Abstract:
Withania somnifera (L.) Dunal (Sin: Amukkara, San: Ashwaganda) is a valuable
medicinal plant, belongs to the family Solanaceae. W somnifera is normally propagated
by seeds but wall of the fruit contains a chemical which prevent seed germination.
n 21 {:(':...i,:; ::' .)·'I~) ·~~;I·.'~ .;__ ~l .):_1,. (~. ~\ .. ' ..or,. (.~. '\"
. 1 " J \.' ::;,-- ...
.J <: " .:. The objective of this study was to develop successful protocol to
acclimatize in vitro propagated plants of Withania somnifera and compare tissue cultured
plants with seed raised plants based on growth, physiology, anatomy and chemically.
In the present study nodal segments, shoot tips and leaf pieces were used as explants in
different growth regulator combinations (auxines and cytokinines). All tested explants
produced calli and best callus production was observed in MS medium supplemented
with 1.0 uM Kin, 4.5 uM BAP and 1.5 uM NAA under 14 days dark period. Shoot
initiation was observed in the same medium from the calli produced from shoot tips and
nodal segments. Highest shoot multiplication was observed in MS medium supplemented
with 9.0 uM BAP and 1.0 ulvl IAA. Callus produced from leaf pieces did not respond in
any medium to produce shoots. No significant difference was observed among tested
treatments for rooting, suggesting growth regulator free MS medium was the best
medium for rooting of W somnifera. In vitro produced plants were acclimatized
successfully in a potting mixture of river sand: top soil: compost in 2: 1: I ratio. Rate of
photosynthesis was higher in tissue cultured plants at three months and six months
compared to seed raised plants. TLC finger prints and densitometry was used to compare
chemical identities (steroids considered) and it was found that there is no significant
difference in chemical identities present in tissue cultured and seed raised plants.
