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Puccinia psidii has long been considered a significant threat to Australian plant industries and ecosystems. In April 2010, P. psidii was detected for the first time in Australia on the central coast of New South Wales (NSW). The fungus spread rapidly along the east coast and in December 2010 was found in Queensland (Qld) followed by Victoria a year later. Puccinia psidii was initially restricted to the southeastern part of Qld but spread as far north as Mossman. In Qld, 48 species of Myrtaceae are considered highly or extremely susceptible to the disease. The impact of P. psidii on individual trees and shrubs has ranged from minor leaf spots, foliage, stem and branch dieback to reduced fecundity. Tree death, as a result of repeated infection, has been recorded for Rhodomyrtus psidioides. Rust infection has also been recorded on flower buds, flowers and fruits of 28 host species. Morphological and molecular characteristics were used to confirm the identification of P. psidii from a range of Myrtaceae in Qld and compared with isolates from NSW and overseas. A reconstructed phylogeny based on the LSU and SSU regions of rDNA did not resolve the familial placement of P. psidii, but indicated that it does not belong to the Pucciniaceae. Uredo rangelii was found to be con-specific with all isolates of P. psidii in morphology, ITS and LSU sequence data, and host range. [ABSTRACT FROM AUTHOR]

Australian wheat consigned for export from Australian ports was surveyed in March 2004 using a national diagnostic protocol for detection and identification ofTilletia indica. No ustilospores ofT. indicawere detected, confirming previous surveys which have failed to detectT. indicain Australia. However, the survey detected moderate levels of the common smutsTilletia caries(syn.Tilletia tritici),Tilletia laevisandUrocystis agropyri, and very low levels (average fewer than six ustilospores per 150 g sample) of an unidentified dark, tuberculate-sporedTilletiain≈ 60% of samples tested. Comparison with herbarium specimens enabled identification of the majority of the tuberculate ustilospores asTilletia ehrhartae, a smut fungus known to infect onlyEhrharta calycina(perennial veldt grass) and which is common in southern Australia. A smaller number of tuberculate smut ustilospores were identified asTilletia walkeri, a smut ofLoliumspp. recorded in Australia but apparently uncommon. BothT. ehrhartaeandT. walkeribear sufficient resemblance toT. indicafor misidentifications to be possible where only a very few ustilospores are seen, althoughT. ehrhartaeustilospores are always<25  µm in diameter. The frequent presence of ustilospores of bothT. ehrhartaeandT. walkerias contaminants of Australian wheat grain exports has significance for diagnosticians testing Australian export wheat, as it demonstrates the potential for tuberculate ustilospores of species other than those covered in existing diagnostic protocols to be misidentified asT. indica. This paper describesT. ehrhartaein detail, and provides criteria for its differentiation fromT. indica,T. walkeriand some other species. [ABSTRACT FROM AUTHOR]

A new, fatal mycotoxicosis of cattle has been recognised in north-western Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corallocytostroma that grows on Mitchell grass (Astrebla spp). The disease has been colloquially named 'black soil blindness' because its most prominent features are its confinement to pastures on black soil, and blindness and death of affected animals. Over 500 cattle have died and considerable subclinical disease in present. Above average wet season rainfall and extended growing seasons may explain the emergence of the fungus. The disease is important because cattle production in large areas of Australia utilise Mitchell grass pastures.