Abstract

Advancements in plant cell tissue culture have helped to address the problems faced with several economically important plant species. Micropropagation and encapsulation technologies have been combined to make a new innovation called ‘artificial seeds’ or ‘synthetic seeds’ or “synseed” which combines both advantages of these two technologies. Alginate coats are used for artificial seeds to encapsulate somatic embryos/vegetative buds/ micro propagules that can act as seeds. They can then be germinated into plantlets upon incubation under in vitro or in vivo conditions and retain their regeneration potential after storage at low temperatures. Germplasm preservation and exchange between national and international laboratories may rely on using encapsulated propagules of elite plants. Also, this technology has been successfully exploited for cryopreservation by use of encapsulation - dehydration, or encapsulation - vitrification in germplasm storage of elite plant species. This review gives an overview of latest developments on synseed technology with special emphasis on explant selection for making successful synseeds as well as matrices that are used as an encapsulation material for synseeds. Moreover, the constraints impeding the advancement of seed technology and related future perspectives are also discussed.

• 1.   Ahmad N, Faisal M, Fatima N, Anis M. Encapsulation of microcuttings for propagation and short-term preservation in Ruta graveolens L.: a plant with high medicinal value. Acta Physiologiae Plantarum 2310-34:2303;2012.
• 2.   Antonietta GM, Emanuele P, Alvaro S. Effects of encapsulation on Citrus reticulata Blanco somatic embryo conversion. Plant Cell, Tissue and Organ Culture 1998;55:235–238.
• 3.   Ara H, Jaiswal U, Jaiswal VS. Synthetic seed: prospects and limitations. Curr Sci 2000;78:1438- 1444.
• 4.   Bapat VA, Mhatre M, Rao PS. Propagation of Morus indica L. (Mulberry) by encapsulated shoot buds. Plant Cell Rep 1987;6:393–395.
• 5.   Bapat VA, Mhatre M. Bioencapsulation of Somatic Embryos in Woody Plants. In Protocol for Somatic Embryogenesis in Woody Plants; Springer: Dordrecht, The Netherlands, 2005. pp 539–552.
• 6.   Chen RR, Zhang JT, Li BP, Guo SS, Hao JP, Zhou XM. Studies on the production of artificial seeds of Coriander. Chin J Biotechnol 1991;7:127-134.
• 7.   de Moraisi TP, Asmari SA, De Jesus Silva HF, Luz JM, de Melo B. 2018. Application of tissue culture techniques in potato. Biosci J Uberlândia 2018;34:952-969.
• 8.   Ganapathi TR, Srinivas L, Suprasanna P, Bapat VA. Regeneration of plants from alginate-encapsulated somatic embryos of banana cv. Rasthali (Musa SPP. AAB Group). In Vitro Cell Dev Biol Plant 2001;37:178–181.
• 9.   Gray DJ. Purohit A, Triglano RN. Somatic embryogenesis and development of synthetic seed technology. Crit Rev Plant Sci 1991;10:33–61.
• 10.   Hassanein AM, Ibrahiem IA, Galal AA, Salem JMM. Micropropagation factors essential for mass propagation of Banana. J Plant Biotechnol 2005;7:175-181.
• 11.   Hwang EK, Park CS, Baek JM. Artificial seed production and cultivation of the edible brown alga, Sargassum fulvellum (Turner) C. Agardh: Developing a new species for seaweed cultivation in Korea. J Appl Phycol 2006;18:251–257.
• 12.   Janeiro LV, Ballester A, Vieitez AM. In vitro response of encapsulated somatic embryos of camellia. Plant Cell, Tissue and Organ Culture 1997;51:119–125.
• 13.   Khor E, Ng WF, Loh CS. Two-coat systems for encapsulation of Spathoglottis plicata (Orchidaceae) seeds and protocorms. Biotechnol Bioeng 1998;59;5:635-639.
• 14.   Kitto SL, Janick J. Polyox as an artificial seed coat for sexual embryos. HortScience 1982;17:488.
• 15.   Kitto SL Janick J. Hardening Treatments Increase Survival of Synthetically Coated Asexual Embryos of Carrot. J Amer Soc Hortic Sci 1985;110:283-286.
• 16.   Lal N, Ahuja PS. Plantlet development from encapsulated shoot buds of Picrorhiza kurroa - An endangered medicinal plant. Physiol Mol Biol Plants 1995;1:191-193.
• 17.   Mariani TS, Sasmitamiharja D, Mienanti D, Latif S, Ginting G, Miyake H. Somatic Embryogenesis of Oil Palm (Elaeis guineensis Jacq.) for Synthetic Seed Production. Asian J Appl Sci 2014;2:358-367.
• 18.   Mathur J, Ahuja PS, Lal N, Mathur AK. Propagation of Valeriana wallichii DC using encapsulated apical and axial shoot buds. Plant Sci. 116–60:111;1989.
• 19.   Murashige T. Plant cell and organ cultures as horticultural practices. Acta Hortic 1977;78:17-30 (In Proceedings of the Symposium on Tissue Culture for Horticultural Purposes, Ghent, Belgium, 6–9 September 1977).
• 20.   Nandini B, Giridhar P. Insight View of Topical Trends on Synthetic Seeds of Rare and Endangered Plant Species and Its Future Prospects. In: Faisal M, Alatar A, Editors. Synthetic Seeds. Springer, Cham. 2019. pp 113-154.
• 21.   Piccioni E, Standardi A. Encapsulation of Micropropagated Buds of Six Woody Species. Plant Cell, Tissue and Organ Culture 1995;42:221-226.
• 22.   Radzuan NS, Hasbullah NA, Patah FK, Idris H, Lassim MM. Production of Artificial Seeds of Carica papaya L. var Eksotika. Journal of Science and Mathematics Letters 2019;7:66-71.
• 23.   Redenbaugh K, Fujii JA, Slade D. Encapsulated plant embryos. In: Mizrahi A, Editor. Advances in Biotechnological Processes, Alan R. Liss Inc.: New York, NY, USA, 1988. pp 225–248.
• 24.   Redenbaugh K, Fujii JA, Slade D. Hydrated coating for synthetic seeds. In: Redenbaugh K, Editor. Synseeds: Application of the Synthetic Seeds to Crop Improvement, CRC Press: Boca Raton, FL, USA, 1993. pp 305–327.
• 25.   Redenbaugh K, Paasch BD, Nichol JW, Kossler ME, Viss PR, Walker KA. Somatic seeds-encapsulation of asexual plant embryos. Nat Biotechnol 1986; 4:797–801.
• 26.   Redenbaugh K, Slade D, Viss P, Fujii JA. Encapsulation of somatic embryos in synthetic seed coats. HortScience 1987;22:803–809.
• 27.   Standardi A, Micheli M. Encapsulation of in vitroderived explants: An innovative tool for nurseries. Methods Mol Biol 2013;11013:397–418.
• 28.   Verleysen H, van Bockstaele E, Debergh P. An encapsulation-dehydration protocol for cryopreservation of the azalea cultivar ‘Nordlicht’ (Rhododendron simsii Planch.). Sci Hortic 2005;106:402–414.
• 29.   Redenbaugh K, Fujii J, Slade D, Viss P, Kossler M. Artificial Seeds - Encapsulated Somatic Embryos. In: Bajaj YPS, Editor. High-Tech and Micropropagation I. Biotechnology in Agriculture and Forestry, Vol 17. Springer, Berlin, Heidelberg, 1991. pp 395–416.
• 30.   Ruffoni B, Massabo F, Giovannini A. Artificial seed technology in ornamental plants, Lasianthus and Genista. Acta Hortic 1994;362:297-304.
• 31.   Sripathy KV, Groot SPC. Seed Development and Maturation. In: Dadlani M, Yadava DK, Editors. Seed Science and Technology. Springer, Singapore, 2023. pp. 17-38.
• 32.   Standardi A, Piccioni E. (1998) Recent Perspectives on the Synthetic Seed Technology Using NonEmbryogenic in Vitro-Derived Explants. Int J Plant Sci 1998;159:968-978.
• 33.   Sharma S, Shahzad A, Teixeira da Silva JA. Synseed technology - a complete synthesis. Biotechnol Adv 2013;31:186–207.
• 34.   Schultheis JR, Chee R, Cantliffe, DJ. Effect of growth regulators and gel carriers on growth and development of sweet potato (Ipomoea batatas) somatic embryos. Hort Sci 1986;21:210.
• 35.   Suprasanna P, Bharati G, Ganapathi TR, Bapat VA. In vitro development of encapsulated somatic embryos in rice, Trop Agric Res Extension 2002;5:76-78.
• 36.   Sandoval-Yugar EW, Vesco LLD, Steinmacher DA, Stolf EC, Guerra MP. Microshoots encapsulation and plant conversion of Musa sp. cv. ‘Grand Naine’. Cienc Rural 2009; 39:998–1004.
• 37.   Sundararaj SG, Agrawal A, Tyagi RK. Encapsulation for in vitro short-term storage and exchange of ginger (Zingiber officinale Rosc.) germplasm. Sci Hortic 2010;12:761-766.
• 38.   Vdovitchenko MY, Kuzovkina IN. Artificial Seed Preparation as the Efficient Method for Storage and Production of Healthy Cultured Roots of Medicinal Plants. Russian J Plant Physiol 2011;58:524.

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