Prevalence of sclerotinia stem rot of canola in New South Wales

2003 ◽  
Vol 43 (2) ◽  
pp. 163 ◽  
Author(s):  
T. L. Hind ◽  
G. J. Ash ◽  
G. M. Murray
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
New South ◽  
New South Wales ◽  
Stem Rot ◽  
Sclerotinia Stem Rot ◽  
Mean Values ◽  
Stem Infection ◽  
South Wales

Surveys of petal infestation and stem infection conducted in 1998, 1999 and 2000 indicated that Sclerotinia sclerotiorum poses a threat to the Australian canola industry. Inoculum was present throughout all canola-growing regions of New South Wales and the stem disease was widespread throughout southern New South Wales. Percentage petal infestation increased over the 3 years surveyed with values ranging from 0 to 99.4%. The highest petal infestation values were observed in 2000 (maximum of 99.4%, mean of 82.2%), with lower mean values in 1998 (38.4%) and 1999 (49.6%). Stem infection ranged from 0 to 37.5% and most fields had less than 10% stem infection. Stem rot incidence before harvest did not relate to percentage petal infestation determined during flowering. This indicated that factors other than percentage petal infestation were important in influencing stem rot incidence. While there was no relationship between percentage petal infestation and stem rot incidence, stem infection never occurred without prior petal infestation.

Natural enrichment of topsoils with chromium and other heavy metals, Port Macquarie, New South Wales, Australia

Soil Research ◽  
1997 ◽  
Vol 35 (5) ◽  
pp. 1165 ◽  
Author(s):  
Bernd G. Lottermoser
Keyword(s):  
Heavy Metal ◽  
Surface Soil ◽  
New South ◽  
New South Wales ◽  
Soil Samples ◽  
Metal Concentrations ◽  
Mean Values ◽  
Heavy Metal Concentrations ◽  
Environmental Investigation ◽  
South Wales

Total heavy metal concentrations [cobalt (Co), chromium (Cr), copper(Cu), iron (Fe), mangnese (Mn), nickel (Ni), lead (Pb), and zinc (Zn)]were determined in surface soil samples from Port Macquarie, New South Wales,Australia. Composite topsoil samples (0–10 cm depth) had mean values(per kg) of 13 mg Co, 1020 mg Cr, 59 mg Cu, 136·7 g Fe, 719 mg Mn, 149mg Ni, 20 mg Pb, and 47 mg Zn. The topsoils were generally characterised by alow pH (3·8–5·2) and a mineralogy dominated by haematite,magnetite, quartz, and kaolinite. Chromium was predominantly present in thetopsoils as Cr3+ in microcrystalline chromite(FeCr2O4) and, to a lesser degree,in kaolinite and haematite. Differences in Cr soil concentrations with depthwere due to variations in the relative abundance of the various soilcomponents, rather than Cr3+ mobility within the soilprofile. The elevated heavy metal concentrations are the result of soildevelopment over metal-rich bedrock (serpentinite matrix melange) andassociated enrichment of relatively immobile elements (Cr, Fe, Ni) in theresidual soil profile. The ANZECC and NH&MRC (Australian and New ZealandEnvironment and Conservation Council and National Health & MedicalResearch Council) environmental investigation limits were exceeded for100% of the sample sites for Cr, 47% for Cu, 61% for Mn,and 58% for Ni.

Impact of tillage on lupin growth and the incidence of pathogenic fungi in southern New South Wales

2004 ◽  
Vol 44 (1) ◽  
pp. 53 ◽  
Author(s):  
S. Simpfendorfer ◽  
D. P. Heenan ◽  
J. A. Kirkegaard ◽  
K. D. Lindbeck ◽  
G. M. Murray
Keyword(s):  
New South ◽  
New South Wales ◽  
Pathogenic Fungi ◽  
Early Growth ◽  
Brown Spot ◽  
Stem Rot ◽  
Wheat Crop ◽  
Seedling Vigour ◽  
South Wales ◽  
Lower Biomass

Narrow-leafed lupins (Lupinus angustifolius) were grown in cultivated and direct-drilled plots at 4 field sites in southern New South Wales in 1998 to determine the effect of tillage on seedling vigour, disease and yield. The early growth of lupins in direct-drilled plots was reduced compared with seedlings in cultivated plots at 3 of the sites. However, the biomass of lupin plants in the direct-drilled treatments was 20% greater than in adjacent cultivated plots at harvest. The lower biomass in cultivated plots appeared to be primarily related to an increased incidence and severity of stem rot caused by Sclerotinia sclerotiorum. The increased stem rot in cultivated plots was also associated with a decline in yield of between 16 and 35% across the sites compared with direct-drilled plots. The direct-drilled treatment reduced the severity of brown spot, caused by Pleiochaeta setosa, at the 2 sites where stubble was retained from the previous wheat crop. These results suggest that direct drilling into cereal residue provides benefits over cultivation for the growth of lupins in southern New South Wales where crop infection by Sclerotinia and/or brown spot may be significant.

Objective derivation of macro invertebrate family sensitivity grade numbers for the SIGNAL biotic index: application to the Hunter River system, New South Wales

1997 ◽  
Vol 48 (2) ◽  
pp. 159 ◽  
Author(s):  
Bruce C. Chessman ◽  
Jane E. Growns ◽  
Amanda R. Kotlash
Keyword(s):  
Iterative Algorithm ◽  
Environmental Quality ◽  
Environmental Variables ◽  
New South ◽  
New South Wales ◽  
River System ◽  
Biotic Index ◽  
Mean Values ◽  
South Wales ◽  
Highly Correlated

Chessman's SIGNAL-95 biotic index was modified on the basis of data from spring and autumn surveys of macroinvertebrates at 42 sites in the Hunter River and tributaries. An iterative algorithm was used to derive improved grade numbers reflecting the pollution sensitivities of individual families of river macroinvertebrates. The new grades were used to calculate values of the modified index (SIGNAL-HU97). These values were highly correlated with SIGNAL-95 values but were more widely spread, giving better discrimination between the sites of higher environmental quality and the more degraded sites. SIGNAL-HU97 values were also more highly correlated than were SIGNAL-95 values with environmental variables such as the conductivity of the water and a riparian, channel and environmental inventory. There was little difference in values between spring and autumn, but riffles consistently had higher mean values than other habitats.

The prevalence and severity of diseases in the coastal soybean crop of New South Wales

1991 ◽  
Vol 31 (4) ◽  
pp. 545 ◽  
Author(s):  
GE Stovold ◽  
HJP Smith
Keyword(s):  
Pseudomonas Syringae ◽  
Xanthomonas Campestris ◽  
New South ◽  
Soybean Mosaic Virus ◽  
New South Wales ◽  
Coastal Region ◽  
Leaf Blight ◽  
Stem Rot ◽  
Phytophthora Megasperma ◽  
South Wales

Rainfed soybean (Glycine max) crops in the northern coastal region of New South Wales were surveyed from 1985 to 1987 for the prevalence and severity of diseases. Sixteen diseases were recorded over the 3 seasons, but only rust (Phakopsora pachyrhizi), black leaf blight (Arkoola nigra) and bacterial pustule (Xanthomonas campestris pv. glycines) were present each season. Rust was the most significant disease, infecting 50, 20 and 6% of crops in 1985, 1986 and 1987. The severity of rust was related to rainfall and temperature after flowering, with the most severe outbreaks in the higher rainfall area of the lower Richmond Valley. Black leaf blight was also significant and occurred in 39, 10 and 27% of crops in 1985, 1986 and 1987, but in most crops severity was low. The other diseases recorded were downy mildew (Peronospora manschurica), root and stem rot (Phytophthora megasperma f. sp. glycinea), stem canker (Rhizoctonia sp.), pod and stem blight (Phomopsis spp.), anthracnose (Colletotrichum spp.), seedling blight (Rhizoctonia sp.), stem rot (Phytophthora sp.), white mould (Sclerotinia sclerotiorum), flower blight (Botrytis cinerea), leaf spot (Phoma sp.), bacterial blight (Pseudomonas syringae pv. glycinea), mosaic (soybean mosaic virus) and orange bark (not identified). All of these diseases were generally of low prevalence and severity.

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