From several decades, in vitro culture techniques are being used as a suitable method for germplasm conservation. The development of micropropagation protocols for rare, endangered, threatened or endemic plant species is sometimes difficult due to the lack of previous in vitro studies. Besides the establishment of in vitro culture of this kind of species, to obtain good multiplication and rooting rates and true-to-type acclimatized plants are main objectives to be achieved with the micropropagation protocols. Problems with the choice of the type and/or concentration of growth regulators are common in this kind of studies, resulting in callus formation and/or hyperhydricity. According to our experience, the double-phase culture system is a method that can improve growth and/or multiplication rate of in vitro-cultured plants. Since the preparation of the double-phase culture media is easy and the evaluation of the results obtained is fast, experiments to test its effects in the growth and development of in vitro-cultured plants could be of interest to achieve the aim of conservation.
Double phase; In vitro culture; Conservation; Micropropagation