Effect of plant growth regulators on in vitro plant regeneration of sandalwood (Santalum album L.) via organogenesis

Abstract

Santalum album L. is an economically important tropical tree species. Sandalwood trees are the source of highly priced and fragrant heartwood, the ‘East Indian Sandalwood’ that on steam distillation yields on an average 5–7 % oil of high perfumery value. Owing to extensive logging, changes in land-use patterns and poor natural regeneration, the natural sandal populations are rapidly dwindling. An efficient protocol of plant regeneration from node explant has been developed for S. album. Optimal callus was developed from nodal segments on woody plant medium (WPM) supplemented with 0.6 mg 1−1 TDZ and 1.5 mg 1−1 2,4-D. Fresh weight (132.3 mg) and dry weight (41.0 mg) of node derived callus were highest in medium supplemented with 0.6 mg l−1 TDZ. Shoot bud initiation was achieved from the surface of callus when transferred on shoot induction medium supplemented with BA and NAA in combination. Highest number of shoot buds (16.0) per callus was observed in medium containing 2.5 mg l−1BA + 0.4 mg 1−1 NAA. Shoot proliferation (number of shoots/callus) (21.5) and shoot length (4.7) was highest in media containing 3.0 mg 1−1 Kn. Plantlets were rooted on WPM medium with different concentrations of indole-3-butyric acid (IBA). Highest rooting percentage (82.37) and survival was achieved on WPM media with 1.5 mg 1−1 IBA. The in vitro raised plantlets with properly developed shoot and roots were acclimatized successfully and grew well in the greenhouse. All the regenerated plants appeared normal with respect to morphology and growth characteristics.