Approaches used in the prediction of weed population dynamics

The design and evaluation of weed management systems, including systems bas ed on herbicide resistant crops, requires quantitative insight into the pop ulation dynamics of weeds. It may help to identify risks and changes in wee d vegetation development and may be useful for the determination of new con trol techniques that disrupt the life cycle of resistant weeds at some poin t in time. Such insight may also be useful to develop management technologi es and to develop strategies for weed management. The complexity and the lo ng-term nature of weed population dynamics make the use of models essential . Different modelling approaches have been developed and are described brie fly. Opportunities for applying these techniques to improve weed management systems, including systems based on herbicide resistant crops, and require ments for further research are discussed.