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Somatic Embryogenesis in Cocos nucifera L.

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Somatic Embryogenesis: Fundamental Aspects and Applications

Abstract

In our coconut laboratory micropropagation has been the subject of research for nearly three decades, as this plant species is highly recalcitrant for in vitro regeneration and so far only achieved through somatic embryogenesis as the sole path for coconut regeneration. Of all the explants tested, plumules have proved to be the most responsive and the process efficiency has been improved by indirect embryogenesis and thereafter secondary embryogenesis and callus multiplication, this strategy is currently applied in floral explants. Two different approaches have been used to find ways to have a more efficient protocol. The first one, a direct and practical method, included plant hormones and activated charcoal. On the other hand, the indirect approach consisted in basic studies on: morphohistological development, biochemical and physiological aspects such as uptake of exogenous auxin, levels of endogenous auxin; shoot apical meristem formation and maintenance (KNOX gene family); the occurrence and expression of genes related to the cell cycle control (Cyclin-Dependent Kinase), and somatic embryogenesis (Somatic Embryogenesis-Related Kinase); and the establishment of a transformation protocol. A better understanding of the somatic embryogenesis of coconut was achieved by these approaches. This way, in the short term there is no doubt that we will have mass propagation options based not only in plumule explants but also on rachillae, unfertilized ovary, and leaf explants.

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Acknowledgments

The authors would like to thank V. Hocher and J-L. Verdeil IRD/CIRAD Montpellier, France, respectively, where the isolation of CnCDKA and CnKNOX were carried out and M. Strnad for the analysis of cytokinin content (Institute Experimental Botany, Czech Republic). Partial funding of the research reported here was from CONACyT, México (Grant no. 43834-Z) and a scholarship was awarded to T. Pérez-Nuñez (No. 162930), M. Montero-Cortés (No. 183253), A. Azpeitia (No. 119335), A. Andrade-Torres (No. 204774). G. Rivera-Solís (No. 242979). G. Sandoval-Cancino (No. 300614).

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  1. Unidad de Biotecnología, Centro de Investigación Científica de Yucatán, Calle 43 No. 130, Colonia Chuburná de Hidalgo, CP 97200, Mérida, Yucatán, Mexico

    Luis Sáenz-Carbonell, Mayra Montero-Cortés, Teresa Pérez-Nuñez, Alfonso Azpeitia-Morales, Antonio Andrade-Torres, Iván Córdova-Lara, José Luis Chan-Rodríguez, Gabriela Sandoval-Cancino, Gustavo Rivera-Solis & Carlos Oropeza-Salín

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  1. Luis Sáenz-Carbonell
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  2. Mayra Montero-Cortés
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Correspondence to Carlos Oropeza-Salín .

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  1. Unidad de Bioquímica y Biología Molecular de Plantas, Centro de Investigación Científica de Yucatán, Mérida, Yucatán, Mexico

    Víctor M Loyola-Vargas

  2. Departamento de Ingeniería Genética de Plantas, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Mexico

    Neftalí Ochoa-Alejo

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Sáenz-Carbonell, L. et al. (2016). Somatic Embryogenesis in Cocos nucifera L.. In: Loyola-Vargas, V., Ochoa-Alejo, N. (eds) Somatic Embryogenesis: Fundamental Aspects and Applications. Springer, Cham. https://doi.org/10.1007/978-3-319-33705-0_18

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