What: Fourth World Congress in Allelopathy: "Establishing the Scientific Basis"

When: Sunday 21 to Friday 26 August 2005

Where: Convention Centre, Charles Sturt University, Wagga Wagga, NSW, Australia.

• Professor Azim Mallik: President, International Allelopathy Society. Professor of Biology, Lakehead University, Thunder Bay, Ontario, Canada. Professor Mallik will speak on Allelopathy: advances, challengers and opportunities. His research interests include progressive and retrogressive succession in relation to regeneration strategies and chemical ecology of plants following ecosystem disturbances such as fire and logging.

• Doctor Margaret McCully: CSIRO Plant Industry, Canberra, Australia. Dr McCully’s diverse training has given her a broad outlook. She has touched upon many areas of science, from phycology to microbiology, from anatomy to physiology. She is best known, however, as an expert in root biology. Born in Canada, she completed her master’s degree in plant ecology the University of Toronto. In 1966, she completed her PhD at Harvard in cell biology on the histology of the brown alga Fucus. She came back to Canada to take a faculty position at Carleton University in Ottawa where she spent the vast majority of her academic career before coming to Australia. She has held visiting fellowships, lectureships or professorships at the University of Leeds and Oxford University in the UK, the University of California, and Monash University, the University of Melbourne, LaTrobe University, and the University of Western Australia.

The rhizosphere is the environment in which roots function in the soil. This environment, created and managed by the roots themselves, is spatially and temporally heterogeneous. Rhizospheres develop, mature and senesce in parallel with developmental changes in adjacent regions of the subtending root, and they remain as relics after root death, often as biopores, which in hard soils are occupied by many of the roots of the subsequent crop. To use allelopathy as an effective biological control in particular field environments, it is crucial to know more about how the production and effectiveness of specific allelochemicals are affected by developmental changes in the root and rhizosphere, and by the placement of roots of donor and target plants in relation to their respective current and relic rhizospheres.

• Doctor Alexa Seal: Charles Sturt University, NSW, Australia. In November 2003, she was awarded her PhD for rice allelopathy research.

Australia’s high rice yields are jeopardised by the presence of weeds, many of which are native to Australia. This paper reviews the rice allelopathy research which has been conducted in Australia on Australian rice weeds over the past six years. Both laboratory and field research have been undertaken to confirm that allelopathic interactions exist in the system, to identify cultivars with high allelopathic potential, and to substantiate the impact of these cultivars in a field situation.

• Professor Ragan Callaway: University of Montana, Missoula, Montana, USA. In studies on how plants interact with one another, Professor Callaway has found that spotted knapweed conducts chemical warfare on its neighbours—the first comprehensive evidence of an invasive plant using an offensive chemical weapon. 

Many exotic plant species undergo astounding increases in dominance when introduced to new communities by humans. We think that some invaders may become much more abundant abroad because they possess novel biochemical weapons that function as unusually powerful allelopathic agents against species without evolved tolerance.