African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12496

Full Length Research Paper

Laboratory studies on vegetative regeneration of the gametophyte of Bryopsis hypnoides Lamouroux (Chlorophyta, Bryopsidales)

Naihao Ye1*, Hongxia Wang2, Zhengquan Gao3 and Guangce Wang2
  1Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences,Qingdao 266071, China. 2Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China. 3School of Life Sciences, Shandong University of Technology, Zibo 255049, China.  
Email: [email protected]

  •  Accepted: 14 January 2010
  •  Published: 22 February 2010

Abstract

 

Vegetative propagation from thallus segments and protoplasts of the gametophyte of Bryopsis hypnoides Lamouroux (Chlorophyta, Bryopsidales) was studied in laboratory cultures. Thallus segments were cultured at 20°C, 20 μmol photons m-2s-1, 12:12 h LD); protoplasts were cultured under various conditions, viz. 15°C, 15 μmol photons m-2 s-1, 10:14 h LD; 20°C, 20 μmol photons m-2 s-1, 12:12 h LD; and 25°C, 25 μmol photons m-2 s-1, 14:10 h LD. Microscope observation revealed that the protoplast used for regeneration was only part of the protoplasm and the regeneration process was complete in 12 h. The survival rate of the segments was 100% and the survival rate of protoplasts was around 15%, regardless of culture conditions. Protoplasts were very stable in culture and were tolerant of unfavorable conditions. Cysts developed at the distal end or middle portion of gametophytic filaments under low illumination (2 - 5 μmol photons m-2 s-1), the key induction factor. Cysts formed several protoplast aggregations inside or the cyst as a whole detached directly from the matrix and all the units were able to develop directly into new gametophytes. Regeneration directly from protoplasts and thallus segments were also discovered in the field. A relatively completed life history of B. hypnoidesis established with newly discovered propagation methods, namely protoplast regeneration.

 

Key words: Bryopsis hypnoides, protoplast, thallus segment, propagation method, life history.

Abbreviation

 

Abbreviations: LD, Light/dark; FFB, free floating branch; MA, macrothallus.