Conservation, Regeneration and Genetic Stability of Regenerants from Alginate-Encapsulated Shoot Explants of Gardenia jasminoides Ellis

Abstract

The present study demonstrates the potential of the alginate encapsulation of shoot tips and nodal segments of Gardenia jasminoides Ellis, the short-term cold storage of artificial seeds and subsequent successful conversion to desirable, uniform and genetically stable plantlets. Shoot tips and first-node segments below them, derived from shoots of in vitro cultures, responded better than second-to-fourth-node segments on agar-solidified Murashige and Skoog (MS) nutrient medium and thus, they were used as explants for alginate encapsulation. Explant encapsulation in 2.5% sodium alginate in combination with 50 mM of calcium chloride resulted in the production of soft beads, while hardening in 100 mM of calcium chloride formed firm beads of uniform globular shape, suitable for handling. The addition of liquid MS nutrient medium in the sodium alginate solution doubled the subsequent germination response of the beads. The maintenance of alginate beads under light favored their germination response compared to maintenance in darkness. Encapsulated shoot tip explants of gardenia, which were stored at 4 °C for 4, 8 or 12 weeks, showed a gradual decline in their regeneration response (73.3, 68.9, 53.3%, respectively), whereas, non-encapsulated explants (naked), stored under the same time durations of cold conditions, exhibited a sharp decline in regeneration response up to entirely zeroing (48.9, 11.1, 0.0%, respectively). Shoots, derived from 12-week cold-stored encapsulated explants, were easily rooted in solid MS nutrient medium with the addition of 0.5 μM of Indole-3-acetic acid (IAA) and after transplantation of the rooted plantlets individually to pots containing a peat–perlite (3:1, v/v) substrate, they were successfully acclimatized in the greenhouse under the gradual reduction of 75 or 50% shading with survival rates of 95–100%. The genetic stability of the acclimatized plantlets was assessed and compared with the mother plant using inter simple sequence repeat (ISSR) markers. ISSR analysis confirmed that all regenerated plantlets were genetically identical to the mother plant. This procedure of artificial seed production could be useful for the short-term storage of germplasm and the production of genetically identical and stable plants as an alternative method of micropropagation in Gardenia jasminoides.

Genetic Characterization of Gardenia jasminoides Ellis Genotypes Derived from Seeds and Selection Based on Their Morphological Traits and Flower Aromatic Substances

“…So far, sufficient research has been conducted to illustrate the genetic diversity of G. jasminoides Ellis using various molecular markers, such as ISSR (Inter-Simple Sequence Repeat), SSR (Simple Sequence Repeat), AFLP (Amplified Fragment-Length Polymorphism) and RAPD (Random Amplified Polymorphic DNA) [3,[8][9][10][11][12]. An ISSR analysis was used to evaluate the genetic relationship of G. jasminoides 'Radicans' and 'Grandiflora' [8].…”

“…An ISSR analysis was used to evaluate the genetic relationship of G. jasminoides 'Radicans' and 'Grandiflora' [8]. In addition, ISSR and AFLP molecular markers were employed to assess the genetic stability of gardenia plants produced from artificial seeds and micropropagation, respectively [9,10]. RAPD markers were used to detect genetic diversity in plants of G. jasminoides 'Pelion' grown as pot plants in Greece [3].…”

Dormancy breaking, indirect somatic embryogenesis, and encapsulation of somatic embryos in Black Zira

“…During arti cial seeds production with sodium alginate, for the hardening process, somatic embryos are mixed with the calcium chloride solution (50 to 300 mM). Hatzilazarou et al (2021) stated that explant coating in 2.5% sodium alginate in combination with 100 mM of CaCl 2 .2H 2 O led to the production of rm beads of uniform globular shape, proper for handling, while hardening in 50 mM of calcium chloride formed soft beads. Also, adding MS culture medium to sodium alginate increases the subsequent germination rate of beads.…”

Vegetative Propagation and ISSR-Based Genetic Identification of Genotypes of Ilex aquifolium ‘Agrifoglio Commune’

“…Moreover, they are ideal for species with limited genetic information, as in the case of I. aquifolium, as no special primers need to be constructed [16,17]. In addition, ISSRs are simple, easy to handle, widely available, reliable and highly effective [18][19][20][21][22].…”