Replacement of chilling requirement in seeds of Ruellia humilis by gibberellic acid.

Gibberellic acid (GA3) completely replaced the chilling requirement of intact, dormant seeds of Ruellia humilis. At 30° 100 and 1000 mg/l completely replaced the chilling requirement, while in seeds germinated at 25° 100 mg/l GA3 was ineffective but 1000 mg/l entirely replaced the after-ripening requirement at low temperature.