Current status and conservation of Pistacia germplasm.

The genetic erosion of Pistacia germplasm has been highlighted in many reports. In order to emphasize this and to focus more attention on this subject, national and international (especially IPGRI and IFAR) institutions have initiated projects proposing to characterize, collect and conserve Pistacia germplasm. Therefore, this paper reviews recent research concerning conventional (in situ and ex situ) and unconventional biotechnological conservation strategies applied to the preservation of Pistacia germplasm. As regards conventional conservation, the majority of germplasm collections of Pistacia species are preserved on farms (in situ) and in seed and field genebanks (ex situ), as well as in the wild, where they are vulnerable to unexpected weather conditions and/or diseases. Hence, complementary successful unconventional in vitro methods (organogenesis, somatic embryogenesis and micrografting) and slow-growth storage conditions for medium-term preservation of Pistacia are presented together with the morphological and molecular studies carried out for the characterization of its species in this review. Moreover, special attention is additionally focused on cryopreservation (dehydration- and vitrification-based one-step freezing techniques) for the long-term preservation of Pistacia species. Possible basic principles concerning the establishment of a cryobank for the successful conservation of Pistacia germplasm are also discussed.

Effects of different concentrations of benzylaminopurine on shoot regeneration and hypericin content in Hypericum triquetrifolium Turra.

The current study was undertaken to determine the effects of different benzylaminopurine (BAP) concentrations on the accumulation of bioactive hypericin in Hypericum triquetrifolium Turra. via micropropagation. To achieve this objective, seeds of H. triquetrifolium Turra. were cultured on Murashige and Skoog (MS) medium supplemented with a BAP (0.5, 1.0 and 2.0), 3% sucrose and 5.5% agar. Apical tips of axenic germinated seeds were proliferated on a MS medium supplemented with BAP (0.0, 0.5, 1.0 and 2.0 mg L(-1)). The highest shoot number was obtained from a MS medium supplemented with a 2.0 mg L(-1) BAP. Hypericin percentages were found to be highest in a 1.0 mg L(-1) BAP supplemented medium. These results provide the indication that cytokinin BAP can change the chemical composition of H. triquetrifolium Turra.; thereby, seriously impacting the quality and the efficacy of natural plant products produced by an in vitro culture system for aseptic production of hypericin.