Abstract

Ikram-ul-Haq

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 MS1a (2.0 mg/L NAA; 0.1 mg/L ZT; 0.1 mg/L KT) when 6 weeks old callus was cultured from MS1b (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, KNO 3 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.