Risks of post-emergence weed control strategies in sugar beet: development and application of a bio-economic model

In The Netherlands, new farming systems have been developed that combine environmental sustainability with technical feasibility. Adoption of these new production strategies in practice seems to be hampered by their association with high levels of risks. In the case of weed control in sugar beet the risks of the new techniques concern manageability and probability of success in relation to meteorological aspects. The Bio-Economic model on STrategy choice in Weed control IN Sugar beet (BESTWINS) allows an efficient and consistent comparison of strategies ranging from conventional to environmentally friendly with respect to risk. Risk is calculated by implementing the various strategies under a range of meteorologically determined conditions. Risk is measured by the statistical value distributions of characteristic parameters of the weed control strategies; e.g. cost and required labour and active chemical ingredient. Calculations show that more sustainable strategies do not necessarily imply an increase in risk. Labour requirements for manual weeding are generally higher than for the biological strategy, but under exceptional conditions (95% point) other strategies show high requirements as well. Intensive tractor use increases labour requirements for strategies with row spraying combined with mechanical techniques. ©