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The somatic embryogenesis response is close linked with the development phase of the explant donor plant. Therefore, the objective of this work was to determine the effect of male flower position in the plant on the embryogenic responses in plantain cv. 'FHIA-21' (Musa AAAB). In this study male flower were collected at 0, 10, 20 and 30 cm from the last female flower. After 20 weeks on culture, the number of callus with somatic structures was evaluated. Thereafter, the effect of the callus morphology in the establishment of embryogenic cell suspensions was assessed. The results showed that the development phase of immature male flower (measured by the distance to the last female flower) was an important factor on the embryogenic callus induction. The best response on embryogenic callus formation (8.77%) was obtained with explants collected just after the last female flower (0 cm). Although, it was possible to assess that 85.0% of the callus composed by pro-embryogenic masses and somatic embryos in the early stage of its ontogeny development, resulted in embryogenic cell suspensions with the major volume of settled cell aggregated. As a result, it was possible to conclude that the age of the male flower play an important role on the somatic embryogenic process in plantain cv. 'FHIA-21'. [ABSTRACT FROM AUTHOR]

Comparison of two methods for the establishment of embryogenic cell suspensions obtained from the culture of male flower directly in liquid culture medium and embryogenic callus of banana cv. 'Grande naine' (Musa AAA) was studied in this work. Establishment of homogeneous embriogenic cell suspensions from the culture of both explants in liquid medium was achieved though floral bud range eight showed the best results. Differences in the growing of cell suspension, somatic embryos formation and germination was not observed when the suspensions were compared. Nevertheless the methodology proposed in this work was faster than the 'callus' methodology and percentage of establishment was higher. [ABSTRACT FROM AUTHOR]

Plant regeneration protocols are a requirement to develop plants transformation systems.The capacity of Phaseolus acutifolius A. Gray to regenerate plants from embryogenic callus formation was investigated. Two explants were used to form calli on a culture medium containing thidiazuron and indole-3-acetic acid. The embryonic axes showed better capacity than cotyledons to form embryos. Solar light was the most favourable to develop the in vitro plants. The 32% of somatic embryos with complete germination was achieved. These results indicate that somatic embryos formation and their germination in Phaseolus acutifolius A. Gray depended on the explant, culture medium and illumination conditions. In vitro-germinated plantlets were established in the greenhouse. [ABSTRACT FROM AUTHOR]

The adjustment of an efficient protocol of somatic embryogenesis in Stevia rebaudiana Bertoni to support programs of genetic breeding by genetic transformation is necessary. Few results are registered up to the moment in this species. The objective of this work was to obtain calli with embryogenic structures from clones of Stevia in vitro plants. Different variables were studied for the formation of calli: explants type, incubation conditions and genotype influences. Culture medium MS with different growth regulators (2,4-D; 6-BAP; TDZ) was used. These were used alone or in combination. Calli were multiplied in the best culture media. Afterwards they were subcultured to culture medium containing 2,4-D or TDZ with 40 and 60 g·l-1 of sucrose to induce proembryogenic mass formation. Calli formation was achieved after 45 days of culture in darkness and in culture media with 2.26 μM 2,4-D and 2.22 μM 6-BAP or 1.13 μM 2,4-D and 0.45 μM of TDZ. Foliar explants of in vitro plants of Stevia were used. Multiplication was achieved in the same culture media for calli formation. The largest amount of calli with development of proembryogenic mass was obtained when subcultures to culture medium with 0.45 μM 2,4-D adding 40 g·l-1 of sucrose was carried out after 45-50 days of culture. [ABSTRACT FROM AUTHOR]

The in vitro propagation of Dendrocalamus strictus (Rosb.) Nees is necessary. This type of plant is very important for the manufacture of furniture, construction of fences and buildings, for the paper industry, manufacturing of agricultural and musical instruments, elaboration of drugs, to provide their leaves as fodder for livestock, and reforestation. The development of protocols for regeneration via organogenesis and somatic embryogenesis is an efficient alternative to propagate this species. Cuba conditions are suited for this purpose. The effect of different concentrations of 2,4-D (2,4-dichlorophenoxyacetic acid) (1.0, 2.0, 4.0 mg·l-1) and kinetin (0.5, 1.0 mg·l-1) was determined in order to form calluses in vitro from seeds of D. strictus. Results showed that in vitro callus formation from seeds of Dendrocalamus strictus (Rosb.) Nees treatment was achieved using 2,4-D and kinetin at a concentration of 1.0 mg·l-1. [ABSTRACT FROM AUTHOR]

The somatic embryogenesis propagation technique and tool for the genetic improvement in sugar cane (Saccharum spp. hybrid) has presented multiple inconveniences that the regeneration protocols described in the literature have not been able to solve. The present research was carried out with the objective of developing a new methodology for the establishment of cell suspensions of sugar cane, var. C 87-51, through somatic embryogenesis based on segments of the sheath of the leaves of in vitro plants, placed directly in a liquid culture medium. The results demonstrated that it is possible to form callus with embryogenic structures based on segment two of the sheath of the leaves which reduces the time of culture in vitro and guarantees the physiologic and phytosanitary quality of the plants that are regenerated. Homogeneous lines of cellular suspensions formed by embryogenic aggregates were established based on callus with embryogenic structures. [ABSTRACT FROM AUTHOR]