Organisation of vascular cambium during different seasons in some tropical timber trees

Abstract

The vascular cambium of Albizzia, Tectona, Terminalia, Calophyllum, Mangifera and Morinda was non‐storied while that of Dalbergia was semi‐storied. The ray initials were uniseriate in Terminalia and Calophyllum, both uniseriate and biseriate in Albizzia, Dalbergia, Mangifera and Morinda and were also multiseriate in Tectona. They were homogeneous in Albizzia and heterogeneous in the other species. The radial walls of cambial cells were always beaded, although beads were more prominent and closer to one another during periods of cambial dormancy than during activity. The fusiform initials were comparatively less vacuolated during dormancy/ least activity. When active, the fusiform and ray initials of all species, except Calophyllum, also showed multinucleate condition (2–10 depending on species). The proportion of ray initials to fusiform initials was almost constant throughout the year in all species.