Production of fertile somatic hybrid plants between Oriental hybrid lily and Liliumxformolongi.

Somatic hybridizations via electrofusion were performed in combinations of Oriental hybrid lilies (cvs. Acapulco and Shirotae) and Liliumxformolongi hort. (cv. Hakucho). Electrofusion-treated protoplasts divided only under nurse culture. The divided protoplasts grew into calli on the culture medium containing picloram, and the calli were then transferred to the hormone-free culture medium for induction of plant regeneration. The regenerants were transferred to a greenhouse, and were grown until the flower stage. In the fusion combinations of Acapulco + Hakucho and Shirotae + Hakucho, four regenerants apparently showed different morphological features compared with their parents. The results of molecular analyses by means of cleaved amplified polymorphic sequences markers and flow cytometry confirmed that these regenerants were somatic hybrid plants. Furthermore, we examined the stability of the morphological features of the hybrids in the next generations. This is the first report to describe the successful realization of Lilium somatic hybridization via protoplast fusion.