African Journal of
Plant Science

  • Abbreviation: Afr. J. Plant Sci.
  • Language: English
  • ISSN: 1996-0824
  • DOI: 10.5897/AJPS
  • Start Year: 2007
  • Published Articles: 718

Full Length Research Paper

Influence of nutritional media and photoperiods on in vitro asymbiotic seed germination and seedling development of Dendrobium aqueum Lindley

S. Parthibhan1, J. H. Franklin Benjamin2, M. Muthukumar1, N. Ahamed Sherif1, T. Senthil Kumar3 and M. V. Rao1*   1    
Department of Plant Science, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India. 2Botanical Survey of India, Southern Regional Center, TNAU campus, Coimbatore-641 003, Tamil Nadu, India. 3Department of Industry University Collaboration, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India.
Email: [email protected]

  •  Accepted: 25 September 2012
  •  Published: 30 November 2012

Abstract

Dendrobium aqueum Lindley is an epiphytic orchid decreasing in nature owing to environmental disturbance and inherent lower germination rates of mature seeds. To conserve this species, in vitro asymbiotic media and photoperiod screening were experimented. Twenty asymbiotic orchid seed germination media were examined to get the optimal medium for germination and seedling development under 16/8 hrs photoperiod. Highest seed germination occurred in 1/2 MS medium (93.41%) followed by mMS (91.04%) and m ½ MS (90.23%) in 6 to 7 weeks. The biggest protocorms were observed in MS medium (788.8 µm) followed by ½ MS (615.60 µm). The yellowish embryos during germination exhibit varied colours from yellow to pale green, dark green, yellow, brown, black and white. MS, ½ MS, mMS, ½ mMS, and ¼ MS media only promote fully developed seedlings within 126 to 143 days. The influence of five different photoperiods with four media was also examined separately. 24/0 hrs (L/D) photoperiod provide highest germination (97.75%) on MS followed by ½ MS (96.01%). Dark Photoperiod 0/24 h (L/D) supports up to protocorm stage but with poor seedling growth. The well rooted seedlings were hardened and successfully reintroduced in its natural habitat with 56% survival rate.

 

Key words: Dendrobium aqueum, asymbiotic seed germination, nutritional media, photoperiods, seedling development, reintroduction.