eChapter Name: Synthetic Seed Production Technology in Ornamental Plants
9789389130812
eBook Name: BREEDING AND BIOTECHNOLOGY OF FLOWERS: SET OF 2 VOLS. (SET PRICE)
by Anil K. Singh, Dr. A.K. Singh
INTRODUCTION
The seed (or zygotic seed) is the vehicle that connects one generation to another in much of the plant kingdom. By means of seed, plants are able to transmit their genetic constitution in generations and therefore seeds are the most appropriate means of propagation, storage and dispersal. A synthetic seed or ‘synseed’ is “an encapsulated single somatic embryo”, i.e., a clonal product that can be handled and used as real seed for transport, storage and sowing and that, therefore, would eventually grow either in vitro or ex vitro, into a plantlet through a process of “conversion”. Now a day, artificial seed technology is one of the most important tools to breeders and scientists of plant tissue culture.
In general, synthetic seeds are defined as artificially encapsulated somatic embryos, shoot tips, axillary buds or any other meristematic tissue, used for sowing as a seeds and posses the ability to convert into whole plant under in vitro and in vivo conditions and keep its potential also after storage (Capuano et al., 1998). The aim and scope for switching towards artificial seed technology was for the fact that the cost-effective mass propagation of elite plant genotypes will be promoted. There would also be a channel for new transgenic plants produced through biotechnological techniques to be transferred directly to the greenhouse or field. The artificial seed technology has been applied to a number of plant species belonging to angiosperms.
Artificial seeds have great potential for large scale production of plants at low cost as an alternative to true seeds (Roy and Mandal, 2008). An artificial seed is often described as a novel analogue to true seed consisting of a somatic embryo surrounded by an artificial coat which is atmost equivalent to an immature zygotic embryo, possibly at post-heart stage or early cotyledonary stage. The artificial seed production technique was first used in clonal propagation to cultivate somatic embryos placed into an artificial endosperm and constrained by an artificial seed coat. Today artificial seeds represent capsules with a gel envelope, which contain not only somatic embryos but also axillary and apical buds or stem and root segments (Vdovitchenko et al., 2011). Explants such as shoot tips, axillary buds and somatic embryos are encapsulated in cryoprotectant material like hydrogel, alginate gel, ethylene glycol, dimethylsulfoxide (DMSO) and others that can be developed into a plant. The coating protects the explants from mechanical damage during handling and allows germination and conversion to occur without inducing undesirable variations. They behave like true seeds and sprout into seedlings under suitable conditions.