Anatomical study of racosperma (ex-acacia) mangium tissues cultured in vitro

Abstract

In order to achieve adventitious shoot regeneration from young tissues of Racosperma mangium, several combinations of growth regulators were tested. Kinetin (KIN) and a-naphthalenacetic acid (NAA), thidiazuron (TDZ) and NAA or indole-3-butyric acid (IBA), 4-CPPU and 2,4-dichlorophenoxyacetic acid (2,4-D) were added to basic medium composed of MS salts, MS vitamins and 3% sucrose. Sections of hypocotyls and cotyledons of young seedlings were cultivated on these media. Calli developed on different media and, after t\vo to three months, some of them regenerated organized structures. Histological studies revealed hypertrophy and hyperplasy of medular and cortical parenchyma cells of hypocotyl and cotyledon parenchyma. Formation of meristetnatic cells and traqueary elements from parenchyma was observed during in vitro culture. In some cases, nodules oftraqueary elements were formed. Tlie highest differentiation into meristematic cells was found in cotyledon tissues cultured on 4-CPPU (8.07 UM) and 2,4-D (1.13 /zMJ. © 2000, Parana Institute of Technology Publication.