In higher plants, reproductive phase takes place after completion of the vegetative phase which continues for a certain length of period. Floral initiation, which is the beginning of the reproductive phase, has been studied intensively mainly on photoperiodically inductive plants, but too many problems still exist to elucidate the mechanism of floral initiation. We believe this is likely due to the complexity of photoperiodic induction, and an investigation using day neutral plants will lergely eliminate this problem. McDaniel et al. (1992) also noted that flower initiation of day-neutral plants is instructive because the initiation is regulated by interactions among the various parts of the plant without a primary photoperiodic cue from the external environment.