Systematic significance of the petiole vascular bundles types in Dipterocarpus Gaertn. F. (Dipterocarpaceae)

A comprehensive survey and descriptions on the petiole anatomy was undertaken on 16 Dipterocarpus species to investigate variations in vascular bundle structure that may be useful in classification and identification of species. All species have a complex structure of vascular bundles consisting of several closed rings of bundles. Five different types of vascular bundles i.e Type 1, 2, 3, 4 and 5 in the petiole transverse sections were found, based on the arrangement and system of vascular bundles strand. Types of vascular bundles were determined and suggested for easy reference. Results showed that the types of vascular bundles can be used for grouping of species in Dipterocarpus and also helping in species identification