Action of gibberellic acid in effecting phase shifts of the circadian leaf-movement rhythm of a cotton plant,Gossypium hirsutum

摘要

Pulses of gibberellic acid (GA3) offered at various phases of circadian leaf-movement rhythms in the cotton plant,Gossypium hirsutum, effected advance phase shifts of varying magnitude. Neither the quality nor the amount of these phase shifts was altered by the background illumination, suggesting an apparent absence of synergistic action of the light and gibberellic acid.