Journal of
Medicinal Plants Research

  • Abbreviation: J. Med. Plants Res.
  • Language: English
  • ISSN: 1996-0875
  • DOI: 10.5897/JMPR
  • Start Year: 2007
  • Published Articles: 3793

Full Length Research Paper

Micropropagation and in vitro flowering of Dendrobium wangliangii: A critically endangered medicinal orchid

Dake Zhao1,2, Guangwan Hu1, Zhiying Chen1, Yana Shi3, Li Zheng4, Anjun Tang5 and Chunlin Long1,6*
1Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences, 650201 Kunming, China. 2Chinese Academy of Sciences, 100049 Beijing, China. 3Institute of Medicinal Plants, Yunnan Academy of Agriculture Science, 650233 Kunming, China. 4College of Horticulture and Landscape, Yunnan Agricultural University, 650201 Kunming, China. 5College of Life Science, Chongqiong Normal University, 400047 Chongqiong, China. 6College of Life and Environmental Sciences, Minzu University of China, 100081 Beijing, China.
Email: [email protected]

  •  Accepted: 03 April 2012
  •  Published: 25 July 2013

Abstract

Dendrobium wangliangii is seriously threatened because of anthropogenic and environmental pressures. A protocol with seed asymbiotic germination was developed to conserve the orchid in vitro. The germination rate was 92% under 16/8 h (light/dark) photoperiod after 240 days from hand-pollination in a modified medium. Polyembryony was founded in D. wangliangii, with a percentage of 0.87%. Half MS promoted the protocorms proliferation well, with the protocorms differentiated at the frequency of 28.79% when cultured on half MS, supplemented with 2 mg L-1 6-benzylaminopurine (BA) and 0.1 mg L-1naphthaleneacetic acid (NAA). Additives, especially 100 ml L-1 coconut milk (CM), improved the protocorm differentiation greatly but led to a lethality of 49.92%. The pretreatment of 1 mg L-1 GA3 for 15 days, after inoculated to the medium amended with 2 mg L-1 BA, 0.1 mg L-1 NAA and 100 ml L-1 CM, increased the differentiation to 54.68%. The combination of 2 mg L-1 BA, 0.1 mg L-1 NAA, and 100 ml L-1 CM also showed an efficient role in adventitious bud multiplication. CM effectively controlled the albino phenotype. In addition, inflorescence induction (100%) was produced with 2 mg L-1 1-phenyl-3-(1, 2, 3-thiadiazol-5-yl)-urea (TDZ) and the best flower development was obtained with 0.3 mg L-1 paclobutrazol (PP333), and 0.5 mg L-1 NAA.

 

Key words: Dendrobium wangliangii, micropropogation, asymbiotic germination, adventitious buds multiplication, polyembryony, in vitro flowering.