Chemical management of annual ryegrass.

摘要

The role of the use of selective herbicides on the development of resistance in Lolium rigidum is discussed, and current options for the chemical control of this weed in Australia are reviewed. Chemical control of herbicide-susceptible populations,and the use and effectiveness of pre-plant., and early and late post-em. herbicides in its management are considered. Currently 7 herbicides are registered for selective removal of L. rigidum in cereal crops, although more are available for control in broadleaved crops, and non-selective herbicides are increasingly used post-em. The limited prospects for chemical management of herbicide-resistant L. rigidum are outlined. Resistance has been identified in _11% of surveyed populations, and the extent of resistance to different herbicide types is examined. Problems of cross-resistance are also discussed. Currently most programmes against resistant populations are based on glyphosate and paraquat.