THE LIFE-CYCLE AND ECOLOGY OF CYPERUS-DIFFORMIS (RICE WEED) IN TEMPERATE AUSTRALIA - A REVIEW

The almost exclusive use of aerial sowing of rice in Australia and the concomitant reliance upon the herbicide bensulfuron-methyl to control Cyperus difformis has not been matched with an increase in the unders tanding of the biology of this major weed. Of great significance is th e recent discovery of C. difformis biotypes in California which are re sistant to bensulfuron-methyl. Although Australian rice agroecosystems employ longer rotations than the intensive California systems, it is only a matter of time until resistant biotypes are identified in Austr alia. This paper identifies the life cycle characteristics of C. diffo rmis that we need to understand for its future management.