This study demonstrates a rapid, economic and efficient plantlet
regeneration protocol for an exotic ornamental and medicinal plant Allamanda cathartica L. by using shoot tip explants. Interaction of various PGRs (mT, IAA, IBA
or NAA) and sucrose was tested in MS medium to obtain maximum shoot regeneration
from shoot tip explants. mT (3.0 µM) + NAA (0.5 µM) + 4% sucrose was found to be
an optimum combination for maximum shoot proliferation with 20.80 mean shoot
number and 7.60 cm mean shoot length after 12 weeks of culture based on 93.20%
responsive explants. Microshoots (4-5 cm) showed maximum rhizogenic response as
they produced 4.20 mean root number with 4.90 cm root length after 4 weeks of culture
on ½ MS medium when supplemented with 0.5 µM NAA. Well-developed rooted
plantlets were acclimatized successfully with a 96% survival rate. The primary
phytochemical screening of aqueous leaf extract in the regenerants revealed the
presence of proteins, carbohydrates, lipids, phenols, proteins, and saponins.
Quantification of phytochemical constituents showed that the amount of phenols was
highest, followed by lipids, proteins, carbohydrates, saponins and alkaloids in the
micropropagated plants. These phyto-constituents are known to cure numerous
ailments.
Keywords: Acclimatization, In vitro rooting, Micropropagation, PGRs, Sucrose.
