LEAF DISSYMMETRY AND VEIN GROWTH FIELD - THE CASE OF THE TROPAEOLUM LEAF VEINS

The growth of the vein system of the leaf of Tropaeolum peltophorum wa s studied (i) at the vein level (analysis of the growth kinetics and o f the growth field of the 7 primary veins) and (ii) at the limb level (comparison of the growth of the veins). The vein growth kinetics depe nd on the position of the vein on the leaf: there is a proximal / dist al gradient and a bilateral gradient of the growth parameters (= varia tion of the temporal organization of the kinetics). The growth field o f the veins (= local growth pattern) is also dependent on time and on vein position. Specific correspondences exist between singular points of the global growth curves (V-max,Gamma(min)) the variations of the g rowth field and the vein position. The spatio-temporal organization of the vein system growth is then characterized by positional variations of kinetic order which show the existence of a real morphogenetic dis symmetry.