ABSTRACT
Forest trees in general and those belonging to family Fabaceae in particular, have proved to be
recalcitrant for propagation through tissue culture. Saraca asoca (Roxb.) Willd. (Family-Caesalpinaceae)
is one such tree which has become vulnerable in nature due to over exploitation of its
bark. Four nutrient media [MS (Murashige and Skoog Medium), WPM (Woody Plant Medium), B5
(Gamborg’s Medium) and NN (Nitsch and Nitsch Medium, 1969)] and five doses of BA (N6-Benzyladenine)
(0, 2.2, 4.4, 8.8 and 17.8 μM) and their all possible interactions were tested for shoot
induction and proliferation from nodal segments of 3-year-old plants. B5 medium supplemented
with 2.2 μM BA was screened out as the most suitable medium shoot induction, proliferation and
elongation of regenerated shoots. In order to enhance shoot number, the nitrogen source in B5
medium was modified and five strengths of KNO3 (0.25×, 0.5×, 1.0×, 1.25× and 1.5×) were tested.
The different strengths of KNO3 (Potassium nitrate) had statistically significant effect on number
of shoots and on 0.25× strength of KNO3, maximum number of shoots (1.92) were obtained. The
modified strengths of KNO3 did not significantly affect the elongation of shoots. Effect of 5 durations
(quick dip, transfer of shoots after 1 day, after 3 days, after 5 days and after 7 days) of pulse
treatment with 200 μM IBA (Indole-3-butyric acid) in 1/2 strength MS liquid medium was tested.
Thereafter, the shoots were transferred to semi-solid half strength MS medium supplemented
with 0.2 μM IBA and 3.96 μM phloroglucinol. Pulse treatment of 5 days duration resulted in 37.5% in vitro rooting of shoots. Plantlets were hardened in soilrite soaked with half strength MS medium
in culture room and later shifted to a soil mixture in shade house.