Phytophthora sojae, a predominant soybean pathogen that causes root and stem rot, and pre-and post-emergence soybean damping-off. Typically, fungicides are used to treat soils to control the damage from P. sojae to soybean production. An environmentally friendly method of ozonation was studied for inactivating P. sojae, a model Phytophthora pathogen that affects a wide range of high-value crops. Assays of artificially inoculated soil samples with P. sojae were treated with different doses of gaseous ozone. This study showed that a dosage of 0.47 g.kg-1 O3 in the soil totally prevented root and stem-rot ...


E. Coli Surface Properties Differ Between Stream Water And Sediment Environments, Xiao Liang, Chunyu Liao, Michael L. Thompson, Michelle L. Soupir, Laura R. Jarboe, Philip M. Dixon Nov 2016

E. Coli Surface Properties Differ Between Stream Water And Sediment Environments, Xiao Liang, Chunyu Liao, Michael L. Thompson, Michelle L. Soupir, Laura R. Jarboe, Philip M. Dixon

Agricultural and Biosystems Engineering Publications

The importance of E. coli as an indicator organism in fresh water has led to numerous studies focusing on cell properties and transport behavior. However, previous studies have been unable to assess if differences in E. coli cell surface properties and genomic variation are associated with different environmental habitats. In this study, we investigated the variation in characteristics of E. coli obtained from stream water and stream bottom sediments. Cell properties were measured for 77 genomically different E. coli strains (44 strains isolated from sediments and 33 strains isolated from water) under common stream conditions in the Upper Midwestern United ...


Nitrogen Fertilizer Use Efficiency Of Pepper As Affected By Irrigation And Fertilization Regime, Vjekoslav Tanaskovik, Ordan Cukaliev, Rameshwar S. Kanwar, Lee K. Heng, Mile Markoski, Velibor Spalevic Jan 2016

Nitrogen Fertilizer Use Efficiency Of Pepper As Affected By Irrigation And Fertilization Regime, Vjekoslav Tanaskovik, Ordan Cukaliev, Rameshwar S. Kanwar, Lee K. Heng, Mile Markoski, Velibor Spalevic

Agricultural and Biosystems Engineering Publications

The pepper producers in the Republic of Macedonia have used drip irrigation systems to increase yield in recent years, but more research is still needed, related to irrigation scheduling and precise requirement of nitrogen fertilizer to maximise pepper yield. Therefore, a two year experiment was conducted in a plastic house to determine the nitrogen fertilizer use efficiency (NFUE) and yield potential of pruned pepper as affected by irrigation and fertilization regime. Four experimental treatments were applied in this study. Three of the treatments were drip fertigated (DF1, DF2, DF3), while the fourth treatment was furrow irrigated with conventional fertilization (ØB ...


Root Responses Of Jerusalem Artichoke Genotypes To Different Water Regimes, Ruttanachira Ruttanaprasert, Sanun Jogloy, Nimitr Vorasoot, Thawan Kesmala, Rameshwar S. Kanwar, Carl C. Holbrook, Aran Patanothai Oct 2015

Root Responses Of Jerusalem Artichoke Genotypes To Different Water Regimes, Ruttanachira Ruttanaprasert, Sanun Jogloy, Nimitr Vorasoot, Thawan Kesmala, Rameshwar S. Kanwar, Carl C. Holbrook, Aran Patanothai

Agricultural and Biosystems Engineering Publications

The objective of this study was to determine effects of drought on selected root growth parameters and develop relationships between root parameters and tuber yield for selected Jerusalem artichoke (JA) genotypes. Three water regimes (Field capacity, 50% available soil water (AW) and 25% AW) and five JA varieties (JA 60, JA 125, JA 5, JA 89 and HEL 65) were planted with factorial treatments in a randomized complete block design with four replications. Data on root dry weight (RDW) and root: shoot ratios (RSR) were measured manually. Root diameter (RD), root length (RL), root surface area (RSA) and root volume ...


What Does It Take To Detect A Change In Soil Carbon Stock? A Regional Comparison Of Minimum Detectable Difference And Experiment Duration In The North Central United States, Magdalena Necpálová, Robert P. Anex Jr., Alexandra N. Kravchenko, Lori J. Abendroth, Stephen J. Del Grosso, Warren A. Dick, Matthew J. Helmers, Daryl E. Herzmann, Joseph G. Lauer, Emerson D. Nafziger, John E. Sawyer, Peter C. Scharf, Jeffrey S. Strock, Maria B. Villamil Nov 2014

What Does It Take To Detect A Change In Soil Carbon Stock? A Regional Comparison Of Minimum Detectable Difference And Experiment Duration In The North Central United States, Magdalena Necpálová, Robert P. Anex Jr., Alexandra N. Kravchenko, Lori J. Abendroth, Stephen J. Del Grosso, Warren A. Dick, Matthew J. Helmers, Daryl E. Herzmann, Joseph G. Lauer, Emerson D. Nafziger, John E. Sawyer, Peter C. Scharf, Jeffrey S. Strock, Maria B. Villamil

Agricultural and Biosystems Engineering Publications

Variability in soil organic carbon (SOC) results from natural and human processes interacting across time and space, and leads to large variation in the minimum difference in SOC that can be detected with a particular experimental design. Here we report a unique comparison of minimum detectable differences (MDDs) in SOC, and the estimated times required to observe those MDDs across the north central United States, calculated for the two most common SOC experiments: (1) a comparison between two treatments, e.g., moldboard plow (MP) and no-tillage (NT), using a randomized complete block design experiment; and (2) a comparison of changes ...


Fumonisins In Conventional And Transgenic, Insect-Resistant Maize Intended For Fuel Ethanol Production: Implications For Fermentation Efficiency And Ddgs Co-Product Quality, Erin L. Bowers, Gary P. Munkvold Sep 2014

Fumonisins In Conventional And Transgenic, Insect-Resistant Maize Intended For Fuel Ethanol Production: Implications For Fermentation Efficiency And Ddgs Co-Product Quality, Erin L. Bowers, Gary P. Munkvold

Agricultural and Biosystems Engineering Publications

Mycotoxins in maize grain intended for ethanol production are enriched in co-product dried distiller’s grains and solubles (DDGS) and may be detrimental to yeast in fermentation. This study was conducted to examine the magnitude of fumonisin enrichment in DDGS and to analyze the impacts of insect injury, Fusarium ear rot severity, and fumonisin contamination on final ethanol yield. Samples of naturally-contaminated grain (0 to 35 mg/kg fumonisins) from field trials conducted in 2008–2011 were fermented and DDGS collected and analyzed for fumonisin content. Ethanol yield (determined gravimetrically) was unaffected by fumonisins in the range occurring in this ...


Nitrogen And Carbon Dynamics In Prairie Vegetation Strips Across Topographical Gradients In Mixed Central Iowa Agroecosystems, Marlín Pérez-Suárez, Michael J. Castellano, Randall K. Kolka, Heidi Asbjornsen, Matthew J. Helmers Apr 2014

Nitrogen And Carbon Dynamics In Prairie Vegetation Strips Across Topographical Gradients In Mixed Central Iowa Agroecosystems, Marlín Pérez-Suárez, Michael J. Castellano, Randall K. Kolka, Heidi Asbjornsen, Matthew J. Helmers

Agricultural and Biosystems Engineering Publications

Reductions of nitrogen (N) export from agricultural lands because of changes in specific N stocks and fluxes by incorporation of small amounts of prairie vegetation strips (PVS) are poorly understood. The primary objective of this study was to evaluate the effect of the presence and topographical position of PVS on soil and plant carbon (C) and N stocks relative to annual crop and native prairie vegetation. The study was implemented within three small adjacent watersheds, treated with one of the following cover types: (1) 100% row-crop agriculture (CROP); (2) 20% prairie vegetation (PVS) distributed along the contour across three topographical ...


Biodegradation Behavior Of Bacterial-Based Polyhydroxyalkanoate (Pha) And Ddgs Composites, Samy A. Madbouly, James A. Schrader, Gowrishankar Srinivasan, Kunwei Liu, Kenneth Mccabe, David A. Grewell, William R. Graves, Michael R. Kessler Jan 2014

Biodegradation Behavior Of Bacterial-Based Polyhydroxyalkanoate (Pha) And Ddgs Composites, Samy A. Madbouly, James A. Schrader, Gowrishankar Srinivasan, Kunwei Liu, Kenneth Mccabe, David A. Grewell, William R. Graves, Michael R. Kessler

Agricultural and Biosystems Engineering Publications

The extensive use of plastics in agriculture has increased the need for development and implementation of polymer materials that can degrade in soils under natural conditions. The biodegradation behavior in soil of polyhydroxyalkanoate (PHA) composites with 10 wt% distiller's dried grains with solubles (DDGS) was characterized and compared to pure PHA over 24 weeks. Injection-molded samples were measured for degradation weight loss every 4 weeks, and the effects of degradation times on morphological, thermomechanical, and viscoelastic properties were evaluated by scanning electron microscopy (SEM), dynamic mechanical analysis (DMA), and small-amplitude oscillatory shear flow experiments. Incorporation of DDGS had a ...


Novel Bio-Based Composites Of Polyhydroxyalkanoate (Pha)/Distillers Dried Grains With Solubles (Ddgs), Hong Lu, Samy A. Madbouly, James A. Schrader, Michael A. Kessler, David A. Grewell, William R. Graves Jan 2014

Novel Bio-Based Composites Of Polyhydroxyalkanoate (Pha)/Distillers Dried Grains With Solubles (Ddgs), Hong Lu, Samy A. Madbouly, James A. Schrader, Michael A. Kessler, David A. Grewell, William R. Graves

Agricultural and Biosystems Engineering Publications

The PHA/DDGS composite is a promising low-cost, bio-based material for use in crop containers for the horticulture industry. This research effort has quantified the effects on mechanical and thermal properties of adding different amounts of DDGS to a PHA matrix. PHA and DDGS were mixed using a twin-screw microcompounder. Fracture surface morphology and thermal and rheological properties were evaluated using scanning electron microscopy (SEM), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and rheometer measurements. The adhesion between PHA and DDGS decreased with an increase in DDGS content from 10% to 30%. Melting temperature and crystalline ...


Nutrient Removal By Prairie Filter Strips In Agricultural Landscapes, Xiaobo Zhou, Matthew J. Helmers, Heidi Asbjornsen, Randall K. Kolka, Mark D. Tomer, Richard M. Cruse Jan 2014

Nutrient Removal By Prairie Filter Strips In Agricultural Landscapes, Xiaobo Zhou, Matthew J. Helmers, Heidi Asbjornsen, Randall K. Kolka, Mark D. Tomer, Richard M. Cruse

Agricultural and Biosystems Engineering Publications

Nitrogen (N) and phosphorus (P) from agricultural landscapes have been identified as primary sources of excess nutrients in aquatic systems. The main objective of this study was to evaluate the effectiveness of prairie filter strips (PFS) in removing nutrients from cropland runoff in 12 small watersheds in central Iowa. Four treatments with PFS of different spatial coverage and distribution (No-PFS, 10% PFS, 10% PFS with strips, and 20% PFS with strips) were arranged in a balanced incomplete block design across four blocks in 2007. A no-tillage two-year corn (Zea mays L.) –soybean (Glycine max [L.] Merr.) rotation was grown in ...


Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart J. Birrell, David A. Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt Jan 2014

Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart J. Birrell, David A. Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt

Agricultural and Biosystems Engineering Publications

Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus ×giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced for ...