Root development of celery measured with minirhizotrons and core sampling

摘要

In a field experiment, the temporal and spatial root development of rooted celery (Apium graveolens L. var. secalinum) was measured using two sampling methods (minirhizotrons and core sampling). The roots expanded faster horizontally than vertically.Four weeks after planting only a few root intersections measured with the minirhizotron were found at a depth of 20 cm, and the maximum depth at harvest was 25 cm. High intersection counts at harvest were measured to a depth of 15 cm and to a horizontaldistance of 25 cm. A regression function was used to interpret the minirhizotron data. For each sampling date, this function was fitted to the number of observed intersections influenced by the depth and horizontal distance. Using the regression function, root length density measured by the core sampling method, was significantly correlated with the number of minirhizotron intersections calculated.