B. Nesi, S. Lazzereschi, S. Pecchioli, A. Grassotti, G. Burchi, M. Cardarelli, C.M. Cardona Suarez, G. Colla
In breeding programs of ornamental crops, interspecific hybridization is one of the most important way to introduce new genetic variation. The sexual barriers hampering interspecific hybridization have been distinguished into pre-fertilization and post-fertilization barriers. A breeding program on Lilium was carried out in Symplitaly project to overcome barriers of interspecific incompatibility and to originate hybrids with new ornamental traits (shape, size and colour of flower) and suitable to the Italian environment (tolerance to low temperatures and scarce light). Several crosses among Oriental hybrids, L. longiflorum OT hybrids, LA hybrids, Asiatic hybrids and wild species were made by using cut-style method. Ovary and ovule culture has been applied to overcome post-zygotic barriers. Fourteen days after pollination ovaries were cut and in vitro cultivated using two different substrates respectively with NAA 1 mg/L and IAA 0.5 mg/L. After 50-60 days more swollen ovules were taken out from ovary and cultivated on two substrates, with IBA 0.5 mg/L and NAA 0.1 mg/L, for 120-180 days. To confirm the hybrid origin of new bulblets, RAPD and SSR markers methods have been tested.
According the project, in vitro bulblet propagation of Lilium has been studied using an automated balloon type bubble bioreactor. In fact scaling-up in bioreactors and reduction in manual handling could provide an efficient and economic system for in vitro multiplication of bulb plants. Two different culture methods were compared: continuous immersion and temporary immersion in liquid medium (ebb and flood system). Results revealed that morphological traits and biomass accumulation were more efficient when culturing was performed under continuous immersion.
Nesi, B., Lazzereschi, S., Pecchioli, S., Grassotti, A., Burchi, G., Cardarelli, M., Cardona Suarez, C.M. and Colla, G. (2014). DEVELOPMENT, SELECTION AND PROPAGATION OF INTERSPECIFIC HYBRIDS OF LILIUM. Acta Hortic. 1027, 155-163
DOI: 10.17660/ActaHortic.2014.1027.16
ovary and ovule culture, molecular marker, liquid culture, bioreactor

Acta Horticulturae