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This is the first study related to micropropagation and phytochemical analyses of Cleome dendroides, an endemic species of the Brazilian Atlantic Forest, a biome affected by human activity. Among the classes of substances produced by the genus Cleome, the glucosinolates are used as chemotaxonomic markers. They have a wide structural diversity, which affords, for example, antineoplastic bioactivity. The micropropagation was established using explants from two sources: seedlings and in vitro plants. The morphogenic response was evaluated on Murashige-Skoog (MS) medium with different concentrations of benzyladenine (BA). Hypocotyl explants from seedlings and stem explants from in vitro plants showed higher capacity of shoot regeneration (56.3-100%). Shoot proliferation (75-100%) was maintained when hypocotyl explant-derived shoots and stem explant-derived shoots were subcultured three times a month. Hypocotyl explant-derived shoots maintained on MS + 2.0 mgL-1 BA induced the highest shoot production along the subcultures. Shoots were elongated and rooted on growth regulator-free MS medium. Plantlet establishment was successful in the hardening medium composed of Plantmax® substrate, reaching 85%survival. The phytochemical studies indicated two glucosinolate derivatives, highlighting the presence of 5,6-dimethyltetrahydro-1,3-oxazine-2-thione, identified for the first time in plants. This work demonstrates an efficient method for in-vitro production of C. dendroides plants, which can be used as a source of glucosinolates. [ABSTRACT FROM AUTHOR]

This report highlights the first successful cryopreservation of in vitro shoot tips of Cleome rosea, achieved by the vitrification technique using aluminum cryo-plates (V cryo-plate). The effects on survival and recovery of C. rosea shoot tips of different plant vitrification solutions (PVS2 and PVS3), light intensity (standard and dim light), and 6-benzyladenine (BA) supplementation (0.10, 0.25, or 0.50 mg L for 1 or 3 wk) in the recovery medium were investigated. Cryopreserved shoot tips showed high regeneration frequencies when treated with PVS2 and PVS3, reaching survival frequencies of 97 and 70%, respectively. When placed onto medium without growth regulators, recovery of cryopreserved shoot tips did not exceed 33% (obtained with PVS2) or 23% (PVS3). Supplementation of recovery medium with 0.5 mg L BA for 3 wk increased both survival and recovery to 100% after cryopreservation following treatment with either PVS2 or PVS3. These values were maintained even when shoot tips were cultured in the presence of 0.10 mg L BA for 1 wk. Maintenance under dim light resulted in better phenotypic characteristics of plants produced from cryopreserved shoot tips. [ABSTRACT FROM AUTHOR]

Adventitious root cultures of Cleome rosea were established using root segments from proximal and middle root regions of in vitro-propagated plants. The root explants were cultured in liquid MS medium supplemented with the following growth regulators: naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), 2,4-dichlorophenoxyacetic acid (2,4-D), and N-furfuryladenine (KIN). The highest biomass accumulation was obtained with roots, cultured in media with NAA. The use of 2,4-D resulted in callus formation, while explants cultured in the presence of KIN developed buds. Protocols for long-term maintenance of in vitro roots through cryopreservation by vitrification were also evaluated using plant vitrification solution 2 (PVS2). The use of NAA during pre- and post-culture steps was essential to recovery after exposure to liquid nitrogen. On the other hand, the presence or absence of light during culture maintenance had little effect on the process. The highest recovery frequency after cooling in liquid nitrogen (63.6 ± 14.4%) was reached after exposure to PVS2 for 30 min. The cryopreserved roots showed excellent ability to multiply, which remained stable for up to five subcultures. Moreover, these roots also displayed the capacity for shoot induction when cultivated on solid MS medium supplemented with 0.50 mg/L 6-benzyladenine (BA), reaching regeneration frequencies of 60-82% over five subcultures. [ABSTRACT FROM AUTHOR]