Plant Pathology Commons^™

Yellow Spot Of Wheat, R Loughman, J. M. Wilson, R. E. Wilson

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

Yellow spot is a serious leaf disease of wheat in Western Australia. It also occurs in Queensland, New South Wales and South Australia. Yellow spot can appear as a severe leaf blight but generally the disease does not have the rapid epidemic development of wheat rust diseases. It builds up more slowly and is not as obvious in the crop, while caising appreciable yield loss.

Keeping Ahead Of Powdery Mildew In Barley, T N. Khan, K. Young, P. A. Portmann

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

Powdery mildew is one of the world's most significant barley diseases. In Australia, and more particularly Western Australia, its importance has been under-rated, and only recently has interest in this disease emerged.

Powdery mildew was widespread throughout Western Australia's southern cereal growing areas in 1983. Only a prolonged dry period in August and early September of that year prevented possible large-scale crop losses. Similar outbreaks occurred in 1984.

While some barley varieties are resistant to infection, the use of fungicides, particularly seed dressings, can minimise further infection.

The Stripe Rust Threat, B R. Whan, T. N. Khan

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

The wheat disease stripe rust caused crop losses estimated at $20 million in New South Wales during an epidemis in 983. Economic crop losses were reported in neighbouring States and as far westas Ceduna in South Australia. In some States large areas were sprayed with fungacide at considerable cost to control disease spread.

Wheat stripe rust has not been found in Western Australia yet, but all current evidence indicates that it will eventually reach this State.When it does, it has the potential to cause considerable crop losses every year, unlike the spasmodic losses from stem rust, and it will greatly …

A 'Natural Herbicide' Against Calotrope?, A H. Cheam

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

Buffel grass produces a chemical compound which is toxic to the growth of calotrope seedlings, a declared weed in Western Austrsalia north of the 26th parallel. This new discovery id highly significant in view of the increasing emphasis now placed on weed management as opposed to weed control and the desire to use fewer pesticides.

Blackleg : A Confusing Potato Disease, K Sivasithamparam

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

A disease which causes potato stems to become blackened, soft and rotten has been named 'blackleg' for obvious reasons. It has caused concern among Western Australia's potato growers when outbreaks have appeared in commercial crops. Yet the organisms responsible for these disease symptoms are nothing new andfearsome. In/act they probably have been in this State since vegetables were introduced by the first settlers. The disease has been a headache to research workers seeking to isolate a single organism responsible for such stem rot. The blackleg disease, since its early recognition, has been split into 'typical' and 'atypical' forms. Also, there …

Ryegrass Toxicity Organism Found On Other Grasses, D L. Chatel, J. L. Wise, A. G. Marfleet

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

Yellow slime disease caused by Corynebacterium sp. has recently been found in three grass species.

The diseased grasses were found in the field growing with each other and with affected toxic annual ryegrass.

Breeding A Barley Resistant To Leaf Disease, T N. Khan, P. A. Portmann

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

In the last few years the Department of Agriculture has begun a programme to produce brley varieties resistant to the leaf diseases, scald and net blotch. These diseases cause substantial losses that may not be apparent to an individual farmer.

Halo Blight Of Barley Confirmed In Western Australia, T N. Khan

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

Halo blight on barley has been confirmed in Western Australia for the first time.

What is it and how will it affect barley production in the future?

A New Tissue Test For Accurate Diagnosis Of Copper Deficiency In Cereals, J W. Gartrell, A. D. Robson, J. F. Loneragan

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

Copper deficiency in ceereals can now be accurately diagnosed using tissue analysis.

Symptoms And Treatment Of Copper Deficiency Of Wheat, J W. Gartrell, R. F. Brennan, A. D. Robson

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

Copper deficiency in wheat is still common but may not be easily noticed.

The Potential For Avocados In Western Australia, Michael Gregory Hawson

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

"The flesh of the ripe fruit is ivory yellow, framed in a surround of exquisite green"

There is only one fruit to which this comment can apply and that is the avocado.

While now regarded as a luxury, avocados have met ready demand on major markets indicating that limited expansion of avocado growing in Victoria, South Australia and Western Australiacouldmprovide quite profitable returns.

Progress In Clover Scorch Research, A Bokor, D. L. Chatel, D. A. Nicholas

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

Considerable progress has been made with the clover scorch problem since the devastation of the 971 epidemic when intensive research began.

Over 2000 varieties and crossbreds of subterranean clover from various collections have been screened for resistance resulting in the release of the first resistant clover, Esperance, this year.

Benefits of fungicidal spraying have been demonstrated and low cost spraying programmes for grazed pastures, and seed and hay crops are under field investigation.

Cotton Fireweed : Potential Poison : Research Roundup, J Dickson, R. Hill

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

Although long known as a potential toxic species because of its content, and although it is widely distribuited in all Australian States, cotton fireweed has not generally been consdidered toxic because it is unpalatable and not usually eaten by stock.

In 1973 cattle deaths occured near Ravensthorpe which led to research into Senecio quadridentatus (cotton fireweed).

The plant must be seen as a potential toxic species in situations where the lack of other feed forces cattle to eat the normally unpalatable cotton fireweed.

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

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

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.

Grain Crop Varieties For Western Australia, H M. Fisher

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

Recommendations for grain crop varieties grown in Western Australia are based on the results of field trials carried out each year by the Department of Agriculture at some 50 sites throughout the agricultural areas.

New varieties are tested directly against existing commercial varieties in large scale field trials for several years. Yield and quality results are analysed and market requirements are studied before recommendations are formulated.

This article gives information on the varieties of a range of crops now recommended for growing in Western Australia.

Subterranean Clover In W.A. 1. The Current Situation, B J. Quinlivan, C. M. Francis

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

From small beginnings some 50 or more years ago subterranean clover has come to dominate the pasture scene in Western Australia. Of the 7 000 000 hectares of sown pasture all but some 500 000 are sown to subterranean clover. Further, it is estimated that there remains an area of similar size still to be sown, although in some instances these future sowings will be possible only if suitable varieties are available.

Clearing and pasture development within the various agricultural regions of the State took place, as a rule, within quite clearly defined time intervals and the varieties selected for …

Trikkala, A New Safe Clover For Wet Areas, C M. Francis

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

Trikkala is a new low oestrogen subterranean clover cultivar which has been released to seed producers this year. It should be available in quantity to farmers in 1977 and is recommended as an alternative to Yarloop for winter-wet situations.

Blackleg Of Rapeseed, A Bokor, M. J. Barbetti, A. G. P. Brown, G. C. Mac Nish, P. Mcr. Wood

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

Unless blackleg can be controlled there is little future for rapeseed as a major commercial crop in W.A.

Until 1972, oilseed rape showed great promise as an alternative cash crop for Western Australian farmers, especially in the Great Southern and south coastal areas.

However, like most other cruciferous crops, rape is prone to attack from diseases and insect pests. Most of these can be controlled, but the fungus disease blackleg (Leptosphaeria maculans) emerged as a major threat to the industry.

Clearly, unless the disease can be controlled, there is little future for rapeseed as a major commercial crop in Western …

Promising Results With Pineapples At Carnarvon, Department Of Agriculture, Western Australia

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

Pineapples were investigated commercially in Carnarvon in the early 1930's but drought, sunscorch, alkaline soils and problems with transport and marketing caused the infant industry to collapse in 1936.

Recently however, trials at Gascoyne Research Station have shown that pineapples can produce good yields of high quality fruit in the area.

The trials have been aimed at establishing the viability of pineapple production at Carnarvon and have been carried out by officers of the Horticulture Division.

Breeding Better Rape And Lineseed For Western Australia, N N. Roy, J. Reeves

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

Rapeseed and linseed—the main oil seed crops grown in the south-west of Western Australia—have both been beset by problems which have limited farmers' interest in them.

Rapeseed was first grown commercially in 1970, when wheat quotas and low prices for other cereals forced farmers to seek alternative cash crops. The area sown to rapeseed increased rapidly, but disastrous outbreaks of the disease blackleg caused rapid decline, and little rapeseed is now sown.

Linseed has been grown in W.A. for more than 30 years. Linseed rust proved disastrous but was overcome by the introduction and breedbreeding of rust-resistant varieties. In recent …

Wheat Rust Epidemics, A G P Brown, J. T. Reeves

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

Stem rust of wheat is probably the most damaging plant disease in the world. The rust fungus attacks stems, leaves and heads, producing characteristic red-brown pustules which affect the plant's ability to fill out the grain. Yield loss is directly related to the amount of rust in the crop and the length of time the crop is infected.

In Western Australia it is not uncommon to find rust on crops in mid-October, but usually there is negligible loss of yield. In fact this pattern is quite normal throughout the world: In general, rust arrives too late to cause an epidemic. …

Prospects For A Successful Rape Crop, M J. Barbetti, A. G. P. Brown, P. Mcr. Wood

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

Since the disastrous 1972 season, when blackleg disease reached epidemic proportions, rapeseed production has declined dramatically. With attractive prices for rapeseed in prospect many farmers may be trying this crop again.

If the risk of loss from blackleg could be assessed early in the season it would assist in deciding whether rape would be an economic proposition.

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.

Nitrogen Fertilisers For Pasture Production, Walter Jacob Cox, K Hawley

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

At current prices nitrogen fertiliser is not an economic substitute for good clover pastures, but it can supplement the system by increasing nitrogen supply at peak growth periods. It can also provide useful increases in pasture production at critical feed times. Nitrogen usage for pasture production is still in the experimental stages and small areas should be tried before large-scale application.

The Place Of Lucerne In Western Australian Agriculture, N J. Halse, C. M. Francis

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

Lucerne, the world's most important fodder legume, has never won largescale acceptance in West Australian farming, largely because of our success with productive subterranean clover pastures. But recent disease problems on sub. clover stands have led to greater interest in alternative species, especially lucerne, for higher rainfall areas.

This article summarises our knowledge of lucerne establishment and management in W.A. and reviews current research aimed at achieving better results from lucerne.

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

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.

Potassium For Pastures, Walter Jacob Cox

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

IVIany pastures in the south-west of Western Australia are deficient in potassium or need regular dressings for maximum growth. This article indicates areas and situations in which potassium might be needed, shows how deficiency is diagnosed and gives recommended rates of application.