In vitro micropropagation of a novel non-flowering radiation mutant of Platanus × acerifolia Willd.

An efficient in vitro micropropagation system for Platanus × acerifolia ‘F03’, a radiation mutant that has not flowered for 19 yr, has been established. Axillary buds were used as explants. After sprouting on Murashige and Skoog medium (MS) supplemented with 0.3 mg·L −1 6-benzylaminopurine (6-BA) together with 0.05 mg·L −1 α-naphthaleneacetic acid (NAA), the best medium for multiplication and elongation was MS basal medium supplemented with 0.1 mg·L −1 6-benzylaminopurine and with a multiplication rate of 3.43 ± 0.57. Plantlets over 1.5 cm could root on McCown Woody Plant Medium (WPM) supplemented with 0.01 mg·L −1 α-naphthaleneacetic acid and 7.0 g·L −1 agar with an ideal rooting rate and transplanting survival rate of 100 ± 0%. The optimum survival rate was possible when trays were covered with a thin plastic lid for more than 14 d. After transplanting, air humidity and temperature were crucial for young plant survival. The system established here could serve as a pathway for commercial production of the line and provide sterile leaf explants for regeneration and further genetic improvement of the species.