Putrescine influences growth and production of coumarins in hairy root cultures of witloof chicory (Cichorium intybus L-cv. Luckuow local)

The effect of putrescine (Put) on the growth and production of two coumarin s, esculin and esculetin, in hairy roots of chicory (Cichorium intybus L. c v. Lucknow local) was examined. To study the role of Put on growth and prod uction of coumarins, polyamine inhibitors, namely alpha-DL-difluromethylorn ithine and alpha-DL-difluromethylarginine were used at 1 mM concentration. Put treatment at 1.5 mM produced a 1.9-fold increase in the growth of hairy roots, as well as the production of esculin and esculetin. The treatments with polyamine (PA) inhibitors resulted in much lower growth and production of coumarins compared with both 1.5-mM Put treatment and the control. Both free and conjugated PAs were studied over the whole culture period, and co njugates of all three PAs, namely Put, spermidine, and spermine, were highe r than free PAs throughout the culture period. The treatments with PA inhib itors showed lower levels of endogenous PAs compared with Put-treated sampl es. The treatment with 1.5 mM Put showed maximum accumulation of endogenous conjugated Put (2,098 +/- 157 nmoles gm(-1) fresh weight). The production of esculin and esculetin was strictly correlated with growth in all treatme nts. Put at 1.5 mM resulted in greater length of primary root (18.3 +/- 1.4 cm) as compared with the control (11 +/- 0.9 cm) and larger numbers of sec ondary and tertiary roots.