Relationship between starch accumulation and organ development at the different growth stages of callus in Kihada (Phellodendron amurense Rupr.)

Abstract

Microscopic observations of Kihada (Phellodendron amurense) callus revealed a strong correlation between starch accumulation and organ development. The starch accumulation started before any observable organ development and was prominent in cells which ultimately gave rise to organ primordia. A large amount of starch accumulation was observed in the three- or four-celled proembryo-like structure (PLS) organization of callus cultured on MS media supplemented with BAP plus 2,4-D. Two-celled PLS showed low performance for accumulation of starch. No starch accumulation was observed in globular and heart-shaped embryo-like structure ELS organization. During shoot primordium development, a decrease in the starch content of the cultured tissues was found, indicating the utilization of the glucan in the organogenic process. Starch granules disappeared with the development of the meristematic dome and leaf primordium and also started to disappear gradually with the development of cell walls and the tracheary elements. Copyright © 2006 The Japanese Society for Plant Cell and Molecular Biology.