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Full-Text Articles in Life Sciences

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 ...


Identification Of Quantitative Trait Loci For Leaf-Related Traits In An Ibm Syn10 Dh Maize Population Across Three Environments, Langlang Ma, Zhongrong Guan, Zhiteng Zhang, Xiaoxiang Zhang, Yanling Zhang, Chaoying Zou, Huanwei Peng, Guangtang Pan, Michael Lee, Yaou Shen, Thomas Lubberstedt Feb 2018

Identification Of Quantitative Trait Loci For Leaf-Related Traits In An Ibm Syn10 Dh Maize Population Across Three Environments, Langlang Ma, Zhongrong Guan, Zhiteng Zhang, Xiaoxiang Zhang, Yanling Zhang, Chaoying Zou, Huanwei Peng, Guangtang Pan, Michael Lee, Yaou Shen, Thomas Lubberstedt

Agronomy Publications

Leaf-related traits (leaf length, leaf width, leaf area and leaf angle) are very important for the yield of maize (Zea mays L) due to their influence on plant type. Therefore, it is necessary to identify quantitative trait loci (QTLs) for leaf-related traits. In this report, 221 doubled haploid lines (DHLs) of an IBM Syn10 DH population were provided for QTL mapping. In total, 54 QTLs were detected for leaf-related traits in single environments using a high-density genetic linkage map. Among them, only eight common QTLs were identified across two or three environments, and the common QTLs for the four traits ...


Extent Of Pollen-Mediated Gene Flow And Seed Longevity In Switchgrass (Panicum Virgatum L.): Implications For Biosafety Procedures, Hsiaochi Chang, Allison A. Snow, Evans Mutegi, Emily M. Lewis, Emily A. Heaton, Maria N. Miriti Feb 2018

Extent Of Pollen-Mediated Gene Flow And Seed Longevity In Switchgrass (Panicum Virgatum L.): Implications For Biosafety Procedures, Hsiaochi Chang, Allison A. Snow, Evans Mutegi, Emily M. Lewis, Emily A. Heaton, Maria N. Miriti

Agronomy Publications

New switchgrass (Panicum virgatum L.) bioenergy cultivars are being bred through genetic engineering; however, baseline information is urgently needed to establish guidelines for small scale field trials prior to commercialization. In this study, we documented the pattern of pollen mediated gene flow and the extent of seed longevity in field experiments. To mimic crop-to wild, pollen-mediated gene flow, we planted wild recipient switchgrass ramets at various distances away from cultivar donor ramets at two sites in Ohio. Percent hybridization at each distance was estimated from seed set on recipient ramets, which were self-incompatible clones. The pattern of gene flow was ...


Maize And Soybean Root Front Velocity And Maximum Depth In Iowa, Usa, Raziel A. Ordonez, Michael J. Castellano, Jerry L. Hatfield, Matthew J. Helmers, Mark A. Licht, Matthew Liebman, Ranae Dietzel, Rafael Martinez-Feria, Javed Iqbal, Laila A. Puntel, S. Carolina Cordova, Kaitlin Togliatti, Emily E. Wright, Sotirios V. Archontoulis Jan 2018

Maize And Soybean Root Front Velocity And Maximum Depth In Iowa, Usa, Raziel A. Ordonez, Michael J. Castellano, Jerry L. Hatfield, Matthew J. Helmers, Mark A. Licht, Matthew Liebman, Ranae Dietzel, Rafael Martinez-Feria, Javed Iqbal, Laila A. Puntel, S. Carolina Cordova, Kaitlin Togliatti, Emily E. Wright, Sotirios V. Archontoulis

Agronomy Publications

Quantitative measurements of root traits can improve our understanding of how crops respond to soil and weather conditions, but such data are rare. Our objective was to quantify maximum root depth and root front velocity (RFV) for maize (Zea mays) and soybean (Glycine max) crops across a range of growing conditions in the Midwest USA. Two sets of root measurements were taken every 10–15 days: in the crop row (in-row) and between two crop rows (center-row) across six Iowa sites having different management practices such as planting dates and drainage systems, totaling 20 replicated experimental treatments. Temporal root data ...


A Pectin Methylesterase Zmpme3 Is Expressed In Gametophyte Factor1-S (Ga1-S) Silks And Maps To That Locus In Maize (Zea Mays L.), Adrienne N. Moran Lauter, Michael G. Muszynski, Ryan D. Huffman, M. Paul Scott Nov 2017

A Pectin Methylesterase Zmpme3 Is Expressed In Gametophyte Factor1-S (Ga1-S) Silks And Maps To That Locus In Maize (Zea Mays L.), Adrienne N. Moran Lauter, Michael G. Muszynski, Ryan D. Huffman, M. Paul Scott

Agronomy Publications

The ga1 locus of maize confers unilateral cross incompatibility, preventing cross pollination between females carrying the incompatible Ga1-s allele and males not carrying a corresponding compatible allele. To characterize this system at the molecular level, we carried out a transcript profiling experiment in which silks from near isogenic lines carrying the Ga1-sand ga1 alleles were compared. While several differentially expressed genes were identified, only one mapped to the known location of ga1. This gene is a pectin methylesterase (PME), which we designated as ZmPme3, and is present and expressed only in Ga1-s genotypes. While a functional ZmPME3 is ...


Chlorophyll Can Be Reduced In Crop Canopies With Little Penalty To Photosynthesis, Berkley J. Walker, Darren T. Drewry, Rebecca A. Slattery, Andy Vanloocke, Young B. Cho, Donald R. Ort Oct 2017

Chlorophyll Can Be Reduced In Crop Canopies With Little Penalty To Photosynthesis, Berkley J. Walker, Darren T. Drewry, Rebecca A. Slattery, Andy Vanloocke, Young B. Cho, Donald R. Ort

Agronomy Publications

The hypothesis that reducing chlorophyll content (Chl) can increase canopy photosynthesis in soybeans was tested using an advanced model of canopy photosynthesis. The relationship between leaf Chl, leaf optical properties, and photosynthetic biochemical capacity were measured in 67 soybean accessions showing large variation in leaf Chl. These relationships were integrated into a biophysical model of canopy-scale photosynthesis to simulate the intercanopy light environment and carbon assimilation capacity of canopies with WT, a Chl-deficient mutant (Y11y11), and 67 other mutants spanning the extremes of Chl to quantify the impact of variation in leaf-level Chl on canopy-scale photosynthetic assimilation and identify possible ...


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 ...


How Fast Do Soybeans Dry Down During The Preharvest Time?, Rafael A. Martinez-Feria, Sotirios Archontoulis, Mark Licht Sep 2017

How Fast Do Soybeans Dry Down During The Preharvest Time?, Rafael A. Martinez-Feria, Sotirios Archontoulis, Mark Licht

Agronomy Publications

Soybean fields are nearing maturing across Iowa with minimal delay compared to 2016 due to cool temperatures. However, soybean sensitivity to day length speeds up crop development towards physiological maturity. During this time, senescence is occurring and carbohydrates are being converted to oils. Soybean seed moisture changes very little and remains near 60 percent during the de-greening period. As the pods turn to mature color at the beginning of maturity stage (R7), seed dry matter accumulation is complete and seed moisture rapidly decreases.


All Washed Out? Foliar Nutrient Resorption And Leaching In Senescing Switchgrass, Ruth H. Burke, Kenneth J. Moore, Martin J. Shipitalo, F. E. Miguez, Emily A. Heaton Jun 2017

All Washed Out? Foliar Nutrient Resorption And Leaching In Senescing Switchgrass, Ruth H. Burke, Kenneth J. Moore, Martin J. Shipitalo, F. E. Miguez, Emily A. Heaton

Agronomy Publications

Ideal bioenergy feedstocks are low in nutrients that act as anti-quality factors during conversion processes. Research has shown that delaying harvest of temperate perennial grasses until late winter reduces nutrient content, primarily due to end-season resorption, but also indicates a role for foliar nutrient leaching. While end-season resorption has been estimated, foliar nutrient leaching has not, and is a factor that could refine harvest recommendations. Additionally, establishing a baseline of mineral loss during switchgrass senescence will improve our understanding of leaf-level nutrient resorption. Therefore, we applied simulated rainfall to replicated (n = 5) plots within a previously established switchgrass stand to ...


Time Interval Between Cover Crop Termination And Planting Influences Corn Seedling Disease, Plant Growth, And Yield, J. Acharya, M. G. Bakker, T. B. Moorman, T. C. Kaspar, A. W. Lenssen, A. E. Robertson Apr 2017

Time Interval Between Cover Crop Termination And Planting Influences Corn Seedling Disease, Plant Growth, And Yield, J. Acharya, M. G. Bakker, T. B. Moorman, T. C. Kaspar, A. W. Lenssen, A. E. Robertson

Agronomy Publications

Experiments were established in a controlled-growth chamber and in the field to evaluate the effect of the length of time intervals between winter rye cover crop termination and corn planting on corn seedling disease, corn growth, and grain yield in 2014 and 2015. Rye termination dates ranged from 25 days before planting (DBP) to 2 days after planting (DAP) corn in the field and from 21 DBP to 1 DAP in controlled studies. Results were similar in both environments. In general, shorter intervals increased seedling disease and reduced corn emergence, shoot growth, and grain yield of corn following winter rye ...


Photosynthesis, Light Use Efficiency, And Yield Of Reduced-Chlorophyll Soybean Mutants In Field Conditions, Rebecca A. Slattery, Andy Vanloocke, Carl J. Bernacchi, Xin-Guang Zhu, Donald R. Ort Apr 2017

Photosynthesis, Light Use Efficiency, And Yield Of Reduced-Chlorophyll Soybean Mutants In Field Conditions, Rebecca A. Slattery, Andy Vanloocke, Carl J. Bernacchi, Xin-Guang Zhu, Donald R. Ort

Agronomy Publications

Reducing chlorophyll (chl) content may improve the conversion efficiency of absorbed photosynthetically active radiation into biomass and therefore yield in dense monoculture crops by improving light penetration and distribution within the canopy. The effects of reduced chl on leaf and canopy photosynthesis and photosynthetic efficiency were studied in two reportedly robust reduced-chl soybean mutants, Y11y11 and y9y9, in comparison to the wild-type (WT) “Clark” cultivar. Both mutants were characterized during the 2012 growing season whereas only the Y11y11 mutant was characterized during the 2013 growing season. Chl deficiency led to greater rates of leaf-level photosynthesis per absorbed photon early in ...


Main And Epistatic Loci Studies In Soybean For Sclerotinia Sclerotiorum Resistance Reveal Multiple Modes Of Resistance In Multi-Environments, Tara C. Moellers, Arti Singh, Jiaoping Zhang, Jae Brungardt, Mehdi Kabbage, Daren S. Mueller, Craig R. Grau, Ashish Ranjan, Damon L. Smith, R. V. Chowdy-Reddy, Asheesh K. Singh Jan 2017

Main And Epistatic Loci Studies In Soybean For Sclerotinia Sclerotiorum Resistance Reveal Multiple Modes Of Resistance In Multi-Environments, Tara C. Moellers, Arti Singh, Jiaoping Zhang, Jae Brungardt, Mehdi Kabbage, Daren S. Mueller, Craig R. Grau, Ashish Ranjan, Damon L. Smith, R. V. Chowdy-Reddy, Asheesh K. Singh

Agronomy Publications

Genome-wide association (GWAS) and epistatic (GWES) studies along with expression studies in soybean [Glycine max (L.) Merr.] were leveraged to dissect the genetics of Sclerotinia stem rot (SSR) [caused by Sclerotinia sclerotiorum (Lib.) de Bary], a significant fungal disease causing yield and quality losses. A large association panel of 466 diverse plant introduction accessions were phenotyped in multiple field and controlled environments to: (1) discover sources of resistance, (2) identify SNPs associated with resistance, and (3) determine putative candidate genes to elucidate the mode of resistance. We report 58 significant main effect loci and 24 significant epistatic interactions associated with ...


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.


Genetic Mapping Of Qtl For Maize Leaf Width Combining Ril And If2 Populations, Ruixiang Liu, Qingchang Meng, Fei Zhang, Lingjie Kong, Jianhua Yuan, Thomas Lubberstedt Jan 2017

Genetic Mapping Of Qtl For Maize Leaf Width Combining Ril And If2 Populations, Ruixiang Liu, Qingchang Meng, Fei Zhang, Lingjie Kong, Jianhua Yuan, Thomas Lubberstedt

Agronomy Publications

Leaf width is an important component of plant architecture that affects light capture during photosynthesis and wind circulation under dense planting conditions. To improve understanding of the genetic mechanisms involved in leaf width at different positions, a comprehensive evaluation using the RIL (Recombinant Inbred Line) and IF2 (Immortalized F2) populations and a subsequent meta-analysis were performed. Forty-seven QTL associated with leaf width at different positions below the tassel were detected. The individual effects of QTL explained 3.5% to 17.0% of the observed phenotypic variation, and ten QTL explained over 10%. The initial QTL were integrated into eight mQTL ...


Soil Total Carbon And Crop Yield Affected By Crop Rotation And Cultural Practice, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, William B. Stevens, Jalal D. Jabro Jan 2017

Soil Total Carbon And Crop Yield Affected By Crop Rotation And Cultural Practice, Upendra M. Sainju, Andrew W. Lenssen, Brett L. Allen, William B. Stevens, Jalal D. Jabro

Agronomy Publications

Stacked crop rotations and improved cultural practices have been used to control pests, but their impact on soil total carbon (STC) (soil organic carbon [SOC] + soil inorganic carbon [SIC]) and crop yield are lacking. We evaluated the effects of stacked vs. alternate-year rotations and cultural practices on STC at the 0- to 125-cm depth and annualized crop yields from 2005 to 2011 in the northern Great Plains. Stacked rotations were durum (Triticum turgidum L.)–durum–canola (Brassica napus L.)–pea (Pisum sativum L.) (D–D–C–P) and durum–durum–flax (Linum usitatissimum L.)–pea (D–D–F–P). Alternate-year ...


Tanscriptomic Study Of The Soybean-Fusarium Virguliforme Interaction Revealed A Novel Ankyrin-Repeat Containing Defense Gene, Expression Of Whose During Infection Led To Enhanced Resistance To The Fungal Pathogen In Transgenic Soybean Plants, Micheline N. Ngaki, Bing Wang, Binod B. Sahu, Subodh K. Srivastava, Mohammad S. Farooqi, Sekhar Kambakam, Sivakumar Swaminathan, Madan K. Bhattacharyya Oct 2016

Tanscriptomic Study Of The Soybean-Fusarium Virguliforme Interaction Revealed A Novel Ankyrin-Repeat Containing Defense Gene, Expression Of Whose During Infection Led To Enhanced Resistance To The Fungal Pathogen In Transgenic Soybean Plants, Micheline N. Ngaki, Bing Wang, Binod B. Sahu, Subodh K. Srivastava, Mohammad S. Farooqi, Sekhar Kambakam, Sivakumar Swaminathan, Madan K. Bhattacharyya

Agronomy Publications

Fusarium virguliforme causes the serious disease sudden death syndrome (SDS) in soybean. Host resistance to this pathogen is partial and is encoded by a large number of quantitative trait loci, each conditioning small effects. Breeding SDS resistance is therefore challenging and identification of single-gene encoded novel resistance mechanisms is becoming a priority to fight this devastating this fungal pathogen. In this transcriptomic study we identified a few putative soybean defense genes, expression of which is suppressed during F. virguliformeinfection. The F. virguliforme infection-suppressed genes were broadly classified into four major classes. The steady state transcript levels of many of ...


Delayed Senescence In Soybean: Terminology, Research Update, And Survey Results From Growers, C. J. Harbach, T. W. Allen, C. R. Bowen, J. A. Davis, C. B. Hill, M. Leitman, B. R. Leonard, D. S. Mueller, G. B. Padgett, X. A. Phillips, R. W. Schneider, E. J. Sikora, A. K. Singh, G. L. Hartman Apr 2016

Delayed Senescence In Soybean: Terminology, Research Update, And Survey Results From Growers, C. J. Harbach, T. W. Allen, C. R. Bowen, J. A. Davis, C. B. Hill, M. Leitman, B. R. Leonard, D. S. Mueller, G. B. Padgett, X. A. Phillips, R. W. Schneider, E. J. Sikora, A. K. Singh, G. L. Hartman

Agronomy Publications

The terms used to describe symptoms of delayed senescence in soybean often are used inconsistently or interchangeably and do not adequately distinguish the observed symptoms in the field. Various causes have been proposed to explain the development of delayed senescence symptoms. In this article, we review published reports on delayed senescence symptoms in soybean, summarize current research findings, provide examples of terms related to specific symptoms, and present an overview of the results of a multi-state survey directed to soybean growers to understand their concerns about delayed soybean senescence. Some of these terms, such as green bean syndrome and green ...


Identifying New Sources Of Resistance To Brown Stem Rot In Soybean, Chantal E. Mccabe, Asheesh K. Singh, Leonor F. Leandro, Silvia R. Cianzio, Michelle A. Graham Jan 2016

Identifying New Sources Of Resistance To Brown Stem Rot In Soybean, Chantal E. Mccabe, Asheesh K. Singh, Leonor F. Leandro, Silvia R. Cianzio, Michelle A. Graham

Agronomy Publications

Brown stem rot (BSR), caused by the fungus Phialophora gregata f. sp. sojae (Allington & D.W. Chamberlain) W. Gams (syn. Cadophora gregata), causes yield losses up to 38%. Three dominant BSR-resistant genes have been identified: Rbs1, Rbs2, and Rbs3. Additional BSR resistance loci will complement breeding efforts by expanding the soybean [Glycine max (L.) Merr.] genetic base. The objective of this research was to determine if PI 594637, PI 594638B, PI 594650A, and PI 594858B contained novel BSR resistance genes. The accessions were crossed to three genotypes with known BSR resistance genes and populations were developed for allelism studies. A ...


Diversity Of Maize Shoot Apical Meristem Architecture And Its Relationship To Plant Morphology, Addie M. Thompson, Jianming Yu, Marja C. P. Timmermans, Patrick S. Schnable, James E. Crants, Michael J. Scanlon, Gary J. Muehlbauer May 2015

Diversity Of Maize Shoot Apical Meristem Architecture And Its Relationship To Plant Morphology, Addie M. Thompson, Jianming Yu, Marja C. P. Timmermans, Patrick S. Schnable, James E. Crants, Michael J. Scanlon, Gary J. Muehlbauer

Agronomy Publications

The shoot apical meristem contains a pool of undifferentiated stem cells and controls initiation of all aerial plant organs. In maize (Zea mays), leaves are formed throughout vegetative development; on transition to floral development, the shoot meristem forms the tassel. Due to the regulated balance between stem cell maintenance and organogenesis, the structure and morphology of the shoot meristem are constrained during vegetative development. Previous work identified loci controlling meristem architecture in a recombinant inbred line population. The study presented here expanded on this by investigating shoot apical meristem morphology across a diverse set of maize inbred lines. Crosses of ...


Allmaps: Robust Scaffold Ordering Based On Multiple Maps, Haibao Tang, Xingtan Zhang, Chenyong Miao, Jisen Zhang, Ray Ming, James C. Schnable, Patrick S. Schnable, Eric Lyons, Jianguo Lu Jan 2015

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

Agronomy 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 ...


Integrating Sheep Grazing Into Cereal-Based Crop Rotations: Spring Wheat Yields And Weed Communities, Zach J. Miller, Fabian D. Menalled, Upendra M. Sainju, Andrew W. Lenssen, Patrick G. Hatfield Jan 2015

Integrating Sheep Grazing Into Cereal-Based Crop Rotations: Spring Wheat Yields And Weed Communities, Zach J. Miller, Fabian D. Menalled, Upendra M. Sainju, Andrew W. Lenssen, Patrick G. Hatfield

Agronomy Publications

Crop diversification and integration of livestock into cropping systems may improve the economic and environmental sustainability of agricultural systems. However, few studies have examined the integration of these practices in the semiarid areas of the Northern Great Plains (NGP). A 3-yr experiment was conducted near Bozeman, MT, to compare the effects of crop rotation diversity and weed management practices imposed during fallow periods [sheep (Ovis aries) grazing, reduced tillage, and conventional tillage] on spring wheat (Triticum aestivum L.) yields and weed pressure. Management treatments were applied to replicated whole plots, within which the split-plots received crop rotation treatments [continuous spring ...


Management And Tillage Infl Uence Barley Forage Productivity And Water Use In Dryland Cropping Systems, Andrew W. Lenssen, U. M. Sainju, J. D. Jabro, B. L. Allen, R. G. Evans Jan 2015

Management And Tillage Infl Uence Barley Forage Productivity And Water Use In Dryland Cropping Systems, Andrew W. Lenssen, U. M. Sainju, J. D. Jabro, B. L. Allen, R. G. Evans

Agronomy Publications

Annual cereal forages are resilient in water use (WU), water use efficiency (WUE), and weed control compared with grain crops in dryland systems. The combined influence of tillage and management systems on annual cereal forage productivity and WU is not well documented. We conducted a field study for the effects of tillage (no-till and tilled) and management (ecological and conventional) systems on WU and performance of forage barley (Hordeum vulgare L.) and weed biomass in two crop rotations (wheat [Triticum aestivum L.]–forage barley–pea [Pisum sativum L.] and wheat–forage barley–corn [Zea mays L.] –pea) from 2004 to ...


Autumnal Leaf Senescence In Miscanthus × Giganteus And Leaf [N] Differ By Stand Age, Nicholas N. Boersma, Frank G. Dohleman, Fernando E. Miguez, Emily A. Heaton Jan 2015

Autumnal Leaf Senescence In Miscanthus × Giganteus And Leaf [N] Differ By Stand Age, Nicholas N. Boersma, Frank G. Dohleman, Fernando E. Miguez, Emily A. Heaton

Agronomy Publications

Poor first winter survival in Miscanthus × giganteus has been anecdotally attributed to incomplete first autumn senescence, but these assessments never paired first-year with older M. × giganteus in side-by-side trials to separate the effect of weather from stand age. Here CO2 assimilation rate (A), photosystem II efficiency (ΦPSII), and leaf N concentration ([N]) were used to directly compare senescence in first, second, and third-year stands of M. ×giganteus. Three M. × giganteus fields were planted with eight plots, one field each in 2009, 2010, and 2011. To quantify autumnal leaf senescence of plants within each stand age, photosynthetic and leaf ...


Mapping A New Source Of Self-Fertility In Perennial Ryegrass (Lolium Perenne L.), Andrea Arias Aguirre, Bruno Studer, Javier Do Canto, Ursula Frei, Thomas Lubberstedt Dec 2013

Mapping A New Source Of Self-Fertility In Perennial Ryegrass (Lolium Perenne L.), Andrea Arias Aguirre, Bruno Studer, Javier Do Canto, Ursula Frei, Thomas Lubberstedt

Agronomy Publications

There is a rising interest of moving towards hybrid breeding in outcrossing species. Self-compatibility (SC), which occurs at low rates in self-incompatible species, could be used to develop inbred lines, a key requirement for hybrid breeding programs. In perennial ryegrass, the existence of SC independent from the self-incompatibility (SI) loci S and Z has been reported. In this study, we used 98 F2 individuals from a cross between a self-compatible ecotype and an individual of the VrnA mapping population that were tested with markers for two candidate linkage groups 3 and 5 as well as markers for candidate regions ...


Accelerating Plant Breeding, Gerald N. De La Fuente, Ursula K. Frei, Thomas Lubberstedt Dec 2013

Accelerating Plant Breeding, Gerald N. De La Fuente, Ursula K. Frei, Thomas Lubberstedt

Agronomy Publications

The growing demand for food with limited arable land available necessitates that the yield of major food crops continues to increase over time. Advances in marker technology, predictive statistics, and breeding methodology have allowed for continued increases in crop performance through genetic improvement. However, one major bottleneck is the generation time of plants, which is biologically limited and has not been improved since the introduction of doubled haploid technology. In this opinion article, we propose to implement in vitro nurseries, which could substantially shorten generation time through rapid cycles of meiosis and mitosis. This could prove a useful tool for ...


Phosphorus And Potassium Fertilization Effects On Soybean Seed Quality And Composition, Keaton Krueger, A. Susana Goggi, Antonio P. Mallarino, Russell E. Mullen Mar 2013

Phosphorus And Potassium Fertilization Effects On Soybean Seed Quality And Composition, Keaton Krueger, A. Susana Goggi, Antonio P. Mallarino, Russell E. Mullen

Agronomy Publications

The effects of P and K fertilization on soybean [Glycine max (L.) Merr.] seed quality are unclear. Fertilization rates can have a positive effect on yield and composition in some growing locations and years but not in others. As the cost of soybean seed production increases, seed companies are interested in improving seed quality of soybeans possibly through increased soil fertilization. The objectives of this study were to determine the effect of different levels of P and K fertilization on soybean seed quality defined as seed viability, vigor, and seed composition. Seed samples were obtained from a long-term P and ...


Effects Of Storage Temperature And Relative Humidity On Viability And Vigor Of Treated Soybean Seeds, Gladys C. Y. Mbofung, A. Susana Goggi, Leonor F. S. Leandro, Richard E. Mullen Jan 2013

Effects Of Storage Temperature And Relative Humidity On Viability And Vigor Of Treated Soybean Seeds, Gladys C. Y. Mbofung, A. Susana Goggi, Leonor F. S. Leandro, Richard E. Mullen

Agronomy Publications

Seed treatments are applied to soybean (Glycine max L. Merrill) seeds to control early season diseases and insects. Unsold, treated soybean seed must be disposed in a different manner than untreated seed. To minimize treated seed disposal costs, it is necessary to improve seed storage. The objective of this study was to determine the best storage environments that would minimize deterioration of chemically treated soybean seed from different maturity groups and seed compositions. Twenty-four soybean varieties, different in lipid and protein contents, and from four maturity groups, were treated either with fungicide, a mixture of fungicide + insecticide, and untreated and ...


Csr2- Soil Productivity Rating For Cropland In Iowa, Usa, C. Lee Burras, Rachel K. Owen Jan 2012

Csr2- Soil Productivity Rating For Cropland In Iowa, Usa, C. Lee Burras, Rachel K. Owen

Agronomy Publications

The Iowa Corn Suitability Rating (CSR2) is a soil productivity rating system used primarily for taxation purposes on cropland in Iowa and is derived from its original version “CSR.” CSR2 was created using seven transparent parameters that allow for efficient calculation.


Overview Of Mollisols In The World: Distribution, Land Use And Management, Xiaobing Liu, C. Lee Burras, Yuri S. Kravchenko, Artigas Duran, Ted Huffman, Hector Morras, Guillermo Studdert, Xingyi Zhang, Richard M. Cruse, Xiaohui Yuan Jan 2012

Overview Of Mollisols In The World: Distribution, Land Use And Management, Xiaobing Liu, C. Lee Burras, Yuri S. Kravchenko, Artigas Duran, Ted Huffman, Hector Morras, Guillermo Studdert, Xingyi Zhang, Richard M. Cruse, Xiaohui Yuan

Agronomy Publications

Mollisols a.k.a., Black Soils or Prairie Soils make up about 916 million ha, which is 7% of the world’s ice-free land surface. Their distribution strongly correlates with native prairie ecosystems, but is not limited to them. They are most prevalent in the mid-latitudes of North America, Eurasia, and South America. In North America, they cover 200 million ha of the United States, more than 40 million ha of Canada and 50 million ha of Mexico. Across Eurasia they cover around 450 million ha, extending from the western 148 million ha in southern Russia and 34 million ha ...


Soil Carbon Dioxide (Co2) Efflux Of Two Shrubs In Response To Plant Density In The Northern Loess Plateau Of China, Wei Fu, Mingbin Huang, Ming,An Shao, Robert Horton Oct 2010

Soil Carbon Dioxide (Co2) Efflux Of Two Shrubs In Response To Plant Density In The Northern Loess Plateau Of China, Wei Fu, Mingbin Huang, Ming,An Shao, Robert Horton

Agronomy Publications

Although plant density should affect soil carbon dioxide (CO2) efflux and carbon cycling in semi-arid regions, the effects of plant density on soil CO2 efflux are not well known. This study was performed to investigate the responses of soil CO2 efflux of two dominant shrubs (Caragana korshinkii and Salix psammophila) to plant density in the northern Loess Plateau of China. Two plant density treatments, low and high, were included for C. korshinkii (average 20,000 plants ha-1 and average 66,667 plants ha-1) and S. psammophila (average 9,583 plants ha-1 and average 31,250 plants ha-1). Soil CO2 efflux ...