Studies on initial tissue culture techniques of mangrove tree species in Okinawa, Japan

本研究对分布于日本冲绳的几种红树树种进行了初步的组织培养技术研究。样品采集于冲绳岛木本植物木本植物、秋茄、木犀草科、木槿科树种，以及伊洛莫特岛白骨壤、马鞭草科白骨壤树种。诱导愈伤组织所用的材料是木兰、秋茄和柱花草的胎生种子，滨海牛膝的半胎生种子，丁香和白杨的种子。在愈伤组织培养中，将胎生种子切成5 mm厚的圆盘状颗粒，然后放在培养基上。将激动素作为细胞分裂素，2，4-D(2，4-二氯苯氧基乙酸)作为生长素，将愈伤组织诱导到MS培养基(Murashige and Skoog Medium，1962)。采用改良的灭菌方法结合乙醇和次氯酸钠溶液灭菌的方法几乎没有观察到污染。当激动素和2，4-D同时加入到愈伤组织诱导培养基中时，胎生种子的愈伤组织诱导率在胎生种子的各个生长阶段之间没有显著差异。以非共生幼苗的下胚轴为外植体诱导愈伤组织。继代培养是在胎生种子诱导愈伤组织的早期阶段进行的，因为后期的愈伤组织变得更硬，在继代培养基上生长不好。

In this study, attempts have been made to develop initial tissue culture techniques of several mangrove tree species distributed in Okinawa, Japan. The samples were collected from trees of Bruguiera gymnorrhiza, Kandelia candel, Rhizophora stylosa (Rhizophoraceae) and Hibiscus tiliaceus (Malvaceae) in Okinawa island, and trees of Avicennia marina (Verbenaceae) and Sonneratia alba (Sonneratiaceae) in lriomote island. Materials used for inducing calli were viviparous seeds of B. gymnorrhiza, K. candel and R. stylosa, semi-viviparous seeds of A. marina, and seeds of H. tiliaceus and S. alba. In the callus culture, viviparous seeds were cut in disc shaped particles in 5 mm thickness, then put on the media. Two regents of phytohormones, Kinetin as a cytokinin and 2, 4-D (2, 4-dichlorophenoxyacetic acid) as a auxin, were added for inducing calli to MS medium (Murashige and Skoog medium, 1962). Few contaminations were observed for using a modified sterilisation method combined with the ethyl alcohol and sodium hypochlorite solutions method.There was no significant difference in the rates of callus inductions between any growing stages of viviparous seeds of B. gymnorrhiza, K. candel and R. stylosa when both kinetin and 2, 4-D were added to the callus inducing media. Calli were induced from hypocotyls of non-symbiotic seedlings of H. tiliaceus. The subcultures were done at the earlier stages of inducted calli of viviparous seeds, because those calli at the later stages became harder, and not grew well on the subculture media.