Evaluation of the population dynamics of annual weeds to test integrated weed management at a farming system level

Abstract

In the Netherlands, several research projects are being carried out to develop sustainable farming systems that are characterized by markedly reduced inputs of pesticides and fertilizers. In these long-term projects, weed management appeared to be a serious constraint on the introduction of sustainable agriculture. A method to monitor the population dynamics of annual weeds in crop rotations and to compare the results for farming systems is presented. Preliminary results show that, after 3–5 years, weed densities tended to be higher in the integrated systems than in the conventional reference systems. This trend in the population dynamics of weeds is discussed with respect to differences in inputs in weed management (active ingredients), possible effects on crop yields and improved strategies to prevent increases in weed abundance.