In Vitro Shoot-Tip Culture Of Petunia Hybrida
Abstract
Petunia hybrida has increasingly been a highly-demanding ornamental plant and a
promising model for micropropagation. The goal of this study was to enhance the
effectiveness of the micropropagation of shoot-tip Petunia plants with the optimum
treatments. The source of explants was initially prepared in vitro on one-third Murashige
and Skoog (MS) basal medium. According to the result of this study, the procedure of
sterilisation was recorded with the optimum treatment when the seeds were sterilised with
sodium hypochlorite (NaOCl) followed by 1.6% for a duration of 5 minutes. The survival
and germination percent of seeds were 100%. For the shoot multiplication experiment, the
shoot-tip was taken from in vitro explants and transferred to various media. The effects of
different levels of macro ingredients in MS basal medium without plant growth regulators
influenced the development of shoot-tip explants. MS with one-third macro ingredients
resulted in the most regeneration of shoot-tip. One-third MS was then chosen to combine
with various levels of BA (0.01 mgL-1
, 0.05 mgL-1
, 0.1 mgL-1
). It was reported that the
addition of 6-benzyladenine (BA) inhibits the growth of shoot-tip compared to media
without BA. The highest shoot tips were recorded in media with BA (0.01 mgL-1
).
However, multi-shoot clusters were formed in other treatments associated with BA
ranging from 0.05 to 0.1 mgL-1
. Finally, these shoots were then rooted with the supplement
of auxin indole-3-acetic acid (IAA) (0.05 mgL-1
, 0.1 mgL-1
, 0.2 mgL-1
) on one-third MS
media. The highest average number of roots (35.87 roots/ explant) and longest roots were
cultured on the rooting hormone-free medium. Nevertheless, it was observed that the roots
associated with IAA treatments grew thicker in size and elongated more consistently in
length than untreated roots. Overall, 1.6% NaOCl in 5 minutes was the most effective
treatment for sterilising seeds. One-third MS had a better effect on the shoot-tip culture of
Petunia. BA ranged from 0.05-0.1 mgL-1
induced more shoot formation. IAA induced
shorter roots and less root number than hormone-free treatment.