Rooting depth and spatial arrangement of roots in winter wheat
Masse, J.T.rdieu, F.C.lnenne, C.
Developments in agricultural and managed forest ecology 4(24): 480-486
The kinetics of rooting depth and spatial arrangement of winter wheat roots were studied in field conditions. Rooting depth was observed with a minirhizotron and spatial arrangement by root mapping. Distances between each point in the soil and the nearest root were calculated directly from 4 superimposed horizontal maps. The rate of root extension was related to accumulated thermal time (1,2 mm per degrees C. day). In favourable soil structures, maximum rooting depth began in very early. The soil profile was intensely colonized from the beginning of stem elongation: more than 80% of plane areas were at a distance of less than 4 cm from the nearest root except at 90 cm deep. The depressive effect of late sowing dates on root contact frequency had disappeared at anthesis.