Influence of polyamines on growth and formation of secondary metabolites in hairy root cultures of Beta vulgaris and Tagetespatula

Growth of hairy roots of Beta vulgaris, which produces betalaines,
and of Tagetes patula, which produces thiophenes, was
studied under the influence of externally treated polyamines.
Of the three polyamines, viz. putrescine, spermidine and spermine,
administered singly at 1.5 mM concentration, putrescine
and spermidine at 0.75 mM concentration influenced increase
in the accumulation of biomass of B. vulgaris and T. patula
hairy roots by 1.42 and 1.30 fold over the control. Whereas, the
treatment of spermine (1.5 mM) alone resulted in decrease in
the biomass in both the systems. Combined administration of
putrescine (0.75 mM) and spermidine (0.75 mM) enhanced
growth in both B. vulgaris and T. patula than that observed in
individual treatments. Polyamines administered alone or in
combination did alter production of betalaine and thiophene
content. Dose response experiments showed that, when putrescine
and spermidine was administered at 0.75 mM concentration,
it resulted in maximum biomass and production of betalaine
and thiophene in B. vulgaris and T. patula respectively as
compared to the control and the media treated with double and
triple strength of nitrates and in combination with putrescine
and spermidine at equimolar concentration. In B. wdgaris and
T. patula hairy root cultures, endogenous spermine titers were
maximum in putrescine and spermidine 0.75 mM each treated,
cultures, which was 1.63 and 2.0 fold higher than in control on
28 th and 35 th days respectively.