Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

Plant Pathology

Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 11371 - 11400 of 11634

Full-Text Articles in Life Sciences

The Effect Of Straw On The Emergence Of Wheat Seedlings, W A. Shipton, W. R. Tweedie Jan 1967

The Effect Of Straw On The Emergence Of Wheat Seedlings, W A. Shipton, W. R. Tweedie

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

The emergence of wheat seedlings was decreased substantially when seed was planted close to oaten straw.

When the grain was placed a 1/4 inch above a straw layer emergence was depressed by more than half.


Cereal Root Eelworm, O M. Goss Jan 1967

Cereal Root Eelworm, O M. Goss

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

CEREAL ROOT EELWORM* has recently been recorded from the older farming districts of Western Australia.

This eelworm can attack most cereals and grasses but is more damaging to wheat and oats.


Phalaris Staggers : Prevention By Cobalt Bullets, Bryan J. Gorddard, P. P. Mann, A. J. Hadlow Jan 1967

Phalaris Staggers : Prevention By Cobalt Bullets, Bryan J. Gorddard, P. P. Mann, A. J. Hadlow

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

FARMERS in the south west of Western Australia are familiar with the use of cobalt for the prevention of ill-thrift and deaths due to cobalt deficiency in sheep and cattle.

Less common is the use of cobalt for the prevention of chronic phalaris poisoning, known as phalaris staggers.

This condition is well known in eastern Australia, but only isolated cases have been recorded in W.A. no doubt due to the relatively small area sown to phalaris in this state.


A Survey Of Verticillium Albo-Atrum From Tomato Fields Of Northern Utah, Jean Redmond Musselman May 1966

A Survey Of Verticillium Albo-Atrum From Tomato Fields Of Northern Utah, Jean Redmond Musselman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Verticillium wilt has long been a major disease of tomatoes in Utah. The disease was recognized long before the causal agent was known. In 1932, Dr. H. L. Blood was given the task of investigating a wilt disease that was causing heavy losses to Utah's tomato industry (5). The disease was thought to be caused by Fusarium oxysporum f. lycopersici (Sacc.) Snyder & Hansen. Through his investigations Dr. Blood found Verticillium albo-atrum Reinke and Berthold to be the cause of the disease. He began the laborious task of finding a resistant variety of tomato and transferring the resistance to commercial …


Studies Of Peronspora Trifoliorum Debary Cause Of Downy Mildew Of Alfalfa, Sheldon B. Waite May 1966

Studies Of Peronspora Trifoliorum Debary Cause Of Downy Mildew Of Alfalfa, Sheldon B. Waite

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Downy mildew of alfalfa (caused by Peronospora trifoliorum d By) was found to be epidemic on susceptible varieties of alfalfa in northern Utah during 1965. The increase in the amount of downy mildew present was due to the more abundant rainfall and cooler than normal temperatures which prevailed during the summer months of 1965 (Environmental Science Services Administration, 1965). The author observed many of the highly susceptible varieties of alfalfa had 25-30 percent of their leaflets infected with the downy mildew fungus. Because of the epidemic developments of alfalfa downy mildew, an investigation was undertaken to explore the following questions …


A Cytological Study Of Germinating Aeciospores In The Cronartium Coleosporioides Complex, John A. Christenson May 1966

A Cytological Study Of Germinating Aeciospores In The Cronartium Coleosporioides Complex, John A. Christenson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Peridermium harknessii Moore, causal agent of western gall rust, is responsible for deformation, cull and death of pine. In the West it is most serious on lodgepole and ponderosa pines. Seedlings and mature trees may be seriously attacked (Peterson, 1960). Gall rust is easily recognized by its branch galls and trunk cankers. Interest in the disease has fluctuated, but it is considered important enough that government monies support research on the disease in both the United States and Canada.


Thrips Damage Of Grapes, A N. Sproul Jan 1966

Thrips Damage Of Grapes, A N. Sproul

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

IN mid-December, a few bunches of Semillon grapes were submitted for examination from a Caversham Vineyard.

Damage to grape berries by thrips has not been recorded before in Western Australia.


Inoculation And Pelleting Of Lupin And Serradella Seed, W A. Shipton, C. A. Parker Jan 1966

Inoculation And Pelleting Of Lupin And Serradella Seed, W A. Shipton, C. A. Parker

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

LUPINS AND SERRADELLA are not as extensively grown in Western Australia as some other legumes, but they are useful pasture species, particularly on poorer sandy soils.

Virgin soils may contain rhizobial bacteria capable of nodulating some members of the lupin group, but none of these bacteria have been found to nodulate serradella (Lange, 1961).

The use of inoculated seed is imperative except where lupins have been grown before.


Net Blotch Of Barley, W A. Shipton Jan 1966

Net Blotch Of Barley, W A. Shipton

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

NET BLOTCH is the most prevalent disease of barley in Western Australia, and is capable of reducing yields considerably.

It is caused by the fungus Pyrenophora teres Drechsl.


Septoria Leaf Spot And Glume Blotch Of Wheat, W A. Shipton Jan 1966

Septoria Leaf Spot And Glume Blotch Of Wheat, W A. Shipton

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

SEPTORIA leaf spot and glume blotch of wheat occur throughout Australia and are capable of reducing crop yields.

While no estimates of yield losses are yet available in Western Australia both diseases can cause serious damage to crops.


Organo-Phosphorus Insecticides For Control Of Red-Legged Earth Mite And Lucerne Flea, J A. Button Jan 1966

Organo-Phosphorus Insecticides For Control Of Red-Legged Earth Mite And Lucerne Flea, J A. Button

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

MOUNTING CONCERN over residue problems arising from the use of D.D.T. and other chlorinated hydrocarbon insecticides on pasture has highlighted the need for alternative chemicals capable of providing satisfactory control without undesirable side effects.


Citrus Rootstocks : An Evaluation For New And Replant Areas, Department Of Agriculture, Western Australia Jan 1966

Citrus Rootstocks : An Evaluation For New And Replant Areas, Department Of Agriculture, Western Australia

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

Widespread decline of citrus orchards in Western Australia associated with Phytophthora root rot, citrus eelworm and other factors has prompted investigation of various citrus rootstocks.

Trifoliata and Troyer citrange are most suitable for replant areas.

Wider use of these and of other stocks such as sweet orange is advocated for new plantings.


Black Spot Of Peas, Department Of Agriculture, Western Australia Jan 1966

Black Spot Of Peas, Department Of Agriculture, Western Australia

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

THIS fungous disease of peas causes "black spot" and "stem rot" on affected plants. During the wet winter months the disease is often so severe that it is difficult to grow garden pea varieties satisfactorily; but in summer when hot, dry conditions usually prevail the disease is of little consequence.


Downy Mildew Of Crucifers, G C. Macnish Jan 1966

Downy Mildew Of Crucifers, G C. Macnish

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

DOWNY mildew of crucifers is of world wide distribution.

In other parts of the world it has been recorded on a number of cruciferous plants, but to the present time this disease has only been recorded on cauliflower and cabbage in Western Australia.


Changes In Fungi With Age I. Chemical Composition Of Rhizoctonia Solani And Sclerotium Bataticola , David Gottlieb, James L. Van Etten Jan 1966

Changes In Fungi With Age I. Chemical Composition Of Rhizoctonia Solani And Sclerotium Bataticola , David Gottlieb, James L. Van Etten

Department of Plant Pathology: Faculty Publications

The chemical composition of the mycelium of Rhizoctonia solani and Sclerotium bataticola was determined in cells of various ages. The percentage, per unit of dry weight, of soluble amino nitrogen, deoxyribonucleic acid (DNA), ribonucleic acid (RNA), ergosterol, and protein decreased with age in both fungi. Total lipids and fatty acids increased with age in S. bataticola but remained constant in R. solani. Total carbohydrate increased with age in R. solani and decreased in S. bataticola. Fewer changes with age were observed when the results were calculated in ratio to DNA. There was no change in the ratios of protein, …


Changes In Fungi With Age Ii. Respiration And Respiratory Enzymes Of Rhizoctonia Solani And Sclerotium Bataticola, James L. Van Etten, H. Peter Molitoris, David Gottlieb Jan 1966

Changes In Fungi With Age Ii. Respiration And Respiratory Enzymes Of Rhizoctonia Solani And Sclerotium Bataticola, James L. Van Etten, H. Peter Molitoris, David Gottlieb

Department of Plant Pathology: Faculty Publications

The rate of respiration of Rhizoctonia solani and Sclerotium bataticola decreased with age. This decrease in respiratory rate might be produced by a decrease in the specific activity of one or more enzymes involved in carbohydrate metabolism. Specific activities in cell-free extracts were measured for most of the enzymes in the hexose monophosphate shunt, Embden-Meyerhof-Parnas pathway, tricarboxylic acid cycle, and terminal electron-transport system. In addition, glucose oxidase, isocitritase, and malic enzyme were measured. In R. solani, increases in activity with age occurred for hexokinase, α-glycerolphosphate dehydrogenase, malic dehydrogenase, and cytochrome oxidase. Decreases occurred for phosphohexokinase, aconitase, nicotinamide adenine dinucleotide-specific …


The Elimination Of Cultivation In Apple Orchards : A New Approach To Orchard Soil Management, S E. Hardisty Jan 1966

The Elimination Of Cultivation In Apple Orchards : A New Approach To Orchard Soil Management, S E. Hardisty

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

THE idea of eliminating cultivation in orchards suggests a reversal of accepted local practice in orchard soil management—but there is plenty of evidence to show that a noncultivation system has much in its favour.

In this article the advantages and disadvantages of the three main forms of orchard soil management are discussed and experimental evidence is presented in support of noncultivation.

An alternative method, "winter sod" culture, is proposed for irrigated orchards.


Summer And Autumn Rainfall In Relation To Epidemics Of Wheat Stem Rust In Western Australia, W A. Shipton Jan 1966

Summer And Autumn Rainfall In Relation To Epidemics Of Wheat Stem Rust In Western Australia, W A. Shipton

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

High summer and autumn rainfalls, followed by rust infection of volunteer plants and favourable conditions during late winter and spring, lead to rust epidemics.

WIDESPREAD outbreaks of wheat stem rust are rare in Western Australia.


Loquat Diseases : Black Spot And Fleck, R F. Doepel Jan 1966

Loquat Diseases : Black Spot And Fleck, R F. Doepel

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

Black spot is common on loquats and renders affected fruit unmarketable.

Another disfiguring fungal disease, fleck, has also become established in this State.

The newer fungicide dodine is recommended for controlling both these diseases.


Leaf Scorching, Department Of Agriculture, Western Australia Jan 1966

Leaf Scorching, Department Of Agriculture, Western Australia

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

DURING the summer months, leaves of many plants develop browning and scorching which progresses inwards from the leaf margin or downwards from the leaf tip.

The affected parts become dry and brittle and may break away from the remaining green areas.


The 1965 Ord River Cotton Crop, G D. Oliver, A. W. Hogstrom Jan 1966

The 1965 Ord River Cotton Crop, G D. Oliver, A. W. Hogstrom

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

THE financial results of 18 cotton growers in the Ord River Valley during the 1965 season were obtained during a survey conducted in August, 1965.

All farmers who have been allocated blocks and who grew cotton in 1965 were included in the survey.*


A Study Of The Development Of The Sexual Stage Of Rhytisma Punctatum (Pers.) Fries, Ching-Fei Chen May 1965

A Study Of The Development Of The Sexual Stage Of Rhytisma Punctatum (Pers.) Fries, Ching-Fei Chen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Speckled tar spot caused by Rhytisma punctatum (Persoon) Fries is often found on maples in many parts of the world (Holden, 1961; Koval', 1960; Saccardo, 1889). In Northern Utah it develops every year on leaves of Acer grandidentatum Nutt., and it is especially abundant at elevations above 6,000 feet, where often it is difficult to find even one uninfected leaf. The black speckled spots and the associated leaf coloring tend to add to the brilliance of the autumn colors normally found in the leaves of Bigtooth Maple.


Mechanical Transmission Of A Latent Virus From Apple To Herbaceous Plants, Ali Majid Jafri May 1965

Mechanical Transmission Of A Latent Virus From Apple To Herbaceous Plants, Ali Majid Jafri

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recent work has shown that viruses are widely disseminated in commercial apple trees growing in this country (1, 14, 16, 17)—quite often one or more latent viruses are found in these plants. Usually latent viruses produce no symptoms, except in special indicator hosts. Latent viruses may cause severe injury when infected plants are grafted to a sensitive variety or rootstock. Actual damage caused by most of the apple viruses is not known but some of these definitely cause serious losses. Experimental plots at Utah State University were ruined by stem pitting virus infection. However, other latent viruses were also present …


Studies On The Relationship Of Polygalacturonase Inhibitors To Verticillium Wilt Resistance In Tomatoes, Robert Lee Sneed May 1965

Studies On The Relationship Of Polygalacturonase Inhibitors To Verticillium Wilt Resistance In Tomatoes, Robert Lee Sneed

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Early studies of the vascular wilts were directed toward understanding the wilting of susceptible varieties (19, 22, 23). Only in recent years have workers begun to study plant resistance to Fusarium and Verticillium wilts.


Biochemical Changes During The Growth Of Fungi: Ii. Ergosterol And Fatty Acids In Penicillium Atrovenetum, David Gottlieb, James L. Van Etten Feb 1965

Biochemical Changes During The Growth Of Fungi: Ii. Ergosterol And Fatty Acids In Penicillium Atrovenetum, David Gottlieb, James L. Van Etten

Department of Plant Pathology: Faculty Publications

Changes in the lipid constituents of Penicillium atrovenetum were studied during the growth and development of this fungus. The stages in development, as measured by the dry weight, were divided into four phases: lag, log, stationary, and death. The total fatty acids on a dry-weight basis increased from a minimum in the spores to a maximum near the end of the log phase of growth. The major fatty acids were palmitic, stearic, oleic, and linoleic. Myristic, pentadecanoic, palmitoleic, heptadecanoic, linolenic, arachidic, and heptadecenoic acids, together with two unidentified components, were also present in the fatty acid fraction. Compared to ungerminated …


Nodulation Of Legumes On New Light Land. 1. Survival Of Rhizobia On Inoculated Pelleted Seed Held For Varying Periods Before Sowing Into Dry Soil, O M. Goss, W. A. Shipton Jan 1965

Nodulation Of Legumes On New Light Land. 1. Survival Of Rhizobia On Inoculated Pelleted Seed Held For Varying Periods Before Sowing Into Dry Soil, O M. Goss, W. A. Shipton

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

MOST of the light land areas being opened up in Western Australia are very sparsely populated with the rhizobial bacteria so essential for successful legume establishment.

Seed inoculation is therefore a necessity.

Farmers often have to resort to dry sowing because of the large acreages being planted or late opening rains.


Nodulation Of Legumes On New Light Land. 4. Rhizobial Strains For Pasture Establishment, O M. Goss, W. A. Shipton Jan 1965

Nodulation Of Legumes On New Light Land. 4. Rhizobial Strains For Pasture Establishment, O M. Goss, W. A. Shipton

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

LEGUMES are the basis of improved pastures in Western Australia.

Successful establishment of these legumes depends on the presence in the soil of suitable bacteria which will invade the roots and develop nodules in which nitrogen fixation is carried out. The nitrogen compounds produced are utilised by the plants, making them independent of soil nitrogen.

At the end of the season, the decomposition of the plant residues improves soil fertility.


Root Growth Of Apple Trees, J E L Cripps Jan 1965

Root Growth Of Apple Trees, J E L Cripps

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

IT will surprise even experienced growers to know that an apple tree in W.A. needs twice the quantity of roots the same tree would need in a more temperate climate such as England's.


Black Spot And Powdery Mildew Of Grapes, H L. Harvey Jan 1965

Black Spot And Powdery Mildew Of Grapes, H L. Harvey

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

BLACK spot (or anthracnose) and powdery mildew (or oidium) are diseases that occur commonly on grape vines in W.A.


Grease Spot Of Passion Fruit, R F. Doepel Jan 1965

Grease Spot Of Passion Fruit, R F. Doepel

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

PROLONGED wet periods during the winter months favour serious development of the bacterial disease grease spot in passion vine plantations.