Organogenesis of anther-derived calluses in long-term cultures of Oenothera hookeri de Vries

Anthers of O. hookeri containing uninucleate microspores were cultured, in vitro, at 25°C (16 hours photoperiod) on solid MS medium. After 10–15 days, on media with 2,4-dichlorophenoxyacetic acid, 1-naphthaleneacetic acid and 6-benzylaminopurine, anthers developed friable calluses. After unsuccessful treatments on embryogenic-and/or organogenic-induction media, calluses were placed on a hormone-free MS medium for 24 months with routine transfers every 3 weeks. After this period, the calluses developed buds and subsequently plants. Ro generation plants, were morphologically distinct.