Life Sciences Commons^™

Extension Agriculture And Natural Resources In The U.S. Midwest: A Review And Analysis Of Challenges And Future Opportunities, Mahdi M. Al-Kaisi, Roger Wesley Elmore, Gerald A. Miller, David Kwaw-Mensah

Department of Agronomy and Horticulture: Faculty Publications

This review addresses key changes in U.S. agricultural extension and future opportunities. Agricultural extension has been a part of the land-grant university (LGU) system for more than 100 years. The Morrill Act of 1862 established the LGU system by authorizing states access to federally controlled land and funding for public institutions offering educational opportunities focusing on agriculture and mechanical arts for farmers and the working class. Current surveys in Iowa reveal changing trends in extension: more than 90% of farmers identified private-sector crop advisers as their primary source for recommendations, whereas more than 80% of those advisors identified Iowa State …

Soybean Yield And Nodulation Response To Crop History And Inoculation, Stephen Mason, Tomie Galusha, Zaher Kmail

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] inoculation was imposed on a long-term continuous grain sorghum [Sorghum bicolor (L.) Moench] and soybean cropping systems study with and without manure application at Mead, NE. The objective was to determine the influence of 28-yr history of continuous grain sorghum and soybean production, inoculation, and manure on soybean yield and nodulation. Average 2-yr soybean grain yield was 0.5 Mg ha^–1 greater on plots with continuous grain sorghum crop history rather than soybean history, even after this history was broken by 2-yr crop rotation with grain sorghum in the 2 yr previous to …

Soil Moisture Affects Growing-Season Wildfire Size In The Southern Great Plains, Erik S. Krueger, Tyson E. Ochsner, David M. Engle, J. D. Carlson, Dirac L. Twidwell, Samuel D. Fuhlendorf

Department of Agronomy and Horticulture: Faculty Publications

The increasing availability of soil moisture data presents an opportunity for its use in wildfire danger assessments, but research regarding the influence of soil moisture on wildfires is scarce. Our objective was to identify relationships between soil moisture and wildfire size for Oklahoma wildfires during the growing (May-October) and dormant seasons (November-April). We hypothesized that soil moisture influences wildfire size when vegetation is growing but is less important when most vegetation is dead or dormant. Soil moisture, as fraction of available water capacity (FAW), and commonly measured weather variables were determined for 38,419 wildfires from 2000–2012. Wildfires were grouped by …

Distribution Of Herbicide-Resistant Shattercane And Johnsongrass Populations In Sorghum Production Areas Of Nebraska And Northern Kansas, Rodrigo Werle, Amit J. Jhala, Melinda K. Yerka, J. Anita Dille, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Overreliance on acetolactate synthase (ALS)-inhibiting herbicides for weed control during the 1990s resulted in selection of ALS-resistant shattercane [Sorghum bicolor (L.) Moench ssp. drummondii (Nees ex Steud.) de Wet ex Davidse] biotypes in Nebraska. The objective of this study was to assess the baseline presence of ALS-resistance in 190 shattercane and 59 johnsongrass [Sorghum halepense (L.) Pers.] populations collected across northern Kansas, northwestern Missouri, and southern Nebraska in 2013. In 2014, a preliminary field experiment was conducted to evaluate the presence of herbicide resistance in the aforementioned populations. Treatments consisted of four herbicides (clethodim {2-[1-[[(E)-3-chloroprop-2-enoxy]amino] propylidene]-5-(2-ethylsulfanylpropyl)cyclohexane-1,3-dione}, glyphosate [N-(phosphonomethyl) …

Genetic Control Of Morphometric Diversity In The Maize Shoot Apical Meristem, Samuel Leiboff, Xianran Li, Heng-Cheng Hu, Natalie Todt, Jinliang Yang, Xiao Li, Xiaoqing Yu, Gary J. Muehlbauer, Marja C.P. Timmermans, Jianming Yu, Patrick S. Schnable, Michael J. Scanlon

Department of Agronomy and Horticulture: Faculty Publications

The maize shoot apical meristem (SAM) comprises a small pool of stem cells that generate all above-ground organs. Although mutational studies have identified genetic networks regulating SAM function, little is known about SAM morphological variation in natural populations. Here we report the use of high-throughput image processing to capture rich SAM size variation within a diverse maize inbred panel. We demonstrate correlations between seedling SAM size and agronomically important adult traits such as flowering time, stem size and leaf node number. Combining SAM phenotypes with 1.2 million single nucleotide polymorphisms (SNPs) via genome-wide association study reveals unexpected SAM morphology candidate …

Residue Harvest Effects On Irrigated, No-Till Corn Yield And Nitrogen Response, Charles S. Wortmann, Charles A. Shapiro, Marty R. Schmer

Department of Agronomy and Horticulture: Faculty Publications

Crop residue harvest occurs on about 40% of Nebraska’s 3,700,000 ha of corn (Zea mays L.) land, primarily for feeding of beef cattle. Immobilization of applied N is expected to be less with residue harvest due to reduced microbial activity for digestion of high C/N ratio organic material. Residue reduction may affect subsequent crop yield and response to applied N. Field research was conducted at three locations over 2 yr in eastern Nebraska for irrigated, no-till corn following corn to determine residue harvest effects on yield and the economically optimal nitrogen rate (EONR). Study sites had deep silt loam …

Herbicides Applied At Or Shortly After Seeding Are Effective For Weed Control In Seedling Buffalograss, Luqi Li, Matthew D. Sousek, Zachary Reicher

Department of Agronomy and Horticulture: Faculty Publications

Herbicides applied shortly after seeding of buffalograss [Buchloe dactyloides (Nutt.) Engelm.] can help reduce weed pressure and maximize establishment of buffalograss. This study evaluated 12 relatively recently developed herbicides for turf safety and weed control when applied at seeding or 0 or 2 weeks after emergence (WAE) of ‘Bowie’ or ‘Sundancer’ buffalograss. Primary weed species on the site were common purslane (Portulaca oleracea L.), redroot pigweed (Amaranthus retroflexus L.), and/or yellow foxtail [Setaria lutescens (Weigel ex Stuntz) F.T. Hubb.]. Regardless of cultivar, untreated checks had53% weed cover by 6 WAE, whereas most of the herbicide treatments resulted …

Synfind: Compiling Syntenic Regions Across Any Set Of Genomes On Demand, Haibao Tang, Matthew D. Bomhoff, Evan Briones, Liangsheng Zhang, James C. Schnable, Eric Lyons

Department of Agronomy and Horticulture: Faculty Publications

The identification of conserved syntenic regions enables discovery of predicted locations for orthologous and homeologous genes, evenwhennosuchgeneispresent.Thiscapabilitymeansthatsynteny-basedmethodsarefarmoreeffectivethansequencesimilaritybased methods in identifying true-negatives, a necessity forstudying gene loss and gene transposition. However, the identification of syntenicregionsrequirescomplexanalyseswhichmustberepeatedforpairwisecomparisonsbetweenanytwospecies.Therefore,as the number of published genomes increases, there is a growing demand for scalable, simple-to-use applications to perform comparative genomic analyses that cater to both gene family studies and genome-scale studies. We implemented SynFind, a web-based tool that addresses this need. Given one query genome, SynFind is capable of identifying conserved syntenic regions in any set of targetgenomes.SynFindiscapableofreportingper-geneinformation,usefulforresearchersstudyingspecificgenefamilies,aswellas genome-wide data sets of syntenic gene and predicted gene …

A Population Structure And Genome-Wide Association Analysis On The Usda Soybean Germplasm Collection, Nonoy Bandillo, Diego Jarquin, Qijian Song, Randall L. Nelson, Perry Cregan, James Specht, Aaron Lorenz

Department of Agronomy and Horticulture: Faculty Publications

Population structure analyses and genome-wide association studies (GWAS) conducted on crop germplasm collections provide valuable information on the frequency and distribution of alleles governing economically important traits. The value of these analyses is substantially enhanced when the accession numbers can be increased from ~1,000 to ~10,000 or more. In this research, we conducted the first comprehensive analysis of population structure on the collection of 14,000 soybean accessions [Glycine max (L.) Merr. and G. soja Siebold & Zucc.] using a 50KSNP chip. Accessions originating from Japan were relatively homogenous and distinct from the Korean accessions. As a whole, both Japanese and …

Adding Genetically Distant Individuals To Training Populations Reduces Genomic Prediction Accuracy In Barley, Aaron Lorenz, Kevin P. Smith

Department of Agronomy and Horticulture: Faculty Publications

One of the most important factors affecting genomic prediction accuracy appears to be training population (TP) composition. The objective of this study was to evaluate the effect of genomic relationship on genomic prediction accuracy and determine if adding increasingly unrelated individuals to a TP can reduce prediction accuracy. To accomplish this, a population of barley (Hordeum vulgare L.) lines from the University of Minnesota (lines denoted as MN) and North Dakota State University (lines denoted as ND) breeding programs were used for model training. Predictions were validated using two independent sets of progenies derived from MN  MN crosses …

Community Seed Banks: Origins, Evolution, And Prospects, Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

As a survey of contemporary community-level seed banks, this is an excellent compilation and instructive guide. The first section provides an overview of how seed banks originated, their varied goals and activities, several contrasting forms of management, and how they organize and perform to meet these goals. An intriguing claim in the book is that the concept of “seed banks is only some three decades old,” while in fact the practice of saving, preserving, and exchanging seed within a community is probably as old as human communities themselves.

Organized seed banks often serve specific functions: preserving seeds, providing seed access …

Switchgrass Germplasm Resources, Michael D. Casler, Kenneth P. Vogel, Melanie Harrison

Department of Agronomy and Horticulture: Faculty Publications

Switchgrass (Panicum virgatum L.) is an important native grass and dominant member of the tallgrass prairie ecosystem. It is used for conservation, restoration, livestock feed production, and bioenergy feedstock production. The purpose of this review is to describe the biological and geographical basis for switchgrass germplasm diversity and to provide a resource for scientists and outreach personnel to find switchgrass germplasm to meet their needs. Upland and lowland ecotypes represent the most important polymorphism in switchgrass, with distinct but overlapping geographic distributions. Variation in ploidy exists within both ecotypes, with 2n = 4x = 36 the dominant ploidy …

Occurrence Of An Herbicide-Resistant Plant Trait In Agricultural Field Margins, Karla L. Gag, David J. Gibson, Bryan G. Young, Julie M. Young, Joseph L. Matthews, Stephen C. Weller, Robert G. Wilson

Department of Agronomy and Horticulture: Faculty Publications

Agricultural environments allow study of evolutionary change in plants. An example of evolution within agroecological systems is the selection for resistance to the herbicide glyphosate within the weed, Conyza canadensis. Changes in survivorship and reproduction associated with the development of glyphosate resistance (GR) may impact fitness and influence the frequency of occurrence of the GR trait. We hypothesized that site characteristics and history would affect the occurrence of GR C. canadensis in field margins. We surveyed GR occurrence in field margins and asked whether there were correlations between GR occurrence and location, crop rotation, GR crop trait rotation, crop type, …

Comparing Yield Monitors With Weigh Wagons For On-Farm Corn Hybrid Evaluation, Bjorn P. Nelson, Roger Wesley Elmore, Andrew W. Lenssen

Department of Agronomy and Horticulture: Faculty Publications

For many years, on-farm yield evaluations of corn (Zea mays L.) hybrids were done with weigh wagons, handheld moisture testers, and measuring wheels. Today, most combines have continuous flow yield and moisture sensors. Published research results comparing the accuracy of combine-mounted sensor systems with that of weigh wagons are limited for on-farm corn hybrid evaluation. This study examined the accuracy of combine-mounted yield sensors with traditional weigh wagon methodology in on-farm corn hybrid strip trials. Data from combine-mounted sensors for plot weight, moisture percentage, and yield were compared with weigh wagon weight, handheld moisture testers, and calculated yield …

Microsatellite Variations Of Elite Setaria Varieties Released During Last Six Decades In China, Guanqing Jia, Xiaotong Liu, James C. Schnable, Zhengang Niu, Chunfang Wang, Yuhui Li, Shujun Wang, Suying Wang, Jinrong Liu, Erhu Guo, Hui Zhi, Xianmin Diao

Department of Agronomy and Horticulture: Faculty Publications

Crop improvement is a multifaceted micro-evolutionary process, involving changes in breeding approaches, planting configurations and consumption preferences of human beings. Recent research has started to identify the specific genes or genomic regions correlate to improved agronomic traits, however, an apparent blank between the genetic structure of crop elite varieties and their improving histories in diverse modern breeding programs is still in existence. Foxtail millet (Setaria italica) was one of the earliest cereal crops to be domesticated and served as a staple crop for early civilizations in China, where it is still widely grown today. In the present trial, …

Evaluation And Association Mapping Of Resistance To Tan Spot And Stagonospora Nodorum Blotch In Adapted Winter Wheat Germplasm, Zhaohui Liu, Ibrahim El-Basyoni, Gayan Kariyawasam, Guorong Zhang, Allan Fritz, Jana Hansen, Francois Marais, Andrew Friskop, Shiaoman Chao, Eduard Akhunov, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Tan spot and Stagonospora nodorum blotch (SNB), often occurring together, are two economically significant diseases of wheat in the Northern Great Plains of the United States. They are caused by the fungi Pyrenophora tritici-repentis and Parastagonospora nodorum, respectively, both of which produce multiple necrotrophic effectors (NE) to cause disease. In this work, 120 hard red winter wheat (HRWW) cultivars or elite lines, mostly from the United States, were evaluated in the greenhouse for their reactions to the two diseases as well as NE produced by the two pathogens. One P. nodorum isolate (Sn4) and four Pyrenophora tritici-repentis isolates (Pti2, …

Evaluating A Satellite-Based Seasonal Evapotranspiration Product And Identifying Its Relationship With Other Satellite-Derived Products And Crop Yield: A Case Study For Ethiopia, Tsegaye Tadesse, Gabriel B. Senay, Getachew Berhan, Teshome Regassa, Shimelis Beyene

Department of Agronomy and Horticulture: Faculty Publications

Satellite-derived evapotranspiration anomalies and normalized difference vegetation index (NDVI) products from Moderate Resolution Imaging Spectroradiometer (MODIS) data are currently used for African agricultural drought monitoring and food security status assessment. In this study, a process to evaluate satellite-derived evapotranspiration (ETa) products with a geospatial statistical exploratory technique that uses NDVI, satellite-derived rainfall estimate (RFE), and crop yield data has been developed. The main goal of this study was to evaluate the ETa using the NDVI and RFE, and identify a relationship between the ETa and Ethiopia’s cereal crop (i.e., teff, sorghum, corn/maize, barley, and wheat) yields during the main rainy …

Characterization Of Novel Sorghum Brown Midrib Mutants From An Ems-Mutagenized Population, Scott E. Sattler, Ana Saballos, Zhanguo Xin, Deanna L. Funnell-Harris, Wilfred Vermerris, Jeffrey F. Pedersen

Department of Agronomy and Horticulture: Faculty Publications

Reducing lignin concentration in lignocellulosic biomass can increase forage digestibility for

ruminant livestock and saccharification yields of biomass for bioenergy. In sorghum (Sorghum bicolor (L.) Moench) and several other C4 grasses, brown midrib (bmr) mutants have been shown to reduce lignin concentration. Putative bmr mutants isolated from an EMS-mutagenized population were characterized and classified based on their leaf midrib phenotype and allelism tests with the previously described sorghum bmr mutants bmr2, bmr6, and bmr12. These tests resulted in the identification of additional alleles of bmr2, bmr6, and bmr12, and, in addition, six bmr …

A Roadmap For Functional Structural Variants In The Soybean Genome, Justin E. Anderson, Michael B. Kantar, Thomas Y. Kono, Fengli Fu, Adrian O. Stec, Qijian Song, Perry B. Cregan, James E. Specht, Brian W. Diers, Steven B. Cannon, Leah K. Mchale, Robert M. Stupar

Department of Agronomy and Horticulture: Faculty Publications

Gene structural variation (SV) has recently emerged as a key genetic mechanism underlying several important phenotypic traits in crop species. We screened a panel of 41 soybean (Glycine max) accessions serving as parents in a soybean nested association mapping population for deletions and duplications in more than 53,000 gene models. Array hybridization and whole genome resequencing methods were used as complementary technologies to identify SV in 1528 genes, or approximately 2.8%, of the soybean gene models. Although SV occurs throughout the genome, SV enrichment was noted in families of biotic defense response genes. Among accessions, SV was nearly eightfold less …

Selection For Silage Yield And Composition Did Not Affect Genomic Diversity Within The Wisconsin Quality Synthetic Maize Population, Aaron Lorenz, Timothy M. Beissinger, Renato Rodrigues Silva, Natalia De Leon

Department of Agronomy and Horticulture: Faculty Publications

Maize silage is forage of high quality and yield, and represents the second most important use of maize in the United States. The Wisconsin Quality Synthetic (WQS) maize population has undergone five cycles of recurrent selection for silage yield and composition, resulting in a genetically improved population. The application of high-density molecular markers allows breeders and geneticists to identify important loci through association analysis and selection mapping, as well as to monitor changes in the distribution of genetic diversity across the genome. The objectives of this study were to identify loci controlling variation for maize silage traits through association analysis …

Overexpression Of The Transporters Atzip1 And Atmtp1 In Cassava Changes Zinc Accumulation And Partitioning, Eliana Gaitán-Solis, Nigel J. Taylor, Dimuth Siritunga, William Stevens, Daniel P. Schachtman

Department of Agronomy and Horticulture: Faculty Publications

Zinc deficiency in humans is a serious problem worldwide with an estimated one third of populations at risk for insufficient zinc in diet, which leads to impairment of cognitive abilities and immune system function. The goal of this research was to increase the bioavailable zinc in the edible portion of cassava roots to improve the overall zinc nutrition of populations that rely on cassava as a dietary staple. To increase zinc concentrations, two Arabidopsis thaliana genes coding for ZIP1 and MTP1 were overexpressed with a tuber-specific or constitutive promoter. Eighteen transgenic events from four constructs, out of a total of …

Patch Burning: Implications On Water Erosion And Soil Properties, Altingul Ozaslan Parlak, Mehmet Parlak, Humberto Blanco-Canqui, Walter H. Schacht, John A. Guretzky, Martha Mamo

Department of Agronomy and Horticulture: Faculty Publications

Patch burning can be a potential management tool to create grassland heterogeneity and enhance forage productivity and plant biodiversity, but its impacts on soil and environment have not been widely documented. In summer 2013, we studied the effect of time after patch burning (4 mo after burning [recently burned patches], 16 mo after burning [older burned patches], and unburned patches [control]) on vegetative cover, water erosion, and soil properties on a patch-burn experiment established in 2011 on a Yutan silty clay loam near Mead, NE. The recently burned patches had 29 ± 8.0% (mean ± SD) more bare ground, 21 …

First Approximations Of Prescribed Fire Risks Relative To Other Management Techniques Used On Private Lands, Dirac L. Twidwell, Carissa L. Wonkka, Michael T. Sindelar, John R. Weir

Department of Agronomy and Horticulture: Faculty Publications

Fire is widely recognized as a critical ecological and evolutionary driver that needs to be at the forefront of land management actions if conservation targets are to be met. However, the prevailing view is that prescribed fire is riskier than other land management techniques. Perceived risks associated with the application of fire limits its use and reduces agency support for prescribed burning in the private sector. As a result, considerably less cost-share support is given for prescribed fire compared to mechanical techniques. This study tests the general perception that fire is a riskier technique relative to other land management options. …

Differential Expression Analysis In Rna-Seq By A Naive Bayes Classifier With Local Normalization, Yongchao Dou, Xiaomei Guo, Lingling Yuan, David R. Holding, Chi Zhang

Department of Agronomy and Horticulture: Faculty Publications

To improve the applicability of RNA-seq technology, a large number of RNA-seq data analysis methods and correction algorithms have been developed. Although these new methods and algorithms have steadily improved transcriptome analysis, greater prediction accuracy is needed to better guide experimental designs with computational results. In this study, a new tool for the identification of differentially expressed genes with RNA-seq data, named GExposer, was developed. This tool introduces a local normalization algorithm to reduce the bias of nonrandomly positioned read depth. The naive Bayes classifier is employed to integrate fold change, transcript length, and GC content to identify differentially expressed …

Plants Coping Abiotic And Biotic Stresses: A Tale Of Diligent Management, Hatem Rouached, Sikander Pal, Shimon Rachmilevitch, Marc Libault, Lam-Son Phan Tran

Department of Agronomy and Horticulture: Faculty Publications

Plants unlike other living forms are sessile thereby facing severe biotic and abiotic stresses. Plants have evolved different efficient defence responses which thrive upon a number of intrinsic factors, such as genotypic and phenotypic constitutions and developmental circumstances, and extrinsic factors like severity and duration of the stresses. Stress management uses molecular and biochemical level controls, the competence, and speed, at which a stress signal is perceived and transmitted to generate stress signal molecules and activate stress-protective mechanisms. A well-concerted action of the plants’ competence at morphological, physiological, biochemical, and molecular strata regulates numerous adaptive responses to biotic and abiotic …

Calibration And Validation Of The Hybrid-Maize Crop Model For Regional Analysis And Application Over The U.S. Corn Belt, Xing Liu, Jeff Andresen, Haishun Yang, Dev Niyogi

Department of Agronomy and Horticulture: Faculty Publications

Detailed parameter sensitivity, model validation, and regional calibration of the Hybrid-Maize crop model were undertaken for the purpose of regional agroclimatic assessments. The model was run at both field scale and county scale. The county-scale study was based on 30-yr daily weather data and corn yield data from the National Agricultural Statistics Service survey for 24 locations across the Corn Belt of the United States. The field-scale study was based on AmeriFlux sites at Bondville, Illinois, andMead, Nebraska. By using the one-at-a-time and interaction-explicit factorial design approaches for sensitivity analysis, the study found that the five most sensitive parameters of …

High Tunnel Design, Site Development, And Construction, Stacy A. Adams, Kim Todd

Department of Agronomy and Horticulture: Faculty Publications

High tunnels are low technology plant growing structures that provide opportunity for season extension, severe weather protection, and modified environments to increase productivity and visual quality of harvested plant products. This publication describes high tunnel components, site selection, development, covering materials, installation, and operation.

Experienced specialty plant growers can increase the quality of their products and the duration of their marketing of high- value crops through the use of high tunnels. High tunnels give growers the opportunity to plant earlier and include more sequential planting dates. This can result in early- season, high- dollar returns and the ability to offer …

Genetic And Molecular Characterization Of Submergence Response Identifies Subtol6 As A Major Submergence Tolerance Locus In Maize, Malachy T. Campbell, Christopher A. Proctor, Yongchao Dou, Aaron J. Schmitz, Piyaporn Phansak, Greg R. Kruger, Chi Zhang, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Maize is highly sensitive to short term flooding and submergence. Early season flooding reduces germination, survival and growth rate of maize seedlings. We aimed to discover genetic variation for submergence tolerance in maize and elucidate the genetic basis of submergence tolerance through transcriptional profiling and linkage analysis of contrasting genotypes. A diverse set of maize nested association mapping (NAM) founder lines were screened, and two highly tolerant (Mo18Wand M162W) and sensitive (B97 and B73) genotypes were identified. Tolerant lines exhibited delayed senescence and lower oxidative stress levels compared to sensitive lines. Transcriptome analysis was performed on these inbreds to provide …

Allmaps: Robust Scaffold Ordering Based On Multiple Maps, Haibo Tang, Xingtan Zhang, Chenyong Miao, Jisen Zhang, Ray Ming, James C. Schnable, Patrick S. Schnable, Eric Lyons, Jianguo Lu

Department of Agronomy and Horticulture: Faculty Publications

The ordering and orientation of genomic scaffolds to reconstruct chromosomes is an essential step during de novo genome assembly. Because this process utilizes various mapping techniques that each provides an independent line of evidence, a combination of multiple maps can improve the accuracy of the resulting chromosomal assemblies. We present ALLMAPS, a method capable of computing a scaffold ordering that maximizes colinearity across a collection of maps. ALLMAPS is robust against common mapping errors, and generates sequences that are maximally concordant with the input maps. ALLMAPS is a useful tool in building high-quality genome assemblies. ALLMAPS is available at: https://github.com/tanghaibao/jcvi/wiki/ALLMAPS.

Identification Of Novel Qtl Governing Root Architectural Traits In An Interspecific Soybean Population, Lakshmi P. Manavalan, Silvas J. Prince, Theresa A. Musket, Julian Chaky, Rupesh Deshmukh, Tri D. Vuong, Li Song, Perry B. Cregan, James C. Nelson, J. Grover Shannon, James E. Specht, Henry T. Nguyen

Department of Agronomy and Horticulture: Faculty Publications

Cultivated soybean (Glycine max L.) cv. Dunbar (PI 552538) and wild G. soja (PI 326582A) exhibited significant differences in root architecture and root-related traits. In this study, phenotypic variability for root traits among 251 BC₂F₅ backcross inbred lines (BILs) developed from the cross Dunbar/PI 326582A were identified. The root systems of the parents and BILs were evaluated in controlled environmental conditions using a cone system at seedling stage. The G. max parent Dunbar contributed phenotypically favorable alleles at a major quantitative trait locus on chromosome 8 (Satt315-I locus) that governed root traits (tap root length and …