RESUMO
This review work focuses on how the secondary chemistry could help in the survival of plants in high mountain habitats under extreme environmental conditions. The elevated levels of stress in high areas of the tropic and subtropic change dramatically not only by following the annual cycles of winter and summer but they also change in a single day. Some species, however, are able to successfully grow at heights more than 3000 m in the tropical mountains due, in part, to highly specialized physiological processes that affect their physical and chemical responses. In this study, it describes some strategies of how the secondary metabolites could help the plants to stand the high levels of stress in the high mountain ecosystems.
Este trabajo de revisioÌn se centra en coÌmo la quiÌmica secundaria podriÌa ayudar en la supervivencia de plantas en haÌbitats de alta montanÌa en condiciones ambientales extremas. Los altos niveles de estreÌs en las zonas altas del troÌpico y subtroÌpico cambian dramaÌticamente no solo al seguir los ciclos anuales de invierno y verano, sino que tambieÌn cambian en un solo diÌa. Sin embargo, algunas especies pueden crecer con eÌxito a alturas superiores a 3000 m en las montanÌas tropicales debido, en parte, a procesos fisioloÌgicos altamente especializados que afectan sus respuestas fiÌsicas y quiÌmicas. En esta revisioÌn, se describen algunas estrategias de coÌmo los metabolitos secundarios podriÌan ayudan a las plantas a soportar los altos niveles de estreÌs en los ecosistemas de alta montanÌa.
Assuntos
Plantas/química , Estresse Fisiológico , Óleos Voláteis/química , Altitude , Floroglucinol/análise , Floroglucinol/química , Terpenos/análise , Terpenos/química , Flavonoides/análise , Flavonoides/químicaRESUMO
ABSTRACT The preservation of banana genetic material is usually performed through seedlings. However, most banana cultivars do not produce seed and are propagated vegetatively. Therefore, cryopreservation is a feasible technique that allows the preservation of banana genotypes indefinitely. For the success of cryopreservation protocols, the selection of cryoprotectants and pre-freezing techniques are important factor. Therefore, the objective of this study was to verify the effects of different cryoprotectants with and without 1% phloroglucinol and pre-cooling periods on the development of a protocol for cryopreservation of in vitro rhizomes ofMusa accuminata(AAA) cv Grand Naine banana. The addition of 1% phloroglucinol to the cryoprotective solutions, such as PVS2 enhanced recovery of cryopreserved banana rhizomes. In addition, pre-cooling of explants in ice for 3 hours in PVS2 + 1% of phloroglucinol allowed efficient cryopreservation of banana rhizomes, followed by successful recovery and regeneration of in vitro shoots of banana cv Grand Naine.