In addition to IBA concentration, the period of
pulse treatment has been shown to have significant
effects on the average number of roots produced per
shoot on Catharanthus roseus (Rupesh et al. 2013).
Meera and Manjushri (2005) reported that when
treating Garcinia indica Chois shoots with IBA, the
longer the shoots were soaked in IBA, the greater the
chance, the shoots would have two roots. However,
in the present study, this did not occur. Commonly,
explants treated with higher concentrations of IBA
(containing auxin) and soaked for longer periods
did not grow multiple roots. They did exhibit
unconventional root growth, with roots forming
above the base rather than from the bottom of the
shoot base (Figure 5C,D).