Proceedings of the XLV Italian Society of Agricultural Genetics - SIGA Annual Congress

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

Poster Abstract

TISSUE CULTURE AND A. RHIZOGENES TRANSFORMATION IN SEVERAL ORNAMENTAL LIMONIUM

RUFFONI B., SEMERIA L., DOVERI S., SAVONA M., ALLAVENA A.

Istituto Sperimentale per la Floricoltura, Corso Inglesi 508, 18038 Sanremo

Tel 0184 667251, Fax 0184 695072

istflori@sistel.it

organogenesis, somatic embryogenesis, hairy roots, plant architecture

Within the genus Limonium (Plumbaginaceae) many species, with interesting ornamental value to be commercialised as fresh and dried cut flower, were identified. In the frame of a National Research Project, devoted to valorisation of Limonium for ornamental purposes, a screening of the morphogenetic potential of the most promising species has been carried out.

A) A micropropagation protocol has been established for 10 species, and shoot regeneration has been induced from leaf discs in the presence of BA. Severe bacterial contamination were found, when the tissue of the basal part of the plant (rosette), carrying meristems, was cultivated in vitro. This problem has been overcome by using immature floral scapes as source of explants. In presence of 2 iP (5 mg/l) or Zeatine (0,5-1 mg/l) buds were induced from immature flowers. The derived shoots were cloned, rooted and transferred to the greenhouse. No somaclonal variation was observed during growth in vivo.

B) In presence of 2,4D (1 mg/l), the tissues of 2 species showed callus and globular somatic embryos formation. Torpedo-shape somatic embryos developed after transfer on medium without growth regulators. Up to 60 plantlets was produced per Petri dish. Also in this case the plants transferred to the soil showed phenotypic uniformity.

C) After co-cultivation with A. rhizogenes wild type strain 1855 the induced hairy roots regenerated new shoots. PCR confirmed the presence of rol C gene and the absence of vir genes in plants of some regenerated clones. The transformed clones showed a severe reduction of the plant size and produced miniaturised floral scape.

The potential of the tissue culture approaches will be discussed in view of the genetic improvement of the Limonium for ornamental pourposes.