对极小种群物种瑞丽茜树Fosbergia shweliensis的组织培养和离体保存技术进行研究。结果表明,以种子苗茎尖和成年植株幼嫩茎段为外植体均能诱导无菌苗,适宜的启动培养基分别为MS + 2 mg·L-1 6-BA + 0.2 mg·L-1 NAA + 3%蔗糖和MS + 3 mg·L-1 6-BA + 0.1 mg·L-1 NAA + 3%蔗糖,增殖率达3~4倍。诱导生根的适宜培养基为1/2MS + 1 mg·L-1 IBA + 2%蔗糖,生根率100%,移栽成活率90%以上。完整试管苗在培养基1/2MS + 3% 蔗糖,12~15 ℃条件下可缓慢生长,继代时间可延长为18~24个月一次,实现了该物种的离体保存。
The techniques of tissue culture and in vitro conservation of Fosbergia shweliensis were studied. The results showed the aseptic plantlets could be obtained from stem tip of seedlings and stem node explants of F. shweliensis. Their suitable initial medium was MS medium with 3.0 mg·L-1 6-BA, 0.1 mg·L-1 NAA and 3% sucrose, and MS medium with 2.0 mg·L-1 6-BA, 0.1 mg·L-1 NAA and 3% sucrose, respectively. The multiplication rate was up to 3—4 times. The best rooting for plantlets occurred on 1/2MS medium with 1.0 mg·L-1 IBA and 2% sucrose, the rooting rate was 100%. The survival rate of aseptic plantlets transplanted after hardening was more than 90%. The tube-test plantlets could grow slowly on 1/2MS medium with 3% sucrose at 12—15 ℃, in consequence subculture period was lengthened to 18—24 months. The success of rapid propagation and in vitro conservation supported the further research, development and utilization of this species.
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