Influence of Polyamines on Growth of Hairy Root Cultures of Witloof Chicory (Cichorium intybus L. cv. Lucknow Local) and Formation of Coumarins

The effect of polyamines (putrescine, spermidine,
and spermine) was examined for growth and production
of two coumarins, esculetin and esculin, in the
hairy roots of chicory (Cichorium intybus L. cv. Lucknow
local). Of the polyamines administered, 1.5 mM putrescine
alone resulted in a 2.3-fold higher increase in the
growth of hairy roots as well as in the production of
esculetin and esculin, which was 3.37 times more than
that of the control on day 21. The endogenous level of
conjugated putrescine was more than fivefold that of free
putrescine levels in untreated samples. The production of
esculetin and esculin in hairy root cultures strictly correlated with growth in all of the treatments. Putrescine at 1.5 mM resulted in a greater length of primary root (18.29 ± 1.37 cm) compared with the control (10.96 ± 0.82 cm) and more secondary and tertiary roots. This study also provides insight into the morphogenetic changes that occur in roots in response to the external supply of polyamines.