The present study demonstrates an efficient protocol for alginate encapsulation, interim cold storing of artificial seeds and conversion to genetically stable plants of Viburnum dentatum L. “Lucidum Aiton”. Explants of shoot tips and first-node segments, excised from in vitro-derived viburnum microshoots, were encapsulated in 2.5% sodium alginate mixed with liquid MS nutrient medium and hardened in 50 mM of calcium chloride producing solid, soft and uniform beads. These artificial seeds achieved 28.9% germination under light, forming 4.3 microshoots per bead. However, with 100 mM of calcium chloride for hardening, the beads were firm and of a uniform globular shape and suitable for handling and exhibited a germination response of 48.9%. Encapsulated shoot tip explants of viburnum, which were stored at 4 °C for 4, 8 or 12 weeks, showed a gradual decline in regeneration response (73.3, 62.2, 51.1%, respectively), while non-encapsulated explants, stored under same conditions, did not survive after the fourth week of cold storage. Microshoots from cold-stored encapsulated explants, which were rooted in solid MS nutrient medium with 0.5 μΜ of Indole-3-acetic acid (IAA) and transplanted to a substrate of peat-perlite (3:1, v/v), acclimatized successfully after application of 75 or 50% shading, which was gradually reduced, and were established with minimum losses in a greenhouse. For the genetic stability of the artificial seed-derived plantlets and compared with the mother plant, an assessment was conducted using Inter Simple Sequence Repeats (ISSRs) analysis. The ISSR profiles proved the genetic uniformity and clonal stability of the regenerated plantlets and their genetic resemblance to the mother plant. The present regeneration procedure could be used as an alternative method for the micropropagation of V. dentatum.
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