Life Sciences Commons^™

Virion Composition Of Wheat Streak Mosaic Virus (Wsmv) And Its Use As An Expression Vector, Sourav Pal

Department of Plant Pathology: Dissertations, Theses, and Student Research

Wheat (Triticum aestivum L.) is the principal cereal grown in the United States, whose production ranks third in the world. Bacterial leaf streak (BLS) disease caused by Xanthomonas translucens pv. undulosa (xtu) is an emerging threat to wheat production in the Great Plains region of the United States of America. In this study, we engineered sequences encoding several plant-based antimicrobial peptides (AMP) were engineered into the WSMV genome and examined their effect on BLS disease in wheat infected by WSMV harboring AMP sequences. Out of nine AMPs, wheat expressing Ace-AMP1, PDF13, TK-AMP-D1, and TK-AMP-D3 produced resistance against the …

Assessment Of Foam Decontamination In Tomato Washing Process, Basim M. Alohali

Dissertations and Doctoral Documents from University of Nebraska-Lincoln, 2023–

The work of the dissertation investigated the efficacy of foam-based decontamination treatments to enhance microbial safety in Roma tomatoes, specifically targeting natural microflora and Salmonella contamination. Growing concerns over foodborne illnesses linked to fresh tomatoes and the limitations of conventional decontamination techniques, such as organic matter built-up and limited microbial reduction, are addressed. The primary objectives were to characterize the physiochemical properties of foams formed using various concentrations of Tween 20 (T20) and sodium dodecyl sulfate (SDS) with and without the addition of sodium hypochlorite (NaOCl) and peracetic acid (PAA), compare the efficacy of foam and traditional dump tank (DT) …

Post-Translational Regulation Of A Bidomain Glycerol-3-Phosphate Dehydrogenase Catalyzing Glycerol Synthesis Under Salinity Stress In Chlamydomonas Reinhardtii, Itzela Cruz-Powell, Binita Subedi, Yeongho Kim, Daniela Morales-Sánchez, Heriberto D. Cerutti

Center for Plant Science Innovation: Faculty and Staff Publications

Core chlorophytes possess glycerol-3-phosphate dehydrogenases (GPDs) with an unusual bidomain structure, consisting of a glycerol-3-phosphate phosphatase (GPP) domain fused to canonical GPD domains. These plastid-localized enzymes have been implicated in stress responses, being required for the synthesis of glycerol under high salinity and triacylglycerols under nutrient deprivation. However, their regulation under varying environmental conditions is poorly understood. C. reinhardtii transgenic strains expressing constitutively bidomain GPD2 did not accumulate glycerol or triacylglycerols in the absence of any environmental stress. Although the glycerol contents of both wild type and transgenic strains increased significantly upon exposure to high salinity, cycloheximide, an inhibitor of …

Undergraduate Instruction In Plant Pathology: In-Class Group Activities Improve Teamwork Skills In Semester-Long Projects, Teddy Garcia-Aroca

UNL Faculty Course Portfolios

PLPT 210: Plant Pathogens and Disease is an introductory-level undergraduate course offered by the Department of Plant Pathology at University of Nebraska-Lincoln. The course covers the basic principles of plant pathology, fundamental aspects of pathogen biology, and common management strategies. The course is offered every spring, and the enrollment is ~40 students per semester. Most students enrolled in the course are sophomores, juniors, to a lesser extent seniors from the Agronomy and Horticulture majors, Plant and Landscapes Systems, and Environmental Sciences. The course consists of lectures and in-class activities, and students are evaluated through quizzes, individual and in-group homework assignments, …

Genomes Of Multicellular Algal Sisters To Land Plants Illuminate Signaling Network Evolution, Xuehuan Feng, Jinfang Zheng, Iker Irisarri, Huihui Yu, Bo Zheng, Zahin Ali, Sophie De Vries, Jean Keller, Janine M. R. Fürst-Jansen, Armin Dadras, Jaccoline M. S. Zegers, Tim P. Rieseberg, Amra Dhabalia Ashok, Tatyana Darienko, Maaike J. Bierenbroodspot, Lydia Gramzow, Romy Petroll, Fabian B. Haas, Noe Fernandez-Pozo, Orestis Nousias, Tang Li, Elisabeth Fitzek, W. Scott Grayburn, Nina Rittmeier, Charlotte Permann, Florian Rümpler, John M. Archibald, Günter Theißen, Jeffrey P. Mower, Maike Lorenz16, Henrik Buschmann, Klaus Von Schwartzenberg, Lori Boston, Richard D. Hayes, Chris Daum, Kerrie Barry, Igor V. Grigoriev, Xiyin Wang, Fay-Wei Li, Stefan A. Rensing, Julius Ben Ari, Noa Keren, Assaf Mosquna, Andreas Holzinger, Pierre-Marc Delaux, Chi Zhang, Jinling Huang, Marek Mutwil6,, Jan De Vries, Yanbin Yin

Center for Plant Science Innovation: Faculty and Staff Publications

Zygnematophyceae are the algal sisters of land plants. Here we sequenced four genomes of filamentous Zygnematophyceae, including chromosome-scale assemblies for three strains of Zygnema circumcarinatum. We inferred traits in the ancestor of Zygnematophyceae and land plants that might have ushered in the conquest of land by plants: expanded genes for signaling cascades, environmental response, and multicellular growth. Zygnematophyceae and land plants share all the major enzymes for cell wall synthesis and remodifications, and gene gains shaped this toolkit. Co-expression network analyses uncover gene cohorts that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular …

Up-Regulation Of Non-Photochemical Quenching Improves Water Use Efficiency And Reduces Whole-Plant Water Consumption Under Drought In Nicotiana Tabacum, Benjamin Turc, Seema Sahay, Jared Haupt, Talles De Oliveira Santos, Geng Bai, Katarzyna Glowacka

Center for Plant Science Innovation: Faculty and Staff Publications

Water supply limitations will likely impose increasing restrictions on future crop production, underlining a need for crops that use less water per mass of yield. Water use efficiency (WUE) therefore becomes a key consideration in developing resilient and productive crops. In this study, we hypothesized that it is possible to improve WUE under drought conditions via modulation of chloroplast signals for stomatal opening by up-regulation of non-photochemical quenching (NPQ). Nicotiana tabacum plants with strong overexpression of the PsbS gene encoding PHOTOSYSTEM II SUBUNIT S, a key protein in NPQ, were grown under differing levels of drought. The PsbS-overexpressing lines lost …

The Emerging Role Of Non-Coding Rnas (Ncrnas) In Plant Growth, Development, And Stress Response Signaling, Amit Yadav, Jyotirmaya Mathan, Arvind Kumar Dubey, Anuradha Singh

Center for Plant Science Innovation: Faculty and Staff Publications

Plant species utilize a variety of regulatory mechanisms to ensure sustainable productivity. Within this intricate framework, numerous non-coding RNAs (ncRNAs) play a crucial regulatory role in plant biology, surpassing the essential functions of RNA molecules as messengers, ribosomal, and transfer RNAs. ncRNAs represent an emerging class of regulators, operating directly in the form of small interfering RNAs (siRNAs), microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs). These ncRNAs exert control at various levels, including transcription, posttranscription, translation, and epigenetic. Furthermore, they interact with each other, contributing to a variety of biological processes and mechanisms associated with stress resilience. …

Mycorrhizal Feedbacks Influence Global Forest Structure And Diversity, Camille S. Delavaux, Joseph A. Lamanna, Jonathan A. Myers, Richard P. Phillips, Salomón Aguilar, David Allen, Alfonso Alonso, Kristina J. Anderson-Teixeira, Matthew E. Baker, Jennifer L. Baltzer, Pulchérie Bissiengou, Mariana Bonfim, Norman A. Bourg, Warren Y. Brockelman, David F.R.P. Burslem, Li Wan Chang, Yang Chen, Jyh Min Chiang, Chengjin Chu, Keith Clay, Susan Cordell, Mary Cortese, Jan Den Ouden, Christopher Dick, Sisira Ediriweera, Erle C. Ellis, Anna Feistner, Amy L. Freestone, Thomas Giambelluca, Christian P. Giardina, Gregory S. Gilbert, Fangliang He, Jan Holík, Robert W. Howe, Walter Huaraca Huasca, Stephen P. Hubbell, Faith Inman, Patrick A. Jansen, Daniel J. Johnson, Kamil Kral, Sabrina E. Russo, Et Al.

Center for Plant Science Innovation: Faculty and Staff Publications

One mechanism proposed to explain high species diversity in tropical systems is strong negative conspecific density dependence (CDD), which reduces recruitment of juveniles in proximity to conspecific adult plants. Although evidence shows that plant-specific soil pathogens can drive negative CDD, trees also form key mutualisms with mycorrhizal fungi, which may counteract these effects. Across 43 large-scale forest plots worldwide, we tested whether ectomycorrhizal tree species exhibit weaker negative CDD than arbuscular mycorrhizal tree species. We further tested for conmycorrhizal density dependence (CMDD) to test for benefit from shared mutualists. We found that the strength of CDD varies systematically with mycorrhizal …

A Global-Temporal Analysis On Phytophthora Sojae Resistance-Gene Efficacy, Austin G. Mccoy, Richard R. Belanger, Carl A. Bradley, Daniel G. Cerritos-Garcia, Vinicius C. Garnica, Loren Giesler, Pablo E. Grijalba, Eduardo Guillin, Maria A. Henriquez, Yong Min Kim, Dean K. Malvick, Rashelle L. Matthiesen, Santiago X. Mideros, Zachary A. Noel, Alison E. Robertson, Mitchell G. Roth, Clarice L. Schmidt, Damon L. Smith, Adam H. Sparks, Darcy E.P. Telenko, Vanessa Tremblay, Owen Wally, Martin I. Chilvers

Department of Plant Pathology: Faculty Publications

Plant disease resistance genes are widely used in agriculture to reduce disease outbreaks and epidemics and ensure global food security. In soybean, Rps (Resistance to Phytophthora sojae) genes are used to manage Phytophthora sojae, a major oomycete pathogen that causes Phytophthora stem and root rot (PRR) worldwide. This study aims to identify temporal changes in P. sojae pathotype complexity, diversity, and Rps gene efficacy. Pathotype data was collected from 5121 isolates of P. sojae, derived from 29 surveys conducted between 1990 and 2019 across the United States, Argentina, Canada, and China. This systematic review shows a loss of efficacy of …

Evaluation Of Vegetative Indices To Determine Canopy Ground Cover For Winter Survival And Hybrid Necrosis In Winter Wheat, Micheal Young

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

The benefit of unmanned aircraft systems and image processing methods in agronomic research across numerous crops has been well documented as has the importance of wheat, Triticum aestivum L., on the global food supply. Hence there is great interest in digital solutions applied to aspects of wheat breeding. A major trait of importance to winter wheat breeders in higher latitudes is winter survival, which can result in poor yield and performance if lines do not survive extreme cold. Scoring winter survival is most commonly based on visual score of 0% to 100% with the higher percentage conveying higher winter survival …

The Pseudomonas Syringae Pv. Tomato Dc3000 Effector Hopd1 Interferes With Cellular Dynamics Associated With The Function Of The Plant Immune Protein Atnhr2b, Luis Francisco Marín-Ponce, Catalina Rodríguez-Puerto, Perla Rocha-Loyola, Clemencia M. Rojas

Department of Plant Pathology: Faculty Publications

The plant pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes disease in tomato, in the model plant Arabidopsis thaliana, and conditionally in Nicotiana benthamiana. The pathogenicity of Pst DC3000 is mostly due to bacterial virulence proteins, known as effectors, that are translocated into the plant cytoplasm through the type III secretion system (T3SS). Bacterial type III secreted effectors (T3SEs) target plants physiological processes and suppress defense responses to enable and support bacterial proliferation. The Pst DC3000 T3SE HopD1 interferes with plant defense responses by targeting the transcription factor NTL9. This work shows that HopD1 also targets …

Janus , A Spliceosome-Associated Protein, Promotes Mirna Biogenesis In Arabidopsis, Mu Li, Huihui Yu, Bangjun Zhou, Lu Gan, Shengjun Li, Chi Zhang, Bin Yu

Center for Plant Science Innovation: Faculty and Staff Publications

MicroRNAs ( miRNAs ) are important regulators of genes expression. Their levels are precisely controlled through modulating the activity of the microprocesser complex ( MC ) . Here, we report that JANUS, a homology of the conserved U2 snRNP assembly factor in yeast and human, is required for miRNA accumulation. JANUS associates with MC components Dicer-like 1 ( DCL1 ) and SERRATE ( SE ) and directly binds the stem- loop of pri-miRNAs. In a hypomorphic janus mutant, the activity of DCL1, the numbers of MC, and the interaction of primary miRNA transcript ( pri-miRNAs ) with MC are reduced. …

Dynamic Reconfiguration Of Switchgrass Proteomes In Response To Rust (Puccinia Novopanici) Infection, Nathan A. Palmer, Sophie Alvarez, Michael J. Naldrett, Anthony Muhle, Gautam Sarath, Serge J. Edmé, Satyanarayana Tatineni, Robert B. Mitchell, Gary Yuen

Department of Plant Pathology: Faculty Publications

Switchgrass (Panicum virgatum L.) can be infected by the rust pathogen (Puccinia novopanici) and results in lowering biomass yields and quality. Label-free quantitative proteomics was conducted on leaf extracts harvested from non-infected and infected plants from a susceptible cultivar (Summer) at 7, 11, and 18 days after inoculation (DAI) to follow the progression of disease and evaluate any plant compensatory mechanisms to infection. Some pustules were evident at 7 DAI, and their numbers increased with time. However, fungal DNA loads did not appreciably change over the course of this experiment in the infected plants. In total, 3830 …

Overcoming Genetic Paucity Of Camelina Sativa: Possibilities For Interspecific Hybridization Conditioned By The Genus Evolution Pathway, Rostyslav Y. Blume, Ruslan Kalendar, Liang Guo, Edgar B. Cahoon, Yaroslav B. Blume

Center for Plant Science Innovation: Faculty and Staff Publications

Camelina or false flax (Camelina sativa) is an emerging oilseed crop and a feedstock for biofuel production. This species is believed to originate from Western Asian and Eastern European regions, where the center of diversity of the Camelina genus is located. Cultivated Camelina species arose via a series of polyploidization events, serving as bottlenecks narrowing genetic diversity of the species. The genetic paucity of C. sativa is foreseen as the most crucial limitation for successful breeding and improvement of this crop. A potential solution to this challenge could be gene introgression from Camelina wild species or from …

A Facile Agrobacterium‑Mediated Transformation Method For The Model Unicellular Green Algae Chlamydomonas Reinhardtii, Truyen N. Quach, Shirley J. Sato, Mark R. Behrens, Paul N. Black, Concetta C. Dirusso, Heriberto D. Cerutti, Tom Elmo Clemente

Center for Plant Science Innovation: Faculty and Staff Publications

A reliable and simple Agrobacterium-mediated transformation system for the unicellular green algae model organism Chlamydomonas reinhardtii has been developed. The protocol has been successfully employed with both neomycin phosphotransferase II (nptII) and the phleomycin resistance (bleI) genes coupled with the selective agents paromomycin and zeocin, respectively. A set of binary vectors were assembled that carry the selectable marker cassettes under control either of the Rbcs2 alone or fused to the HSP270A leader sequence, PsaD, or ß-tubulin2 promoters. The corresponding T-DNA elements also harbored a cassette with a codon-optimized version of yellow fluorescence protein (YFP) under …

Genetic Improvement Of Tocotrienol Content Enhances The Oxidative Stability Of Canola Oil, Min Deng, Hao Chen, Wei Zhang, Edgar B. Cahoon, Yongming Zhou, Chunyu Zhang

Center for Plant Science Innovation: Faculty and Staff Publications

Background: Tocotrienols and tocopherols, which are synthesized in plastids of plant cells with similar functionalities, comprise vitamin E to serve as a potent lipid-soluble antioxidant in plants. The synthesis of tocopherols involves the condensation of homogentisic acid (HGA) and phytyl diphosphate (PDP) under the catalysis of homogentisate phytyltransferase (HPT). Tocotrienol synthesis is initiated by the condensation of HGA and geranylgeranyl diphosphate (GGDP) mediated by homogentisate geranylgeranyl transferase (HGGT). As one of the most important oil crops, canola seed is regarded as an ideal plant to efficiently improve the production of vitamin E tocochromanols through genetic engineering approaches. However, only …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard A. Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

A Protein Kinase Coordinates Cycles Of Autophagy And Glutaminolysis In Invasive Hyphae Of The Fungus Magnaporthe Oryzae Within Rice Cells, Gang Li, Ziwen Gong, Nawaraj Dulal, Margarita Marroquin-Guzman, Raquel O. Rocha, Michael Richter, Richard Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae produces invasive hyphae in living rice cells during early infection, separated from the host cytoplasm by plantderived interfacial membranes. However, the mechanisms underpinning this intracellular biotrophic growth phase are poorly understood. Here, we show that the M. oryzae serine/threonine protein kinase Rim15 promotes biotrophic growth by coordinating cycles of autophagy and glutaminolysis in invasive hyphae. Alongside inducing autophagy, Rim15 phosphorylates NADdependent glutamate dehydrogenase, resulting in increased levels of α- ketoglutarate that reactivate target-of-rapamycin (TOR) kinase signaling, which inhibits autophagy. Deleting RIM15 attenuates invasive hyphal growth and triggers plant immunity; exogenous addition of α-ketoglutarate prevents these …

P3 And Nia-Pro Of Turnip Mosaic Virus Are Independent Elicitors Of Superinfection Exclusion, Haritha Nunna, Feng Qu, Satyanarayana Tatineni

Department of Plant Pathology: Faculty Publications

Superinfection exclusion (SIE) is an antagonistic interaction between identical or closely related viruses in host cells. Previous studies by us and others led to the hypothesis that SIE was elicited by one or more proteins encoded in the genomes of primary viruses. Here, we tested this hypothesis using Turnip mosaic virus (TuMV), a member of the genus Potyvirus of the family Potyviridae, with significant economic consequences. To this end, individual TuMV-encoded proteins were transiently expressed in the cells of Nicotiana benthamiana leaves, followed by challenging them with a modified TuMV expressing the green fluorescent protein (TuMV-GFP). Three days after …

P3 And Nia-Pro Of Turnip Mosaic Virus Are Independent Elicitors Of Superinfection Exclusion, Haritha Nunna, Feng Qu, Satyanarayana Tatineni

Department of Plant Pathology: Faculty Publications

Superinfection exclusion (SIE) is an antagonistic interaction between identical or closely related viruses in host cells. Previous studies by us and others led to the hypothesis that SIE was elicited by one or more proteins encoded in the genomes of primary viruses. Here, we tested this hypothesis using Turnip mosaic virus (TuMV), a member of the genus Potyvirus of the family Potyviridae, with significant economic consequences. To this end, individual TuMV-encoded proteins were transiently expressed in the cells of Nicotiana benthamiana leaves, followed by challenging them with a modified TuMV expressing the green fluorescent protein (TuMV-GFP). Three days after …

Exploring The Potential Of Heterosis To Improve Nitrogen Use Efficiency In Popcorn Plants, Talles De Oliveira Santos, Antônio Teixeira Do Amaral Junior, Rosimeire Barboza Bispo, Wallace De Paula Bernado, Bruna Rohem Simão, Valter Jário De Lima, Marta Simone Mendonça Freitas, Freddy Mora-Poblete, Roberto Dos Santos Trindade, Samuel Henrique Kamphorst, Weverton Pereira Rodrigues, Eliemar Campostrini, Flávia Nicácio Viana, Cosme Damião Cruz

Center for Plant Science Innovation: Faculty and Staff Publications

Nitrogen is crucial for plant growth and development, and improving nitrogen use efficiency (NUE) is a viable strategy for reducing dependence on nitrogen inputs and promoting sustainability. While the benefits of heterosis in corn are well known, the physiological mechanisms underlying this phenomenon in popcorn are less understood. We aimed to investigate the effects of heterosis on growth and physiological traits in four popcorn lines and their hybrids under two contrasting nitrogen conditions. We evaluated morpho-agronomic and physiological traits such as leaf pigments, the maximum photochemical efficiency of PSII, and leaf gas exchange. Components associated with NUE were also evaluated. …

Induction And Suppression Of Gene Silencing In Plants By Nonviral Microbes, Eric Parperides, Kaoutar El Mounadi, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Gene silencing is a conserved mechanism in eukaryotes that dynamically regulates gene expression. In plants, gene silencing is critical for development and for maintenance of genome integrity. Additionally, it is a critical component of antiviral defence in plants, nematodes, insects, and fungi. To overcome gene silencing, viruses encode effectors that suppress gene silencing. A growing body of evidence shows that gene silencing and suppression of silencing are also used by plants during their interaction with nonviral pathogens such as fungi, oomycetes, and bacteria. Plant–pathogen interactions involve trans-kingdom movement of small RNAs into the pathogens to alter the function of genes …

Induction And Suppression Of Gene Silencing In Plants By Nonviral Microbes, Eric Parperides, Kaoutar El Mounadi, Hernan Garcia Ruiz

Department of Plant Pathology: Faculty Publications

Gene silencing is a conserved mechanism in eukaryotes that dynamically regulates gene expression. In plants, gene silencing is critical for development and for maintenance of genome integrity. Additionally, it is a critical component of antiviral defence in plants, nematodes, insects, and fungi. To overcome gene silencing, viruses encode effectors that suppress gene silencing. A growing body of evidence shows that gene silencing and suppression of silencing are also used by plants during their interaction with nonviral pathogens such as fungi, oomycetes, and bacteria. Plant–pathogen interactions involve trans-kingdom movement of small RNAs into the pathogens to alter the function of genes …

Gene Expression Changes Linked To Phenylpropanoid-Based Resistance To Fusarium Head Blight Of Wheat, Shiv Singla

Department of Plant Pathology: Dissertations, Theses, and Student Research

Fusarium graminearum is a devastating pathogen of wheat that causes Fusarium head blight (FHB) and contaminates the grain with the mycotoxin deoxynivalenol (DON). Resistance to FHB is quantitative and it is important to identify additional genes conferring resistance against it. The goal of this thesis was to examine if the constitutive expression of two sorghum phenylpropanoid pathway genes, SbCCoAOMT (encoding caffeoyl-CoA O-methyltransferase) and SbC3’H (encoding p-coumarate 3-hydroxylase), in the moderately-susceptible spring wheat CB037 can provide Type-I and Type-II resistance to F. graminearum and determine the underlying mechanisms of the enhanced resistance. The constitutive expression lines (CCoAOMT413, CCoAOMT421, C3H112, …

Fusarium Species Structure In Nebraska Corn, Yuchu Ma

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Fusarium species are known to infect corn and cause significant yield losses and mycotoxin contamination worldwide. In this study, we investigated the diversity of Fusarium species infecting corn in Nebraska and their potential to produce fumonisins and trichothecenes. A total of 259 Fusarium isolates were collected from different corn tissues (ear, stalk, and root), revealing a significant association between the various Fusarium species complexes and different plant parts (p < 0.05). Fusarium incarnatum-equiseti species complex (FIESC) was the most widespread and abundant, followed by the Fusarium sambucinum (FSAMSC) and Fusarium fujikuroi species complexes (FFSC). In the subsequent analysis, we investigated the mycotoxin …

Protease Inhibitor Asp Enhances Freezing Tolerance By Inhibiting Protein Degradation In Kumquat, Hua Yang, Ke-Wei Qiao, Jin-Jing Teng, Jia-Bei Chen, Ying-Li Zhong, Li-Qun Rao, Xing-Yao Xiong, Huang Li

Center for Plant Science Innovation: Faculty and Staff Publications

Cold acclimation is a complex biological process leading to the development of freezing tolerance in plants. In this study, we demonstrated that cold-induced expression of protease inhibitor FmASP in a Citrus-relative species kumquat [Fortunella margarita (Lour.) Swingle] contributes to its freezing tolerance by minimizing protein degradation. Firstly, we found that only cold-acclimated kumquat plants, despite extensive leaf cellular damage during freezing, were able to resume their normal growth upon stress relief. To dissect the impact of cold acclimation on this anti-freezing performance, we conducted protein abundance assays and quantitative proteomic analysis of kumquat leaves subjected to cold acclimation …

Mechanism Of Sphingolipid Homeostasis Revealed By Structural Analysis Of Arabidopsis Spt-Orm1 Complex, Peng Liu, Tian Xie, Xinyue Wu, Gongshe Han, Sita D. Gupta, Zike Zhang, Jian Yue, Feitong Dong, Kenneth Gable, Somashekarappa Niranjanakumari, Wanyuan Li, Lin Wang, Wenchen Liu, Ruifeng Yao, Edgar B. Cahoon, Teresa M. Dunn, Xin Gong

Center for Plant Science Innovation: Faculty and Staff Publications

The serine palmitoyltransferase (SPT) complex catalyzes the first and rate-limiting step in sphingolipid biosynthesis in all eukaryotes. ORM/ORMDL proteins are negative regulators of SPT that respond to cellular sphingolipid levels. However, the molecular basis underlying ORM/ORMDL-dependent homeostatic regulation of SPT is not well understood.We determined the cryo–electron microscopy structure of Arabidopsis SPT-ORM1 complex, composed of LCB1, LCB2a, SPTssa, and ORM1, in an inhibited state. A ceramide molecule is sandwiched between ORM1 and LCB2a in the cytosolic membrane leaflet. Ceramide binding is critical for the ORM1-dependent SPT repression, and dihydroceramides and phytoceramides differentially affect this repression. A hybrid β sheet, formed …

A Role For Heritable Transcriptomic Variation In Maize Adaptation To Temperate Environments, Guangchao Sun, Huihui Yu, Peng Wang, Martha Lopez‑Guerrero, Ravi V. Mural, Olivier N. Mizero, Marcin Grzybowski, Baoxing Song, Karin V. Van Dijk, Daniel P. Schachtman, Chi Zhang, James C. Schnable

Center for Plant Science Innovation: Faculty and Staff Publications

Background: Transcription bridges genetic information and phenotypes. Here, we evaluated how changes in transcriptional regulation enable maize (Zea mays), a crop originally domesticated in the tropics, to adapt to temperate environments.

Result: We generated 572 unique RNA-seq datasets from the roots of 340 maize genotypes. Genes involved in core processes such as cell division, chromosome organization and cytoskeleton organization showed lower heritability of gene expression, while genes involved in anti-oxidation activity exhibited higher expression heritability. An expression genome-wide association study (eGWAS) identified 19,602 expression quantitative trait loci (eQTLs) associated with the expression of 11,444 genes. A GWAS …

Soybean GmSaul1, A Bona Fide U-Box E3 Ligase, Negatively Regulates Immunity Likely Through Repressing The Activation Of GmMpk3, Jun-Mei Li, Mei-Yan Ye, Chaofeng Wang, Xiao-Han Ma, Ni-Ni Wu, Chen-Li Zhong, Yanjun Zhang, Ninghui Cheng, Paul A. Nakata, Lirong Zeng, Jian-Zhong Liu

Center for Plant Science Innovation: Faculty and Staff Publications

E3 ubiquitin ligases play important roles in plant immunity, but their role in soybean has not been investigated previously. Here, we used Bean pod mottle virus (BPMV)-mediated virusinduced gene silencing (VIGS) to investigate the function of GmSAUL1 (Senescence-Associated E3 Ubiquitin Ligase 1) homologs in soybean. When two closely related SAUL1 homologs were silenced simultaneously, the soybean plants displayed autoimmune phenotypes, which were significantly alleviated by high temperature, suggesting that GmSAUL1a/1b might be guarded by an R protein. Interestingly, silencing GmSAUL1a/1b resulted in the decreased activation of GmMPK6, but increased activation of GmMPK3 in response to flg22, …