Studies on the Flowering in Marguerite

Chrysanthemum frutescens L.

Abstract

1) Marguerite is a plant requiring cold temperature for flower formation. Rooted cuttings do not initiate flower buds if they are kept at high temperature such as 30°C regardless of the difference in day-length, but they initiate flower buds at 20°C with short day-length.
2) Cold temperature is the main cause for flower bud formation, but short day-length also enhances it to a less degree.
3) Flower bud differentiation occurs at 20°C under short day condition of more than 40 days.
4) Long day-length promotes flowering better after low temperature treatment than after short day-length.
5) Gibberellin effects, to a slight degree, the flowering of the plant which has received short day-length for 50 days.