VEGETATIVE DISPERSAL OF ALLIUM NEAPOLITANUM

Abstract

Vegetative propagation and dispersal were studied in attached and detached increase bulblets of Allium neapolitanum. The bulblets were sown in 3 positions (upright, horizontal, and inverted) at various depths, and the directions of the contractile roots and movement in the soil were calculated. A thick contractile root develops spontaneously from the base of the bulblet, irrespective of planting level, even at normal depth. The root is ageotropic and its direction is chiefly determined by the bulblet position. It generally develops at a plane perpendicular to the longitudinal axis of the bulblet. Thus, in upright and inverted bulblets, the root is horizontal, while in horizontal ones it may grow in various directions but always on the plane perpendicular to the axis of the bulblet. Depth has a marked effect on the direction of the contractile roots, diverting them from their original route (upwards in deep‐seated plants and downwards in shallow ones). Thus, the vegetative dispersal of Allium neapolitanum is tridimensional, within definite soil levels.