Anatomy of the stems of seedling palms

Abstract

The anatomy of stem in 19 species of seedling plams is described in representative species from all the sub-families of Palmae, except Nypoideae and Phytelephantoideae. Morphologically, the stem of juvenile palm is an obconical structure, and that of the adult palms mostly solitary columnar. The cortex of stems in young palms is very wide, and often exceeds the diameter of central cylinder in contrast to very narrow cortex in adult palms. The number of vascular bundles increases several-times from the lower to the upper level of juvenile axis, whereas the number of bundles more or less, remains the same at different levels of the stem in adult palms. There is a wide meristematic zone towards the tip of axis and just below the bases of the young leaves which is responsible for widening of the seedling stem until it attains the mature stem diameter. The xylem of central vascular bundles in young palms is mostly composed of protoxylem elements but, in adult palms, they include well-developed metaxylem vessels. The central ground parenchyma is compact in young palms, spongy and lacunose in adult palms.