Effets des opérations de travail du sol sur la fragmentation des racines du chardon des champs (Cirsium arvense).

The reduction of herbicide use and tillage favors perennial weeds, which are highly problematic in field crops. These species develop storage organs capable of regenerating new plants (vegetative multiplication). Tillage has been identified as a management lever to be optimized to reduce perennial weeds but its effects are poorly understood. In this study, the effect of tillage tools on the fragmentation of Cirsium arvense creeping roots was analyzed. The length of the root fragments produced was measured : the rotary harrow produced the smallest fragments (3.7 cm on average), the plough the longest fragments (12.7 cm) and the other tools fragments of intermediate length (8-10 cm). These results will be used in cropping system models to understand the effect of tillage methods on perennial-weeds.