Seed cryopreservation of the native cacti Discocactus zehntneri, Pilosocereus gounellei and Stephanocereus luetzelburgii from Bahia, Brazil

The native cacti species from Bahia, Discocactus zehntneri, Pilosocereus gounellei and Stephanocereus luetzelburgii, as other members of the Family Cactaceae, have been dramatically affected by illegal traffic, and with the destruction and fragmentation of their habitats. Considering the potential extinction risks for endangered species, and the several applications of these species, some actions on ex situ conservation of cacti are required. Thus, this work aimed to evaluate the physiological quality of seeds from D. zehntneri, P. gounellei and S. luetzelburgii stored in liquid nitrogen (-196°C) for 0, 7 and 30 days. For this purpose, seeds of the three species were transferred to cryovials and then immersed directly in liquid nitrogen for 7 or 30 days. After the storage period, the seeds were removed from the nitrogen tank, and thawed for 1 h at ambient temperature and subsequently chemically sterilized. The seeds were inoculated onto Petri dishes lined with two layers of germitest paper. The germination rate of the three species was not reduced by exposure to liquid nitrogen, as well as D. zehntneri that had the best results for speed and germination rate observed in seeds stored for 30 days.Keywords: Cacti, cryoconservation, ex situ conservation, germinationAfrican Journal of Biotechnology Vol. 12(21), pp. 3250-325

Organogênese direta de Orthophytum mucugense Direct organogenesis of Orthophytum mucugense

Orthophytum mucugense é uma bromélia ornamental endêmica do município de Mucugê-BA que está passível de extinção. O objetivo deste trabalho foi estabelecer um protocolo de regeneração via organogênese direta para a espécie. Os explantes raiz, caule e folha, oriundos de plantas com diferentes idades, foram inoculados em meio de cultura MS½ suplementado com BAP e ANA. Os brotos foram inoculados em meio contendo AIB e carvão ativo. As plantas foram transferidas para substrato composto de vermiculita e terra. A maior taxa de brotação foi obtida com o explante caule com 20 e 40 dias de idade em meio com 0,65mM de ANA. Na fase de enraizamento, a presença de carvão ativo interferiu positivamente no comprimento da parte aérea e do sistema radicular das plantas. As plantas foram aclimatizadas com 100% de sobrevivência.<br>Orthophytum mucugense is an ornamental bromeliad endemic to the municipality of Mucugê-BA which is vulnerable to extinction. The aim of this study was to establish a regeneration protocol via direct organogenesis for the species. The explants root, stem and leaf from plants of different ages were inoculated in the MS½ culture medium supplemented with BAP and NAA. The shoots were inoculated on medium supplemented with IBA and activated charcoal. The plants were transferred to a substrate composed of vermiculite and soil. The highest rate of sprouting was obtained with stem explants of 20 and 40 days old in medium supplemented with 0.65mM of NAA. For rooting the presence of activated charcoal had a positive influence on the length of shoot and root plants system. The plants were acclimatized with 100% survival