In Vitro Micropropagation Of Ornamental Rare Species Sibirarea Altaiensis: An Endemic Of Altai

Sibiraea altaiensis (Laxm.) Schneid. is an endemic plant species of Altai, having great ornamental importance. In this study, efficient protocol for in vitro micropropagation of this rare plant was developed for the first time. Lateral buds with part of stem, excised from 1-2 years old shoots of mature trees of S. altaiensis were used as explants. Explants after sterilization were cultured on modified Murashige and Skoog's (mMS) medium, in which concentration of nitrate and ammonia nitrogen was reduced by 4 times and concentration of vitamins was increased. Concentration of agar in the medium was 0.35% (w/v). The shoot bud proliferation was the best on mMS medium supplemented with 6-benzylaminopurine (6-BAP) at 1.0 mg L-1 after 3 weeks of culture. Further, subculture on mMS medium without use of plant growth regulators (PGRs) for 3 weeks stimulated regeneration of 2-3 axillary shoots at explants. The shoot multiplication (5.83 +/- 0.2) was the best on mMS medium supplemented with 1.0 mg L-1 6-BAP after 3 weeks of culture. A large number of multiple shoots (28 shoots/explant) was observed by the tenth subculture on multiplication medium (alternation of 5 subcultures with 1.0 mg L-1 6-BAP for 3 weeks and 5 subcultures without PGRs for 3 weeks). Shoots were best rooted in vitro on mMS medium without PGRs within 4 weeks. The plantlets with roots were effectively acclimatized in growth substrate - peat: sand: vermiculite (1:1:1) within 2 months (83.3%) and in the open ground within 3 months (50.0%). This protocol can be used effectively for rapid propagation and conservation of S. altaiensis at commercial scale. (C) 2019 Friends Science Publishers