Sara Zakizadeh, Behzad Kaviani and Rasoul Onsinejad
Day length is an important factor effective on plant growth and development. The present study describes the effects of different photoperiods (16-8, 14-10 and 12-12 h light/dark) on some growth characters of Hippeastrum johnsonii using bulblets cultured on MS basal medium. Explants were bulblets. In all cases, 16-8 h light/dark was more effective. Maximum bulblets diameter (3.15 cm), leaf length (9.80 cm), root number (2.25), root length (2.18 cm) and longest root length (2.70 cm) were observed in explants treated with 16-8 h light/dark.
