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Plant Pathology

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Alfalfa Latent Virus, A Naturally Occurring Carlavirus In Alfalfa, Yenkateswarlu Veerisetty, Myron K. Brakke Jan 1977

Alfalfa Latent Virus, A Naturally Occurring Carlavirus In Alfalfa, Yenkateswarlu Veerisetty, Myron K. Brakke

Department of Plant Pathology: Faculty Publications

Alfalfa latent virus (ALV), a new member of the carlavirus group, was isolated From alfalfa (Medicago sarivo) clones from rbe University of Nebraska experimental plots and from the Farmers' fields. The pea aphid, Acvrihosiphon pisum, transmitted this virus to M. sativa, Pisum sativum, and Viria faba. but not to Trifolium pratense. It was also sap transmissible to V. faba, V. villoso, and P. sarivum, but was not seed-borne in P. sariuum. In V. Jaba sap ALV was infectious at 65 but not at 70 C in 10 min. or …


Sedimentation Coefficients Of The Virions Of Soil-Borne Wheat Mosaic Virus, Myron K. Brakke Jan 1977

Sedimentation Coefficients Of The Virions Of Soil-Borne Wheat Mosaic Virus, Myron K. Brakke

Department of Plant Pathology: Faculty Publications

The sedimentation coefficient of virion I of soil-borne wheat mosaic virus was estimated to be 219S, the same, within error, as the sedimentation coefficient of the dimer of virion II, estimated to be 218S. The monomer of virion II sedimented at 177S, and was 138 nm long. Another strain of the virus had a virion II (designated lIb) that was 92 nm long and sedimented at 159S. The two virus strains coexist in some fields.


Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer Oct 1976

Report On Wastewater Disposal To Board Of County Commissioners, Clark County Nevada, Clair N. Sawyer

Publications (WR)

This report is concerned with the management of waste-waters and subsurface drainage from the City of Las Vegas and its environs and the BMI complex, all in Clark County, Nevada. The prime objective is to recommend a plan of action which will utilize the natural resources of the area in the least costly manner and still protect Lake Mead for recreational purposes and use as a public water supply, At this writing, conditions in the upper Las Vegas arm of Boulder Basin are quite unsatisfactory for some recreational purposes due to the extensive blooms of algae which develop. Experience at …


Bulletin No 3863 - Plants Which Cause Kimberley Horse Disease, A. L. Payne Apr 1976

Bulletin No 3863 - Plants Which Cause Kimberley Horse Disease, A. L. Payne

Bulletins - 3000 - 3999

Crotalaria crispata and Crotalaria retusa (Rattlepod), two plants responsible for Kimberley horse disease*, are, unfortunately, fairly widespread throughout the Kimberleys. Both species are apparently toxic in all stages of growth.

This bulletin is to assist pastoralists to:-

• Identify the two plants;

• Recognise the type of country and conditions under which they grow; and

• Locate horse paddocks on country where the plants are least likely to occur.


Armyworm Control In Coarse Grain Crops, G D. Rimes Jan 1976

Armyworm Control In Coarse Grain Crops, G D. Rimes

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

Investigations of armyworm infestations carried out in Western Australia during 976 have shown that a complex of three species is involved in the spasmodic outbreaks that may cause damage to course grain crops.

This article looks at the economics of control methods.


Root Rot Of Subterranean Clover In W.A, G C. Macnish, M. J. Barbetti, D. Gillespie, K. Hawley Jan 1976

Root Rot Of Subterranean Clover In W.A, G C. Macnish, M. J. Barbetti, D. Gillespie, K. Hawley

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

Root rot of subterranean clover has occurred sporadically in the south west of Western Australia for a number of years.

In most seasons the disease has affected the clover paddocks of only a few farms, but in 1973 there was widespread pasture decline due to root rot in the South-West and south coastal districts.

At present the most promising approaches for minimising the effect of root rot appear to be the use of cultivation techniques and eventually the use of resistant varieties, or other pasture species.


Lupin Split Seed : A Disorder Of Seed Production In Sweet, Narrow-Leafed Lupins, M W. Perry, J. W. Gartrell Jan 1976

Lupin Split Seed : A Disorder Of Seed Production In Sweet, Narrow-Leafed Lupins, M W. Perry, J. W. Gartrell

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

Commercial seed production from narrow-leafed lupins (Lupinus angustifolius L.) began in Western Australia in 1967, based on the newly-bred low alkaloid cultivar Uniwhite. The release of improved cultivars has led to the crop's wide acceptance and more than 100 000 ha were sown to sweet lupins in 1975.

With the greater area and wider range of soil types devoted to lupins, a developmental abnormality of the seeds, which became known as "split seed", was observed in some situations.


Prospects For Control Of Phytopathogenic Bacteria By Bacteriophages And Bacteriocins, Anne K. Vidaver Jan 1976

Prospects For Control Of Phytopathogenic Bacteria By Bacteriophages And Bacteriocins, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

The last review on bacteriophages and bacteriocins of phytopathogenic bacteria was that of Okabe & Goto (98). All but one (21) of the subsequent reviews (II, 12, 60, 94, 104) have dealt primarily with viruses and bacteriocins of bacteria other than phytopathogens. The most recent microbiological compendia that in­ clude bacteriophages and bacteriocins are of limited value for phytobacteriolo­ gists because the authors generally overlook or ignore such agents (29, 47, 77, 119). However, Adam's classic .book (4), the review by Bradley (II), and the bibliography of Raettig (102) are still of value to phytobacteriologists as are reviews dealing principally …


Leaf Freckles And Wilt Of Corn Incited By Corynebacterium Nebraskense Schuster, Hoff, Mandel, Lazar, 1972, M. L. Schuster May 1975

Leaf Freckles And Wilt Of Corn Incited By Corynebacterium Nebraskense Schuster, Hoff, Mandel, Lazar, 1972, M. L. Schuster

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The new bacterial disease Leaf Freckles and Wilt (LFW) of corn (Zea mays L.) was first observed in 1969 on two farms in southcentral Nebraska. Since then it has spread to other areas in the state. LFW is a serious disease on farms in six Nebraska counties (Clay, Custer, Dawson, Furnas, Hall and Phelps) and has been found in isolated cases in at least 28 other counties. In 1971 LFW was found in a seedcorn field in western Iowa, in 1973 in two Kansas counties, and in 1974 in South Dakota and Colorado. Because of its explosive nature, several …


Survival Factors Of Plant Pathogenic Bacteria, M. L. Schuster, D. P. Coyne Feb 1975

Survival Factors Of Plant Pathogenic Bacteria, M. L. Schuster, D. P. Coyne

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The research works discussed in this review were selected to provide a cross section of the phenomenon of survival of plant pathogenic bacteria.


Influence Of Molecular Weights Of Bacteriophage Φ6 Double-Stranded Ribonucleic Acids On Interferon Induction, W.J. Kleinschmidt, James L. Van Etten, A. K. Vidaver Jul 1974

Influence Of Molecular Weights Of Bacteriophage Φ6 Double-Stranded Ribonucleic Acids On Interferon Induction, W.J. Kleinschmidt, James L. Van Etten, A. K. Vidaver

Department of Plant Pathology: Faculty Publications

The interferon-inducing capabilities of the three molecular segments of bacteriophage φ6 double-stranded ribonucleic acid increased with increasing molecular weight.


Purification And Characterization Of Syringacin 4-A, A Bacteriocin From Pseudomonas Syringae 4-A, William L. Haag, Anne K. Vidaver Jul 1974

Purification And Characterization Of Syringacin 4-A, A Bacteriocin From Pseudomonas Syringae 4-A, William L. Haag, Anne K. Vidaver

Department of Plant Pathology: Faculty Publications

Syringacin 4-A, a bacteriocin produced by Pseudomonas syrinagae 4-A, was obtained by induction with ultraviolet irradiation or mitomycin C. Approximately 1,000-fold purification of the bacteriocin was achieved by manganous chloride precipitation, differential centrifugation, and chromatography on hydroxyapatite columns. The purified syngacin was homogeneous on hydroxyapatite columns and sucrose density gradients; it also sedimented as a single entity in the analytical ultracentrifuge. The buoyant density of purified syringacin in cesium chloride was 1.294 g/ml. The sedimentation coefficient was calculated as 120S, and the diffusion coefficient was 6.49 x 10-8 cm2/s. The molecular weight was calculated as …


Annual ('Wimmera') Ryegrass Toxicity, Geoffrey A. Pearce, O. M. Goss, P. H. Berry, J. L. Wise Jan 1974

Annual ('Wimmera') Ryegrass Toxicity, Geoffrey A. Pearce, O. M. Goss, P. H. Berry, J. L. Wise

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

Because annual ryegrass is one of the most widespread pasture plants in Western Australia, annual ryegrass toxicity is a threat to livestock in many agricultural areas—even though the area now affected is small.

The problem is being intensively studied by the Department of Agriculture and a working group has been set up to investigate potential control measures.

In this article the group reviews the problem and reports progress in its investigations to the end of 1973.


Survival Mechanisms Of Phytopathogenic Bacteria, M. L. Schuster, D. P. Coyne Jan 1974

Survival Mechanisms Of Phytopathogenic Bacteria, M. L. Schuster, D. P. Coyne

Department of Plant Pathology: Faculty Publications

Natural habitats usually do not provide bacteria the continuity of agricultural crops. With continuous culture. perpetuation of pathogen is no problem. Although agricul­ tural practices provide some discontinuity between crops. it is less than that in nature. Uniformity of crop germ plasm also favors inoculum buildup and perhaps perpetuation of the pathogens.


Rna Polymerase Activity Associated With Bacteriophage Φ6, James L. Van Etten, A. K. Vidaver, R. K. Koski, J. S. Semancik Sep 1973

Rna Polymerase Activity Associated With Bacteriophage Φ6, James L. Van Etten, A. K. Vidaver, R. K. Koski, J. S. Semancik

Department of Plant Pathology: Faculty Publications

The Pseudomonas phaseolicola bacteriophage φ6 incorporated labeled UTP into an acid-insoluble precipitate. Incorporation was dependent on the presence of manganese acetate, ATP, GTP, CTP, and a short heat treatment of the phage; the reaction was stimulated by NH,Cl. The substitution of 14C-ATP, -CTP or -GTP for UTP, together with the appropriate unlabeled ribonucleoside triphosphates, disclosed that CMP was incorporated to the greatest extent followed by GMP, UMP, and AMP. Radioactive RNAs formed by the reaction were resistant to RNases A and T1 in high salt but susceptible to these nucleases in low salt. The labeled RNA co-sedimented and …


Bacteriophage Φ6: A Lipid-Containing Virus Of Pseudomonas Phaseolicola, Anne K. Vidaver, R. K. Koski, James L. Van Etten May 1973

Bacteriophage Φ6: A Lipid-Containing Virus Of Pseudomonas Phaseolicola, Anne K. Vidaver, R. K. Koski, James L. Van Etten

Department of Plant Pathology: Faculty Publications

The purification and properties of a lipid-containing bacteriophage, φ 6, are described. The phage contains a lipid envelope which is probably essential for infection. Infectivity of φ 6 was lost in the presence of organic solvents, sodium deoxycholate, and phospholipase A. The fatty acid composition of the phage lipid was similar to that of the Pseudomonas phaseolicola host cells. The phage was composed of about 25% lipid, 13% RNA, and 62% protein. The buoyant density of φ6 was 1.27 g/ml in cesium chloride. The morphology of φ6 was unusual; it had a polyhedral head of about 60 nm surrounded by …


Spray-Graze : The Answer To Weeds In Pastures, Geoffrey A. Pearce Jan 1973

Spray-Graze : The Answer To Weeds In Pastures, Geoffrey A. Pearce

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

W.A. Department of Agriculture research leads to a new technique for weed control in pastures.

The trials which led to the development of the spray-graze technique of weed control started in Western Australia in 1966.

Since 1969, spray-graze has been tried in other States of Australia and is now recognised as the most practical method of controlling many pasture weeds.


Learning To Live With Clover Scorch, A Bokor, D. L. Chatel Jan 1973

Learning To Live With Clover Scorch, A Bokor, D. L. Chatel

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

Recent research has increased our understanding of clover scorch disease in Western Australia.

An economic control has yet to be developed but it appears that management can be adjusted to reduce damage to pastures and there is scope for using resistant species and less susceptible cultivars to escape the disease.

A major research programme is in progress.


The Role Of Nematodes In A South Dakota Grassland Ecosystem, James D. Smolik Jan 1973

The Role Of Nematodes In A South Dakota Grassland Ecosystem, James D. Smolik

Electronic Theses and Dissertations

In an attempt to elucidate the role of nematodes in a grassland ecosystem nematode taxa, number and biomass data was gathered over a three year period at the Cottonwood International Biological Program Grassland Biome site in western South Dakota. The effects of grazing intensity, sampling date and sampling depth were studied. Nematicide treatment of range grasses in field and greenhouse studies was also used to evaluate the role of nematodes. Biomass data was used to estimate the intake of plant feeding nematodes. Results obtained demonstrate that soil inhabiting nematodes constitute a significant proportion of the consumer biomass at the Cotton[1]wood …


Smooth-Stemmed Turnip, B J. Quinlivan, A. C. Devitt Jan 1972

Smooth-Stemmed Turnip, B J. Quinlivan, A. C. Devitt

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

Cruciferous weeds are common throughout the agricultural areas of Western Australia. They include wild turnip, wild mustard, wild radish, charlock and raphistrum weed or short fruited turnip.

Another one—tentatively named smooth-stemmed turnip—has recently been sighted. Its exact weed potential will not be known for some years, but it is likely to spread through the south coastal districts where the climate and sandy surfaced soils favour its growth.


Pit And Scald Of Granny Smiths, Department Of Agriculture, Western Australia Jan 1972

Pit And Scald Of Granny Smiths, Department Of Agriculture, Western Australia

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

Trials investigating storage and shipping disorders of fruit, mainly apples and pears, are conducted annually in cool rooms made available to the Department by the W.A. Meat Export Works.


Wimmera Ryegrass Toxicity, Department Of Agriculture, Western Australia Jan 1972

Wimmera Ryegrass Toxicity, Department Of Agriculture, Western Australia

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

Wimmera ryegrass toxicity has been reported for many years to affect sheep and occasionally cattle in New Zealand, South Australia and the United States of America.

In Western Australia, occasional reports since 1959 and severe outbreaks of staggers in the Katanning- Gnowangerup areas over the last two years prompted the investigation reported below.


Bulletin No 3861 - Kimberley Research Station - Progress Report 1972, J. R. Mcalpine, R. H. Gunn, P. Jakobsen, R. Wetselaar, J. J. Basinski, N. J. Thomson, A. G. L. Wilson, D. H. Mackenzie, A. J. Millington, D. F. Beech, P. C. Owen, B. G. Williams, C. G. Blunt, A. Mcr Holm Jan 1972

Bulletin No 3861 - Kimberley Research Station - Progress Report 1972, J. R. Mcalpine, R. H. Gunn, P. Jakobsen, R. Wetselaar, J. J. Basinski, N. J. Thomson, A. G. L. Wilson, D. H. Mackenzie, A. J. Millington, D. F. Beech, P. C. Owen, B. G. Williams, C. G. Blunt, A. Mcr Holm

Bulletins - 3000 - 3999

The systematic investigations of the potential of the Ord area for irrigated farming began during the Second World War when the possibilities of damming the river were first examined, initial soil survey was carried out, and agricultural experiments started. The Kimberley Research Station was established on its present site in 1945. A year later the State and Commonwealth Governments agreed to finance and operate the Station jointly, with CSIRO and the Western Australian Department of Agriculture being responsible for research.

The construction of the main dam designed to store 5,675 million m" ( 4.6 million acre feet) was completed in …


Glume Blotch Of Wheat, Department Of Agriculture, Western Australia Jan 1972

Glume Blotch Of Wheat, Department Of Agriculture, Western Australia

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

Glume blotch on wheat crops is seen frequently in some areas of Western Australia and was particularly severe in the West Midlands in 1971.

The disease is caused by the fungus Septoria nodorum which infects the leaves, stems and heads of the wheat plant.


The Effect Of Antibiotics On Thermophilic Blue-Green Algae, Erleen Blanche Christenson May 1971

The Effect Of Antibiotics On Thermophilic Blue-Green Algae, Erleen Blanche Christenson

Dissertations and Theses

The nature of the action of penicillin on the cell walls of bacteria is reviewed. The composition of bacterial cell walls is compared to cell walls of blue-green algae.

The test organisms used were thermophilic: Anacystis nidulans grew optimally at 35⁰C, whereas Synechococcus lividus grew best at 45⁰ C. Growth was recorded by reading optical densities.

Cells of these two thermophilic blue-green algae were treated with varying dosages of penicillin and streptomycin. Penicillin inhibited growth of Anacystis nidulans and Synechococcus lividus in concentrations of 3.0 µg/ml and 0.03 µg/ml respectively. However, when 0.3 µg/ml of penicillin was added to Anacystis …


Preparation Of Biologically Active Ribosomal Subunits From Fungal Spores, James L. Van Etten May 1971

Preparation Of Biologically Active Ribosomal Subunits From Fungal Spores, James L. Van Etten

Department of Plant Pathology: Faculty Publications

Ribosomal subunits were prepared from fungal spore ribosomes and reassociated to yield biologically active ribosomes.


Bulletin No 3768 - Submitting Plants For Disease Identification, M D. Marcley Feb 1971

Bulletin No 3768 - Submitting Plants For Disease Identification, M D. Marcley

Bulletins - 3000 - 3999

THERE are several important points to remember when submitting plant material for disease identification by the Department of Agriculture's Plant Pathology Branch.

Firstly it is very important to collect a suitable sample because it is very difficult to determine the cause of a plant disease by looking at a completely dead plant. The sample should include the entire plant (before it is completely dead) including roots and soil. Then all the effects of the disease can be seen. For example leaf yellowing, dead areas of the stem, collar rot, root rot, eelworm damage, and disease of the water and food …


Field Peas : A Crop For The Cereal Growing Areas?, M L. Poole, H. M. Fisher Jan 1971

Field Peas : A Crop For The Cereal Growing Areas?, M L. Poole, H. M. Fisher

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

No abstract provided.


Faulty Germination Of Lupin Seeds, B J. Quinlivan Jan 1971

Faulty Germination Of Lupin Seeds, B J. Quinlivan

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

THE number of lupin seed samples tested in the seed laboratory over the last few years has shown a marked increase with the increasing popularity of lupins as a cash crop.

A seed with satisfactory germination is one which produces a healthy seedling. The germination of lupin samples tested in the laboratory has varied markedly.


Observations On The Establishment Of Seedlings Of Phoradendron Californicum On Prosopis Juliflora, Richard L. Null Jan 1971

Observations On The Establishment Of Seedlings Of Phoradendron Californicum On Prosopis Juliflora, Richard L. Null

Dissertations and Theses

The mistletoe Phoradendron californicum is a common parasite on the mesquite plant Prosopis juliflora. Seeds of the parasite are deposited upon the host plant by birds and perhaps other agents. Normally seedlings of the parasite become established when the elongating radicle of the embryo comes into contact with a host branch and forms a holdfast. From the underside of the holdfast the primary haustorium enters the host tissue and establishes the parasitic union. Later the aerial portion of the parasite develops. Some seeds of P. californicum follow a different sequence; they stimulate the host to produce gum in the tissue …