Bulblet regeneration from ex vitro root explant in lily hybrids

The influence of growth regulators on in vitro bulblet formation from ex vitro roots was Studied in asiatic and oriental hybrids of Lilium. The root segments (3-4 mm) isolated from the middle zone of 2-3 cm ex vitro root were cultured on Murashige and Skoog (MS) medium containing 1 or 1.5 mg/dm(3) naphthalene acetic acid (NAA) and/or benzyladenine (BA). Bulblets were not produced in the presence of NAA and BA alone. A significant increase in the per cent explants producing bulblets was observed with 1.5 mg/dm(3) NAA and 1 mg/dm(3) BA. Maximum number of bulblets and average fresh weight per bulblet was observed with 2 mg/dm(3) NAA and 1.5 mg/dm(3) BA after 90 days of culture. No differences were found among cultivars in bulblet regeneration of explant or bulblet number although more weighty bulblets occurred in cv. Apeldoorn. About 82% bulblet survival was recorded in coco peat after 30 clays of transfer to pots.