Plant Biology Commons^™

Contrasting Metabolism In Perenniating Structures Of Upland And Lowland Switchgrass Plants Late In The Growing Season, Nathan Palmer, Aaron J. Saathoff, Christian M. Tobias, Paul Twigg, Yuannan Xia, Kenneth P. Vogel, Soundararajan Madhavan, Scott E. Sattler, Gautam Sarath

Department of Agronomy and Horticulture: Faculty Publications

Background: Switchgrass (Panicum virgatum L.) is being developed as a bioenergy crop for many temperate regions of the world. One way to increase biomass yields is to move southern adapted lowland cultivars to more northern latitudes. However, many southerly adapted switchgrass germplasm can suffer significant winter kill in northerly climes.

Materials and Methods: Here, we have applied next-generation sequencing in combination with biochemical analyses to query the metabolism of crowns and rhizomes obtained from two contrasting switchgrass cultivars. Crowns and rhizomes from field-grown lowland (cv Kanlow) and upland (cv Summer) switchgrass cultivars were collected from three randomly selected post-flowering …

Bot Canker Pathogens Could Complicate The Management Of Phytophthora Black Pod Of Cocoa, Idowu Jaiyeola, Rufus J. Akinrinlola, Gbodope S. Ige, Oluwatimilehin O. Omoleye, Abiola Oyedele, Bayode J. Odunayo, Omotayo J. Emehin, Marcus O. Bello, Anthony O. Adesemoye

Department of Plant Pathology: Faculty Publications

Black pod is a major hindrance to cocoa production in Nigeria. It is caused by three different Phytophthora species with Phytophthora megakarya as the most important species in Nigeria and West African subregion. Phytophthora spp. may enhance infections by opportunistic pathogens such as members of the Botryosphaeriacea that cause branch and trunk cankers in many woody plants across the world. Botryosphaeriacea has not been reported in cocoa nor in any woody plants in Nigeria to our knowledge. In the cocoa belt of Nigeria, research and understanding on cocoa black pod and Phytophthora is limited partly because of delayed or no …

A Coordinated Effort To Manage Soybean Rust In North America: A Success Story In Soybean Disease Monitoring, E. J. Sikora, T. W. Allen, K. A. Wise, G. Bergstrom, C. A. Bradley, J. Bond, D. Brown-Rytlewski, M. Chilvers, J. Damicone, E. Dewolf, Ohio State University Dorrance, N. Dufault, P. Esker, T. R. Faske, L. Giesler, N. Goldberg, J. Golod, I. R. G. Gomez, C. Grau, A. Grybauskas, G. Franc, R. Hammerschmidt, G. L. Hartman, R. A. Henn, D. Hershman, C. Hollier, T. Isakeit, S. Isard, B. Jacobsen, D. Jardine, R. Kemerait, S. Koenning, M. Langham, D. Malvick, S. Markell, J. J. Marois, S. Monfort, D. S. Mueller, J. Mueller, R. Mulrooney, M. Newman, L. Osborne, G. B. Padgett, B. E. Ruden, J. Rupe, R. Schneider, H. Schwartz, G. Shaner, S. Singh, E. Stromberg, L. Sweets, A. Tenuta, S. Vaiciunas, X. B. Yang, H. Young-Kelly, J. Zidek

Department of Plant Pathology: Faculty Publications

Existing crop monitoring programs determine the incidence and distribution of plant diseases and pathogens and assess the damage caused within a crop production region. These programs have traditionally used observed or predicted disease and pathogen data and environmental information to prescribe management practices that minimize crop loss (3,69). Monitoring programs are especially important for crops with broad geographic distribution or for diseases that can cause rapid and great economic losses. Successful monitoring programs have been developed for several plant diseases, including downy mildew of cucurbits, Fusarium head blight of wheat, potato late blight, and rusts of cereal crops (13,36,51,80).

Grazing Method Effects On Forage Production, Utilization, And Animal Performance On Nebraska Sandhills Meadow, Miles D. Redden

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

Mob grazing using ultrahigh stocking densities is promoted as a tool to increase the health and productivity of grasslands by increasing nutrient cycling and soil organic matter. Mob grazing can be defined as a strategy in which area available to grazing animals is restricted to achieve stocking densities of 200,000 kg/ha or greater. Objectives were to determine herbage production, utilization, and cattle weight gains among ultrahigh stocking density grazing and more conventional grazing methods on a Sandhills subirrigated meadow. Treatments included two replications of each of the following: four-pasture rotational grazing with two occupations per pasture in an 80-day grazing …

Synthesis Of The Effect Of Fire On Lesser Prairie‐Chickens, Eric Thacker, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

In this synthesis, we reviewed the scientific literature pertaining to the effects of fire on lesser prairie‐chickens and their habitat. Overall, research is generally lacking that directly assesses relationships among fire, both as a regime and a discrete event, to its effect on lesser prairie‐chicken behavior and habitat value. Yet, research has quantified the effects of fire on vegetation throughout the distribution of the lesser prairie‐chicken, which has been linked to known metrics of habitat value and broad landscape‐level habitat requirements.

To summarize the literature, lesser prairie‐chickens require broad landscapes of fire‐dependent grass‐shrub vegetation. Changes in the eco‐evolutionary fire regime …

Stacking Of A Stearoyl-Acp Thioesterase With A Dual-Silenced Palmitoyl-Acp Thioesterase And Δ12 Fatty Acid Desaturase In Transgenic Soybean, Hyunwoo Park, George L. Graef, Yixiang Xu, Patrick Tenopir, Thomas E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Soybean (Glycine max (L.) Merr) is valued for both its protein and oil, whose seed is composed of 40% and 20% of each component, respectively. Given its high percentage of polyunsaturated fatty acids, linoleic acid and linolenic acid, soybean oil oxidative stability is relatively poor. Historically food processors have employed a partial hydrogenation process to soybean oil as a means to improve both the oxidative stability and functionality in end-use applications. However, the hydrogenation process leads to the formation of trans-fats, which are associated with negative cardiovascular health. As a means to circumvent the need for the hydrogenation process, genetic …

First Report Of The Root-Knot Nematode Meloidogyne Enterolobii Parasitizing Watermelon From Veracruz, Mexico, A. Ramírez-Suárez, L. Rosas-Hernández, S. Alcasio-Rangel, Guillermo Pérez Valenzuela, T. O. Powers

Department of Plant Pathology: Faculty Publications

In early April 2012, a sampling of watermelon crop Citrullus lanatus (Thunb.) Matsum & Nakai, 1916 cv. Sunsugar took place as part of the National System of Epidemiological Phytosanitary Surveillance (SINAVEF-MEX). This sampling was conducted at Riachuelos locality, Tecolutla, Veracruz, located at the geographic coordinates: 20.42008° N and 96.9627° W, within 50 meters of the Gulf of Mexico. Plants showed yellowing, stunting, and high levels of infection expressed by extensive galling on the roots. These symptoms were reproduced in the greenhouse on watermelon cv. Sunsugar. Egg masses were extracted to obtain juveniles (J2). Female necks and perineal patterns were mounted …

The C-Terminus Of Wheat Streak Mosaic Virus Coat Protein Is Involved In Differential Infection Of Wheat And Maize Through Host-Specific Long-Distance Transport, Satyanarayana Tatineni, Roy French

Department of Plant Pathology: Faculty Publications

Viral determinants and mechanisms involved in extension of host range of monocot-infecting viruses are poorly understood. Viral coat proteins (CP) serve many functions in almost every aspect of the virus life cycle. The role of the Cterminal region of Wheat streak mosaic virus (WSMV) CP in virus biology was examined by mutating six negatively charged aspartic acid residues at positions 216, 289, 290, 326, 333, and 334. All of these amino acid residues are dispensable for virion assembly, and aspartic acid residues at positions 216, 333, and 334 are expendable for normal infection of wheat and maize. However, mutants D …

First Report Of Curvularia Inaequalis And Bipolaris Spicifera Causing Leaf Blight Of Buffalograss In Nebraska, B. S. Amaradasa, K. Amundsen

Department of Agronomy and Horticulture: Faculty Publications

During the summer of 2011, foliar blight was observed on buffalograss (Buchloë dactyloides (Nutt.) Engelm.) lawns in Lincoln and Waverly, Nebraska. Disease symptoms were common when buffalograss was growing above 30°C and in drought conditions. Disease symptoms began as dark brown oblong leaf spots, followed by leaf tip dieback and eventual blighting of entire tillers. Leaf infections would progress into patches of thinning turf. Diseased leaf pieces were rinsed in distilled water and placed on 1.5% water agar. Two mitosporic fungal species having conidial morphology of Curvularia and Bipolaris were isolated. Colonies of Curvularia isolates grown on ¼× PDA …

Arabidopsis Accelerated Cell Death 11, Acd11, Is A Ceramide-1-Phosphate Transfer Protein And Intermediary Regulator Of Phytoceramide Levels, Dhirendra K. Simanshu, Xiuhong Zhai, David Munch, Daniel Hofius, Jennifer E. Markham, Jacek Bielawski, Alicja Bielawska, Lucy Malinina, Julian G. Molotkovsky, John W. Mundy, Dinshaw J. Patel, Rhoderick E. Brown

Department of Biochemistry: Faculty Publications

The accelerated cell death 11 (acd11) mutant of Arabidopsis provides a genetic model for studying immune response activation and localized cellular suicide that halt pathogen spread during infection in plants. Here, we elucidate ACD11 structure and function and show that acd11 disruption dramatically alters the in vivo balance of sphingolipid mediators that regulate eukaryotic-programmed cell death. In acd11 mutants, normally low ceramide-1- phosphate (C1P) levels become elevated, but the relatively abundant cell death inducer phytoceramide rises acutely. ACD11 exhibits selective intermembrane transfer of C1P and phyto-C1P. Crystal structures establish C1P binding via a surface-localized, phosphate headgroup recognition center …

Unprecedented Heterogeneity In The Synonymous Substitution Rate Within A Plant Genome, Andan Zhu, Wenhu Guo, Kanika Jain, Jeffrey P. Mower

Center for Plant Science Innovation: Faculty Publications

The synonymous substitution rate varies widely among species, but it is generally quite stable within a genome due to the absence of strong selective pressures. In plants, plastid genes tend to evolve faster than mitochondrial genes, rate variation among species generally correlates between the mitochondrial and plastid genomes, and few examples of intragenomic rate heterogeneity exist. To study the extent of substitution rate variation between and within plant organellar genomes, we sequenced the complete mitochondrial and plastid genomes from the bugleweed, Ajuga reptans, which was previously shown to exhibit rate heterogeneity for several mitochondrial genes. Substitution rates were accelerated specifically …

Evaluation Of Constitutive Iron Reductase (Atfro2) Expression On Mineral Accumulation And Distribution In Soybean (Glycine Max. L), Marta W. Vasconcelos, Thomas E. Clemente, Michael A. Grusak

Center for Plant Science Innovation: Faculty Publications

Iron is an important micronutrient in human and plant nutrition. Adequate iron nutrition during crop production is central for assuring appropriate iron concentrations in the harvestable organs, for human food or animal feed. The whole-plant movement of iron involves several processes, including the reduction of ferric to ferrous iron at several locations throughout the plant, prior to transmembrane trafficking of ferrous iron. In this study, soybean plants that constitutively expressed the AtFRO2 iron reductase gene were analyzed for leaf iron reductase activity, as well as the effect of this transgene's expression on root, leaf, pod wall, and seed mineral concentrations. …

Identification Of Rna Silencing Components In Soybean And Sorghum, Xiang Liu, Tao Lu, Yongchao Dou, Bin Yu, Chi Zhang

Center for Plant Science Innovation: Faculty Publications

Background: RNA silencing is a process triggered by 21–24 small RNAs to repress gene expression. Many organisms including plants use RNA silencing to regulate development and physiology, and to maintain genome stability. Plants possess two classes of small RNAs: microRNAs (miRNAs) and small interfering RNAs (siRNAs). The frameworks of miRNA and siRNA pathways have been established in the model plant, Arabidopsis thaliana (Arabidopsis).

Results: Here we report the identification of putative genes that are required for the generation and function of miRNAs and siRNAs in soybean and sorghum, based on knowledge obtained from Arabidopsis. The gene families, including …

Methylation Protects Micrornas From An Ago1- Associated Activity That Uridylates 5′ Rna Fragments Generated By Ago1 Cleavage, Guodong Ren, Meng Xie, Shuxin Zhang, Carissa Vinovskis, Xuemei Chen, Bin Yu

Center for Plant Science Innovation: Faculty Publications

In plants, methylation catalyzed by HEN1 (small RNA methyl transferase) prevents microRNAs (miRNAs) from degradation triggered by uridylation. Howmethylation antagonizes uridylation of miRNAs in vivo is not well understood. In addition, 5′ RNA fragments (5′ fragments) produced by miRNA-mediated RNA cleavage can be uridylated in plants and animals. However, the biological significance of this modification is unknown, and enzymes uridylating 5′ fragments remain to be identified. Here, we report that in Arabidopsis, HEN1 suppressor 1 (HESO1, a miRNA nucleotidyl transferase) uridylates 5′ fragments to trigger their degradation.We also show that Argonaute 1 (AGO1), the effector protein of miRNAs, interacts …

Small Rnas Meet Their Targets: When Methylation Defends Mirnas From Uridylation, Guodong Ren, Xuemei Chen, Bin Yu

Center for Plant Science Innovation: Faculty Publications

Small RNAs are incorporated into Argonaute protein-containing complexes to guide the silencing of target RNAs in both animals and plants. The abundance of endogenous small RNAs is precisely controlled at multiple levels including transcription, processing and Argonaute loading. In addition to these processes, 3' end modification of small RNAs, the topic of a research area that has rapidly evolved over the last several years, adds another layer of regulation of their abundance, diversity and function. Here, we review our recent understanding of small RNA 3' end methylation and tailing.

Variation In The Local Population Dynamics Of The Short-Lived Opuntia Macrorhiza (Cactaceae), Chirakkal V. Haridas, Kathleen H. Keeler, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Spatio-temporal variation in demographic rates can have profound effects for population persistence, especially for dispersal-limited species living in fragmented landscapes. Long-term studies of plants in such habitats help with understanding the impacts of fragmentation on population persistence but such studies are rare. In this work we reanalyzed demographic data from seven years of the short-lived cactus Opuntia macrorhiza var. macrorhiza at five plots in Boulder, Colorado. Previous work combining data from all years and all plots predicted a stable population (deterministic log λ ≈ 0). This approach assumed that all five plots were part of a single population. Since the …

Quantitative Trait Locus Analysis Of Unsaturated Fatty Acids In A Recombinant Inbred Population Of Soybean, Xianzhi Wang, Guo-Liang Jiang, Marci Green, Roy A. Scott, D. L. Hyten, P. B. Cregan

Department of Agronomy and Horticulture: Faculty Publications

Soybean [Glycine max (L.) Merr.] is an important oilseed crop which produces about 30 %of the world’s edible vegetable oil. The quality of soybean oil is determined by its fatty acid composition. Soybean oil high in oleic and low in linolenic fatty acids is desirable for human consumption and other uses. The objectives of this study were to identify quantitative trait loci (QTLs) for unsaturated fatty acids and to evaluate the genetic effects of single QTL and QTL combinations in soybean. A population of recombinant inbred lines derived from the cross of SD02-4-59 X A02-381100 was evaluated for fatty …

Transcriptomic And Physiological Characterization Of The Fefe Mutant Of Melon (Cucumis Melo) Reveals New Aspects Of Iron-Copper Crosstalk, Brian M. Waters, Samuel A. Mcinturf, Keenan Amundsen

Department of Agronomy and Horticulture: Faculty Publications

Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. In previous work, Fe deficiency interacted with Cu-regulated genes and stimulated Cu accumulation. The C940-fe (fefe) Fe-uptake mutant of melon (Cucumis melo) was characterized, and the fefe mutant was used to test whether Cu deficiency could stimulate Fe uptake. Wild-type and fefe mutant transcriptomes were determined by RNA-seq under Fe and Cu deficiency. FeFe-regulated genes included core Fe uptake, metal homeostasis, and transcription factor genes. Numerous genes were regulated by both Fe and Cu. The fefe mutant was rescued by high Fe or by …

Four Common Setaria Species Are Alternative Hosts For Clavibacter Michiganensis Subsp. Nebraskensis, Causal Agent Of Goss's Bacterial Wilt And Blight Of Corn, Craig B. Langemeier, Tamra A. Jackson-Ziems, Greg R. Kruger

Department of Plant Pathology: Faculty Publications

Goss’s bacterial wilt and blight, caused by Clavibacter michiganensis subsp. nebraskensis (Cmn), has reemerged as an important disease of Zea mays (corn) in the U.S. Midwest. Results from a 2011 multistate survey indicated that Setaria spp. (foxtail) were often present in corn fields with a history of Cmn. The objective of this research was to determine if Setaria spp. that are common in the Midwest are susceptible to infection by Cmn. In the greenhouse, seedlings of four Setaria spp., including S. viridis (green foxtail), S. faberi (giant foxtail), S. verticillata (bristly foxtail), and S. pumila (yellow foxtail), and Zea mays …

What’S New In Plant Pathology, Tamra A. Jackson-Ziems, Loren Giesler, Robert M. Harveson, Stephen N. Wegulo, Kevin Korus

Department of Plant Pathology: Faculty Publications

Disease Management Products

During the past year several new products have become available for disease management. The new products are summarized in Tables 1 and 2, as well as included in the 2014 Guide for Weed Management in Nebraska with Insecticide and Fungicide Information. In addition, fungicides labeled for use on sorghum and sunflower have also been added to the publication.

Table 1. New Foliar Fungicides

Table 2. New Seed Nematicide

Disease Identification and Management Resources

Ficotylus Laselvae N. Sp. (Tylenchomorpha: Anguinidae) Associated With Ficus Colubrinae In Costa Rica, Robin M. Giblin-Davis, Natsumi Kanzaki, Kerrie A. Davies, Weimin Ye, Yongsan Zeng, Barbara J. Center, Alejandro Esquivel, Thomas O. Powers

Department of Plant Pathology: Faculty Publications

Ficotylus laselvae n. sp. was recovered from under the bracts of figs (syconia) of Ficus colubrinae from La Selva, Costa Rica, during a survey of nematode rainforest biodiversity and is described herein. This is only the second report of an association between the nematode suborder Tylenchina and the sycones of figs. Previous reports of most nematode associates of the sycones of figs have been from the lumen and involved transmission by female fig wasp pollinators (Agaonidae) during pollination/oviposition (e.g., Schistonchus and Parasitodiplogaster spp.). The association between F. laselvae n. sp. and Ficus colubrinae may involve an invertebrate host, …

Wheat Streak Mosaic Virus Infects Systemically Despite Extensive Coat Protein Deletions: Identification Of Virion Assembly And Cell-To-Cell Movement Determinants, Satyanarayana Tatineni, Frank A. Kovacs, Roy C. French

Department of Plant Pathology: Faculty Publications

Viral coat proteins function in virion assembly and virus biology in a tightly coordinated manner with a role for virtually every amino acid. In this study, we demonstrated that the coat protein (CP) of Wheat streak mosaic virus (WSMV; genus Tritimovirus, family Potyviridae) is unusually tolerant of extensive deletions, with continued virion assembly and/or systemic infection found after extensive deletions are made. A series of deletion and point mutations was created in the CP cistron of wild-type and/or green fluorescent protein-tagged WSMV, and the effects of these mutations on cell-to-cell and systemic transport and virion assembly of WSMV …

Phytophthora Ramorum, Sydney E. Everhart, Javier F. Tabima, Niklaus J. Grünwald

Department of Plant Pathology: Faculty Publications

Phytophthora ramorum is a recently emerged plant pathogen and causal agent of one of the most destructive and devastating diseases currently affecting US horticulture and forests (Rizzo et al. 2002, 2005). This oomycete pathogen was discovered in Marin County, California, in the mid-1990s, causing sudden oak death on coast live oak (Quercus agrifolia) and tanoak (Notholithocarpus densiflorus) and simultaneously discovered in Europe causing foliar blight on Rhododendron and Viburnum (Rizzo et al. 2002; Werres et al. 2001). It is now known to affect more than 100 plant species, including economically important nursery and forest host species …

Response Of Fusarium Thapsinum To Sorghum Brown Midrib Lines And To Phenolic Metabolites, Deanna L. Funnell-Harris, Scott E. Sattler, Jeffrey F. Pedersen

Department of Plant Pathology: Faculty Publications

Sorghum lines were bred for reduced lignin for cellulosic bioenergy uses, through the incorporation of brown midrib (bmr)6 or -12 into two backgrounds (RTx430 and Wheatland) as either single or doublemutant lines. When these lines were assessed for resistance to Fusarium thapsinum stalk rot, a cause of lodging, they were as resistant to F. thapsinum as the near-isogenic wild type. Peduncles of newly identified bmr lines from an ethyl-methanesulfonate-mutagenized population, inoculated with F. thapsinum, were as resistant as the wild-type line, BTx623. One bmr line (1107) had significantly smaller mean lesion lengths than BTx623, suggesting that a mutation …

Evidence For A Transketolase-Mediated Metabolic Checkpoint Governing Biotrophic Growth In Rice Cells By The Blast Fungus Magnaporthe Oryzae, Jessie Fernandez, Margarita Marroquin-Guzman, Richard A. Wilson

Department of Plant Pathology: Faculty Publications

The blast fungus Magnaporthe oryzae threatens global food security through the widespread destruction of cultivated rice. Foliar infection requires a specialized cell called an appressorium that generates turgor to force a thin penetration hypha through the rice cuticle and into the underlying epidermal cells, where the fungus grows for the first days of infection as a symptomless biotroph. Understanding what controls biotrophic growth could open new avenues for developing sustainable blast intervention programs. Here, using molecular genetics and live-cell imaging, we dismantled M. oryzae glucose-metabolizing pathways to reveal that the transketolase enzyme, encoded by TKL1, plays an essential role …

Identification Of A Sphingolipid Α-Glucuronosyltransferase That Is Essential For Pollen Function In Arabidopsis, Emilie A. Rennie, Berit Ebert, Godfrey P. Miles, Rebecca E. Cahoon, Katy M. Christiansen, Solomon Stonebloom, Hoda Khatab, David Twell, Christopher J. Petzold, Paul D. Adams, Paul Dupree, Joshua L. Heazlewood, Edgar B. Cahoon, Henrik Vibe Scheller

Department of Agronomy and Horticulture: Faculty Publications

Glycosyl inositol phosphorylceramide (GIPC) sphingolipids are a major class of lipids in fungi, protozoans, and plants. GIPCs are abundant in the plasma membrane in plants, comprising around a quarter of the total lipids in these membranes. Plant GIPCs contain unique glycan decorations that include a conserved glucuronic acid (GlcA) residue and various additional sugars; however, no proteins responsible for glycosylating GIPCs have been identified to date. Here, we show that the Arabidopsis thaliana protein INOSITOL PHOSPHORYLCERAMIDE GLUCURONOSYLTRANSFERASE1 (IPUT1) transfers GlcA from UDP-GlcA to GIPCs. To demonstrate IPUT1 activity, we introduced the IPUT1 gene together with genes for a UDP-glucose dehydrogenase …

Dynamics Of Small Rna Profiles Of Virus And Host Origin In Wheat Cultivars Synergistically Infected By Wheat Streak Mosaic Virus And Triticum Mosaic Virus: Virus Infection Caused A Drastic Shift In The Endogenous Small Rna Profile, Satyanarayana Tatineni, Jean-Jack M. Riethoven, Robert A. Graybosch, Roy French, Amitava Mitra

Department of Plant Pathology: Faculty Publications

Co-infection of wheat (Triticum aestivum L.) by Wheat streak mosaic virus (WSMV, a Tritimovirus) and Triticum mosaic virus (TriMV, a Poacevirus) of the family Potyviridae causes synergistic interaction. In this study, the effects of the synergistic interaction between WSMV and TriMV on endogenous and virus-derived small interfering RNAs (vsiRNAs) were examined in susceptible (‘Arapahoe’) and temperature-sensitive resistant (‘Mace’) wheat cultivars at 18 degrees C and 27 degrees C. Single and double infections in wheat caused a shift in the profile of endogenous small RNAs from 24 nt being the most predominant in healthy plants to 21 nt …

Quantification Of Yield Loss Caused By Triticum Mosaic Virus And Wheat Streak Mosaic Virus In Winter Wheat Under Field Conditions, E. Byamukama, S. N. Wegulo, S. Tatineni, G. L. Hein, R. A. Graybosch, P. Stephen Baenziger, R. French

Department of Plant Pathology: Faculty Publications

Triticum mosaic virus (TriMV) and Wheat streak mosaic virus (WSMV) infect winter wheat (Triticum aestivum) in the Great Plains region of the United States. The two viruses are transmitted by wheat curl mites (Aceria tosichella), which also transmit High Plains virus. In a field study conducted in 2011 and 2012, winter wheat cultivars Millennium (WSMV-susceptible) and Mace (WSMV-resistant) were mechanically inoculated with TriMV, WSMV, TriMV+WSMV, or sterile water at the two-leaf growth stage. Chlorophyll meter (soil plant analysis development [SPAD]) readings, area under the SPAD progress curve (AUSPC), grain yield (=yield), yield components (spikes/m², …

Studies On Sensitivity Reduction In Solo And Mixture Treatments And Fungicide-Induced Mutagenesis In Monilinia Fructicola, Guido Schnabel, F. Chen, Sydney E. Everhart, W. C. Bridges, X. Liu

Department of Plant Pathology: Faculty Publications

Three fungicide-sensitive Monilinia fructicola isolates were exposed in weekly transfers of mycelia to a dose gradient of a DMI and a QoI fungicide (azoxystrobin) in solo or mixture treatments and fungicide sensitivity as well as genetic changes were assessed. Isolates showed a faster reduction in sensitivity (higher resistance factors) to azoxystrobin than to SYP-Z048; this process was slower in the mixture treatment. The decrease of fungicide sensitivity was not a heritable trait. Genomic mutagenesis at 8 of 15 microsatellite loci was evidenced in one of three isolates tested after exposure to azoxystrobin. These non-coding regions of the genome either showed …

Methods For Using Cryptococcus Flavescens Strains For Biological Control Of Fusarium Head Blight, Brian B. Mcspadden Gardener, Pierce Anderson Paul, Michael J. Boehm, Xiaoqing Rong, David Schisler

Department of Plant Pathology: Faculty Publications

Disclosed are methods of identifying subspecies of Cryptococcus flavescens and methods of treating or suppressing Fusarium head blight with the different Cryptococcus flavescens species. In particular, two genotypes, Genotypes A and B, were identified using the disclosed real time PCR technique. The following Cryptococcus flavescens strains were identified as being either Genotype A or B and as being able to suppress Fusarium head blight: NRRLY-7373, YB-601, YB-602, Y-7377, Y-7372, Y-7375, Y-7374, Y-7376, YB-328, Y-7379, and YB-744.