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Sediment metal concentrations in embayments of Sydney Harbour, acquired from the literature and from samples collected for this study, were used to generate contaminant probability density distributions using AQUARISK. The sediment metal concentrations often exceeded Australia's interim sediment quality guidelines. Similarly, estuarine spiked sediment toxicity test literature provided adverse biotic effects concentration data to generate species sensitivity distributions using AQUARISK. Although the harbor is subject to other inorganic and organic contamination, we have used sediment metals to demonstrate an approach for ecological risk mapping and environmental management prioritization. Sufficient spiked sediment toxicity test data were found for only three metals—Cd, Cu, and Zn—and some tests were likely to overestimate toxicity. The estimates of the hazardous concentration to 5% of species (the 50th percentile of the 95% species protection level) were 5, 12, and 40 mg/kg DW of total sediment metal for Cd, Cu, and Zn, respectively. These values were generally low when compared with the interim sediment quality guidelines due to the overestimation of toxic effects in the literature data. The parameters for the species sensitivity distributions have been combined with the measured sediment metal concentrations in Homebush Bay to generate risk maps of the estimated species impact for each metal as well as for all three metals collectively assuming proportional additivity. This has demonstrated the utility of comparing contaminants on a consistent scale—ecological risk. [ABSTRACT FROM AUTHOR]

Botrytis fabae spore suspensions containing c. 1, 10, 102, 103, 10\ 105, or 106 spores/ml were used to inoculate 5, 17 or 30-day-old field bean leaves. The percentages of the leaf areas covered by chocolate spot lesions and the percentages of the leaf areas bearing conidiophores were assessed 1, 6, 12,14, and 19 days after inoculation. The percentage of the area covered by lesions and the percentage of the area bearing conidiophores (logit-transformed) increased linearly with increasing spore concentration (log10-transformed). The proportions of leaf areas covered by lesions and bearing conidiophores were both greater on 17 and 30-day-old leaves than on 5-day-old leaves. The rate of lesion growth increased with both increasing inoculum dose and increasing leaf age. Generally there was no interaction between the effects of leaf age and the effects of inoculum dose on either lesion growth or sporulation. Two days after inoculation with suspensions of either 104 or 106 spores/ml, 7-day-old leaves grown at 15°C were transferred to -16°C or 2.5°C or kept at 15°C for 4 days. Two days later more spores had been produced on leaves which had been frozen (-16°C) than on leaves kept at 2.5 °C. [ABSTRACT FROM AUTHOR]

W-type isolates of Pseudocercosporella herpotrichoides grown on a maize-based agar and exposed to near- ultra-violet radiation at c. 13°C produced a greenish black colour, whilst R-type isolates produced a pink or pale brown colour in the agar medium. More colonies from directly plated lesions or from spore suspensions could be recognized as P. herpotrichoides and could be more easily differentiated as W-type or R-type or as mixtures of both by colour production on maize agar (MA) than by colony morphology on potato dextrose agar (PDA), despite the presence of other fungi. Isolates with intermediate morphology on PDA were positively identified as W-type or R-type on MA; their pathogenicities to wheat and rye seedlings were usually similar 10 those of W-type or R-type isolates with typical colony morphology, confirming their identification on MA. Drops of mixed suspensions of W- type and R-type spores on PDA formed fast-growing colonies with smooth margins which sometimes had slow-growing sectors with feathery margins. Drops of the same mixtures on MA formed greenish black colonies which sometimes had pink or pale brown sectors. However, when these mixtures were spread onto MA. W-type and R-type colonies could easily be differentiated by colour. [ABSTRACT FROM AUTHOR]