In vitro propagation of Kaempferia galanga (L)

Abstract

Kaempferia galanga (L) is an aromatic perennial herb, which is widely used in Ayurvedic medicine.Dry tubers are imported in large scaie to Sri Lanka due to lack of mass production in Sri Lanka.Disease susceptibility and higher cost of production have restricted its cultivation. Propagation ofKaempferia galanga is normally by rh izorne cuttings but disease susceptibi Iity of tender rh izomesrestricts propagation in large scale. Propagation through other vegetative methods is not possible.Rahman et al. (2004) reported the possibility of obtaining plants through somatic embryogenesis butthe survival rate was low. Therefore an attempt was made to develop a protocol for mass propagationof Kaempferia galanga through direct organogenesis.

Leaf discs and axi Ilary buds were used as explants. Axi Ilary buds isolated from rh izomes of Kaempferiagalanga mother plants were sprayed with 0.2% Captan ™ 2-3 days before collection. After that, theywere placed on a wet paper Iined tray and covered again with another wet paper. Five to six dayslater young axillary buds were emerged from nodes and they were used as explants. For leaf discexplants leaves were washed with soap and soaked in a solution of Teepol" for 15 minutes, andwashed with running tap water for 45 minutes.

Both leaf discs and axillury buds were dipped in 5% Chlorox ™ (5.25% Sodium hyperclorite v/v) for10-15 minutes under sterile conditions. Then they were washed 10% Clorox r for 3 minutes and 70%ethanol for one minute each followed by two successive washings in sterile distilled water. Explantswere cultured on MS basal medium (Murashige and Skoog, 1962) supplemented with differentconcentrations of Benzyl amino purine (BAP) and Indole acetic acid (IAA) (2.00 mgl' - 2.25 rngl'and 0.30 mgl-I- 0.70 mgi' respectively). Sucrose 3% (w/v) and 0.8% agar were added to the media.pH was adjusted to 5.8.

Cultures were incubated under 16 hr light 18 hr dark at 26 :.+:: I DCtemperature for 21 days. Callusingwas not observed from both tested explants in any of the media tested. After 15 -18 days of incubationaxillary buds were elongated in all combinations tested. MS supplemented with 2.25 rngl' BAP and0.5 rngl' IAA showed the highest elongation (490 ± 10 mrn).

After 25-30 days of incubation in vitro grown shoots were cut and separated from the explant. Thenthey were subcultured on the same medium and incubated in 16 hr light at 26 ± 1 DCtemperature forshoot multiplication. MS medium was used as basal medium with above combinations of growthregulators.

The highest multiplication was observed in 2.25 mgl:' BAP and 0.5 mg' IAA (7.0 ±..0.02) shoots perexplant. Further sub culturing on to the same medium induced roots. Seven-weeks old plantlets wereremoved from culture vessels, washed well to remove all agar and transferred to small plastic potscontaining sand, soil and compost in I: I: 1 proportion by volume and kept in shade house covered withpolythene bags, for acclimatization. 100% survival was observed when acclimatized plants weretransferred to the field.