ANATOMICAL STUDY ON ROOT FORMATION IN <em>ACACIA</em> <em>MANGIUM</em> STEM CUTTINGS

Abstract

The root formation in 1- y - old Acacia mangium stem cuttings was first detected in the phloem region, very near to the cambial layer and in between the actively elongated medullary rays. The cortical cells were the first to divide and then the medullary rays broadened. Subsequently groups of smaller cells which had meristimatic capability appeared in the phloem region. These smaller cells then developed into root initials. After further cell division, the root initial together with the newly developed vascular elements, formed the compact spherical root primordium, which grew outward through outer layers to become adventitious roots.