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Full-Text Articles in Life Sciences

Canavalia And Dolichos Extracts For Sustainable Pest Biocontrol And Plant Nutrition Improvement In El Salvador, Carlos Martinez Oct 2019

Canavalia And Dolichos 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 ...


Drainage Water Quality Impacts Of Agricultural Management Practices: Effect Of Manure Application Timing And Cover Crops, Brian Dougherty, Carl Pederson, Michelle Soupir, Dan Andersen Jun 2019

Drainage Water Quality Impacts Of Agricultural Management Practices: Effect Of Manure Application Timing And Cover Crops, Brian Dougherty, Carl Pederson, Michelle Soupir, Dan Andersen

Daniel S. Andersen

The primary objective of this study is to evaluate the impact of various cropping and nutrient management systems on drainage water quality and crop yields. Treatment comparisons evaluate the impact of liquid swine manure application timing, nitrification inhibitor with late fall swine manure application, cereal rye cover crop, and gypsum application. These comparisons will be conducted for multiple years and used to develop appropriate manure and nutrient management practices in order to minimize water contamination potential and enhance the use of swine manure as a nutrient resource.


Effects Of Bt Plants On Non-Target Herbivores, Richard L. Hellmich, Jarrad R. Prasifka, Patricia L. Anderson Jun 2019

Effects Of Bt Plants On Non-Target Herbivores, Richard L. Hellmich, Jarrad R. Prasifka, Patricia L. Anderson

Richard L Hellmich

INTRODUCTION

Transgenic (genetically modified) crops producing insecticidal toxins derived from Bacillus thuringiensis (Bt) bacteria have been scrutinised by government agencies, scientists and the public for their potential to negatively impact non-target organisms in or surrounding agricultural habitats. While several crops have been engineered to express one or more Bt toxins, it is such com (= maize) varieties that have had commercial success. Many strains of Bt exist, each producing one or more toxic crystalline (Cry) proteins, but the deleterious effects of each toxin are usually confined to a few related species in a single order of insects. The species to which ...


Soil Quality And Region Influence Performance And Ranking Of Switchgrass Genotypes, M. D. Casler, S. Sosa, A. R. Boe, S. A. Bonos Jun 2019

Soil Quality And Region Influence Performance And Ranking Of Switchgrass Genotypes, M. D. Casler, S. Sosa, A. R. Boe, S. A. Bonos

Arvid Boe

Development of switchgrass (Panicum virgatum L.) as a dedicated bioenergy feedstock requires intensive and extensive breeding programs that include careful and thoughtful consideration of appropriate target populations of environments (TPEs). The purpose of this study was to evaluate region (climate), soil quality, and N fertilization level as potential factors influencing the choice of TPE. A total of 45 switchgrass genotypes were evaluated in uniform field studies at six field sites defined as prime or marginal soils in New Jersey, South Dakota, and Wisconsin. Region and soil quality had strong interactions with genotype, but N fertilization had little impact on genetic ...


Native Grass And Legume Biology And Establishment, Arvid A. Boe, P. J. Johnson Jun 2019

Native Grass And Legume Biology And Establishment, Arvid A. Boe, P. J. Johnson

Arvid Boe

No abstract provided.


Biomass Yield Of Switchgrass Cultivars Under High- Versus Low-Input Conditions, Michael D. Casler, Sergio Sosa, Lindsey Hoffman, Hilary Mayton, Calvin Ernst, Paul R. Adler, Arvid R. Boe, Stacy A. Bonos Jun 2019

Biomass Yield Of Switchgrass Cultivars Under High- Versus Low-Input Conditions, Michael D. Casler, Sergio Sosa, Lindsey Hoffman, Hilary Mayton, Calvin Ernst, Paul R. Adler, Arvid R. Boe, Stacy A. Bonos

Arvid Boe

Switchgrass (Panicum virgatum L.) is undergoing development as a biomass crop to support conversion of cellulosic biomass to energy. To avoid the competition of biomass with food or feed crops, most commercialization proposals suggest that switchgrass should be grown exclusively on marginal lands that are not fit for food or feed production. The objective of this study was to investigate the potential for cultivar x environment interactions that would affect the methods and approaches for breeding and evaluating switchgrass cultivars, including both upland and lowland types, for high-input versus low-input types of environments. Biomass yield was measured on 14 cultivars ...


30 Years Of Progress Toward Increased Biomass Yield Of Switchgrass And Big Bluestem, M. D. Casler, K. P. Vogel, D. K. Lee, R. B. Mitchell, P. R. Adler, R. M. Suic, K. D. Johnson, R. L. Kallenbach, A. R. Boe, R. D. Mathison, K. A. Cassida, D. H. Min, J. Crawford, K. J. Moore Jun 2019

30 Years Of Progress Toward Increased Biomass Yield Of Switchgrass And Big Bluestem, M. D. Casler, K. P. Vogel, D. K. Lee, R. B. Mitchell, P. R. Adler, R. M. Suic, K. D. Johnson, R. L. Kallenbach, A. R. Boe, R. D. Mathison, K. A. Cassida, D. H. Min, J. Crawford, K. J. Moore

Arvid Boe

Breeding to improve biomass production of switchgrass (Panicum virgatum L.) and big bluestem (Andropogon gerardii Vitman) for conversion to bioenergy began in 1992. The purpose of this study was (i) to develop a platform for uniform regional testing of cultivars and experimental populations for these species, and (ii) to estimate the gains made by breeding during 1992 to 2012. A total of 25 switchgrass populations and 16 big bluestem populations were planted in uniform regional trials at 13 locations in 2012 and 2014. The reference region was USDA Hardiness Zones 3 through 6 in the humid temperate United States. Significant ...


Genome-Wide Association Mapping In A Diverse Spring Barley Collection Reveals The Presence Of Qtl Hotspots And Candidate Genes For Root And Shoot Architecture Traits At Seedling Stage, Adel H. Abdel-Ghani, Rajiv Sharma, Celestine Wabila, Sidram Dhanagond, Saed J. Owais, Mahmud A. Duwayri, Christian Klukas, Dijun Chen, Thomas Lubberstedt, Nicolaus Von Wirén, Andreas Graner, Benjamin Kilian, Kerstin Neumann Jun 2019

Genome-Wide Association Mapping In A Diverse Spring Barley Collection Reveals The Presence Of Qtl Hotspots And Candidate Genes For Root And Shoot Architecture Traits At Seedling Stage, Adel H. Abdel-Ghani, Rajiv Sharma, Celestine Wabila, Sidram Dhanagond, Saed J. Owais, Mahmud A. Duwayri, Christian Klukas, Dijun Chen, Thomas Lubberstedt, Nicolaus Von Wirén, Andreas Graner, Benjamin Kilian, Kerstin Neumann

Thomas Lubberstedt

Background: Adaptation to drought-prone environments requires robust root architecture. Genotypes with a more vigorous root system have the potential to better adapt to soils with limited moisture content. However, root architecture is complex at both, phenotypic and genetic level. Customized mapping panels in combination with efficient screenings methods can resolve the underlying genetic factors of root traits.

Results: A mapping panel of 233 spring barley genotypes was evaluated for root and shoot architecture traits under non-stress and osmotic stress. A genome-wide association study elucidated 65 involved genomic regions. Among them were 34 root-specific loci, eleven hotspots with associations to up ...


Using Drones For Precision Agriculture, Jiyul Chang, Madhav P. Nepal May 2019

Using Drones For Precision Agriculture, Jiyul Chang, Madhav P. Nepal

Madhav Nepal

In this teaching module, students will learn what Precision Agriculture is and how to apply drone into Precision Agriculture practices. To use data (images) taken by drone, students will learn the basic theory of Remote Sensing. Using images, students learn how to make NDVI (Normalized Difference Vegetation Index) maps and how to apply drone (remote sensing technique) in agriculture.


Pea Growth, Yield, And Quality In Different Crop Rotations And Cultural Practices, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, Jalal D. Jabro, William B. Stevens May 2019

Pea Growth, Yield, And Quality In Different Crop Rotations And Cultural Practices, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, Jalal D. Jabro, William B. Stevens

Andrew W. Lenssen

Dryland pea (Pisum sativum L.) is an important pulse crop that can replace fallow or be added to existing crop rotations to sustain crop yields in arid and semiarid regions. Yet, we lack management practices to enhance yield and quality of dryland pea. This study evaluated the effect of crop rotation and cultural practices on dryland pea growth, yield, and quality from 2006 to 2011 in the northern Great Plains, USA. Stacked rotations were durum (Triticum turgidum L.)–durum–canola (Brassica napus L.)–pea (DDCP) and durum–durum–flax (Linum usitatissimum L.)–pea (DDFP), and alternate-year rotations were durum–canola ...


Historical Nitrogen Fertilizer Use In Agricultural Ecosystems Of The Contiguous United States During 1850–2015: Application Rate, Timing, And Fertilizer Types, Peiyu Cao, Chaoqun (Crystal) Lu, Zhen Yu May 2019

Historical Nitrogen Fertilizer Use In Agricultural Ecosystems Of The Contiguous United States During 1850–2015: Application Rate, Timing, And Fertilizer Types, Peiyu Cao, Chaoqun (Crystal) Lu, Zhen Yu

Chaoqun (Crystal) Lu

A tremendous amount of anthropogenic nitrogen (N) fertilizer has been applied to agricultural lands to promote crop production in the US since the 1850s. However, inappropriate N management practices have caused numerous ecological and environmental problems which are difficult to quantify due to the paucity of spatially explicit time-series fertilizer use maps. Understanding and assessing N fertilizer management history could provide important implications for enhancing N use efficiency and reducing N loss. In this study, we therefore developed long-term gridded maps to depict crop-specific N fertilizer use rates, application timing, and the fractions of ammonium N (NH+ 4 -N) and ...


Global Manure Nitrogen Production And Application In Cropland During 1860–2014: A 5 Arcmin Gridded Global Dataset For Earth System Modeling, Bowen Zhang, Hanqin Tian, Chaoqun (Crystal) Lu, Shree R.S. Dangal, Jia Yang, Shufen Pan May 2019

Global Manure Nitrogen Production And Application In Cropland During 1860–2014: A 5 Arcmin Gridded Global Dataset For Earth System Modeling, Bowen Zhang, Hanqin Tian, Chaoqun (Crystal) Lu, Shree R.S. Dangal, Jia Yang, Shufen Pan

Chaoqun (Crystal) Lu

Given the important role of nitrogen input from livestock systems in terrestrial nutrient cycles and the atmospheric chemical composition, it is vital to have a robust estimation of the magnitude and spatiotemporal variation in manure nitrogen production and its application to cropland across the globe. In this study, we used the dataset from the Global Livestock Impact Mapping System (GLIMS) in conjunction with country-specific annual livestock populations to reconstruct the manure nitrogen production during 1860–2014. The estimated manure nitrogen production increased from 21.4TgNyr−1 in 1860 to 131.0TgNyr−1 in 2014 with a significant annual increasing trend ...


Nutritional Composition Of Grain Legume Leaves And The Impact Of Leaf Removal On Yield, Rosemary Bulyaba, Andrew W. Lenssen May 2019

Nutritional Composition Of Grain Legume Leaves And The Impact Of Leaf Removal On Yield, Rosemary Bulyaba, Andrew W. Lenssen

Andrew W. Lenssen

Grain legumes can thrive in adverse environments, making them a climate-smart technology for hunger mitigation. Although several countries rely immensely on grain legumes to meet daily protein intake requirements per capita, the potentiality of leaf utilization for protein and other nutrients has not been widely considered; additionally, insufficient information is available on leaf removal effects on yield and leaf nutritional composition of grain legumes. A 2-yr experiment was conducted in central Iowa, USA, to determine the effects of leaf removal rates on nutritive value of removed leaf tissue and subsequent grain yield of cowpea [Vigna unguiculata (L.) Walp.], lablab [Lablab ...


Science Communication In Agriculture: The Role Of The Trusted Adviser, Lee Galen Briese May 2019

Science Communication In Agriculture: The Role Of The Trusted Adviser, Lee Galen Briese

Doctoral Documents from Doctor of Plant Health Program

Agronomy is not simply the selling of agricultural products to farmers, nor is it the process of solving singular production problems. Agronomy is defined as the integrated, holistic perspective of agriculture (ASA, 2019) and “agronomists are specialists in crop and soil sciences, as well as ecology” (ASA, 2019). While scientific investigation and discovery are essential to understanding systems function, the tangible benefits from our knowledge stems from the application to solve problems. Clear communication is vital to successfully help stakeholders understand the importance of the science and help scientists understand the challenges stakeholders face. However, to successfully put science into ...


Dna Barcoding Of Pratylenchus From Agroecosystems In The Northern Great Plains Of North America, Mehmet Ozbayrak May 2019

Dna Barcoding Of Pratylenchus From Agroecosystems In The Northern Great Plains Of North America, Mehmet Ozbayrak

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Pratylenchus species are among the most common plant parasitic nematodes in the Great Plains Region. The objectives of this study were to barcode Pratylenchus specimens for species identification in the Great Plains region using mitochondrial CO1 DNA barcode. In order to (1) determine species boundaries, (2) assess the host associations of barcoded Pratylenchus, (3) to determine the distribution patterns across the Great Plains Region and, (4) to evaluate the species status of P. scribneri and P. hexincisus by a multivariate morphological analysis of haplotype groups identified by DNA barcoding. Soil samples, primarily associated with eight major crops, were collected from ...


Use Of Annual Forage Mixtures In Crop/Livestock Production Systems In Nebraska, Nathan Paul Pflueger May 2019

Use Of Annual Forage Mixtures In Crop/Livestock Production Systems In Nebraska, Nathan Paul Pflueger

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Success of integrating annual forages into crop and livestock systems throughout Nebraska may be variable depending on field location, field/forage crop management, and precipitation. There are many different warm- and cool-season annual forage species available for integrating crop and livestock systems at different times of the year. Mixtures of cereal species, such as oats (Avena sativa)) and spring peas (Pisum sativum)), are often used to optimize forage quantity and forage quality. Our two-year, three location study across Nebraska’s precipitation gradient suggested that forage quantity and quality may vary by location due to different precipitation amounts received during the ...


Integrated Management Of Phytophthora Stem And Root Rot Of Soybean And The Effect Of Soil-Applied Herbicides On Seedling Disease Incidence, Vinicius Castelli Garnica May 2019

Integrated Management Of Phytophthora Stem And Root Rot Of Soybean And The Effect Of Soil-Applied Herbicides On Seedling Disease Incidence, Vinicius Castelli Garnica

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Soybean seedling diseases and Phytophthora stem and root rot (PSRR; caused by Phytophthora sojae) are two of the most economically important diseases in North Central U.S. Remarkable differences in disease incidence occur each year, which demonstrate that abiotic and biotic factors must interact for disease onset and development. During 2017 and 2018, field studies were conducted to (i) address the efficacy of seed treatment and genetic resistance for PSRR management on soybean population, canopy coverage (CC), and yield, and (ii) investigate potential interactions between pre-emergence (PRE) herbicides and the incidence of seedling diseases in alluvial soils in Nebraska.

Despite ...


Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson May 2019

Effect Of Soil-Applied Protoporphyrinogen Oxidase Inhibitor Herbicides On Soybean Seedling Disease, Nicholas J. Arneson

Theses, Dissertations, and Student Research in Agronomy and Horticulture

Seedling disease is one the most economically important diseases of soybean in the United States. It is commonly caused by Fusarium spp., Rhizoctonia solani, Pythium spp., and Phytophthora sojae, alone, or together as a disease complex. Fungicide seed treatments continue to provide the most consistent management of seedling diseases. Soil-applied protoporphyrinogen oxidase (PPO) inhibitor herbicides are used preemergence in soybean production to manage several broadleaf weeds. Applications of PPO-inhibitors can result in phytotoxic injury to soybean when environmental conditions are not favorable for soybean growth. These environmental conditions can favor seedling disease development as well. In this thesis, two studies ...


Establishment Of Perennial Legumes With An Annual Warm-Season Grass As A Companion Crop, Martina N. La Vallie May 2019

Establishment Of Perennial Legumes With An Annual Warm-Season Grass As A Companion Crop, Martina N. La Vallie

Theses, Dissertations, and Student Research in Agronomy and Horticulture

The yields of perennial forage legumes are often hindered during the establishment year due to slow germination rates and weed competition. This study was conducted to determine if sorghum-sudangrass (Sorghum bicolor x S. bicolor var. sudanese) is a compatible annual companion crop for increased forage production, weed suppression, and legume establishment. In 2016, sorghum-sudangrass was paired with alfalfa (Medicago sativa L. ‘Ranger’), birdsfoot trefoil (Lotus corniculatus L.), Illinois bundleflower [Desmanthus illinoensis (Michx.) MacMill. ex B.L. Rob. & Fernald], purple prairie clover (Dalea purpurea Vent.), red clover (Trifolium pratense L.), and roundhead lespedeza (Lespedeza capitata Michx.). We studied effects of a sorghum-sudangrass companion crop with a varying number of harvests (three vs. four harvests) collected per plot throughout the summer and compared yields to the yield of a weeded legume treatment, and a non-weeded legume treatment. In 2017, we studied effects of the application of four seeding rates for sorghum-sudangrass at 5 pure live seed per m2 (PLS/m2), 10 PLS/m2, 20 PLS/m2, and 40 PLS/m2 paired with only the alfalfa perennial legume and compared yields to the yield of an oat-alfalfa control treatment, a weeded alfalfa treatment, and a non-weeded alfalfa treatment. Total dry matter yields along with the yield of each legume, weeds, sorghum-sudangrass, and oats (second year only) were collected for each treatment. In both years, we found the addition of sorghum-sudangrass increased overall dry matter yield and significantly decreased weed abundance. The increase in total dry matter yield came at a cost to the legume yield; as treatments planted with sorghum-sudangrass or oats had lower legume/alfalfa yields than weeded legume/alfalfa treatments. These results suggest that sorghum-sudangrass is ...


Reporting Charcoal Rot In Chia And Developing A Susceptibility Assay, Reis M. Misaka, Hagop S. Atamian Dr., Julien Besnard Dr. May 2019

Reporting Charcoal Rot In Chia And Developing A Susceptibility Assay, Reis M. Misaka, Hagop S. Atamian Dr., Julien Besnard Dr.

Student Scholar Symposium Abstracts and Posters

Chia (Salvia Hispanica) cross breeds were planted in the summer of 2018 with the intent of selective breeding for agricultural benefit. Preexisting pathogens in the soil caused 40-50% fatality of adult plants. This was surprising due to the precursory knowledge that chia has antibiotic and antifungal oils (Elshafie et. al. 2018); chia was only recently documented to be susceptible to Fusarium wilt (Fusarium oxysporum). The primary pathogen responsible was identified as Macrophomina phaseolina (aka charcoal rot); a widespread soilborne pathogen which has multiple commercial hosts (Su et. al. 2001).

M. phaesolina on wheat seed vector where used as inoculums (Brandari ...


Evaluation Of Drought Tolerance In Arkansas Cowpea Lines At Seedling Stage, Qirui Cui May 2019

Evaluation Of Drought Tolerance In Arkansas Cowpea Lines At Seedling Stage, Qirui Cui

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Cowpea [Vigna unguiculate (L.) Walp.] is not only a healthy, nutritious and versatile leguminous crop, it also has a relatively high adaptation to drought. Researches have shown that cowpea lines have a high tolerance to drought, and many of them can survive over 40 days under very hot and dry conditions. The cowpea (Southern pea) breeding program at the University of Arkansas (UA) has been active for over 50 years and has produced more than 1,000 advanced breeding lines. And the purpose of this study is to evaluate the drought-tolerant ability in Arkansas cowpea lines and use the drought ...


Determination Of Optimum Harvest Date For Winter Malting Quality Barley In Northwest Arkansas, Paul Wolf May 2019

Determination Of Optimum Harvest Date For Winter Malting Quality Barley In Northwest Arkansas, Paul Wolf

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Due to the strict quality requirements, only 10 percent of worldwide barley is used for malting, though malting quality barley comes with a price increase of up to 50 percent or higher. With the craft brewery industry growing in Northwest Arkansas there is a growing demand for locally sourced malt quality barley. However, data is lacking regarding production practices for barley in Arkansas. The optimum harvest date for malting quality barley is at physiological maturity. This is because many of the malting traits (such as germination energy) decline as harvest is delayed, which will make it difficult to meet the ...


Untangling The Economic And Social Impediments To Producer Adoption Of Organic Wheat, Donya L. Ralph-Quarnstrom May 2019

Untangling The Economic And Social Impediments To Producer Adoption Of Organic Wheat, Donya L. Ralph-Quarnstrom

All Graduate Theses and Dissertations

Consumer demand for organic products has shown double-digit growth in recent years encouraging the development of a wider range of goods (Greene, 2017). Americans with an annual household income under $30,000 actively purchase organic foods at nearly the same rate as households with over $75,000 in annual incomes, 42% versus 49% (Greene et al., 2017). Previous research observed the adoption of organic farming practices on a combination of different grains, fruits and vegetables, meat, and dairy products from across the globe. However, this is the first study to examine the adoption of organic wheat in the Western U ...


Neonicotinoids In U.S. Maize: Insecticide Substitution Effects And Environmental Risk, Edward D. Perry, Giancarlo Moschini May 2019

Neonicotinoids In U.S. Maize: Insecticide Substitution Effects And Environmental Risk, Edward D. Perry, Giancarlo Moschini

CARD Working Papers

This study exploits a novel dataset containing more than 89,000 farm-level surveys over a 17-year period to investigate how neonicotinoid seed treatments in maize, now ubiquitous, have affected the use of other insecticides. Neonicotinoid insecticides are the most used class of insecticides in the world, but they are controversial because of their high toxicity to honeybees. In the United States, maize production accounts for the majority of neonicotinoid use, mostly as seed treatments. We find that neonicotinoids substituted for other major insecticides: plots planted with neonicotinoid- treated seeds were 52% and 47% less likely to be treated with a ...


Implications Of Rice Cultivar Selection To Optimize Returns From Crop Insurance, David Ethan Branscum May 2019

Implications Of Rice Cultivar Selection To Optimize Returns From Crop Insurance, David Ethan Branscum

Theses and Dissertations

Rice production differs from most other field crops by distinct differences in yields across cultivars and rice producers being paid for yield after post-harvest milling. Using eleven years (2003-2013) of Arkansas harvest data from performance trials in six different locations, hybrids have 19% higher paddy yields and head rice yield rate 1.7% lower than conventional cultivars. Given the 2014 Farm Bill’s emphasis on crop insurance as a risk management tool for producers, these variations in yield among cultivars have significant implications for rice producers. Comparing national level, crop insurance data on corn, soybeans and rice indicates rice producers ...


Evaluation Of Crop Tolerance And Weed Control In Corn And Grain Sorghum With Atrazine Replacements, Jacob Thomas Richburg May 2019

Evaluation Of Crop Tolerance And Weed Control In Corn And Grain Sorghum With Atrazine Replacements, Jacob Thomas Richburg

Theses and Dissertations

Atrazine is a foundational herbicide for weed control in both corn (Zea mays L.) and grain sorghum [Sorghum bicolor (L.) Moench] production. However, studies have shown that while atrazine may be an effective herbicide for preemergence and postemergence control of weeds, it also has risks. The low Koc of atrazine as well as its extensive use over the past 50 years have led it to become the most common groundwater contaminant near agricultural soils. Given these findings, atrazine has faced severe scrutiny while under consideration for reregistration. In the event that atrazine is not reregistered, corn and grain sorghum producers ...


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 ...


Susceptibility To Bt Proteins Is Not Required For Agrotis Ipsilon Aversion To Bt Maize, Rachel Renee Binning, Joel R. Coats, Xiaoxiao Kong, Richard L. Hellmich Ii Apr 2019

Susceptibility To Bt Proteins Is Not Required For Agrotis Ipsilon Aversion To Bt Maize, Rachel Renee Binning, Joel R. Coats, Xiaoxiao Kong, Richard L. Hellmich Ii

Richard L Hellmich

Although Bacillus thuringiensis (Bt) maize has been widely adopted in diverse regions around the world, relatively little is known about the susceptibility and behavioral response of certain insect pests to Bt maize in countries where this maize is not currently cultivated. These are important factors to consider as management plans are developed. These factors were investigated for Agrotis ipsilon, a global pest of maize, with Cry1F and Cry34Ab1/Cry35Ab1 maize. Agrotis ipsilon demonstrated an initial, post-ingestive aversive response to Cry1F maize. Development and mortality were also affected – survival on Cry1F maize tissue was 40% and weight gain of survivors of ...


Growth Analysis Of Humulus Lupulus (Hops) Varieties In Montana, Taylor Tyson Apr 2019

Growth Analysis Of Humulus Lupulus (Hops) Varieties In Montana, Taylor Tyson

Carroll College Student Undergraduate Research Festival

Montana currently has a booming brewing industry yet there is a state-wide lack in the production of hops, a critical ingredient in the brewing process. Hops (Humulus lupulus) are a perennial vine that can grow up to 7.5 meters tall and produce cones (female flower structures) which are used to flavor and preserve beer. Our research analyzed the growth of nine different hops varieties grown in the Helena Valley to evaluate the survival, growth, and yield compared to other regions. For our research, four hop varieties were planted in the summer of 2017 and five additional varieties were planted ...


A Cost-Effective And Customizable Automated Irrigation System For Precise High-Throughput Phenotyping In Drought Stress Studies, Diego Ortiz, Alexander G. Litvin, Maria G. Salas Fernandez Apr 2019

A Cost-Effective And Customizable Automated Irrigation System For Precise High-Throughput Phenotyping In Drought Stress Studies, Diego Ortiz, Alexander G. Litvin, Maria G. Salas Fernandez

Maria Salas-Fernandez

The development of high-yielding crops with drought tolerance is necessary to increase food, feed, fiber and fuel production. Methods that create similar environmental conditions for a large number of genotypes are essential to investigate plant responses to drought in gene discovery studies. Modern facilities that control water availability for each plant remain cost-prohibited to some sections of the research community. We present an alternative cost-effective automated irrigation system scalable for a high-throughput and controlled dry-down treatment of plants. This system was tested in sorghum using two experiments. First, four genotypes were subjected to ten days of dry-down to achieve three ...