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Computer Vision And Machine Learning Enabled Soybean Root Phenotyping Pipeline, Kevin G. Falk, Talukder Z. Jubery, Seyed V. Mirnezami, Kyle A. Parmley, Soumik Sarkar, Arti Singh, Baskar Ganapathysubramanian, Asheesh K. Singh Jan 2020

Computer Vision And Machine Learning Enabled Soybean Root Phenotyping Pipeline, Kevin G. Falk, Talukder Z. Jubery, Seyed V. Mirnezami, Kyle A. Parmley, Soumik Sarkar, Arti Singh, Baskar Ganapathysubramanian, Asheesh K. Singh

Mechanical Engineering Publications

Background Root system architecture (RSA) traits are of interest for breeding selection; however, measurement of these traits is difficult, resource intensive, and results in large variability. The advent of computer vision and machine learning (ML) enabled trait extraction and measurement has renewed interest in utilizing RSA traits for genetic enhancement to develop more robust and resilient crop cultivars. We developed a mobile, low-cost, and high-resolution root phenotyping system composed of an imaging platform with computer vision and ML based segmentation approach to establish a seamless end-to-end pipeline - from obtaining large quantities of root samples through image based trait processing and ...


Deconstructing The Genetic Architecture Of Iron Deficiency Chlorosis In Soybean Using Genome-Wide Approaches, Teshale Assefa, Jiaoping Zhang, R. V. Chowda-Reddy, Adrienne N. Moran Lauter, Arti Singh, Jamie A. O'Rourke, Michelle A. Graham, Asheesh K. Singh Jan 2020

Deconstructing The Genetic Architecture Of Iron Deficiency Chlorosis In Soybean Using Genome-Wide Approaches, Teshale Assefa, Jiaoping Zhang, R. V. Chowda-Reddy, Adrienne N. Moran Lauter, Arti Singh, Jamie A. O'Rourke, Michelle A. Graham, Asheesh K. Singh

Agronomy Publications

Background: Iron (Fe) is an essential micronutrient for plant growth and development. Iron deficiency chlorosis (IDC), caused by calcareous soils or high soil pH, can limit iron availability, negatively affecting soybean (Glycine max) yield. This study leverages genome-wide association study (GWAS) and a genome-wide epistatic study (GWES) with previous gene expression studies to identify regions of the soybean genome important in iron deficiency tolerance.

Results: A GWAS and a GWES were performed using 460 diverse soybean PI lines from 27 countries, in field and hydroponic iron stress conditions, using more than 36,000 single nucleotide polymorphism (SNP) markers. Combining this ...


Herbicide Site Of Actions And Potential Damage To Zea Mays And Glycine Max., Justin Friedrich Jan 2020

Herbicide Site Of Actions And Potential Damage To Zea Mays And Glycine Max., Justin Friedrich

Creative Components

With the development of 2,4-D in the 1940s, farmers were able to selectively kill broadleaves in corn (Zea mays). 2,4-D was an effective and powerful tool that allowed farmers to reduce the time spent cultivating cornfields. The development of herbicides allowed farms to increase in size due to the reduction in the time spent interrow-cultivating. Monsanto’s introduction of glyphosate-resistant (Roundup Ready) soybean (Glycine max) in 1996 continued the expansion of farm size. Glyphosate-resistant crops allowed farmers to adopt a “spray and forget” weed management program that was widely adopted. The simplified weed management programs were successful until ...


Plant Disease Identification Using Explainable 3d Deep Learning On Hyperspectral Images, Koushik Nagasubramanian, Sarah Jones, Asheesh K. Singh, Soumik Sarkar, Arti Singh, Baskar Ganapathysubramanian Aug 2019

Plant Disease Identification Using Explainable 3d Deep Learning On Hyperspectral Images, Koushik Nagasubramanian, Sarah Jones, Asheesh K. Singh, Soumik Sarkar, Arti Singh, Baskar Ganapathysubramanian

Mechanical Engineering Publications

Background

Hyperspectral imaging is emerging as a promising approach for plant disease identification. The large and possibly redundant information contained in hyperspectral data cubes makes deep learning based identification of plant diseases a natural fit. Here, we deploy a novel 3D deep convolutional neural network (DCNN) that directly assimilates the hyperspectral data. Furthermore, we interrogate the learnt model to produce physiologically meaningful explanations. We focus on an economically important disease, charcoal rot, which is a soil borne fungal disease that affects the yield of soybean crops worldwide.

Results

Based on hyperspectral imaging of inoculated and mock-inoculated stem images, our 3D ...


A Comparison Of March And April Soybean Planting Dates In South-Central Illinois, Nicholas Patrick Marley Jan 2019

A Comparison Of March And April Soybean Planting Dates In South-Central Illinois, Nicholas Patrick Marley

Creative Components

One of the biggest issues with ultra-early planting of soybean [Glycine max (L.) Merr.] is the lack of research that has been conducted. This study is designed to increase the knowledge base of soybean planting dates by looking at ultra-early (March) versus early (April) planted soybean in south-central Illinois. Field research was conducted in two fields, near Morrisonville, IL over the 2017 and 2018 growing season. In 2017, the March planted soybean required 19 days to gain 121 GDD for emergence to start. Compared to the April planting date where emergence was in 7 days with 123 GDD accumulation. In ...


Genetic Control And Geo-Climate Adaptation Of Pod Dehiscence Provide Novel Insights Into The Soybean Domestication And Expansion, Jiaoping Zhang, Asheesh K. Singh Aug 2018

Genetic Control And Geo-Climate Adaptation Of Pod Dehiscence Provide Novel Insights Into The Soybean Domestication And Expansion, Jiaoping Zhang, Asheesh K. Singh

Agronomy Publications

Loss of pod dehiscence is a key step during soybean [Glycine max (L.) Merr.] domestication. Genome-wide association analysis for soybean shattering identified loci harboring Pdh1, NST1A and SHAT1-5. Pairwise epistatic interactions were observed, and the dehiscent Pdh1 overcomes the resistance conferred by NST1A or SHAT1-5 locus, indicating that Pdh1 predominates pod dehiscence expression. Further candidate gene association analysis identified a nonsense mutation in NST1A associated with pod dehiscence. Allele composition and population differential analyses unraveled that Pdh1 and NST1A, but not SHAT1-5, underwent domestication and modern breeding selections. Geographic analysis showed that in Northeast China (NEC), indehiscence at both Pdh1 ...


A Solution For Sampling Position Errors In Maize And Soybean Root Mass And Length Estimates, Raziel A. Ordonez, Michael J. Castellano, Jerry L. Hatfield, Mark A. Licht, Emily E. Wright, Sotirios V. Archontoulis May 2018

A Solution For Sampling Position Errors In Maize And Soybean Root Mass And Length Estimates, Raziel A. Ordonez, Michael J. Castellano, Jerry L. Hatfield, Mark A. Licht, Emily E. Wright, Sotirios V. Archontoulis

Agronomy Publications

Root mass and length attributes are difficult to obtain in the field and currently there is uniformity among literature studies in estimating the effect of sampling position error. With the objectives of 1) quantifying the sampling position error in calculating weighted average root values per unit area and 2) developing an algorithm to minimize root position sampling error so that existing data in the literature can be used in future studies, we collected and analyzed root mass and length data across four sampling positions (0, 12, 24 and 36 cm distance from the plant row; row-to-row spacing 76 cm) from ...


Using Genomic And Gene Expression Methods To Understand The Phenotypic Response Of Soybean To Sudden Death Syndrome Caused By Fusarium Virguliforme, Alexander Stephen Luckew Jan 2018

Using Genomic And Gene Expression Methods To Understand The Phenotypic Response Of Soybean To Sudden Death Syndrome Caused By Fusarium Virguliforme, Alexander Stephen Luckew

Graduate Theses and Dissertations

Soybean sudden death syndrome (SDS) is one of the most important soybean diseases in the Midwestern United States, leading to average losses of $396 million per year from 1996 to 2015. The causal agent of SDS, soilborne fungus Fusarium virguliforme (Fv), causes root rot symptoms and releases phytotoxins taken up by the plant to produce chlorosis and necrosis in the leaves. The main management practice used to reduce the impact of SDS is planting resistant soybean cultivars. Resistance to SDS is known to be quantitative with 88 known quantitative trait loci (QTL) based on Soybase.org. Many of these QTL ...


Winter Cereal Rye And Selected Brassica Cover Crops For Forage Prior To Soybeans, Timothy James Sklenar Jan 2018

Winter Cereal Rye And Selected Brassica Cover Crops For Forage Prior To Soybeans, Timothy James Sklenar

Graduate Theses and Dissertations

Despite myriad benefits to incorporating winter cover crops into conventionally managed row crop systems farmer adoption remains low in Iowa. Commonly cited apprehensions include the costs associated with managing cover crops without any short term economic benefits and the complexities associated with management of cover crops. The management of cover crops as a forage could potentially help address both of these issues while at the same time enhancing the environmental sustainability of conventionally managed systems. The work provided in this thesis is an attempt to evaluate the potential for four selected species to be managed as dual-purpose winter cover crops ...


Management Of Insecticide-Resistant Soybean Aphids In The Upper Midwest Of The United States, Robert L. Koch, Erin W. Hodgson, Janet J. Knodel, Adam J. Varenhorst, Bruce D. Potter Jan 2018

Management Of Insecticide-Resistant Soybean Aphids In The Upper Midwest Of The United States, Robert L. Koch, Erin W. Hodgson, Janet J. Knodel, Adam J. Varenhorst, Bruce D. Potter

Entomology Publications

Since the first observation of soybean aphid, Aphis glycines Matsumura (Hemiptera: Aphididae), in North America in 2000, it has become the most economically damaging insect of soybean in the Upper Midwest of the United States. For the last 17 yr, soybean aphid management has relied almost entirely on the use of foliar-applied broad-spectrum insecticides. However, in 2015 in Minnesota, failures of foliar-applied pyrethroid insecticides were reported and pyrethroid resistance was confirmed with laboratory bioassays using lambda-cyhalothrin and bifenthrin. In 2016 and 2017, further reports of failures of pyrethroid insecticides and/or laboratory confirmation of resistance occurred in Iowa, North Dakota ...


Evaluation Of Soybean Grain Yield As Influenced By Soybean Seeding Rate And Fomesafen Herbicide, Paul Parcher Jan 2018

Evaluation Of Soybean Grain Yield As Influenced By Soybean Seeding Rate And Fomesafen Herbicide, Paul Parcher

Creative Components

Glyphosate (N-(phosphonomethyl)glycine) herbicide has been extensively used on several herbicide tolerant crops in the United States since the introduction of the first commercially available genetically modified glyphosate-tolerant soybean [Glycine max (L.) Merr.] seed in 1996. The launch of commercially available glyphosate-tolerant corn (Zea mays L.) seed in 1998 provided farmers in Iowa and other states, where corn and soybean are primarily grown, the ability to apply glyphosate to every acre of these crops annually.


Evolution Of Soybean Weed Management In The United States, Aaron Rowe Jan 2018

Evolution Of Soybean Weed Management In The United States, Aaron Rowe

Creative Components

Weeds have been an unwanted nuisance since the beginning of agriculture. The processes and technologies utilized to manage this yield limiting problem have evolved over time. Soybean [Glycine max (L.) Merr.] production in the United States has experienced all of the major agriculture revolutions. This has included horse-drawn field implements, tractor power implementation, chemical era, and the most recent era of biotechnology. There has been a continuous gain in efficiencies with the discovery and introduction of new technologies to manage weeds in soybeans. A period of rapid discovery and introduction of new and novel herbicide sites of action (SOA) with ...


Assessing Causes Of Yield Gaps In Agricultural Areas With Diversity In Climate And Soils, Juan I. Rattalino Edreira, Spyridon Mourtzinis, Shawn P. Conley, Adam C. Roth, Ignacio A. Ciampitti, Mark A. Licht, Hans Kandel, Peter M. Kyveryga, Laura E. Lindsey, Daren S. Mueller, Seth L. Naeve, Emerson Nafziger, James E. Specht, Jordan Stanley, Michael J. Staton, Patricio Grassini Dec 2017

Assessing Causes Of Yield Gaps In Agricultural Areas With Diversity In Climate And Soils, Juan I. Rattalino Edreira, Spyridon Mourtzinis, Shawn P. Conley, Adam C. Roth, Ignacio A. Ciampitti, Mark A. Licht, Hans Kandel, Peter M. Kyveryga, Laura E. Lindsey, Daren S. Mueller, Seth L. Naeve, Emerson Nafziger, James E. Specht, Jordan Stanley, Michael J. Staton, Patricio Grassini

Agronomy Publications

Identification of causes of gaps between yield potential and producer yields has been restricted to small geographic areas. In the present study, we developed a novel approach for identifying causes of yield gaps over large agricultural areas with diversity in climate and soils. This approach was applied to quantify and explain yield gaps in rainfed and irrigated soybean in the North-Central USA (NC USA) region, which accounts for about one third of soybean global production. Survey data on yield and management were collected from 3568 producer fields over two crop seasons and grouped into 10 technology extrapolation domains (TEDs) according ...


Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges, Mark A. Chamberlin, Marc C. Albertsen, Harry T. Horner Oct 2017

Microscopic Characterization Of A Transposon-Induced Male-Sterile, Female-Sterile Mutant In Glycine Max L., Katherine A. Thilges, Mark A. Chamberlin, Marc C. Albertsen, Harry T. Horner

Genetics, Development and Cell Biology Publications

Premise of research. A male-sterile, female-sterile mutant was discovered in a w4-m mutable line of Glycine max L. The mechanism of its sterility was not well understood. Therefore, different cytological and microscopic techniques were undertaken to better understand the process of mutant phenotype development. Molecular research indicated that mer3 was responsible for the sterility.

Methodology. Macro images were collected of whole plants, flowers, anthers, pods, and ovules. Chromosome spreads from anthers at various meiotic stages were examined. Confocal scanning laser microscopy using optical sectioning was utilized on whole anthers and ovules at various developmental stages. Whole mature anthers and ...


Genetic Architecture Of Charcoal Rot (Macrophomina Phaseolina) Resistance In Soybean Revealed Using A Diverse Panel, Sara M. Coser, R. V. Chowda Reddy, Jiaoping Zhang, Daren S. Mueller, Alemu Mengistu, Kiersten A. Wise, Tom W. Allen, Arti Singh, Asheesh K. Singh Sep 2017

Genetic Architecture Of Charcoal Rot (Macrophomina Phaseolina) Resistance In Soybean Revealed Using A Diverse Panel, Sara M. Coser, R. V. Chowda Reddy, Jiaoping Zhang, Daren S. Mueller, Alemu Mengistu, Kiersten A. Wise, Tom W. Allen, Arti Singh, Asheesh K. Singh

Agronomy Publications

Charcoal rot (CR) disease caused by Macrophomina phaseolina is responsible for significant yield losses in soybean production. Among the methods available for controlling this disease, breeding for resistance is the most promising. Progress in breeding efforts has been slow due to the insufficient information available on the genetic mechanisms related to resistance. Genome-wide association studies (GWAS) enable unraveling the genetic architecture of resistance and identification of causal genes. The aims of this study were to identify new sources of resistance to CR in a collection of 459 diverse plant introductions from the USDA Soybean Germplasm Core Collection using field and ...


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 ...


Isolation And Characterization Of The Aconitate Hydratase 4 (Aco4) Gene From Soybean, Z Coleman, J. Boelter, K. Espinosa, A. S. Goggi, R. G. Palmer, D. Sandhu Feb 2017

Isolation And Characterization Of The Aconitate Hydratase 4 (Aco4) Gene From Soybean, Z Coleman, J. Boelter, K. Espinosa, A. S. Goggi, R. G. Palmer, D. Sandhu

Agronomy Publications

Aconitase catalyzes the reversible isomerization of two tricarboxylic acids, citrate and isocitrate, during the Krebs cycle. Five aconitase genes, namely, Aco1, Aco2, Aco3, Aco4, and Aco5, have been identified in soybean. Previously, Aco4 was mapped on chromosome 11. The purpose of this investigation was to isolate and sequence the candidate gene for Aco4. We mapped the Aco4 gene to a 148 kb region on chromosome 11 that contained 19 predicted genes. One of these, Glyma.11G080600, codes for aconitate hydratase. Sequencing of two isozyme variants (A-line and B-line) for Glyma.11G080600 revealed three synonymous and two non-synonymous substitutions. Perhaps, the ...


Identification Of Spectral Disease Signatures And Resistant Qtl For Charcoal Rot Infection In Soybean, Sarah Jones Jan 2017

Identification Of Spectral Disease Signatures And Resistant Qtl For Charcoal Rot Infection In Soybean, Sarah Jones

Graduate Theses and Dissertations

Disease phenotyping is an important process for both production field scouting and disease rating in soybean [Glycine max (L.) Merr.] breeding programs because yield is affected by many pathogens including charcoal rot, Macrophomina phaseolina. Charcoal rot has limited chemical control options and affects over 500 species worldwide making crop rotation a difficult management strategy as well. Due to these management challenges, breeding for disease resistance is a valuable strategy, however traditional disease phenotyping relies on human visual ratings which are prone to human error and have scalability issues when moving to large production schemes or modern breeding programs. Furthermore, there ...


Advancing Our Understanding Of Charcoal Rot In Soybeans, Martha P. Romero Luna, Daren Mueller, Alemu Mengistu, Asheesh K. Singh, Glen L. Hartman, Kiersten A. Wise Jan 2017

Advancing Our Understanding Of Charcoal Rot In Soybeans, Martha P. Romero Luna, Daren Mueller, Alemu Mengistu, Asheesh K. Singh, Glen L. Hartman, Kiersten A. Wise

Agronomy Publications

Charcoal rot [Macrophomina phaseolina (Tassi) Goid] of soybean [Glycine max (L.) Merr.] is an important but commonly misidentified disease, and very few summary articles exist on this pathosystem. Research conducted over the past 10 yr has improved our understanding of the environment conducive to disease development, host resistance, and improved disease diagnosis and management. This article summarizes the currently available research with an emphasis on disease management.


Soybean Proteins Gmtic110 And Gmpsbp Are Crucial For Chloroplast Development And Function, Devinder Sandhu, Taylor Atkinson, Andrea Noll, Callie Johnson, Katherine Espinosa, Jessica Boelter, Stephanie Abel, Balpreet K. Dhatt, Terese Barta, Eric Singsaas, Sol Sepsenwol, A. Susana Goggi, Reid G. Palmer Nov 2016

Soybean Proteins Gmtic110 And Gmpsbp Are Crucial For Chloroplast Development And Function, Devinder Sandhu, Taylor Atkinson, Andrea Noll, Callie Johnson, Katherine Espinosa, Jessica Boelter, Stephanie Abel, Balpreet K. Dhatt, Terese Barta, Eric Singsaas, Sol Sepsenwol, A. Susana Goggi, Reid G. Palmer

Agronomy Publications

We have identified a viable-yellow and a lethal-yellow chlorophyll-deficient mutant in soybean. Segregation patterns suggested single-gene recessive inheritance for each mutant. The viable- and lethal-yellow plants showed significant reduction of chlorophyll aand b. Photochemical energy conversion efficiency and photochemical reflectance index were reduced in the viable-yellow plants relative to the wildtype, whereas the lethal-yellow plants showed no electron transport activity. The viable-yellow plants displayed reduced thylakoid stacking, while the lethal-yellow plants exhibited failure of proplastid differentiation into normal chloroplasts with grana. Genetic analysis revealed recessive epistatic interaction between the viable- and the lethal-yellow genes. The viable-yellow gene was mapped ...


Virus-Induced Gene Silencing And Transient Gene Expression In Soybean (Glycine Max) Using Bean Pod Mottle Virus Infectious Clones, Steven A. Whitham, Lori M. Lincoln, R. V. Chowda-Reddy, Jaime D. Dittman, Jamie A. O'Rourke, Michelle A. Graham Jun 2016

Virus-Induced Gene Silencing And Transient Gene Expression In Soybean (Glycine Max) Using Bean Pod Mottle Virus Infectious Clones, Steven A. Whitham, Lori M. Lincoln, R. V. Chowda-Reddy, Jaime D. Dittman, Jamie A. O'Rourke, Michelle A. Graham

Plant Pathology and Microbiology Publications

Virus-induced gene silencing (VIGS) is a powerful and rapid approach for determining the functions of plant genes. The basis of VIGS is that a viral genome is engineered so that it can carry fragments of plant genes, typically in the 200 to 300 base pair size range. The recombinant viruses are used to infect experimental plants, and wherever the virus invades, the target gene or genes will be silenced. VIGS is thus transient, and in the span of a few weeks, it is possible to design VIGS constructs and then generate loss-of-function phenotypes through RNA silencing of the target genes ...


Molecular Characterization Of Short And Long Term Iron Stress Responses In Soybean, Leorrie Ann Atencio Jan 2016

Molecular Characterization Of Short And Long Term Iron Stress Responses In Soybean, Leorrie Ann Atencio

Graduate Theses and Dissertations

Iron Deficiency Chlorosis (IDC) is a disease caused by lack of useable iron in the soil. Symptoms include stunting and interveinal chlorosis of the leaves, eventually leading to yield loss at the end of the season. IDC is particularly important in the upper Midwestern United States because soil conditions favor its development. With the use of next generation sequencing approaches, we characterized soybeans’ short and long-term response to iron stress. Our research takes advantage of two near isogenic lines that are 98% genetically identical but differ in their iron efficiency response. Clark plants are iron efficient, while Isoclark plants are ...


Rye Cover Crop Biomass, Nutrient Composition And Crop Management Practices To Enhance Corn Yield, Swetabh Patel Jan 2016

Rye Cover Crop Biomass, Nutrient Composition And Crop Management Practices To Enhance Corn Yield, Swetabh Patel

Graduate Theses and Dissertations

Winter cereal rye (Secale cereal L.), a commonly used cover crop in corn (Zea mays L.) systems has potential to scavenge soil NO3–N through a fibrous root system. The objective of this study was to quantify root and shoot biomass, C, and N partitioning in rye cover crop at the time of termination in spring. This was a one–year study conducted at a site with a no-till corn–soybean [Glycine max (L.) Merr.] rotation, rye drilled following grain crop harvest, and three N rates applied to corn (0, 135, and 225 kg N ha–1). Rye root biomass ...


Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel Barker, Ranae N. Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter Thorburn, Sotirios Archontoulis Jan 2016

Modeling Long-Term Corn Yield Response To Nitrogen Rate And Crop Rotation, Laila A. Puntel, John E. Sawyer, Daniel Barker, Ranae N. Dietzel, Hanna Poffenbarger, Michael J. Castellano, Kenneth J. Moore, Peter Thorburn, Sotirios Archontoulis

Agronomy Publications

Improved prediction of optimal N fertilizer rates for corn (Zea mays L.) can reduce N losses and increase profits. We tested the ability of the Agricultural Production Systems sIMulator (APSIM) to simulate corn and soybean (Glycine max L.) yields, the economic optimum N rate (EONR) using a 16-year field-experiment dataset from central Iowa, USA that included two crop sequences (continuous corn and soybean-corn) and five N fertilizer rates (0, 67, 134, 201, and 268 kg N ha-1) applied to corn. Our objectives were to: (a) quantify model prediction accuracy before and after calibration, and report calibration steps; (b) compare ...


Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi Jan 2016

Candidate Perennial Bioenergy Grasses Have A Higher Albedo Than Annual Row Crops, Jesse N. Miller, Andy Vanloocke, Nuria Gomez-Casanovas, Carl J. Bernacchi

Agronomy Publications

The production of perennial cellulosic feedstocks for bioenergy presents the potential to diversify regional economies and the national energy supply, while also serving as climate ‘regulators’ due to a number of biogeochemical and biogeophysical differences relative to row crops. Numerous observational and model-based approaches have investigated biogeochemical trade-offs, such as increased carbon sequestration and increased water use, associated with growing cellulosic feedstocks. A less understood aspect is the biogeophysical changes associated with the difference in albedo (a), which could alter the local energy balance and cause local to regional cooling several times larger than that associated with offsetting carbon. Here ...


Survey Of Soybean Insect Pollinators: Community Identification And Sampling Method Analysis, K. A. Gill, M. E. O'Neal Jun 2015

Survey Of Soybean Insect Pollinators: Community Identification And Sampling Method Analysis, K. A. Gill, M. E. O'Neal

Entomology Publications

Soybean, Glycine max (L.) Merrill, flowers can be a source of nectar and pollen for honey bees, Apis mellifera L. (Hymenoptera: Apidae), wild social and solitary bees (Hymenoptera: Apoidea), and flower-visiting flies (Diptera). Our objectives were to describe the pollinator community in soybean fields, determine which sampling method is most appropriate for characterizing their abundance and diversity, and gain insight into which pollinator taxa may contact soybean pollen. We compared modified pan traps (i.e., bee bowls), yellow sticky traps, and sweep nets for trapping pollinators in Iowa soybean fields when soybeans were blooming (i.e., reproductive stages R1–R6 ...


Evaluation Of Spontaneous Generation Of Allelic Variation In Soybean In Response To Sexual Hybridization And Stress, Katherine Espinosa, Jessica Boelter, Susan Lolle, Marianne Hopkins, Susana Goggi, Reid G. Palmer, Devinder Sandhu Mar 2015

Evaluation Of Spontaneous Generation Of Allelic Variation In Soybean In Response To Sexual Hybridization And Stress, Katherine Espinosa, Jessica Boelter, Susan Lolle, Marianne Hopkins, Susana Goggi, Reid G. Palmer, Devinder Sandhu

Agronomy Publications

Intra-cultivar variation reported in pure lines of soybean has been hypothesized to result from genetic mechanisms contributing to de novo genetic variation. In this study we have detected allele switching by following segregation pattern of Aconitase-4 isozyme in sexual crosses and pure lines. In sexual crosses, one F2 plant showed switch at the Aconitase- 4 (Aco4) locus from the expected heterozygous genotype Aco4-ac to Aco4-ab. In the pure lines grown in a honeycomb planting design and treated with an accelerated aging test, multiple cases of allele switching were detected at the Aco4 locus. Both single and double switches were detected ...


Influence Of Bradyrhizobium Inoculation And Fungicide Treatment On Development And Yield Of Selected Pulse Crops; Nutritional Composition Of Pulse Legume Leaves And The Impact Of Leaf Removal On Yield, Rosemary Bulyaba Jan 2015

Influence Of Bradyrhizobium Inoculation And Fungicide Treatment On Development And Yield Of Selected Pulse Crops; Nutritional Composition Of Pulse Legume Leaves And The Impact Of Leaf Removal On Yield, Rosemary Bulyaba

Graduate Theses and Dissertations

Part 1

Declining soil fertility due to inadequate nitrogen in most soils limits farmers’ goals of increasing yield. There is environmental and agricultural benefit of reducing dependence on nitrogen fertilizer by emphasizing adaptation of favorable farming practices that minimize nitrogen fertilizer. Cowpea [Vigna unguiculata (L.) Walp.] and lablab (Lablab purpureus (L.)] are pulses with potential for grain, forage, and cover crops in the Midwest of United States, but little is known about their growth, development, and productivity potential in Iowa. We conducted a two-year field study to determine the influence of rhizobia inoculation and fungicide seed treatment of selected pulses ...


Plant Tissue Analysis To Assess Phosphorus And Potassium Nutritional Status Of Corn And Soybean In Iowa, Andrew John Stammer Jan 2015

Plant Tissue Analysis To Assess Phosphorus And Potassium Nutritional Status Of Corn And Soybean In Iowa, Andrew John Stammer

Graduate Theses and Dissertations

Interest in re-evaluating the value of tissue testing to assess P and K status in corn (Zea mays L.) and soybean (Glycine max L. Merr.) is increasing. The objective of this research was to study relationships between grain yield response to P and K and the concentration of these nutrients in plant tissue. Single-year and multi-year response trials were conducted in Iowa at 30 sites for P (32 sites-years with corn and 34 with soybean) and at 53 for K (67 sites years with corn and 52 with soybean) that encompassed 17 soil series. We sampled above-ground plant parts at ...


Candidate Gene Identification For A Lethal Chlorophyll-Deficient Mutant In Soybean, Sam Reed, Taylor Atkinson, Carly Gorecki, Katherine Espinosa, Sarah Przybylski, Alcira Susana Goggi, Reid G. Palmer, Devinder Sandhu Jan 2014

Candidate Gene Identification For A Lethal Chlorophyll-Deficient Mutant In Soybean, Sam Reed, Taylor Atkinson, Carly Gorecki, Katherine Espinosa, Sarah Przybylski, Alcira Susana Goggi, Reid G. Palmer, Devinder Sandhu

Agronomy Publications

Chlorophyll-deficient mutants have been studied persistently to understand genetic mechanisms controlling metabolic pathways. A spontaneous chlorophyll-deficient lethal mutant was observed in self-pollinated progeny of a soybean cultivar “BSR 101”. Observed segregation patterns indicated single-gene recessive inheritance for this lethal-yellow mutant. The objectives of this investigation were to develop a genetic linkage map of the region containing the lethal-yellow (YL_PR350) gene and identify putative candidate genes for this locus. The YL_PR350 gene was mapped to chromosome 15 and is flanked by BARCSOYSSR_15_1591 and BARCSOYSSR_15_1597. This region physically spans ~153 kb and there are 14 predicted genes that lie in this region ...