In vitro plant regeneration of caper (Capparis spinosa L.) from floral explants and genetic stability of regenerants

A new technique to regenerate caper plants (Capparis spinosa L. subsp. rupestris) starting from flower explant is reported. In vitro plant regeneration was attempted using stigma, anthers and unfertilized ovules of unopened flowers collected in the field. Plant regeneration was achieved from unfertilized ovules on MS medium supplemented with 88 mM sucrose and 13 mu M 6-benzyladenine (BA). New individuals obtained from unfertilized ovules were used as source material for micropropagation and multiple shoots were obtained on MS medium supplemented with the adeninic cytokinin BA and the auxin indole-3-butyric acid (IBA). Explants obtained in micropropagation step were used for rooting step under several treatments. The best results (100% of rooted explants) were obtained when explants were dipped for 10 min in 50 mu M IBA solution and successively maintained in growth regulator free medium. New plants were vigorous, of good quality and presented phenotypic characters similar to mother plants. Furthermore genetic stability of regenerants was verified through flow cytometric analysis and two different DNA-based techniques.