Tuber micropropagation and direct shoot regeneration in Cyclamen persicum Mill abstract
Cyclamen is one of the most economically important ornamental pot plants in the world. It is traditionally propagated via seeds but seed propagation is usually associated with cultivar variation. In addition, hybrid seed production is expensive. Cyclamen has a tuber, which is a basal part that leaves start to come out of it. But daughter tuber does not generate from the main tuber. Therefore,tuber propagation of a superior plant could be a potential way of the multiplication of the Cyclamen. In the current study, two commercial cultivars have been examined for direct tuber propagation and the highest shoot regeneration. Tuber sections of aseptic seedling were cultured on 1/2 Murashige and Skoog (MS) basal medium supplemented with three different levels of BA (Benzyladenine). All the treatments contain NAA (Naphthalene acetic acid) as the source of auxin. Finally, the percentage of explants with tuber propagation, the average number of microtuber(s) per explant and the number of shoots regenerated from microtubers have been determined. No tuberpropagation and/or shoot
regeneration was observed on the control medium without hormones. The highest tuber micropropagation was observed in white flower cultivar with the mean number of 17 microtubers per tuber section on the media supplemented with 1 mgL-1of BA. The highest mean of shoot
regeneration on the microtubers was observed in the same media in the violet flower cultivar.Transfer of shoots to hormone-free medium results in the root formation. Developed plantlets were then acclimatized in the greenhouse and characterized by low percentages of somaclonal variation. Tuber micropropagation and subsequently the direct shoot
regeneration could eliminate unwanted variation associated with the callus induction in the common micropropagation methods of Cyclamen. The proposed propagation protocol will have a high commercial potential not only for clonal propagation, but also for cryopreservation and genetic transformation of Cyclamen as an ornamental (and medicinal) plant.