Research on vitro regeneration of cotton (Gossypium hirsutum L.)

This study was conducted to determine the effects of different media on plant regeneration from various explants of different cotton varieties through organogenesis and somatic embriyogenesis. Anthers of Çukurova 1518, Coker 312, Nazilli 84, Erşan 92, Maraş 92, Adana 98 and Sayar 314 cotton varieties were used for anther culture. As the source of explant for organogenesis, shoot tips and cotyledon nodes excised from 2 or 5 weeks old in vitro plants of Çukurova 1518, Coker 312 and Erşan 92 varieties were used. For the somatic embryogenesis part of the study, hypocotyl explants excised from 7 days old in vitro plants and 14, 21 and 28 days old immature zygotic embryos were used. Different callus induction rates from the anthers were obtained depending on the genotypes and media. The highest callus induction rates were obtained from the anthers of Adana 98 and Erşan 92 cotton varieties on MS medium with 0.1 mg/1 kinetin and 0.1 mg/1 2.4D or 0.1 mg/1 kinetin and 0.5 mg/1 2.4-D whereas plant regeneration was not obtained from the calli transferred to different regeneration media. For the organogenesis study, it was determined that the highest number of shoots per explant were obtained from shoot tips of Çukurova 1518 and Erşan 92 cultured on MSB (MS medium with vitamins of B5 medium) with 2 mg/1 kinetin and 2 mg/1 BAP. It was found that the healthy plantlets with vigorous root system were obtained from the explants cultured hormone free MSB medium in spite of the the lower number of shoots. In the somatic embryogenesis part of the study, embryogenic calli were obtained on MSB medium with 0.1 mg/1 kinetin and 2 mg/1 NAA, and somatic embryos were obtained from embryogenic calli cultured on hormone free liquid MSB medium. Key Words: Gossypium hirsutum L., anther culture, organogenesis, somatic embryogenesis n f