Imb (Philodendron bipinnatifidum), has a large distribution in Brazil. It produces aerial and subterranean roots. This study presents the anatomical description of the mature prop roots and analyzes the apical root meristem region (1.0-3.0mm). The roots were brown except for the apical portion, which was white. Root segments measuring 0.3cm in length were excised from aerial roots for a length of 1.2cm starting from the root tip. Another 0.5cm segment from the suberized region of the root, was also excised. The segments were fixed in Karnovsky solution, dehydrated in a graded ethanol series (10 to 100%), and then embedded in glycol methacrylate resin. The apical root meristem region (1.0-3.0mm), presented a many-layered root cap that consisted of sinuous anticlinal cell walls, compactly arranged. The protodermis was uniseriated. The resin ducts arose schizogenous among the fundamental meristem cells. The central cylinder exhibited conspicuous lobes. In suberized region, the epidermis was substituted by a stratified cork. The outer part of the cortex was arranged in relatively bigger intercellular spaces while the inner cortex presents 4 and 5 layers of cells arranged in radial files. The resin ducts and the secretory idioblasts occurred among cells of the cortical parenchyma. The central cylinder exhibited anomalous organization of vascular tissues with conspicuous lobes and a pith region was absent.
imb; Araceae; anatomy; aerial roots; resin ducts
