In vitro multiplication of madhunashini
with BAP, Kn, IAA and 2,4-D at 0.5, 1.0, 1.5 and 2.0
and b). Cytokinins were found efficient for seed
mg l -1 , BAP + Kn and IAA + 2,4 – D at 1+1 mg l -1 . p H
germination than auxins (Figure 2a and b). It may be
of the medium was maintained at 5.8. Cultures were
due to; cytokinin is a well known hormone for cell
incubated at 25°C under white fluorescent light with
division, emergence of plantlets and their growth.
16:8 hours photoperiod. Cultures were observed
Whereas, auxin is known to promote callus formation
daily, and observation were recorded at regular
by keeping cells in unorganized condition. Nikolic
fortnightly intervals.
et al. (2006) while working on Lotus corniculatus
found that the germination percentage was highest
Sub culturing of leaf and nodal explants
in cytokinin rich media.
Leaf and nodal explants from the germinated
Height of plantlet was maximum in MS media
seedlings were subcultured to MS media
with BAP (0.5 mg l -1 ) and it is on par with other
supplemented with different concentrations of
concentrations of BAP and Kn (Table 1). It is evident
cytokinin media (BAP and Kn at 0.5, 1.0 and 2.0 mg
from this experiment that cytokinins help in cell
l -1 ). Cultures were observed daily and observation
division and shoot formation. Number of leaves was
was recorded at regular fortnightly intervals.
produced in the MS media containing cytokinins
Rooting
than auxins. This may be due to; cytokinin helps
in increasing intermodal length and leaf growth, as
Proliferated shoots were sub cultured for rooting
cytokinin promotes cell expansion in leaves (Taiz
into the MS media supplemented with IBA 1.0 mg
and Zeiger, 2003). In stevia also BAP was found to be
l -1 . Observations were recorded at weekly intervals.
best in producing multiple shoots, shoot length and
number of leaves (Pallavi et al., 2012).
Results and Discussion
Response of leaf and nodal explants in different
Effect of growth regulator supplemented media on
concentrations of cytokinin
culture of immature seeds
Number of shoots produced and shoot length were
Cent per cent of the explants responded when
maximum in the MS media supplemented with BAP
inoculated on MS media containing BAP (1.0 mg l -1 ),
than Kn. BAP was found superior than Kn (Table
Kn (0.5 mg l -1 , 1.0 mg l -1 and 2.0 mg l -1 ) and BAP +
2). Similar results were obtained by Joshi and Dhar
Kn (1.0+1.0 mg l -1 ) compared to control (Figure 1a
Table 2. Subculturing of leaf and nodal explants of madhunashini in different concentrations of cytokinins
Number of days taken
Number of
Shoot length
Number of
Response of
Growth regulators (mg l -1 )
for bud break
shoots
(mm)
leaves
leaf explants
BAP 0.5
7.00
2.80ab
17.51ab
2.12
0
BAP 1.0
7.75
5.50a
7.44c
3.10
0
BAP 2.0
7.60
2.60b
9.43bc
2.45
0
Kn 0.5
7.60
2.00b
18.53a
2.66
0
Kn 1.0
8.80
1.00b
7.63c
3.33
0
Kn 2.0
7.75
1.25b
11.94abc
2.50
0
F – test
NS
*
*
NS
CD @ 5%
-
2.86
8.65
-
SEm±
0.35
0.87
2.96
0.58
* Significant
NS – Non significant
893