The use of pathogens native to Europe to control thistles in southern Australia
R.H. Groves and J.J. Burdon, CSIRO Division of Plant Industry, Co-operative Research Centre for Weed Management Systems, GPO Box 1600, Canberra, ACT 2601, Australia.
Foliar pathogens of European thistles that have become significant weeds in southern Australia are listed and the potential for some of them to be classical biological control agents is discussed. Particular attention is paid to pathogens of slender, variegated and saffron thistles. In the case of the slender thistles, the current status of two recently released strains of Puccinia cardui-pycnocephali is presented. Control programs for variegated and saffron thistles are less advanced. Results of recent studies of P. mariana in Europe have thrown doubt on its suitability as a control agent for variegated thistle. In contrast, a survey of pathogens on saffron thistle has shown P. sommeriana to have some potential for biological control. Several pathogens in Europe may have potential to add to the effectiveness of biological control of certain thistles in southern Australian pastures, but only if their effects can be integrated with other methods of control, including biological control by insects.
Plant Protection Quarterly (1996) 11 (Supplement 2) 256-258.