An ultrastructural study of the development of resin canals and lacquer secretion in Toxicodendron vernicifluum (Stokes) F.A.Barkley

Raw lacquer is a natural resin obtained by tapping the secondary phloem of oriental lacquer trees (T. vernicifluum), and the secretory cells of the resin canals play an important role in raw lacquer production. The objective of this study was to perform a detailed analysis of the anatomy and ultrastructure of the secretory cells, to investigate the structural characteristics and ontogeny of secretory cells, and study the synthesis and secretion of raw lacquer. This cytological study on the structure of secretory cells and the secretion of raw lacquer were investigated using alight microscope (LM) and transmission electron microscope (TEM).The results showed that the resin canals was formed by the initial cells of secretory cells through schizogeny. Secretory granules with monofilm were shaped by Golgi bodies and transported to the plasma membrane. Thereafter, the granules were fused with the cell membrane, and the interior flocculent materials were released to the periplasmic space and spread to the resin canals through the cell walls of secretory cells. Finally, the cells fused and gathered in the lumen to form raw lacquer. The present study offers detailed information on the ultrastructure of secretory cells and the process of raw lacquer secretion.