Plant Pathology Commons^™

Arabidopsis Rna-Dependent Rna Polymerases And Dicer-Like Proteins In Antiviral Defense And Small Interfering Rna Biogenesis During Turnip Mosaic Virus Infection, Hernan Garcia-Ruiz, Atsushi Takeda, Elisabeth J. Chapman, Christopher M. Sullivan, Noah Fahlgren, Katherine J. Brempelis, James C. Carrington

Department of Plant Pathology: Faculty Publications

Plants respond to virus infections by activation of RNA-based silencing, which limits infection at both the single-cell and system levels. Viruses encode RNA silencing suppressor proteins that interfere with this response. Wild-type Arabidopsis thaliana is immune to silencing suppressor (HC-Pro)-deficient Turnip mosaic virus, but immunity was lost in the absence of DICER-LIKE proteins DCL4 and DCL2. Systematic analysis of susceptibility and small RNA formation in Arabidopsis mutants lacking combinations of RNA-dependent RNA polymerase (RDR) and DCL proteins revealed that the vast majority of virus derived small interfering RNAs (siRNAs) were dependent on DCL4 and RDR1, although full antiviral defense …

Meloidogyne Spp. Infecting Ornamental Plants In Florida, J. A. Brito, R. Kaur, R. Cetintas, J. D. Stanley, M. L. Mendes, Thomas O. Powers, D. W. Dickson

Department of Plant Pathology: Faculty Publications

A total of 206 root samples were collected from ornamental plants growing in ornamental nurseries and various landscapes in Florida. Isozyme phenotypes, especially esterase (EST) and malate dehydrogenase (MDH) were the main methods used to identify the root-knot nematode species. When needed, the morphology of female perineal patterns, morphometric characters and mitochondrial DNA were used to aid in the identification. Six Meloidogyne spp., M. arenaria , M. floridensis , M. graminis , M. incognita , M. javanica and M. mayaguensis were found infecting ornamental plants in Florida. As previously reported EST activity was of highest diagnostic value to identify Meloidogyne …

Importance Of Myxomycetes In Biological Research And Teaching, Harold W. Keller, Sydney E. Everhart

Department of Plant Pathology: Faculty Publications

Myxomycetes, the true slime molds, are highlighted in research and teaching that emphasizes various stages of the life cycle as experimental models. Past and current phylogenetic classifications of Myxomycetes on the tree of life are presented. Life cycle stages are illustrated, described, and discussed. Simple laboratory demonstrations and experiments are described that include spore germination, spore release, and moist chamber cultures utilizing organic matter from various microhabitats. Novel compounds isolated from fruiting bodies and plasmodia of 22 myxomycete species are tabulated, some of which exhibit biological activity that function as antibiotics, antimicrobials, and are cytotoxic to cancer cells. Aeroallergens include …

Shiga Toxin Is Transported Into The Nucleoli Of Intestinal Epithelial Cells Via A Carrier-Dependent Process, Boris Baibakov, Rakhilya Murtazina, Christian Elowsky, Francis M. Giardiello, Olga Kovbasnjuk

Department of Plant Pathology: Faculty Publications

Shiga toxin (Stx) produced by the invasive Shigella dysenteriae serotype 1 (S. dysenteriae1) causes gastrointestinal and kidney complications. It has been assumed that Stx is released intracellularly after enterocyte invasion by S. dysenteriae1. However, there is little information about Stx distribution inside S. dysenteriae1-infected enterocytes. Here, we use intestinal epithelial T84 cells to characterize the trafficking of Stx delivered into the cytosol, in ways that mimic aspects of S. dysenteriae1 infection. We find that cytoplasmic Stx is transported into nucleoli. Stx nucleolar movement is carrier- and energy-dependent. Stx binding to the nucleoli of normal human …

Summer Heat And An Epidemic Of Cytospora Canker Of Alnus, James J. Worrall, Gerard C. Adams, Sarah C. Tharp

Department of Plant Pathology: Faculty Publications

An epidemic of cytospora canker [Valsa melanodiscus, anamorph Cytospora umbrina] is associated with dieback and mortality of Alnus incana ssp. tenuifolia in the Southern Rocky Mountains and had begun by the late 1980s. Isolations showed that inoculum was often abundant on bark and bud surfaces even in winter, especially near diseased stems. The pathogen was occasionally isolated from internal tissues of dormant buds and asymptomatic wood and phloem. In infected stems, the pathogen was detected up to 5 cm beyond visible canker margins. The data suggest that the pathogen can cause latent infections, but the infection court …

The Pathogenicity Determinant Of Citrus Tristeza Virus Causing The Seedling Yellows Syndrome Maps At The 3′-Terminal Region Of The Viral Genome, Maria R. Albiach-Marti, Cecile J. Robertson, Siddarame Gowda, Satyanarayana Tatineni, Belen Belliure, Stephen M. Garnsey, Svetlana Y. Folimonova, Pedro Moreno, William O. Dawson

Department of Plant Pathology: Faculty Publications

Citrus tristeza virus (CTV) (genus Closterovirus, family Closteroviridae) causes some of the more important viral diseases of citrus worldwide. The ability to map disease-inducing determinants of CTV is needed to develop better diagnostic and disease control procedures. A distinctive phenotype of some isolates of CTV is the ability to induce seedling yellows (SY) in sour orange, lemon and grapefruit seedlings. In Florida, the decline isolate of CTV, T36, induces SY, whereas a widely distributed mild isolate, T30, does not. To delimit the viral sequences associated with the SY syndrome, we created a number of T36/T30 hybrids by substituting T30 …

Heterologous Minor Coat Proteins Of Citrus Tristeza Virus Strains Affect Encapsidation, But The Coexpression Of Hsp70h And P61 Restores Encapsidation To Wild-Type Levels, Satyanarayana Tatineni, Siddarame Gowda, William O. Dawson

Department of Plant Pathology: Faculty Publications

The long flexuous bipolar virions of Citrus tristeza virus (CTV), a Closterovirus, are encapsidated with two capsid proteins at opposite ends: the minor coat protein (CPm) encapsidates the 5′ 630 nts of the genomic RNA and the major coat protein encapsidates the remainder of the genome. In this study, we found encapsidation of CTV CPm in the absence of other assembly-related proteins is highly specific in contrast to most plant viruses that allow virion assembly by a range of heterologous coat proteins. Heterologous CPms with 95–96% amino acid identity from related strains in CTV-CPm, a replicon with CPm as …

Soil And Root Populations Of Fluorescent Pseudomonas Spp. Associated With Seedlings And Field-Grown Plants Are Affected By Sorghum Genotype, Deanna L. Funnell-Harris, Jeffrey F. Pedersen, Scott E. Sattler

Department of Plant Pathology: Faculty Publications

Sorghum [Sorghum bicolor (L.) Moench] is valued for bioenergy, feed and food. Potential of sorghum genotypes to support differing populations of root- and soil-associated fluorescent Pseudomonas spp. or Fusarium spp., in two soils, was assessed. Culturable pseudomonads were enumerated from roots and soil of sorghum (Redlan and RTx433) and wheat (Lewjain) seedlings repeatedly grown in cycled soils in the growth chamber. Pseudomonads and Fusarium spp. were assessed from roots and soil of field-grown sorghum along with biological control traits hydrogen cyanide (HCN) and 2,4-diacetylphlorogluconol (phl) production. After four 4-week cycles, soil associated with Redlan seedlings had greater numbers …

Brown Midrib Mutations And Their Importance To The Utilization Of Maize, Sorghum, And Pearl Millet Lignocellulosic Tissues, Scott E. Sattler, Deanna L. Funnell-Harris, Jeffrey F. Pedersen

Department of Plant Pathology: Faculty Publications

Brown midrib mutants have been isolated in maize (Zea mays), sorghum (Sorghum bicolor) and pearl millet (Pennisetum glaucum) arising by either spontaneous or chemical mutagenesis. The characteristic brown coloration of the leaf mid veins is associated with reduced lignin content and altered lignin composition, traits useful to improve forage digestibility for livestock. Brown midrib phenotype is correlated with two homologous loci in maize (bm1 and bm3) and sorghum (bmr6 and bmr12), which encode cinnamyl alcohol dehydrogenase (CAD) and a caffeic O-methyl transferase (COMT). These enzymes are involved in the last …

Upper Canopy Collection And Identification Of Grapevines (Vitis) From Selected Forests In The Southeastern United States, Sydney E. Everhart

Department of Plant Pathology: Faculty Publications

Woody grapevines (Vitis spp.) are common in the deciduous forests of the southeastern United States. Their growth habit makes leaf collection challenging and polymorphic leaves make identification of species difficult. Mature grapevines can grow up to 48 cm in diameter at breast height and reach the upper canopy of trees more than 35 m in height. Leaf morphology is the most readily available character used for species identification. However, most mature grapevines do not produce leaves below the upper canopy and if they do, these leaves are morphologically indistinguishable from other species. In order to sample leaves from …

Regulation Of Septum Formation By The Bud3–Rho4 Gtpase Module In Aspergillus Nidulans, Haoyu Si, Daniela Justa-Schuch, Stephan Seiler, Steven D. Harris

Department of Plant Pathology: Faculty Publications

The ability of fungi to generate polarized cells with a variety of shapes likely reflects precise temporal and spatial control over the formation of polarity axes. The bud site selection system of Saccharomyces cerevisiae represents the best-understood example of such a morphogenetic regulatory system. However, the extent to which this system is conserved in the highly polarized filamentous fungi remains unknown. Here, we describe the functional characterization and localization of the Aspergillus nidulans homolog of the axial bud site marker Bud3. Our results show that AnBud3 is not required for polarized hyphal growth per se, but is involved in septum …

An In Vitro Method For The Analysis Of Infection-Related Morphogenesis In Fusarium Graminearum, William R. Rittenour, Steven D. Harris

Department of Plant Pathology: Faculty Publications

Fusarium graminearum is a significant pathogen of many cereal crops. With its genetic tractability, ease of culture, genome sequence availability and economic significance, F. graminearum has become the subject of intensive molecular research. Although molecular tools have been developed to enhance research into virulence determinants of F. graminearum, simple assays for infection-related development are lacking. As such, the objective of this study was to develop an in vitro protocol for the analysis of infection-related morphogenesis in F. graminearum. We demonstrate that two morphologically distinct hyphal structures are produced by F. graminearum during the invasion of detached wheat glumes: subcuticular hyphae …

Deep And Comparative Transcriptome Analysis Of Rice Plants Infested By The Beet Armyworm (Spodoptera Exigua) And Water Weevil (Lissorhoptrus Oryzophilus), R. C. Venu, M. Sheshu Madhav, M. V. Sreerekha, Kan Nobuta, Yuan Zhang, Peter Carswell, Michael J. Boehm, B. C. Meyers, Kenneth L. Korth, Guo-Liang Wang

Department of Plant Pathology: Faculty Publications

The beet armyworm (Spodoptera exigua) and the rice water weevil (Lissorhoptrus oryzophilus) are two important insect pests in rice production. To identify insect-responsive genes in rice, we performed a deep transcriptome analysis of Nipponbare rice leaves infested with both beet armyworm and water weevil using massively parallel signature sequencing (MPSS). Many antisense, alternative, and novel transcripts were commonly and specifically induced and suppressed in the infested tissue. Key genes involved in the defense metabolic pathways such as salicylic acid and jasmonic acid biosynthesis pathways were up-regulated in the infested leaves. To validate theMPSS results, we analyzed …

Education In Plant Pathology Present Status And Future Challenges, James Macdonald, Caitilyn Allen, David Gadoury, William Jacobi, Segenet Kelemu, James Moyer, Tim Murray, Kevin Ong, Charles Pearson, John Sherwood, Ann Vidaver

Department of Plant Pathology: Faculty Publications

Plant pathology is largely a mission driven discipline that seeks to increase the fundamental understanding of host–pathogen interactions and the etiology of plant diseases for the purpose of preventing or mitigating crop loss. This is an important mission because all nations face serious challenges in their efforts to prevent disease on plants cultivated for food, fiber, ornamental use, timber, and fuel, as well as those growing in native ecosystems. In 1994, it was estimated that global losses due to plant diseases ranged from 9.7 to 14.2% of potential yield (12).

Triticum Mosaic Virus: A Distinct Member Of The Family Potyviridae With An Unusually Long Leader Sequence, Satyanarayana Tatineni, Amy D. Ziems, Stephen N. Wegulo, Roy French

Department of Plant Pathology: Faculty Publications

The complete genome sequence of Triticum mosaic virus (TriMV), a member in the family Potyviridae, has been determined to be 10,266 nucleotides (nt) excluding the 3′ polyadenylated tail. The genome encodes a large polyprotein of 3,112 amino acids with the “hall-mark proteins” of potyviruses, including a small overlapping gene, PIPO, in the P3 cistron. The genome of TriMV has an unusually long 5′ nontranslated region of 739 nt with 12 translation initiation codons and three small open reading frames, which resemble those of the internal ribosome entry site containing 5′ leader sequences of the members of Picornaviridae. Pairwise …

A Nonsense Mutation In A Cinnamyl Alcohol Dehydrogenase Gene Is Responsible For The Sorghum Brown Midrib6 Phenotype1[W][Oa], Scott E. Sattler, Aaron J. Saathoff, Eric J. Haas, Nathan A. Palmer, Deanna L. Funnell-Harris, Gautam Sarath, Jeffrey F. Pedersen

Department of Plant Pathology: Faculty Publications

brown midrib6 (bmr6) affects phenylpropanoid metabolism, resulting in reduced lignin concentrations and altered lignin composition in sorghum (Sorghum bicolor). Recently, bmr6 plants were shown to have limited cinnamyl alcohol dehydrogenase activity (CAD; EC 1.1.1.195), the enzyme that catalyzes the conversion of hydroxycinnamoyl aldehydes (monolignals) to monolignols. A candidate gene approach was taken to identify Bmr6. Two CAD genes (Sb02g024190 and Sb04g005950) were identified in the sorghum genome based on similarity to known CAD genes and through DNA sequencing a nonsense mutation was discovered in Sb04g005950 that results in a truncated protein lacking the NADPH-binding and C-terminal …

Plant Growth-Promoting Rhizobacteria Allow Reduced Application Rates Of Chemical Fertilizers, A. O. Adesemoye, H. A. Torbert, J. W. Kloepper

Department of Plant Pathology: Faculty Publications

The search for microorganisms that improve soil fertility and enhance plant nutrition has continued to attract attention due to the increasing cost of fertilizers and some of their negative environmental impacts. The objectives of this greenhouse study with tomato were to determine (1) if reduced rates of inorganic fertilizer coupled with microbial inoculants will produce plant growth, yield, and nutrient uptake levels equivalent to those with full rates of the fertilizer and (2) the minimum level to which fertilizer could be reduced when inoculants were used. The microbial inoculants used in the study were a mixture of plant growth-promoting rhizobacteria …

First Report Of Columbia Root-Knot Nematode (Meloidogyne Chitwoodi) In Potato In Turkey, A. Ozarslandan, Z. Devran, N. Mutlu, I. H. Elekcioglu

Department of Plant Pathology: Faculty Publications

Columbia root-knot nematode, Meloidogyne chitwoodi Golden et al., was identified from potatoes, Solanum tuberosum L., collected from Nigde Province, Turkey in September 2006. Seed potatoes are the most likely source for this introduction. The nematode is currently found to be infecting potatoes grown in the Netherlands, Portugal, Belgium, Germany, the United States, Mexico, South Africa, and Argentina. M. chitwoodi acquired a quarantine status in Europe (1) because of its potential to become established worldwide and its high damage probability. Some countries prohibit import of both seed and table stock potatoes originating in states known to harbor M. chitwoodi. Lesions …

Crop Updates 2009 - Farming Systems, Derk Bakker, Grey Poulish, Steve Lacy, Svetlana Micic, Peter Mangano, Tony Dore, Alan Lord, Vivien Vanstone, Helen Hunter, Sean Kelly, W. K. Anderson, Gary Lang, David Mccarthy, Ruhi Ferdowsian, Ian Rose, Andrew Van Burgel, David Ferris, Rob Grima, Natalie Hogg, John Davis, Jarrad Martin, Pippa Michael, Robert Belford, Kawsar P. Salam, Roy Murray-Prior, David Bowran, Moin U. Salam, Tim Scanlon, Len Wade, Megan Ryan, Megan Abrahams, Chad Reynolds, Caroline Peek, Dennis Van Gool, Kari-Lee Falconer, Daniel Gardiner, Geoff Anderson, Siva Sivapalan, Tim Mcclelland, James Hunt, Zvi Hochman, Bill Long, Dean Holzworth, Anthony Whitbread, Stephen Van Rees, Peter Devoil, Yvette Oliver, Michael Robertson, Peter Stone

Crop Updates

This session covers nineteen papers from different authors:

Decision support technology

1. The use of high resolution imagery in broad acre cropping, Derk Bakker and Grey Poulish, Department of Agriculture and Food

2. Spraywise decisions – online spray applicatiors planning tool, Steve Lacy, Nufarm Australia Ltd

3. Testing for redlegged earthmite resistance in Western Australia, Svetlana Micic, Peter Mangano, Tony Dore and Alan Lord, Department of Agriculture and Food

4. Screening cereal, canola and pasture cultivars for Root Lesion Nematode (Pratylenchus neglectus), Vivien Vanstone, Helen Hunter and Sean Kelly,Department of Agriculture and Food

Farming Systems Research

5. …

Evaluating Pseudomonas Aeruginosa As Plant Growth–Promoting Rhizobacteria In West Africa, Anthony O. Adesemoye, Esther O. Ugoji

Department of Plant Pathology: Faculty Publications

Some parameters of growth were examined in three test crops as indices of plant growth–promoting rhizobacteria (PGPR) ability of Pseudomonas aeruginosa. Crops include Abelmoschus esculentus L. (okra), Lycopersicon esculentum L. (tomato), and Amaranthus sp. (African spinach). This study aimed to examine the effectiveness of PGPR in West Africa and determine whether the inoculation method has an impact on PGPR’s effectiveness. Bacterium was isolated from topsoil in the Botanical Garden, University of Lagos, Nigeria. Inoculation with bacteria was done by soaking seeds in 10⁶ cfu/ml of bacterial suspension, and coating was done using 10% starch (w/v) as seed adhesive …

Effects Of Increased Pco2 And Temperature On The North Atlantic Spring Bloom. Iii. Dimethylsulfoniopropionate, Peter A. Lee, Jamie R. Rudisill, Aimee R. Neeley, Jennifer M. Maucher, David A. Hutchins, Yuanyuan Feng, Clinton E. Hare, Karine Leblanc, Julie M. Rose, Steven W. Wilhelm, Janet M. Rowe, Giacomo R. Ditullio

Department of Plant Pathology: Faculty Publications

The CLAW hypothesis argues that a negative feedback mechanism involving phytoplankton- derived dimethylsulfoniopropionate (DMSP) could mitigate increasing sea surface temperatures that result from global warming. DMSP is converted to the climatically active dimethylsulfide (DMS), which is transferred to the atmosphere and photochemically oxidized to sulfate aerosols, leading to increases in planetary albedo and cooling of the Earth’s atmosphere. A shipboard incubation experiment was conducted to investigate the effects of increased temperature and pCO₂ on the algal community structure of the North Atlantic spring bloom and their subsequent impact on particulate and dissolved DMSP concentrations (DMSP_p and DMSP_{d …}

Accumulation Of A 5′ Proximal Subgenomic Rna Of Citrus Tristeza Virus Is Correlated With Encapsidation By The Minor Coat Protein, Siddarame Gowda, Satyanarayana Tatineni, Svetlana Y. Folimonova, Mark E. Hilf, William O. Dawson

Department of Plant Pathology: Faculty Publications

During replication, Citrus tristeza virus (CTV) produces large amounts of two unusual subgenomic (sg) RNAs that are positive-stranded and 5′ coterminal. Although these RNAs are produced in similar amounts and are similar in size, with LMT1 (~750 nt) only slightly larger than LMT2 (~650), we found that the similar sgRNAs are produced differently. We previously showed that the LMT1 RNA is produced by premature termination during genomic RNA synthesis. However, LMT2 production was found to correlate with virion assembly instead of RNA replication. The time course of accumulation of the LMT2 RNA occurred late, coinciding with virion accumulation. The long …

Choline-Utilizing Microblal Strains For Biologically Controlling Fusarium Head Blight, David A. Schisler, Naseem I. Khan, Michael J. Boehm, Patricia J. Slininger

Department of Plant Pathology: Faculty Publications

Three choline utilizing strains of microorganisms isolated from the anthers of wheat, Aureobasidium pullulans strainAS 55.2, Arthrobacter species strain OH 221.3, and Pseudomonas species strain AS 64.4, are superior antagonists of F. graminearum. These microorganisms are effective for suppression and control of FHB in cereals, particularly in wheat and barley.

Dollar Spot Fungus Sclerotinla Homoeocarpa Produces Oxalic Acid, R. C. Venu, Robert A. Beaulieu, Terrance L. Graham, Ainhoa Martinez Medina, Michael J. Boehm

Department of Plant Pathology: Faculty Publications

Dollar spot, caused by Sclerotinia homoeocarpa,. is one of the most devastating diseases of turfgrass worldwide. Many fungi belonging to the genus Sclerotinia produce oxalic acid along with pectolytic cell wall-degrading enzymes. A series of in vitro experiments showed the relationships among temperature, pH, mycelial growth and acid production. Mycelial growth and acid production were most abundant when S. homoeocarpa was grown between 20 and 30°C. Acid production by S. homoeocarpa appeared to be dependent upon the pH of the environment in which it was grown. High performance liquid chromatography analysis of spent broth revealed the presence of oxalic acid. …

Molecular Characterization Of Citrus Tatter Leaf Virus Historically Associated With Meyer Lemon Trees: Complete Genome Sequence And Development Of Biologically Active In Vitro Transcripts, Satyanarayana Tatineni, Mohammad R. Afunian, Mark E. Hilf, Siddarame Gowda, William O. Dawson, Stephen M. Garnsey

Department of Plant Pathology: Faculty Publications

Citrus tatter leaf virus isolated from Meyer lemon trees (CTLV-ML) from California and Florida induces bud union incompatibility of citrus trees grafted on the widely used trifoliate and trifoliate hybrid rootstocks. The complete genome sequence of CTLV-ML was determined to be 6,495 nucleotides (nts), with two overlapping open reading frames (ORFs) and a poly (A) tail at the 3′ end. The genome organization is similar to other capilloviruses, with ORF1 (nts 37 to 6,354) encoding a putative 242-kDa polyprotein which contains replication-associated domains plus a coat protein (CP), and ORF2 (nts 4,788 to 5,750), which is located within ORF1 in …

Plant-Microbes Interactions In Enhanced Fertilizer-Use Efficiency, Anthony O. Adesemoye, Joseph W. Kloepper

Department of Plant Pathology: Faculty Publications

The continued use of chemical fertilizers and manures for enhanced soil fertility and crop productivity often results in unexpected harmful environmental effects, including leaching of nitrate into groundwater, surface runoff of phosphorus and nitrogen runoff, and eutrophication of aquatic ecosystems. Integrated nutrient management systems are needed to maintain agricultural productivity and protect the environment. Microbial inoculants are promising components of such management systems. This review is a critical summary of the efforts in using microbial inoculants, including plant growth-promoting rhizobacteria and arbuscular mycorrhizal fungi for increasing the use efficiency of fertilizers. Studies with microbial inoculants and nutrients have demonstrated that …

Integrated Management Strategies For Phytophthora Sojae Combining Host Resistance And Seed Treatments, A. E. Dorrance, A. E. Robertson, S. Cianzo, L. J. Giesler, C. R. Grau, M. A. Draper, A. U. Tenuta, T. R. Anderson

Department of Plant Pathology: Faculty Publications

Phytophthora sojae has re-emerged as a serious soybean pathogen in the past decade. This may be due in part to changes in resistance levels in current cultivars, adoption of P. sojae populations to deployed Rps genes, and highly favorable environments in the past decade. This multilocation study evaluated the effect of seed treatments on the incidence and severity of Phytophthora root and stem rot on soybeans with different combinations of Rps genes and levels of partial resistance. The efficacy of the seed treatments was highly variable across locations. Seed treatments (metalaxyl and mefenoxam) provided protection and increased yields across cultivars …

First Report Of Soybean Rust Caused By Phakopsora Pachyrhizi In Nebraska, S. R. Watson, L. J. Giesler, A. D. Ziems, T. E. Brovont

Department of Plant Pathology: Faculty Publications

Soybean rust caused by Phakopsora pachyrhizi Sydow was first observed in the continental United States in Louisiana in November 2004 (2). As part of the national soybean rust monitoring effort, samples were collected on 3 October 2007 during the scouting of fields with green leaves in southeastern Nebraska. After incubation at room temperature for 24 h, uredinea and urediniospores were observed with microscopic examination. Urediniospores were obovoid, hyaline to pale brown, and measured 20 to 30 × 18 to 20 μm.

Enhanced Plant Nutrient Use Efficiency With Pgpr And Amf In An Integrated Nutrient Management System, A. O. Adesemoye, H. A. Torbert, J. W. Kloepper

Department of Plant Pathology: Faculty Publications

A 3-year field study was conducted with field corn from 2005 to 2007 to test the hypothesis that microbial inoculants that increase plant growth and yield can enhance nutrient uptake, and thereby remove more nutrients—especially N, P, and K—from the field as part of an integrated nutrient management system. The field trial evaluated microbial inoculants, which include a commercially available plant growth-promoting rhizobacteria (PGPR), arbuscular mycorrhiza fungi (AMF), and their combination across 2 tillage systems (no-till and conventional till) and 2 fertilization regimes (poultry litter and ammonium nitrate). Data were collected on plant height, yield (dry mass of ears and …

Method For Efficient Post Transcriptional Gene Slencing Using Intrinsic Direct Repeat Sequences And Utilization Thereof Infunctional Genomics, Amitava Mitra, Chonglie Ma

Department of Plant Pathology: Faculty Publications

It is well documented that transgenes with inverted repeats can efficiently trigger post-transcriptional gene silencing (PTGS), presumably via a double stranded RNA induced by complementary sequences in their transcripts. We show here that transgenes with intrinsic direct repeats can also induce PTGS at a very high frequency (80-100%). A transgene with three or four repeats induced PTGS in almost 100% of the primary transformants, regardless of whether a strong (en hanced 35S promoter) or a relatively weak (chlorophyll a?b binding protein promoter) promoter was used. The PTGS induced by three or four repeats is consistently inherited in Subsequent generations, and …