3.1. Effect of photoperiod on vegetative growth and flowering ofTDCAll plants that were grown under 7 types of photoperiods even-tually formed visible floral buds, although the time to first floweropening was different. The longer the photoperiod was, the earlierthe plants flowered (Fig. 1). The plants that were exposed to pho-toperiods of 14 h, 16 h, 18 h, 20 h and 24 h (day-length) floweredsignificantly earlier than those plants that were treated under 10 hand 12 h (Table 1). Thus, TDC could be defined as a LD plant, of whichthe critical day-length was 14 h. Additionally, the longest time tofirst flower opening was 279.0 d under 10 h, and the shortest timewas 247.8 d under 24 h.At the time of first flower opening, no significant differences inthe crown diameter, flower number per inflorescence, and scape