New technique for cut flower production from bulbils of the Asiatic hybrid lily (Lilium×elegans Thunb.)

- Production of cut flowers starting from bulbils of L.×elegans was investigated.
- About 400 mg in fresh weight of bulbils were harvested 40-50 days after flowering.
- Bulbils were treated with a sequential treatment 14 to 20 days each at 5 °C-15° or 20 °C-5 °C.
- Cut flowers with two to three flowers on a strong stem were produced in less than year.
- Total production involved plug production phase followed by forcing phase of small bulblets.

Generally, two to three years are required to produce bulbs of Lilium×elegans Thunb. from bulblets for forcing in the greenhouse. During the bulb production phase in the field, virus infection often lowers the quality of bulbs. The objective of this research was to investigate the feasibility of forcing bulbils to produce plants with two to three flowers on a stem longer than 60 cm. Uniform bulbils of L.×elegans produced naturally from the axils of leaves were used to investigate the effect of maturity and size of bulbils, plant growth regulator treatment, sequential or constant temperature treatments given to bulbils, and temperature, and high light irradiance treatments upon scaly leaf emergence on growth and flowering. Further changes in shoot apex size as influenced by sequential and constant temperature treatments and soluble carbohydrates as affected by temperature and plant growth regulators were investigated. Cut flowers of Asiatic hybrid 'Beni no Mai' with two to three flowers and strong 60 cm stems were produced in less than a year when mature bulbils weighing about 400 mg harvested 40 to 50 days after flowering, are treated with a sequential temperature treatment (SEQ CD) 14 to 20 days each at 5 °C-15° or 20 °C-5 °C. This long growing period can be divided into two phases. The first phase, similar to plug production, occurs from potting the treated bulbils, to senescence of scaly leaves, and to shoot emergence and lasts about 200 to 230 days. The second phase proceeds from shoot emergence to flowering and requires 90 to 100 days. The first phase could employ plug production technology by growing plants pot to pot, and the second phase could be considered typical greenhouse forcing. The observed increase in the number of flowers could result from the increased shoot apex. This procedure eliminated the bulb production phase in the field and reduces the time from propagation to flowering by one to two years.