Micropropagation and shoot regeneration of Cistus creticus ssp. Creticus.

Cistus creticus L. ssp. creticus is a medicinal aromatic shrub native in Crete (Greece). The protocol described in this paper provides optimal levels of growth regulators required to obtain high regeneration rates of Cistus in vitro. Micropropagation has been achieved through rapid proliferation of shoot-tips on Murashige and Skoog (MS) basal medium supplemented with 0.2 mg l-1 6-benzylaminopurine (BAP). After four weeks shoots were transferred to MS medium without growth regulators for further development and rooting. The highest percentage of regenerated shoots was obtained with 0.1 mg l-1 TDZ and 0.1 mg l-1 NAA after 4 weeks. Elongation and rooting was readily achieved when multiple shoots more than 1 cm in length were singled out and cultured on the MS medium without growth regulators. The plantlets were successfully adapted and grew vigorously in greenhouse conditions. This is the first report of shoot regeneration in the genus Cistus. The regeneration protocol developed in this study provides a basis for further investigation of the medicinally active constituents of this elite medicinal plant.

Expression of SOD transgene in pepper confer stress tolerance and improve shoot regeneration / Expresión del transgén SOD en el pimiento que confiere tolerancia al estrés y mejora la regeneración de brotes

The objective of this work was to study the stress tolerance and regeneration capability of transgenic pepper plants carrying a sod gene, encoding a tomato chloroplast-localized Cu/Zn SOD protein. The expression of the sod gene was confirmed by enzymatic staining following polyacrylamide gel electrophoresis (PAGE), revealing a ‘novel’ band, which could represent a heterodimeric enzyme. Transgenic T1 and T2 progeny plants were exposed to different oxidative stresses including Methyl viologen (MV) and drought and found to have an increased resistance to oxidative damage. Furthermore, the SOD carrying transgenic pepper plants showed increased levels of regeneration efficiency compared to the wild type pepper plants. Pepper is a recalcitrant species in terms of its in vitro regeneration ability but it could be extremely useful for the development of pharmaceuticals. This approach enables the extent use of pepper for genetic transformation and the production of high valuable products in plants particularly the large fruit varieties.