Abstract
Delaying anthesis by dark treatment in Phalaenopsis 'Yukimai No.24' was investigated. Plants kept at 20°C in the dark survived for 80 days, whereas most of plants kept at 10°C in the dark did not survive for 20 days. Plants exposed to light bloomed on Feb. 16, 1999, whereas the plants which kept at 20°C in the dark during 20, 40, 60, and 80 days bloomed on Mar. 15, Apr. 3, Apr. 28, and May 15, respectively. Although the length of stalk and flower size were unaffected by the 20°C dark treatments, the number of flowers in the 80-day treatment was reduced slightly. These results indicate that delaying anthesis in Phalaenopsis is possible by the dark treatment.
