Influence of putrescine on anthocyanin production in callus cultures of Daucus carota mediated through calcium ATPase

The influence of Putrescine (Put) on the growth and elicitation
of anthocyanin in callus cultures of Daucus carota var. Nantes
scarlet was investigated through the use of ct-DL-difluoromethylarginine
(DFMA), the polyamine (PA) biosynthetic inhibitor.
It was observed that the addition of Put (0.05 mM) resulted
in enhancement of growth and anthocyanin content. The anthocyanin
content was found to be enhanced by 1.68 fold on the
21 st day as compared to the untreated controls. The PA inhibitor
was found to result in lowering of the growth and the
anthocyanin accumulation, which could be partially restored
by the addition of Put in combination with this inhibitor. The
levels of Ca2+ATPase were also found to be elevated in treatment
with Put suggesting the involvement of calcium in the
elicitation of anthocyanin. The endogenous titres of PAs and
the ethylene production under these treatments were also studied.
The treatment with DFMA resulted in lower levels of endogenous
PAs and higher levels of ethylene. Lowering of ethylene
by putrescine treatment shows that PA treatment also inhibited
ethylene formation, which would also imply that endogenous
ethylene does not influence anthocyanin production
in carrot callus cultures.