African Journal of Biotechnology Vol. 4 (2), pp. 206-209, February 2005          
ISSN 1684–5315 © 2005 Academic Journals

Full Length Research Paper

Callus proliferation and somatic embryogenesis in cotton (Gossypium hirsutum L.)

Ikram-ul-Haq

Researcher Plant Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE), P. O. Box 577, Jhang Road, Faisalabad, Pakistan. E-Mail: ikramnibge@yahoo.com.

Accepted 14 July, 2004

Somatic embryogenesis and plant regeneration are fundamental to tissue culture biotechnology in cotton (Gossypium hirsutum L.) cv. Coker 312. Callus proliferation was considered best on MS_1a (2.0 mg/L NAA; 0.1 mg/L ZT; 0.1 mg/L KT) when 6 weeks old callus was cultured from MS_1b (0.1 mg/L 2, 4-D; 0.5 mg/L KT) medium, there is no need to select embryogenic calli for somatic embryogenesis, as all of them were converted to somatic embryos. NH₄NO₃ play an important role in differentiation of callus into somatic embryos but is lethal for embryos just after two weeks. However, KNO₃ is less efficient for somatic embryo induction but is best for embryo maturation. By this procedure 56.51% cotyledenary embryos were developed within 5 weeks. Of that, 82.05% cotyledenary embryos were developed not only into normal plantlets, but rooted simultaneously when cultured on MS (with 0.05 mg/L GA₃) medium. A complete plant of Cocker-312 could be regenerated through somatic embryogenesis within 4 to 5 months.

Key words: Gossypium hirsutum L,plant regeneration, Coker 312, callus induction, somatic embryogenesis, in vitro regeneration.