Life Sciences Commons^™

Verticillium Wilt Of Woody Ornamentals, John Hartman

Agriculture and Natural Resources Publications

Verticillium wilt is a common problem on maple, catalpa, golden-rain tree, redbud, and tulip poplar trees in Kentucky. In addition, this disease occurs on ash, azalea, barberry, brambles, buckeye, cherry and other stone fruits, Kentucky coffee tree, cork tree, currant, elm, honeysuckle, horse chestnut, lilac, black locust, magnolia, nandina, Russian olive, osage orange, Japanese pagoda tree, persimmon, privet, rose, sassafras, serviceberry, smoke tree, sumac, tree-of-heaven, tupelo, viburnum, weigela, and yellowwood. More than 300 other woody and herbaceous plant species are known to be susceptible to Verticillium wilt.

Partial Characterization Of Bacteriophages Of Pseudomonas Syringae Pv.Tomato, Scott M. Minor, Russell O. Nordeen, Chad E. Paschall

Journal of the Arkansas Academy of Science

No abstract provided.

The Complete Nucleotide Sequence And Genome Organization Of The M Rna Segment Of Peanut Bud Necrosis Tospovirus And Comparison With Other Tospoviruses, Satyanarayana Tatineni, S. E. Mitchell, D. V. R. Reddy, S. Kresovich, R. Jarret, R. A. Naidu, S. Gowda, J. W. Demski

Department of Plant Pathology: Faculty Publications

The M RNA of peanut bud necrosis virus (PBNV; synonym groundnut bud necrosis virus) is 4801 nucleotides in length. It comprised two ORFs in an ambisense organization and terminal inverted repeats. The 3' large ORF (3363 nucleotides in the virus-complementary strand) encoded a protein with a predicted size of 127.2 kDa which was identified as the glycoprotein precursor (GP) of the G1 and G2 glycoproteins. A comparison of the deduced amino acid sequence of GP revealed 37 % identity and 58-59% similarity with that of tomato spotted wilt virus (TSWV, serogroup I) and impatiens necrotic spot virus (INSV, serogroup III), …

Peanut Bud Necrosis Virus: Purification Of Nucleocapsids And Sequence Homology Of Nucleocapsid Protein And Glycoprotein Precursor With Other Tospoviruses, Satyanarayana Tatineni, S. E. Mitchell, D. V. R. Reddy, S. Brown, S. Kresovich, R. Jarret, S. Gowda, R. A. Naidu, J. W. Demski

Department of Plant Pathology: Faculty Publications

A procedure for the purification of peanut bud necrosis virus (PBNV) nucleocapsids was developed. Virus particles were treated with nonionic detergent to disrupt the envelope membrane and free nucleocapsids were separated. into three lightscattering zones after sucrose gradient centrifogation. Nucleocapsids from the top zone contained S RNA and traces ofM RNA; whereas, nucleoplasids from the middle zone contained M RNA with detectable levels of S RNA and those from the bottom zone contained L RNA with traces of M and S RNAs. Clones from a cDNA library made from the purified PBNV Sand M RNAs were characterized and sequenced. Comparison …

Diagnosis And Resistance Breeding Of Peanut Bud Necrosis Virus, D. V. R. Reddy, Satyanarayana Tatineni, S. L. Dwivedi, A. S. Ratna, A. A. M. Buiel, G. V. Ranga Rao, S. N. Nigam, R. A. Naidu, H. T. Hsu, J. W. Demski

Department of Plant Pathology: Faculty Publications

The occu!fence of peanut bud necrosis (PBN) disease in India was first reported in 1968. The high incidence ofPBN disease during the 1960s coincided with largescale imports of the peanut cultivars Asiria Mwitundae and Spanish Improved, both of which are highly susceptible to PBN. Since then, a number of reports have been published in India describing bud necrosis under at least seven different names (Reddy 1988). Crop losses due to PBN have been estimated at USD89 million per year in India during 1976-1986. The disease is also currently recognized as economically important in Nepal (Sharma 1996), in Sri Lanka, and …

Fumonisins And Alternaria Alternata Lycopersici Toxins: Sphinganine Analog Mycotoxins Induce Apoptosis In Monkey Kidney Cells, Hong Wang, Clinton Jones, Janice Caiacci-Zanella, Todd Holt, David G. Gilchrist, Martin B. Dickman

Department of Plant Pathology: Faculty Publications

Fusarium moniliforme toxins (fumonisins) and Alternaria alternata lycopersici (AAL) toxins are members of a new class of sphinganine analog mycotoxins that occur widely in the food chain. These mycotoxins represent a serious threat to human and animal health, inducing both cell death and neoplastic events in mammals. The mechanisms by which this family of chemical congeners induce changes in cell homeostasis were investigated in African green monkey kidney cells (CV-1) by assessing the appearance of apoptosis, cell cycle regulation, and putative components of signal transduction pathways involved in apoptosis. Structurally, these mycotoxins resemble the sphingoid bases, sphingosine and sphinganine, that …

A Mammalian 2-5a System Functions As An Antiviral Pathway In Transgenic Plants, Amitava Mitra, Dan W. Higgins, William G. Langenberg, Huiqin Nie, Dibyendu N. Sengupta, Robert H. Silverman

Department of Plant Pathology: Faculty Publications

Resistance to virus infections in higher vertebrates is mediated in part through catalysis of RNA decay by the interferon-regulated 2-5A system. A functional 2-5A system requires two enzymes, a 2-5A synthetase that produces 5"phosphorylated, 2',5'-linked oligoadenylates (2-5A) in response to double-stranded RNA, and the 2-5A-dependent RNase L. We have coexpressed these human enzymes in transgenic tobacco plants by using a single plasmid containing the cDNAs for both human RNase L and a low molecular weight form of human 2-5A synthetase under control of different, constitutive promoters. Expression of the human cDNAs in the transgenic plants was demonstrated from Northern blots, …

Molecular Diagnostics Of Three Diabrotica (Coleoptera: Chrysomelidae) Pest Species, Allen L. Szalanski, Thomas O. Powers

Department of Plant Pathology: Faculty Publications

A 257 bp region of the mitochondrial ND4 gene was analyzed for genetic variation in three species of corn rootworm, southern corn rootworm (Diabrotica undecim punctata howardi Barber, SCR), northern corn rootworm (D. barberi Smith and Lawrence, NCR), and western corn rootworm (D. virgifera virgifera LeConte, WCR). Nucleotide sequencing revealed 26 polymorphic sites. Genetic distances averaged 8% for all pair-wise comparisons among the three species. Restriction maps were constructed from sequence data and compared to potential species specific restriction sites. Polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) revealed three restriction enzymes (Alu I, Apo I …

United States Patent, Number: 5,466,788: Subgenomic Promoter, Paul G. Ahlquist, Roy C. French

Department of Plant Pathology: Faculty Publications

A subgenomic promoter of a positive strand RNA virus is disclosed which directs the amplified expression of a structural gene in plant tissue. The core region and an upstream activating domain of the subgenomic promoter are identified. This promoter can be utilized in a modified virus, or in an appropriate engineered recombinant DNA derivative, which may be chromosomally integrated or maintained as an episome in transformed cells.

Research On Plant Disease And Pest Management Is Essential To Sustainable Agriculture, R. James Cook, Clifford J. Gabriel, Arthur Kelman, Sue Tolin, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

In the United States, a country with food in great abundance, it is difficult to realize that, were it not for the current level of plant disease and pest management, most human resources would be needed to obtain enough food and other plant and animal products merely to survive. Instead, there are surpluses, markets for many agricultural products are depressed, and funds available for research on plant disease and pest management-and for agricultural research generally-have plateaued or are declining. Why does the United States need more research on plant disease and pest management? Because the health and productivity of the …

Research On Plant Disease And Pest Management Is Essential To Sustainable Agriculture, R. James Cook, Clifford J. Gabriel, Arthur Kelman, S. Tolin, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

In the United States, a country with food in great abundance, it is difficult to realize that, were it not for the current level of plant disease and pest management, most human resources would be needed to obtain enough food and other plant and animal products merely to survive. Instead, there are surpluses, markets for many agricultural products are depressed, and funds available for research on plant disease and pest management-and for agricultural research generally-have plateaud or are declining.

Why does the United States need more research on plant disease and pest management? Because the health and productivity of the …

Proceedings Of The 22nd Annual Meeting, Southern Soybean Disease Workers (February 20-22, 1995, St. Louis, Missouri), John Rupe, Brian M. Anderson, Robert P. Mulrooney, Gabe Sciumbato, Glenn G. Hammes

Southern Soybean Disease Workers: Conference Proceedings

Contents

Business session

Soybean Disease Loss Estimate for the Southern United States during 1994. JA Wrather

Treasurer report. GG Hammes

SSDW Committee Chairmen for 1994-1995

Graduate student papers

Host preference of Rotylenchulus reniformis for weed species common to Louisiana soybean. CH Carter, EC McGawley, and JS Russin

Development of an immunoassay for Heterodera glycines eggs. MJ Kennedy, JE Schoelz, TL Niblack, PA Donald

Effects of delayed planting and host susceptibility on colonization of soybean by Calonectria crotalariae and development of red crown rot. PU Kuruppu, JS Russin, and EC McGawley

Effects of long-term corn/soybean rotation on pathogenicity of Pythium populations …

Coming To Grips With Eradu-Patch Of Lupins, Bill Macleod, Mark Sweetingham

Journal of the Department of Agriculture, Western Australia, Series 4

Investigations by Bill MacLoud and Mark Sweetingham have confirmed that Eradu-patch of lupins is caused by apreviously undescribed fungal pathogen,\.

They have developed strategies to minimise the spread of patches but choices are limited for control in lupin crops

Cucumber Mosiac Virus In Lupins, Annette Bwye, Roger Jones, Wayne Proudlove

Journal of the Department of Agriculture, Western Australia, Series 4

Cucumber mosaic virus is a threat to lupin crops from Geraldton to Esperance, particularly to those growing in areas receiving more than 400 mm average annual rainfall. The disease markedly decreases grain yield in narrow-leafed and yellow lupins but doesnot infect albus or sandplain lupins. Worldwide , after bean yellow mosaic virus, cucumber mosaic virus is the second most important virus affecting lupins. Annette Bwye, Roger Jones and Wayne Proudlove outline the symptoms, spread and management of this serious disease.

Pulses : Profitable New Crops For The Wheatbelt, Kadambot Siddique, Stephen Loss, Ian Pritchard

Journal of the Department of Agriculture, Western Australia, Series 4

Narrow-leafed lupins have beeb produced on sandy acid soils throughout the wheatbelt for more than two decades. However, the wheatbelt contains large areas ofsoilsnot suited to narrow-leafed lupins. For several years reasearchers have been examining alternatives to narrow-leafed lupins for these soils.

Kadambot Siddique, Stephen Loss and Ian Prichard look at production of these new grain legumes, known as pulses.

Bulletin 4294 - Virus Diseases Of Lupins, Roger Jones

Bulletins 4000 -

Two virus diseases pose a serious threat to lupins. These are caused by cucumber mosaic virus (CMV), which induces diseases in narrow-leafed and yellow lupins, and bean yellow mosaic virus (BYMV), which infects all types of cultivated lupins. The effects of the viruses on lupin plants range from subtle colour changes and leaf distortion to leaf shedding, stunting and death. Seed production is decreased or prevented. There is no cure, but lupin crops can be managed to minimise both virus spread and its persistence from year to year.

CMV and BYMV occur within all tissues in the plant, but do …

Gray Leaf Spot Of Corn, Paul Vincelli, Donald E. Hershman

Agriculture and Natural Resources Publications

Gray leaf spot of corn, while of little consequence in the US before 1970, has become a major concern to many corn producers in recent years. Serious outbreaks of the disease first occurred in the early to mid 1970s in low-lying areas in the mountainous regions of Kentucky, North Carolina, Tennessee and Virginia. Since this time, the disease has spread to most corn-producing areas of western Kentucky and parts of Delaware, Illinois, Indiana, Iowa, Maryland, Missouri, Ohio, Pennsylvania and west Tennessee.

Biosystematics And Diversification In The Genus Striga Lour. (Scrophulariaceae) In Africa, Kamal-Eldin Ibrahim Mohamed

Biological Sciences Theses & Dissertations

Of the 34 taxa of Striga (29 species) that occur in Africa, 25 are endemic. Species diversity differs from region to region. The subtropical zone has 74% of the taxa including 41% endemics. Within this region, the West African part (from Senegal to eastern Nigeria) has 62% of the total taxa including 24% endemics. South of the equator the number of taxa is 56% of the total with 21% endemics, a proportion slightly less than that for West Africa. I recognize 29 species based on extensive herbarium and field studies. A new species from Angola is described. Striga yemenica previously …

Proceedings Of The 21st Annual Meeting, Southern Soybean Disease Workers (March 6-8, 1994, Tulsa, Oklahoma), Glenn Bowers, John Rupe, Brian M. Anderson, Gabe Sciumbato, Glenn G. Hammes

Southern Soybean Disease Workers: Conference Proceedings

Contents

1993-94 SSDW Committee Chairs

1993-94 SSDW Officers

Graduate student competition

Resistance of Soybean Cultivars in Maturity Group IV-VIII to Rotylenchulus reniformis. JJ Cornelius and GW Lawrence

Evaluation of Susceptibility of Soybean to Red Crown Rot caused by Calonectria crotalariae in the Field. KD Kim, JS Russin, and JP Snow

Contributed papers

Soybean Disease Loss Estimate for the Southern United States During 1993, Table 1. Estimated percent Joss of soybean yields in 1993 to disease, Table 2. Estimated reduction of soybean yields in 1993 to disease, and Table 3. Southern states soybean disease loss estimate total in bushels and …

Fundamental Principles Of Plant Pathology For Agricultural Producers, Paul C. Vincelli

Agriculture and Natural Resources Publications

All crop plants produced in Kentucky have the potential to become diseased under certain conditions. Diseases of crops can affect yield and/or quality of the harvested commodity. This can impact profitability and increase the risks of farming.

A plant is diseased when it is affected by some agent that interferes with its normal development. Some disorders are caused by noninfectious factors, such as temperature extremes or nutrient deficiencies. However, this publication focuses on diseases caused by infectious microorganisms.

Diseased plants exhibit a variety of symptoms. These can include stunting, yellowing, wilting, twisting, reddening, browning, blighting, root rot, fruit rot, …

Meloidogyne Javanica Parasitic On Peanut, E. K. Tomaszewski, M. A. M. Khalil, A. A. El-Deeb, Thomas O. Powers, J. L. Starr

Department of Plant Pathology: Faculty Publications

Peanut fields in four governorates of Egypt were surveyed to identify species of Meloidogyne present. Fourteen populations obtained from peanut roots were all identified as M. javanica based on perineal patterns, stylet and body lengths of second-stage juveniles, esterase phenotypes, and restriction fragment length polymorphisms of mtDNA. Three of 14 populations, all from contiguous fields in the Behara governorate, had individuals with a unique two-isozyme esterase phenotype. All populations of M. javanica tested on peanut had levels of reproduction on the M. arenaria-susceptible peanut cultivar Florunner that were not different from M. arenaria (P = 0.05), and had lower …

Identification And Characterization Of Aspergillus Nidulans Mutants Defective In Cytokinesis, Steven D. Harris, Jennifer L. Morrell, John E. Hamer

Department of Plant Pathology: Faculty Publications

Filamentous fungi undergo cytokinesis by forming crosswalls termed septa. Here, we describe the genetic and physiological controls governing septation in Aspergillus nidulans. Germinating conidia do not form septa until the completion of their third nuclear division. The first septum is invariantly positioned at the basal end of the germ tube. Block-and-release experiments of nuclear division with benomyl or hydroxyurea, and analysis of various nuclear division mutants demonstrated that septum formation is dependent upon the third mitotic division. Block-and-releasee xperiments with cytochalasin A and the localization of actin in germlings by indirect immunofluorescence showed that actin participated in septum formation. In …

Biological Control Of Doublegee : Israeli Weevil Could Help Fight Doublegee, John Scott, Paul Yeoh

Journal of the Department of Agriculture, Western Australia, Series 4

Since its deliberate introduction from South Africa as a salad vegetable in 1830 the doublegee has spread to become a major weed throughout much of Australia.

It is one of the most serious weeds of crops and pastures in Western Australia, smothering other more useful plants while young, and troubling both humans and animals with its sharp spiny seeds when mature.

Using biological control techniques, scientists are now attacking it and related docks in three ways - with an aphid, a weevil and a fungus.

Within a few years it is hoped that while still present, the doublegee will be …

Biological Control Of Doublegee : Doublegee Decline And The Dock Aphid, John Scott, Francoise Berlandier, Kristy Hollis

Journal of the Department of Agriculture, Western Australia, Series 4

Since 1990 farmers in the Western Australian wheatbelt have been reporting doublegee plants that appear to be diseased, stunted and producing poorly formed fruit (the spiny casing around the single doublegee seed). Often no obvious cause of this decline in plant health is apparent. Experiments carried out in 1990 showed that an aphid, which feeds hidden in the growing tips of doublegee stems and in young distorted leaves, is the most likely cause. This North American aphid, the dock aphid (Brachycaudus rumexicolens), arrived in WA in 1987. It appears to only feed on docks, doublegees and related plants and is …

Developing Improved Varieties Of Subterranean Clover, Phil Nichols, Bill Collins, Dennis Gillespie, Martin Barbetti

Journal of the Department of Agriculture, Western Australia, Series 4

Subterranean clover is widely recognised as the most important pasture legume species in southern Australia, having been sown over about 20 million hectares.

Together with superphosphate and trace elements, it has been a key factor in improving and maintaining soil fertility, and has resulted in dramatic increases in crop, livestock and wool production.

While the value of subterranean clover is well established, it does have some shortcomings.

Many varieties grown today are not sufficiently adapted to the environments and management systems in use. Others lack sufficient pest and disease resistance.

Improved subterranean clovers are being bred with better adaptation and …

Merging Conservation With Production In Remnant Bush, Anne Morgan, Alison Fuss

Journal of the Department of Agriculture, Western Australia, Series 4

Exports of cutflowers and foliage from Western Australia are now worth about $17 million a year. A third of this is picked from the bush, either on Crown Land or areas of remnant bush on private property. While the industry's future lies in cultivation, bush picking is likely to remain important for some years. This can provide both extra income for farmers and benefit the environment - as long as care is taken

Characterization Of Heterorhabditis Isolates By Pcr Amplification Of Segments Of Mtdna And Rdna Genes, Susan A. Joyce, Ann M. Burnell, Thomas O. Powers

Department of Plant Pathology: Faculty Publications

Restriction digests of amplified DNA from the mitochondrial genome and the nuclear ribosomal internally transcribed spacer region have been evaluated as genetic markers for species groups in Heterorhabditis. Six RFLP profiles have been identified. These profiles supported groupings determined by cross-breeding studies and were in agreement with less definitive groupings based on other biochemical and molecular methods. Digestion patterns of both amplification products provided strong evidence for the recognition of species groups, which include Irish, NW European, tropical, and a H. bacteriophora complex. The H. bacteriophora complex could be further resolved into three genotypes represented by H. zealandica, …

Biological Control Of Doublegee : Fungi May Be Another Weapon, Roger Shivas, John Scott

Journal of the Department of Agriculture, Western Australia, Series 4

A fungus has been assessed both in Australia and South Africa since 1989 for its potential to control doublegee.

Under optimal environmental conditions it causes a severe stem blight which ultimately kills the plant. It also infects seeds, and caused up to 30 per cent mortality at a field site near Badgingarra.

Hopes to develop the fungus as a mycoherbicide (fungal killer of plants) have had to be dropped because it produces a potent toxin but it is still contributing to control in the field.

Kentucky Plant Disease Management Guide For Soybeans, Donald E. Hershman

Agriculture and Natural Resources Publications

This guide contains information on the biology and management of the most important diseases of soybeans in Kentucky. Fundamental information on symptoms, disease cycle, and management is provided. For some diseases, more extensive information on biology and management is also available in other Extension publications. Additional sources of information are listed under individual diseases.

Disease management in soybeans relies heavily on using disease-resistant varieties, when available, and employing sound agronomic practices. It is important to integrate both of these strategies into a comprehensive disease management program. Failure to consider one or the other will compromise the success of your efforts. …

Kentucky Plant Disease Management Guide For Small Grains, Donald E. Hershman, Paul C. Vincelli

Agriculture and Natural Resources Publications

This guide contains information on the biology and management of the most important diseases of small grains (wheat and barley) in Kentucky. Fundamental information on symptoms, disease cycle, and management is provided. For some diseases, more extensive information on biology and management is also available in other Extension publications. Additional sources of information are listed under individual diseases.

Disease management in small grains relies heavily on using disease-resistant varieties and employing sound agronomic practices. It is important to integrate both of these strategies into a comprehensive disease management program. Failure to consider one or the other will compromise the success …