Life Sciences Commons^™

Nuclear Localization Of Turnip Crinkle Virus Movement Protein P8, Yuval Cohen, Feng Qu, Andreas Gisel, Thomas Jack Morris, Patricia Zambryski

Department of Plant Pathology: Faculty Publications

Turnip crinkle virus (TCV) is a single-stranded positive-sense RNA virus of the Carmovirus genus. Two of its five open reading frames (ORFs), encoding proteins of 8 and 9 kDa, are required for cell-to-cell movement of the virus. These movement proteins (MPs) were fused to green fluorescent protein (GFP) to determine their cellular localization. In protoplasts, p9-GFP, like GFP itself, is found throughout the cytoplasm, as well as in cell nuclei. In contrast, p8-GFP was confined to the cell nucleus. Similar localization patterns were observed when specific small peptide epitopes were fused to p8 and p9 proteins instead of GFP. The …

Utility Of The Mitochondrial Cytochrome Oxidase Ii Gene For Resolving Relationships Among Black Flies (Diptera: Simuliidae), K. P. Pruess, B. J. Adams, T. J. Parsons, X. Zhu, Thomas O. Powers

Department of Plant Pathology: Faculty Publications

The complete mitochondrial cytochrome oxidase II gene was sequenced from 17 black flies, representing 13 putative species, and used to infer phylogenetic relationships. A midge (Paratanytarsus sp.) and three mosquitoes (Aedes aegypti, Anopheles quadrimaculatus, and Culex quinquefasciatus) were used as outgroup taxa. All outgroup taxa were highly divergent from black flies. Phylogenetic trees based on weighted parsimony (a priori and a posteriori), maximum likelihood, and neighbor-joining (log-determinant distances) differed topologically, with deeper nodes being the least well-supported. All analyses supported current classification into species groups but relationships among those groups were poorly resolved. The majority of phylogenetic …

A Plant Virus Vector For Systemic Expression Of Foreign Genes In Cereals, Il-Ryong Choi, Drake C. Stenger, Thomas Jack Morris, Roy C. French

Department of Plant Pathology: Faculty Publications

Inserts bearing the coding sequences of NPTll and P-glucuronidase (GUS) were placed between the nuclear inclusion b (Nlb) and coat protein (CP) domains of the wheat streak mosaic virus (WSMV) polyprotein ORF. The WSMV Nlb-CP junction containing the nuclear inclusion a (Nla) protease cleavage site was duplicated, permitting excision of foreign protein domains from the viral polyprotein. Wheat, barley, oat and maize seedlings supported systemic infection of WSMV bearing NPTII. The NPTII insert was stable for at least 18-30 days post-inoculation and had little effect on WSMV CP accumulation. Histochemical assays indicated the presence of functional GUS protein in systemically …

The Open Reading Frame 5a Of Foxtail Mosaic Virus Is Expressed In Vivo And Is Dispensable For Systemic Infection, N.L. Robertson, Roy C. French, Thomas Jack Morris

Department of Plant Pathology: Faculty Publications

Infectious transcripts were successfully derived from full-length cDNA clones of foxtail mosaic potexvirus (FoMV). Full-length clones were constructed by RT-PCR whereby 50 and 30 genomic segments of 2.7 and 3.4 kb, respectively, were ligated into Bluescript II KS. The in vitro RNA transcripts were infectious to moncotyledonous (barley) and dicotyledonous (Chenopodium amaranticolor) plant species. Individual mutation studies on clones of each of the five major ORFs confirmed predicted gene function for the polymerase, TGB (triple gene block), and coat protein (CP) genes. Protoplast studies on expression of a unique open reading frame, ORF 5A, which initiates 143 nts …

Fertilisers For Wine Grapes : An Information Package To Promote Efficient Fertiliser Practices, B. H. Goldspink, Neil Lantzke, Bob Paulin, Diana Louise Fisher, Colin Gordon, N. Cross, J M. Campbell-Clause

Bulletins 4000 -

No abstract provided.

A Potassium Channel Protein Encoded By Chlorella Virus Pbcv-1, B. Plugge, S. Gazzarrini, M. Nelson, R. Cerana, James L. Van Etten, C. Derst, D. Difrancesco, A. Moroni, G. Thiel

Department of Plant Pathology: Faculty Publications

The large chlorella virus PBCV-1, which contains double-stranded DNA (dsDNA), en¬codes a 94-codon open reading frame (ORF) that contains a motif resembling the signature se¬quence of the pore domain of potassium channel proteins. Phylogenetic analyses of the encoded protein, Kcv, indicate a previously unidentified type of potassium channel. The messenger RNA encoded by the ORF leads to functional expression of a potassium-selective conductance in Xen¬opus laevis oocytes. The channel blockers amantadine and barium, but not cesium, inhibit this conductance, in addition to virus plaque formation. Thus, PBCV-1 encodes the first known viral protein that functions as a potassium-selective channel and …

Condition Of Green Ash, Incidence Of Ash Yellows Phytoplasmas, And Their Association In The Great Plains And Rocky Mountain Regions Of North America, J. A. Walla, W. R. Jacobi, N. A. Tisserat, M. O. Harrell, J. J. Ball, G. B. Neil, D. A. Reynard, Y. H. Guo, L. Spiegel

Department of Plant Pathology: Faculty Publications

About 50% of 1,057 green ash (Fraxinus pennsylvanica) systematically sampled in the Great Plains and Rocky Mountain regions had substantial dieback (>10% of crown branches with dieback), and the average growth ring width during the last 20 years was 2.9 mm. The overall condition of the population was rated fair. Ash yellows phytoplasmas were identified at 102 of 106 sites throughout six U.S. states (North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas) and three Canadian provinces (Alberta, Saskatchewan, Manitoba). These phytoplasmas had not previously been known in Alberta, Saskatchewan, Manitoba, Wyoming, Colorado, or Kansas. Incidence of phytoplasmal …

Characterization Of North American Armillaria Species By Nuclear Dna Content And Rflp Analysis, Mee-Sook Kim, Ned Klopfenstein, Geral I. Mcdonald, Kathiravetpillai Arumuganathan, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

Twenty-six isolates representing nine North American Armillaria species were investigated with flow cytometry and RFLP (restriction fragment length polymorphism) analyses to determine their nuclear DNA content and RFLP profile. Three putatively diploid isolates of A. ostoyae, A. gemina, A. calvescens, A. sinapina, A. mellea, A. gallica, A. nabsnona, and North American Biological Species (NABS) X were analyzed, and two putatively diploid isolates of NABS XI also were analyzed. Nuclear DNA contents of Armillaria species were 0.11-0.17 pg per nucleus (55-84 X 10" bp/C), depending on species. Among the nine North American Armillaria species tested, A. ostoyae, A. gemirza, and …

Crop Updates 2000 - Pulses, Kerry Regan, Peter White, Kamdambot Siddique, W. O'Neill, J. Russell, R. J. French, N. Brandon, C. Gaskin, N. Runciman, M. Seymore, J. Berger, N. C. Turner, R. Carpenter, C. Ludwig, R. Kenny, Q. Ma, M. H. Behboudian, J. A. Palta, H. Clarke, J. Stott, J. Howieson, K. L. Regan, R. Shackles, C. Francis, N. Acikgoz, N. Atikyilmaz, R. S. Malholtra, M. Baker, J. Clements, C. Hanbury, C. White, B. P. Mullan, R. Lancaster, I. Guthridge, I. Pritchard, P. Fisher, M. Braimbridge, J. Bignell, R. Beermier, W. Bowden, M. D. A. Bolland, G. P. Riethmuller, R. F. Brennan, S. Lawrence, Zen Rengel, S. P. Loss, P. Vedeniapine, C. Kirkwood, D. Wright, L. Latham, R. Jones, M. J. De Sousa Majer, D. Hardie, Oonagh Byrne, Penny Smith, Françoise Berlandier, N. Keals, R. Emery

Crop Updates

This session covers fifty nine papers from different authors:

1.1999 PULSE INDUSTRY HIGHLIGHTS

2. CONTRIBUTORS

3. BACKGROUND

4. SUMMARY OF PREVIOUS RESULTS

5. 1999 REGIONAL ROUNDUP

6. Northern Agricultural Region^, W. O’Neill, AGWEST

7. Central Agricultural Region J. Russell and R.J. French AGWEST

8. Great Southern and Lakes N. Brandon, C. Gaskin and N. Runciman, AGWEST

9. Esperance Mallee M. Seymour, AGWEST

PULSE PRODUCTION AGRONOMY AND GENETIC IMPROVEMENT

10. Faba Bean

11. Desi chickpea Traits associated with drought resistance in chickpea, J. Berger, N.C. Turner, CLIMA and CSIRO Plant Industry, R.J. French, AGWEST, R. Carpenter, C. Ludwig and R. …

Crop Updates 2000 - Cereals Part 1, Timothy G. Reeves, Sanjaya Rajaram, Maarten Van Ginkel, Richard Trethowan, Hans-Joachim Braun, Kelly Cassaday, R. A. Mcintosh, Rob Loughman, Ross Brennan, Mike Bolland, Zed Rengel, David Isbister, Paul Blackwell, Derk Bakker, Greg Hamilton, David Houlbrooke, Cliff Spann, Doug Rowe, Patrick Gethin, Stephen Loss, Frank Boetel, Tim O'Dea, Noeleen Edwards, Wayne Pluske, Ross Brennan, M. T. F. Wong, K. Wittwer, H. Zhang

Crop Updates

This session covers eleven papers from different authors:

PLENARY PAPERS

1. New Wheat for a Secure, Sustainable Future, Timothy G. Reeves, Sanjaya Rajaram, Maarten van Ginkel, Richard Trethowan, Hans-Joachim Braun, and Kelly Cassaday, International Maize and Wheat Improvement Centre (CIMMYT)

2. Managing Cereal Rusts - a National Perspective, R.A. McIntosh, University of Sydney Plant Breeding Institute, New South Wales

3. Managing Cereal Rusts in 2000 - a regional imperative, R. Loughman, Agriculture Western Australia

4. Is nutrition the answer to wheat after canola problems?Ross Brennan¹, Bill Bowden¹, Mike Bolland¹, Zed Rengel^{2 …}

Crop Updates 2000 - Lupins, Bill O'Neill, Geoff Thomas, Mark Sweetinham, Kedar Adhikari, Nick Galwey, Miles Dracup, Bob French, Debbie Thackray, Jenny Hawkes, Roger Jones, Françoise Berlandier, Yvonne Cheng, Lisa Smith, Chris Gazey, Michael O'Connell, Peter Carlton, John R. Peirce, Brad J. Rayner, Terry Piper, Peter Newman, Cameron Weeks, Mohammad Amjad, Glen Riethmuller, Paul Blackwell, Jairo A. Palta, Neil C. Turner, Robert J. French, Tim Setter

Crop Updates

This session covers nineteen papers from different authors:

1.1999 Lupin Highlights, Bill O’Neill, LUPIN PRODUCTIVITY IMPROVEMENTS AND INDUSTRY DEVELOPMENT

LUPIN ANTHRACNOSE

2. Anthracnose – 1999/2000, Geoff Thomas and Mark Sweetingham, Agriculture Western Australia

LUPIN BREEDING AND AGRONOMY

3. The genetic control of mildly restricted branching in narrow-leafed lupin (Lupinus augustifolius L), Kedar Adhikari^1,3, Nick Galwey^1,3 and Miles Dracup^2,3 1Plant Sciences, University of Western Australia 2Agriculture Western Australia ³Cooperative Research Centre for Legumes in Mediterranean Agriculture, University of Western Australia

4. Genotype x time of sowing interaction in lupins – Mingenew, Bob French, …

Crop Updates 2000 - Cereals Part 2, Debbie Thackray, Jenny Hawkins, Roger Jones, Dominie Wright, Peter Carlton, Jat Bhathal, Robert Loughman, K. Jayasena, J. Majewski, S. Kelly, G. Holloway, N, Venn, D. Diepeveen, Brenda Shackley, Darshan Sharma, Wal Anderson, Mohammad Amjad, Vanessa Dooley, Peter Burgess, Ashley Bacon, Frances Hoyle, Keith Devenish, Mathew Appelbee, Mohommed Hamza, Steven Mccoy, Steven Penny

Crop Updates

This session covers twenty papers from different authors:

DISEASE

1. Forecasting aphid and virus risk in cereals, Debbie Thackray, Jenny Hawkes and Roger Jones, Agriculture Western Australia and Centre for Legumes in Mediterranean Agriculture

2. Cereal Diagnostics, Dominie Wright, Agriculture Western Australia

3. The economic returns from spraying for leaf rust in the central wheatbelt in 1999, Peter Carlton, Trials Coordinator, Elders Limited

4. Impact and Management of Yellow Spot and Leaf Rust in the Northern Agricultural Region, Jat Bhathal and Robert Loughman, Agriculture Western Australia

5. Leaf disease management in wheat and barley in the southern …

Evaluation Of Proposed Amended Names Of Several Pseudomonads And Xanthomonads And Recommendations, N. W. Schaad, A. K. Vidaver, G. H. Lacy, K. Rudolph, J. B. Jones

Department of Plant Pathology: Faculty Publications

In 1980, over 90% of all plant-pathogenic pseudomonads and xanthomonads were lumped into Pseudomonas syringae and Xanthomonas campestris, respectively, as pathovars. The term “pathovar” was created to preserve the name of plant pathogens, but has no official standing in nomenclature. Proposals to elevate and rename several pathovars of the genera Pseudomonas and Xanthomonas to the rank of species has caused great confusion in the literature. We believe the following changes have merit and expect to adopt them for publication in a future American Phytopathological Society Laboratory Guide for Identification of Plant Pathogenic Bacteria. Upon review of published data …

Bulletin 4406a - Fungal Diseases Of Canola In Western Australia, Martin Barbetti, Ravjit Khangura

Bulletins 4000 -

GRDC - Grains Research & Development Corporation.

There has been dramatic growth in the canola industry in Western Australia, from 35,000 hectares in 1993 to 920,000 hectares in 1999. Along with this expansion in the area sown the incidence and severity of various fungal diseases have also increased, especially blackleg. This Bulletin describes the most important and most prevalent fungal diseases of canola in Western Australia.

An Efficient Wheat Transformation Procedure: Transformed Calli With Long-Term Morphogenic Potential For Plant Regeneration, Lingyu Zhang, J.J. Rybczynski, W.G. Langenberg, Amitava Mitra, Roy C. French

Department of Plant Pathology: Faculty Publications

A method for producing large numbers of transgenic wheat plants has been developed. With this approach, an average of 9.7% of immature embryo explants were transformed and generated multiple self-fertile, independently transformed plants. No untransformed plants, or escapes, were regenerated. This transformation procedure uses morphogenic calli derived from scutellum tissue of immature embryos of Triticum aestivum cv. Bobwhite co-bombarded with separate plasmids carrying a selectable marker gene (bar) and a gene of interest, respectively. Transformed wheat calli with a vigorous growth phenotype were obtained by extended culture on media containing 5.0 mg/l bialaphos. These calli retained morphogenic potential …

The Pseudomonas Syringae Hrp Pathogenicity Island Has A Tripartite Mosaic Structure Composed Of A Cluster Of Type Iii Secretion Genes Bounded By Exchangeable Effector And Conserved Effector Loci That Contribute To Parasitic Fitness And Pathogenicity In Plants, James R. Alfano, Amy O. Charkowski, Wen-Ling Deng, Jorge L. Badel, Tanja Petnicki- Ocwieja, Karin Van Dijk, Alan Collmer

Center for Plant Science Innovation: Faculty Publications

The plant pathogenic bacterium Pseudomonas syringae is divided into pathovars differing in host specificity, with P. syringae pv. syringae (Psy) and P. syringae pv. tomato (Pto) representing particularly divergent pathovars. P. syringae hrp/hrc genes encode a type III protein secretion system that appears to translocate Avr and Hop effector proteins into plant cells. DNA sequence analysis of the hrp/hrc regions in Psy 61, Psy B728a, and Pto DC3000 has revealed a Hrp pathogenicity island (Pai) with a tripartite mosaic structure. The hrp/hrc gene cluster is conserved in all three strains and is flanked by a unique exchangeable …

Basic Biotechnology, Jennifer Flak, Julie Albrecht

Plant and Soil Sciences eLibrary

An introduction to traditional cross-breeding and genetic engineering of plants, and to biotechnology.

Objectives - Basic Biotechnology

After completing Nutrition Basic Biotechnology, participants should be able to:

• Describe one similarity between traditional cross-breeding and genetic engineering of plants.
• Give two limitations that are encountered with traditional cross-breeding of plants.
• Explain why genetic engineering is not limited in the same way as traditional cross-breeding.
• Define biotechnology in broad terms.
• List three plant applications of biotechnology.
• List the three areas of nutritional profiles that have been improved with biotechnology.

Modules:

• Lesson home
• Objectives - Basic Biotechnology
• Historical Uses of Biotechnology
• Basic Understanding …

Sistem Diagnosis Penyakit Tanaman Padi (Pakar Padi), Jin Gee Tee

Student Works (2000-2009)

Beras adalah makanan utama rakyat Malaysia. Banyak kajian dan penyelidikan dibuat untuk meningkatkan hasil tanaman padi. Di antaranya termasuklah mengkaji cara-cara kawalan serangga perosak dan kerja-kerja diagnosis penyakit tanaman padi. Maklumat-maklumat daripada hasil kajian harus disimpan dengan baik supaya kerja diagnosis dapat dijalankan dengan lebih lancar. Memandangkan keperluan ini, satu sistem berkomputeran yang menyimpan data data mengenai tanaman padi adalah penting dan dijangka akan memberi bantuan dalam pengurusan dan kerja-kerja diagnosis. Ini telah membawa kepada idea untuk membangunkan satu sistem diagnosis penyakit bagi tanaman padi. Sistem Diagnosis Penyakit Tanaman Padi, diberikan nama Pakar Padi adalah satu sistem berpangkalan komputer yang …

Optical Transmittance Of A Rice Leaf Via Ray Tracing, Stephen Nicoletti, Alois (Al) J. Adams

Journal of the Arkansas Academy of Science

Optical reflectance from a plant leaf increases in response to stress and disease. Previous studies at the University of Arkansas at Little Rock found that, while the reflectance from a rice leaf increased with increased salinity, reflectance changes could not be used to differentiate one stress or disease from another. The objective of this study is to characterize the angular distribution of optical transmittance for a healthy rice leaf using a ray tracing technique and assuming a three-media optical model. The ultimate goal is to relate this distribution to specific plant pathologies. Three rays are traced through the cross section …

The Role Of Chitinase Production By Stenotrophomonas Maltophilia Strain C3 In Biological Control Of Bipolaris Sorokiniana, Zhongge Zhang, Gary Y. Yuen

Department of Plant Pathology: Faculty Publications

The role of chitinase production by Stenotrophomonas maltophilia strain C3 in biological control of leaf spot on tall fescue (Festuca arundinacea), caused by Bipolaris sorokiniana, was investigated in vitro and in vivo. The filtrate of a broth culture of C3, with chitin as the carbon source, was separated into fractions. A high molecular-weight fraction (>8 kDa) was chitinolytic and more inhibitory than a low-molecularweight, nonchitinolytic fraction to conidial germination and hyphal growth by B. sorokiniana and to leaf spot development. A protein fraction derived by ammonium sulfate precipitation and a chitinase fraction purified by chitin affinity …

Soybean Cyst Nematode Reproduction In The North Central United States, J. Wang, P. A. Donald, T. L. Niblack, G. W. Bird, J. Faghihi, J. M. Ferris, C. Grau, D. J. Jardine, P. E. Lipps, A. E. Macguidwin, H. Melakeberhan, G. R. Noel, P. Pierson, P. M. Riedel, P. R. Sellers, W. C. Stienstra, T. C. Todd, G. L. Tylka, T. A. Wheeler, D. S. Wysong

Department of Plant Pathology: Faculty Publications

An experiment was conducted in Heterodera glycines–infested fields in 40 north central U.S. environments (21 sites in 1994 and 19 sites in 1995) to assess reproduction of this nematode. Two resistant and two susceptible soybean cultivars from each of the maturity groups (MG) I through IV were grown at each site in 6.1 m by 4 row plots. Soil samples were collected from each plot at planting and harvest and processed at Iowa State University to determine H. glycines initial (Pi) and final (Pf) population densities as eggs per 100 cm3 of soil. Overall, reproduction (Pf/Pi) of H. glycines …

Phylogeny Of Calostoma, The Gelatinous-Stalked Puffball, Based On Nuclear And Mitochondrial Ribosomal Dna Sequences, Brandi D. Hughey, Gerard C. Adams, Tom D. Bruns, David S. Hibbett

Department of Plant Pathology: Faculty Publications

Nucleotide sequence of the nuclear small and large subunit and the mitochondrial small and large ribosomal genes of Calostoma were used to investigate evolutionary relationships with other Basidiomycetes. In separate analyses with each gene, Calostoma was placed within the Boletales and outside the clades containing most gilled mushrooms, puffballs, stalked puffballs, earthstars, stinkhorns, and nonboletalean Gasteromycetes. This contradicted previous taxonomic hypotheses. Calostoma was most closely related to Gyroporus, Pisolithus, and Scleroderma based on maximum parsimony and maximum likelihood analysis of the mitochondrial large ribosomal gene database, which contained several representatives of most genera of the Boletales. In three …

Fully Biologically Active In Vitro Transcripts Of The Eriophyid Mite-Transmitted Wheat Streak Mosaic Tritimovirus, Il-Ryong Choi, Roy C. French, Gary L. Hein, Drake C. Stenger

Department of Plant Pathology: Faculty Publications

Infectious RNA of wheat streak mosaic virus (WSMV) has been produced using a full-length cDNA clone as a template for in vitro transcription with SP6 RNA polymerase. Infectivity was dependent on the use of template plasmid DNA that had not undergone spontaneous rearrangement during amplification in Escherichia coli. The presence of WSMV in systemically infected wheat plants inoculated with in vitro transcripts was confirmed by reverse-transcription polymerase chain reaction of the WSMV P3 gene and by accumulation of WSMV coat protein as detected by immunoblotting. Maintenance of the full-length WSMV cDNA in the high copy number plasmid pUC18 was problematic …

Biological Control Of Bipolaris Sorokiniana On Tall Fescue By Stenotrophomonas Maltophilia Strain C3, Z. Zhang, G. Y. Yuen

Department of Plant Pathology: Faculty Publications

Stenotrophomonas maltophilia strain C3 was evaluated for control of leaf spot on tall fescue (Festuca arundinacea) caused by Bipolaris sorokiniana. In growth chamber experiments, C3 inhibited conidial germination on leaf surfaces and reduced lesion frequency and percent diseased leaf area compared with nontreated controls. The amount of leaf spot suppression was related to the C3 dose applied. The highest dose tested, 10⁹ CFU/ml, prevented nearly all B. sorokiniana conidia from germinating on treated leaf surfaces and provided nearly complete suppression of lesion development. When colloidal chitin was added to C3 cell suspensions of 10⁷ or …

The Avr (Effector) Proteins Hrma (Hoppsya) And Avrpto Are Secreted In Culture From Pseudomonas Syringae Pathovars Via The Hrp (Type Iii) Protein Secretion System In A Temperature- And Ph-Sensitive Manner, Karin V. Van Dijk, Derrick E. Fouts, Amos H. Rehm, Angela R. Hill, Alan Collmer, James R. Alfano

Center for Plant Science Innovation: Faculty Publications

We present here data showing that the Avr proteins HrmA and AvrPto are secreted in culture via the native Hrp pathways from Pseudomonas syringae pathovars that produce these proteins. Moreover, their secretion is strongly affected by the temperature and pH of the culture medium. Both HrmA and AvrPto were secreted at their highest amounts when the temperature was between 18 and 22°C and when the culture medium was pH 6.0. In contrast, temperature did not affect the secretion of HrpZ. pH did affect HrpZ secretion, but not as strongly as it affected the secretion of HrmA. This finding suggests that …

Agriculture Western Australia's Centre For Cropping Systems - Northam, Agriculture Western Australia

Grain and other field crops published reports

Agriculture Western Australia's Centre for Cropping Systems in York Road, Northam, was established as a centre of excellence for research, development and extension into cropping systems.

Its role is to stimulate the contribution of ideas from individuals, groups and organisations with an interest in research, development, and extension relating to innovative, profitable and sustainable crop-based farming systems.

The Centre for Cropping Systems is part of a regional network with strong links to Agriculture Western Australia's Crop Improvement Institute based at South Perth, the Dryland Research Institute at Merredin and the Avondale Research Fann at Beverley. It also links with universities …

Dnak And The Heat Stress Response Of Pseudomonas Syringae Pv. Glycinea, Lisa M. W. Keith, James E. Partridge, Carol L. Bender

Department of Plant Pathology: Faculty Publications

The dnaK gene from Pseudomonas syringae pv. glycinea PG4180 was cloned and sequenced. The dnaK coding region was 1,917 bp and contained a putative O³² heat shock promoter 86 bp upstream of the translational start site. grpE, another heat shock gene, was found immediately upstream of the putative dnaK promoter. The predicted amino acid sequence of dnaK showed relatedness to the ATPase and substrate binding domains commonly found in heat shock proteins, as well as the highly conserved signature sequence motifs belonging to the Hsp70 protein family. Furthermore, the PG4180 dnaK gene complemented an Escherichia coli dnaK mutant …

Morphogenesis Is Coordinated With Nuclear Division In Germinating Aspergillus Nidulans Conidiospores, Steven D. Harris

Department of Plant Pathology: Faculty Publications

Germinating Aspergillus nidulans conidiospores switch to polarized apical growth following an initial period of isotropic expansion. At the same time, they re-enter the nuclear division cycle. The relationship between spore polarization and nuclear division was investigated by testing the effect of cell cycle inhibitors and temperature-sensitive cell cycle mutations on spore morphogenesis. On rich media, it was found that spore polarization is delayed if completion of the first mitosis is blocked. The observed delay may be dependent upon the activity of the mitosis-promoting NIMA kinase. An additional mechanism appears to prevent polarization as the spore progresses through its first S …

An Engineered Closterovirus Rna Replicon And Analysis Of Heterologous Terminal Sequences For Replication, Satyanarayana Tatineni, Siddarame Gowda, V. P. Boyko, Maria R. Albiach-Marti, Munir Mawassi, J. Navas-Castillo, Alexander V. Karasev, V. Dolja, Mark E. Hilf, D. J. Lewandowski, P. Moreno, Moshe Bar-Joseph, S. M. Garnsey, William O. Dawson

Department of Plant Pathology: Faculty Publications

Citrus tristeza virus (CTV) populations in citrus trees are unusually complex mixtures of viral genotypes and defective RNAs developed during the long-term vegetative propagation of the virus and by additional mixing by aphid transmission. The viral replication process allows the maintenance of minor amounts of disparate genotypes and defective RNAs in these populations. CTV is a member of the Closteroviridae possessing a positive-stranded RNA genome of ≈20 kilobases that expresses the replicase-associated genes as an ≈400-kDa polyprotein and the remaining 10 3' genes through subgenomic mRNAs. A full-length cDNA clone of CTV was generated from which RNA transcripts capable of …

Cereal Rust Diseases And Their Management, 1999, Rob Dickie, Rob Loughman, Jat Bhathal

Technical Bulletins

• Wheat leaf rust (Puccinia recondita f.sp. tritici) is specific to wheat and triticale. A single pathotype (designated 104-1,2,3,(6),(7),11) has dominated in W.A. since 1990. Wheat leaf rust regularly survives the non-cropping summer in varying quantities, usually sufficient to occur at least to a limited extent (particularly in southern regions) each year. The disease develops rapidly between 15 and 22°C when moisture (including dew) is non-limiting. The highest yield increase attributed directly to control of leaf rust in W.A. is 37 per cent. However the disease is synergistically damaging in combination with septoria leaf blotches. In Esperance in …