Peronosclerospora sorghi does not occur in Australia
Sorghum downy mildew caused by Peronosclerospora sorghi does not occur in Australia. There had been records in the past but these are now considered erroneous. The record of P. sorghi in Queeensland is definitely incorrect because specimens of a downy mildew on maize, which were initially identified as P. sorghi were re-examined and considered to be P. maydis. In Western Australia, P. sorghi was recorded on maize in a quarantine block in 1989 but this is now considered extremely doubtful because the conidia were very similar to those recorded later as P. maydis in northern Queensland.
The situation of Peronosclerospora sorghi in Australia can be described as follows: Absent, invalid record.
Sources
Biosecurity Australia, 2007-02.
Wang E, Ryley M, Meinke H (2000) Prediction of sorghum downy mildew risk in Australia using daily weather data. Australasian Plant Pathology 29(2), 108-119.