&rqwulexwlrqq Ri Irupdoo Prghoolqjj Dqgg Ilhogg H[shulphqww Wrr Ohyhudjhh Nqrzohgjhh Dqgg H[shuwlvhh Iruu Ghvljqlqjj Furss Surwhfwlrqqjxlgholqhvv

Pesticide use is still much too often systematic on many crops. However, there is scientific consensus that many farmers could change their crop protection practices without putting their revenue in jeopardy. There is need for crop protection management systems that yield significantly lower pesticide consumption. For many crops such management systems are not available, although knowledge about the pathosystems exists. We present here two crop protection formal guidelines (Decision Workflow Systems, DeWS,) which were elicited and formalised using the Statechart (GrapeMilDeWS) and the coloured Petri nets (POD BLé) modelling languages. Elicitation and formal modelling helped the pathologists to ameliorate their design and provided a convenient computer ready format. Moreover, the main purpose of DeWS models is to provide an exhaustive specification, which can then be transferred. This permits large experimental networks to be created. Such networks are necessary to collect data about the behaviour of the pathosystem under low input management and to assess the DeWS robustness and efficiency. Finally DeWS are learning tools for the growers, development workers and for its original designers as well.