Life Sciences Commons^™

Simulated Winter Incubation Of Soil With Swine Manure Differentially Affects Multiple Antimicrobial Resistance Elements, Daniel N. Miller, Madison E. Jurgens, Lisa M. Durso, Amy Schmidt

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Gastrointestinal bacteria that harbor antibiotic resistance genes (ARG) become enriched with antibiotic use. Livestock manure application to cropland for soil fertility presents a concern that ARG and bacteria may proliferate and be transported in the environment. In the United States, manure applications typically occur during autumn with slow mineralization until spring planting season. A laboratory soil incubation study was conducted mimicking autumn swine manure application to soils with concentrations of selected ARG monitored during simulated 120-day winter incubation with multiple freeze-thaw events. Additionally, the effects of two soil moistures [10 and 30% water holding capacity (WHC)] and two manure treatments …

Measured And Simulated Carbon Dynamics In Midwestern U.S. Corn‐Soybean Rotations, C Dold, K M. Wacha, T J. Sauer, J L. Hatfield, J H. Prueger

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) production dominate Midwestern U.S. agriculture and impact the regional carbon and nitrogen cycles. Sustaining soil carbon is important for corn‐soybean production (CS); however, quantifying soil carbon changes requires long‐term field measurements and/or model simulations. In this study, changes in soil organic (SOC), inorganic (SIC), and total (TC) carbon; pH; total nitrogen (TN); and net ecosystem production (NEP) were measured in a conventional corn‐soybean rotation in central Iowa. Soil samples (n = 42; 0–120 cm depth) were collected from two adjacent fields in 2005 and 2016. Eddy‐flux stations set up in …

Energy Balance In The Dssat-Csm-Cropgro Model, Santiago V. Cuadra, Bruce A. Kimball, Kenneth J. Boote, Andrew E. Suyker, Nigel Pickering

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

One potential way to improve crop growth models is for the models to predict energy balance and evapotranspiration (ET) from first principles, thus serving as a check on “engineered” ET methodology. In this paper, we present new implementations and the results of an energy balance model (EBL) developed by Jagtap and Jones (1989) and then implemented in DSSAT’s CROPGRO (CG-EBL) model by Pickering et al. (1995) as a linked energy balance-photosynthesis model that has not been field-tested until now. The energy balance code computes evapotranspiration and other energy balance components, as well as a canopy air temperature, based on three …

Registration Of ‘Purple Bounty’ And ‘Purple Prosperity’ Hairy Vetch, Virginia Mae Moore, Jude E. Maul, Dave Wilson, William S. Curran, Daniel C. Brainard, Thomas E. Devine, Steven B. Mirsky

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The hairy vetch (Vicia villosa Roth) cultivars ‘Purple Bounty’ (Reg. no. CV-12, PI 648342) and ‘Purple Prosperity’ (Reg. no. CV-11, PI 654047) were released in 2007 and 2008, respectively, by the USDA–ARS in collaboration with the Rodale Institute and the agricultural experiment stations of Pennsylvania State University and Cornell University. Hairy vetch is a commonly used annual legume cover crop grown for its cold tolerance, fast growth, large biomass production, and ability to fix N2. However, this species has not been selected for the traits needed to optimize its use as a cover crop. Our breeding program focused on developing …

Agronomic Performance And Cooking Quality Characteristics For Slow-Darkening Pinto Beans, Phillip N. Miklas, Juan M. Osorno, Bernardo Chaves, Karen A. Cichy

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Slow-darkening (SD) pinto beans (Phaseolus vulgaris L.) possess a desirable new trait, conditioned by the recessive sd gene, that slows seed coat darkening under delayed harvest and under storage. The effect sd may have on performance needs investigation. We examined agronomic performance and cooking quality of SD pinto beans. There were 30 (15 SD and 15 regular darkening [RD]) recombinant inbred lines (RILs) from each of two biparental inbred populations. The 60 RILs were tested across three locations in North Dakota andWashington. In addition, advanced SD and RD pinto breeding lines were tested in trials from 2010 to 2012 and …

Description Of Baetao-Manteiga 41 And ‘Yunguilla’ Superior Andean Common Beans For Tanzanian Production Environments, S. Nchimbi Msolla, Phillip N. Miklas, D. Fourie, M. Kilango, T. Porch

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

An international effort was initiated with the evaluation of a diverse set of largeseeded Andean common beans (Phaseolus vulgaris L.), the Andean Diversity Panel, in sub-Saharan Africa. Several entries in the panel have been selected for extensive characterization on the basis of high performance acrossmultiple location × year trials in Tanzania—conducted both on station and on farm. Baetao- Manteiga 41, tested asADP-190, has a commercialKablanketi (light purple speckled) seed type, and ‘Yunguilla’, tested as ADP-447, has a commercial Calima (red mottled) seed type. Both lines exhibited yield stability, vigorous growth under low fertility conditions, angular leaf spot resistance, andmoderate …

Soil-Test Biological Activity With The Flush Of Co2: Viii. Soil Type And Management Diversity, Alan J. Franzluebbers, Mary R. Pershing

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Soil-test biological activity (STBA) is a key indicator describing the functions of soil to catabolize organic amendments, promote soil organic C sequestration, and cycle nutrients. We explored how climatic zone, land use, and physiographic region affected the relationship of STBA with several soil fertility properties and processes. Soils from Georgia, North Carolina, Pennsylvania, and Virginia (wet climate) were Aquults, Fluvents, Udalfs, Udepts, and Udults and soils from Nebraska and Oklahoma (dry climate) were Udolls and Ustolls. Annual cropland and perennial pasture were the land uses. The Prairie region had silt loam and silty clay loams, the Ridge–Valley region had silt …

Effects Of Combined Conservation Practices On Soil And Water Quality In The Central Mississippi River Basin, C. Baffaut, F. Ghidey, R. N. Lerch, K. S. Veum, E. J. Sadler, K. A. Sudduth, N. R. Kitchen

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Conventional cultivation of claypan soils leads to soil and water quality degradation because of high runoff and associated soil erosion. The Goodwater Creek Experimental Watershed, which is part of the USDA Agricultural Research Service Benchmark Conservation Effects Assessment Project, Watershed Assessment Studies, was established to address these issues. Plot studies have highlighted trade-offs between erosion control and herbicide or nutrient runoff. There is a need for long-term field-scale evaluation of combined practices that reduce sediment, nutrient, and herbicide losses by runoff. A 36 ha field located in Missouri was under a conventional corn (Zea mays L.)-soybean (Glycine max L.) system …

Horizontal Gene Transfer Of Fhb7 From Fungus Underlies Fusarium Head Blight Resistance In Wheat, Hongwei Wang, Silong Sun, Wenyang Ge, Lanfei Zhao, Bingqian Hou, Kai Wang, Zhongfan Lyu, Liyang Chen, Shoushen Xu, Jun Guo, Min Li, Peisen Su, Xuefeng Li, Guiping Wang, Cunyao Bo, Xiaojian Fang, Wenwen Zhuang, Xinxin Cheng, Jianwen Wu, Luhao Dong, Wuying Chen, Wen Li, Guilian Xiao, Jinxiao Zhao, Yongchao Hao, Ying Xu, Yu Gao, Wenjing Liu, Yanhe Liu, Huayan Yin, Jiazhu Li, Xiang Li, Yan Zhao, Xiaoqian Wang, Fei Ni, Xin Ma, Anfei Li, Steven S. Xu, Guihua Bai, Eviatar Nevo, Caixia Gao, Herbert Ohm, Lingrang Kong

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Fusarium head blight (FHB), a fungal disease caused by Fusarium species that produce food toxins, currently devastates wheat production worldwide, yet few resistance resources have been discovered in wheat germplasm. Here, we cloned the FHB resistance gene Fhb7 by assembling the genome of Thinopyrum elongatum, a species used in wheat distant hybridization breeding. Fhb7 encodes a glutathione S-transferase (GST) and confers broad resistance to Fusarium species by detoxifying trichothecenes through de-epoxidation. Fhb7 GST homologs are absent in plants, and our evidence supports that Th. elongatum has gained Fhb7 through horizontal gene transfer (HGT) from an endophytic Epichloë species. Fhb7 introgressions …

Genetic Associations In Four Decades Of Multienvironment Trials Reveal Agronomic Trait Evolution In Common Bean, Alice H. Macqueen, Jeffrey W. White, Rian Lee, Juan M. Osorno, Jeremy Schmutz, Phillip N. Miklas, Jim Myers, Phillip E. Mcclean, Thomas E. Juenger

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Multienvironment trials (METs) are widely used to assess the performance of promising crop germplasm. Though seldom designed to elucidate genetic mechanisms, MET data sets are often much larger than could be duplicated for genetic research and, given proper interpretation, may offer valuable insights into the genetics of adaptation across time and space. The Cooperative Dry Bean Nursery (CDBN) is a MET for common bean (Phaseolus vulgaris) grown for . 70 years in the United States and Canada, consisting of 20–50 entries each year at 10–20 locations. The CDBN provides a rich source of phenotypic data across entries, years, and locations …

Long-Term Rotation Diversity And Nitrogen Effects On Soil Organic Carbon And Nitrogen Stocks, Marty R. Schmer, Virginia L. Jin, Brian J. Wienhold, Sophia M. Becker, Gary E. Varvel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Understanding the impacts of long-term fertilizer management and rotation diversity on soil C and N is needed under a changing climate. The objective of this study was to evaluate the effects of N fertilizer level and crop rotation diversity on soil organic carbon (SOC) and soil N stocks from a 34-yr study located in eastern Nebraska. Seven crop rotations (three continuous cropping systems; two 2-yr crop rotations; and two 4-yr crop rotations) and three N levels were compared. Soil samples were taken to a depth of 150 cm. Differences in SOC stocks were largely confined to the 0- to 7.5-cm …

Registration Of Hard White Winter Wheat Germplasms Ks14u6380r5, Ks16u6380r10, And Ks16u6380r11 With Adult Plant Resistance To Stem Rust, Mary J. Guttieri, Robert L. Bowden, Katherine Reinhart, David S. Marshall, Yue Jin, Bradford W. Seabourn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Resistance to the Ug99 group of races of the stem rust fungus Puccinia graminis f. sp. tritici is limited in winter wheat (Triticum aestivum L.) germplasm adapted to the Great Plains of the United States. Our objective was to generate regionally adapted hard winter wheat germplasm with combinations of adult plant resistance genes that are expected to provide durable resistance. KS14U6380R5 (Reg. no. GP-1043, PI 689115), KS16U6380R10 (Reg. no. GP-1044, PI 689116), and KS16U6380R11 (Reg. no. GP-1045, PI 689117) were derived from backcrosses of the hard white winter wheat germplasm KS05HW14 to the stem rust-resistant Kenyan spring wheat cultivar ‘Kingbird’. …

Geographic Variation In The Genetic Basis Of Resistance To Leaf Rust Between Locally Adapted Ecotypes Of The Biofuel Crop Switchgrass (Panicum Virgatum), Acer Van Wallendael, Jason Bonnette, Thomas E. Juenger, Felix B. Fritschi, Philip A. Fay, Robert B. Mitchell, John Lloyd-Reilley, Francis M. Rouquette Jr, Gary C. Bergstrom, David B. Lowry

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Local adaptation is an important process in plant evolution, which can be impacted by differential pathogen pressures along environmental gradients. However, the degree to which pathogen resistance loci vary in effect across space and time is incompletely described.

To understand how the genetic architecture of resistance varies across time and geographic space, we quantified rust (Puccinia spp.) severity in switchgrass (Panicum virgatum) plantings at eight locations across the central USA for 3 yr and conducted quantitative trait locus (QTL) mapping for rust progression.

We mapped several variable QTLs, but two large-effect QTLs which we have named Prr1 and Prr2 were …

Soil Quality Indices Based On Long-Term Conservation Cropping Systems Management, Helen C.S. Amorim, Amanda J. Ashworth, Brian J. Wienhold, Mary C. Savin, Fred L. Allen, Arnold M. Saxton, Phillip R. Owens, Nilton Curi

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The Soil Management Assessment Framework (SMAF) may provide insight into how conservation practices affect soil quality (SQ) regionally. Therefore, we aimed to quantify SQ in a long-term (15-yr) crop rotation and bio-covers experiment under notillage using SMAF. Main effects were cropping rotations of soybean [Glycine max (L.) Merr.], corn (Zea mays L.), and cotton (Gossypium hirsutum L.). Split-block biocover treatments consisted of winter wheat (Triticum aestivum L.), Austrian winter pea (Pisum sativum L. sativum var. arvense), hairy vetch (Vicia villosa Roth), poultry litter, and fallow (control). Seven SQ indicators—soil pH, total organic carbon (TOC), bulk density (BD), soil extractable P …

Cropping System And Landscape Characteristics Influence Long-Term Grain Crop Profitability, L. S. Conway, M. A. Yost, Newell Kitchen, K. A. Sudduth, R. E. Massey, E. J. Sadler

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Converting from standard tillage or no-tillage cropping systems to more conservation-based cropping systems that include no-tillage, cover crops, and reduced agrichemical inputs must be profitable for large-scale adoption. Therefore, research was conducted at the central Mississippi River Basin site of the USDA Long-Term Agroecosystem Research Network from 1996 to 2009 to determine how cropping systems, landscape position, and depth to claypan affected net economic return. Treatments consisted of three cropping systems {mulch-till corn (Zea mays L.)–soybean [Glycine max (L.) Merr.], MTCS; no-till corn–soybean, NTCS; no-till corn–soybean–wheat (Triticum aestivum L.) (NTCSW)–cover crop} and three landscape positions (summit, backslope, and footslope). Within …

Estimation Of Maize Yield And Effects Of Variable-Rate Nitrogen Application Using Uav-Based Rgb Imagery, Meina Zhang, Jianfeng Zhou, Kenneth A. Sudduth, Newell R. Kitchen

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Accurate crop yield estimation is important for agronomic and economic decision-making. This study evaluated the performance of imagery data acquired using a unmanned aerial vehicle (UAV)-based imaging system for estimating yield of maize (Zea mays L.) and the effects of variable-rate nitrogen (N) application on crops. Images of a 27-ha maize field were captured using a UAV with a consumer-grade RGB camera flying at ~100 m above ground level at three maize growth stages. The collected sequential images were stitched and the Excess Green (ExG) colour feature was extracted to develop prediction models for maize yield and to examine the …

Genome-Wide Transcriptome And Physiological Analyses Provide New Insights Into Peanut Drought Response Mechanisms, Sailaja Bhogireddy, Abishek Xavier, International Crops Research Institute For The Semi-Arid Tropics (Icrisat), Hyderabad, India, Nancy Layland, Renee Arias, Paxton Payton, Spurthi N. Nayak, Manish K. Pandey, Naveen Puppala, Rajeev K. Varshney

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Drought is one of the main constraints in peanut production in West Texas and eastern New Mexico regions due to the depletion of groundwater. A multi-seasonal phenotypic analysis of 10 peanut genotypes revealed C76-16 (C-76) and Valencia-C (Val-C) as the best and poor performers under deficit irrigation (DI) in West Texas, respectively. In order to decipher transcriptome changes under DI, RNAseq was performed in C-76 and Val-C. Approximately 369 million raw reads were generated from 12 different libraries of two genotypes subjected to fully irrigated (FI) and DI conditions, of which ~329 million (90.2%) filtered reads were mapped to the …

Draft Genome Assembly Of Passalora Sequoiae A Needle Blight Pathogen On Leyland Cypress, Warren E. Copes, Jorge Ibarra Caballero, Ebrahiem Babiker, Jane E. Stewart, Valerie A. Orner, Alan S. Windham, Renee Arias

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Objective: Passalora sequoiae (family Mycosphaerellaceae) causes a twig blight on Leyland cypress that requires numerous fungicide applications annually to minimize economic losses for ornamental plant nursery and Christmas tree producers. The objective was to generate a high-quality draft assembly of the genome of P. sequoiae as a resource for primer development to investigate genotype diversity. Data description: We report here the genome sequence of P. sequoiae 9LC2 that was isolated from Leyland cypress ‘Leighton Green’ in 2017 in southern Mississippi, USA. The draft genome was obtained using Pacific Biosciences (PacBio) SMRT and Illumina HiSeq 2500 sequencing. Illumina reads were mapped …

Genetic Diversity Of Aflatoxin-Producing Aspergillus Flavus Isolated From Selected Groundnut Growing Agro-Ecological Zones Of Uganda, Amos Acur, Renee Arias, Steven Odongo, Samuel Tuhaise, National Agricultural Research Laboratories, Kampala, Uganda, John Adriko, Dennis Muhanguzi, Stephen Buah, Andrew Kiggundu

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Background: Groundnut pre- and post-harvest contamination is commonly caused by fungi from the Genus Aspergillus. Aspergillus flavus is the most important of these fungi. It belongs to section Flavi; a group consisting of aflatoxigenic (A. flavus, A. parasiticus and A. nomius) and non-aflatoxigenic (A. oryzae, A. sojae and A. tamarii) fungi. Aflatoxins are food-borne toxic secondary metabolites of Aspergillus species associated with severe hepatic carcinoma and children stuntedness. Despite the well-known public health significance of aflatoxicosis, there is a paucity of information about the prevalence, genetic diversity and population structure of A. flavus in different …

Genetic Diversity Among Mycobacterium Avium Subspecies Revealed By Analysis Of Complete Genome Sequences, John Bannantine, Cyril Conde, Darrell O. Bayles, Maxime Branger, Franck Biet

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Mycobacterium avium comprises four subspecies that contain both human and veterinary pathogens. At the inception of this study, twenty-eight M. avium genomes had been annotated as RefSeq genomes, facilitating direct comparisons. These genomes represent strains from around the world and provided a unique opportunity to examine genome dynamics in this species. Each genome was confirmed to be classified correctly based on SNP genotyping, nucleotide identity and presence/absence of repetitive elements or other typing methods. The Mycobacterium avium subspeciesparatuberculosis (Map) genome size and organization was remarkably consistent, averaging 4.8 Mb with a variance of only 29.6 kb among the 13 strains. …

Comparison Of Sheep, Goats, And Calves As Infection Models For Mycobacterium Avium Subsp. Paratuberculosis, Judith R. Stabel, J. P. Bannantine, Jesse M. Hostetter

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Animal infection models to study Mycobacterium avium subsp. paratuberculosis (MAP) infection are useful for evaluating the efficacy of vaccines and other therapeutics for the prevention or treatment of infection. The goal of the present study was to compare smaller ruminants, sheep and goats, with calves as infection models. Neonatal sheep, goats, and calves (n = 4) received 109 cfu of a cattle isolate of MAP in milk replacer on days 0, 3 and 6 in a 12-month study and sampled monthly thereafter. Results demonstrated a robust antigen-specific IFN-γ response at 90 days post-inoculation for sheep and goats, with lower responses …

Forage Breeding. From Forages: The Science Of Grassland Agriculture, Volume Ii, Michael D. Casler, Kenneth P. Vogel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Plant breeding is human-directed evolution.This process has been used to develop all major crops and their respective races, strains, or cultivars. Although humans have successfully manipulated the genetic resources of plants for several thousand years, the science of genetics and breeding was not developed until the twentieth century. Breeding work on a few forage crops began in the early part of the twentieth century (Wilkins and Humphreys 2003). Initial work was focused on developing strains that had improved establishment, persistence, high forage yields, and good insect and disease resistance. These remain essential attributes of cultivated forages (Burton 1986). Since the …

Forage Systems For The Temperate Subhumid And Semiarid Areas, John R. Hendrickson, Corey Moffet

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

No abstract provided.

Deciphering The Past To Inform The Future: Preparing For The Next (“Really Big”) Extreme Event, Debra Pc Peters, N Dylan Burruss, Gregory S. Okin, Jerry L. Hatfield, Stacey Lp Scroggs, Haitao Huang, Colby W. Brungard, Jin Yao

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Climate change will bring more extremes in temperature and precipitation that will impact productivity and ecosystem resilience throughout agroecosystems worldwide. Historical events can be used to identify drivers that impact future events. A catastrophic drought in the US in the 1930s resulted in an abrupt boundary between areas severely impacted by the Dust Bowl and areas that were less severely affected. Historical primary production data confirmed the location of this boundary at the border between two states (Nebraska and Iowa). Local drivers of weather and soils explained production responses across the boundary before and after the drought (1926–1948). During the …

Seed Production, Jeffrey J. Steiner, Tim L. Springer

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

No abstract provided.

Simultaneous Cognate Epitope Recognition By Bovine Cd4 And Cd8 T Cells Is Essential For Primary Expansion Of Antigen-Specific Cytotoxic T-Cells Following Ex Vivo Stimulation With A Candidate Mycobacterium Avium Subsp. Paratuberculosis Peptide Vaccine, Gaber S. Abdellrazeq, Lindsay M. Fry, Mahmoud M. Elnaggar, J. P. Bannantine, David A. Schneider, William M. Chamberlin, Asmaa H.A. Mahmoud, Kun-Taek Park, Victoria Hulubei, William C. Davis

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Studies in cattle show CD8 cytotoxic T cells (CTL), with the ability to kill intracellular bacteria, develop following stimulation of monocyte-depleted peripheral blood mononuclear cells (mdPBMC) with antigen-presenting cells (APC, i.e. conventional dendritic cells [cDC] and monocyte-derived DC [MoDC]) pulsed with MMP, a membrane protein from Mycobacterium avium subsp. paratuberculosis (Map) encoded byMAP2121c. CTL activity was diminished if CD4 T cells were depleted from mdPBMC before antigen (Ag) presentation by APC, suggesting simultaneous cognate recognition of MMP epitopes presented by MHC I and MHC II molecules to CD4 and CD8 T cells is essential for development of CTL activity. To …

Induction Of Seed Coat Darkening In Common Beans (Phaseolus Vulgaris L.) And The Association With Cooking Time After Storage, Renata C. Alvares, Helton S. Pereira, Leonardo C. Melo, Phillip N. Miklas, Patrícia G.S. Melo

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Carioca is the most important edible dry bean (Phaseolus vulgaris L.) grown in Brazil. It represents the largest dry bean market class in the world. The seed coat of carioca beans will darken under adverse harvest conditions and with the increasing of storage time. In general, darkened seeds are associated with older seeds that suffer from prolonged cooking times. A relatively new ‘slow darkening’ trait is available in carioca that delays seed coat darkening under storage. However, its effect on cooking time is unknown. The objective of this work was to evaluate two induction methods of seed coat darkening and …

Contributions In Puerto Rico To Bean, Phaseolus Spp., Research, James S. Beaver, Consuelo Estévez De Jensen, Phillip N. Miklas, Timothy G. Porch

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Most literature reviews focus on a specific topic. The purpose of this paper, however, is to review the contributions made by a multidisciplinary team of researchers at a specific location (Puerto Rico) over a period of several decades. This paper documents bean research of the University of Puerto Rico and the USDA-ARS Tropical Agriculture Research Station during the past century. The following illustrates the merits of continuity of effort in research and shows that research often follows a logical sequence of actions to solve problems related to genetic improvement as well as to study biotic and abiotic factors that affect …

Aphid-Responsive Defense Networks In Hybrid Switchgrass, Kyle Koch, Nathan A. Palmer, Teresa Donze-Reiner, Erin D. Scully, Javier Seravalli, Keenan Amundsen, Paul Twigg, Joe Louis, Jeffery D. Bradshaw, Tiffany Heng-Moss, Gautam Sarath

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Aphid herbivory elicits plant defense-related networks that are influenced by host genetics. Plants of the upland switchgrass (Panicum virgatum) cultivar Summer can be a suitable host for greenbug aphids (Schizaphis graminum; GB), and yellow sugarcane aphids (Sipha flava, YSA), whereas the lowland cultivar Kanlow exhibited multi-species resistance that curtails aphid reproduction. However, stabilized hybrids of Summer (♀) x Kanlow (♂) (SxK) with improved agronomics can be damaged by both aphids. Here, hormone and metabolite analyses, coupled with RNA-Seq analysis of plant transcriptomes, were utilized to delineate defense networks induced by aphid feeding in SxK switchgrass and pinpoint plant transcription factors …

Role Of Inherent Soil Characteristics In Assessing Soil Health Across Missouri, Stacy M. Zuber, Kristen S. Veum, Robert L. Myers, Newell R. Kitchen, Stephen H. Anderson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Soil health indicator values vary based on parent material, native vegetation, and other soil forming factors; therefore, useful interpretations require consideration of inherent soil characteristics. Our objective was to evaluate the distribution of soil health indicators across soil and climate gradients throughout the state of Missouri through a statewide cover crop cost-share program. Soil samples (0–7 cm) were collected from 5,300 agricultural fields and analyzed for several soil health indicators. Comparisons were made among six regions in the state based on Major Land Resource Area and county boundaries. Results varied for soil organic carbon (C), active C, potentially mineralizable nitrogen, …