ABSTRACT
Transformed hairy root cultures of Valeriana officinalis were
established by infection with Agrobacterium rhizogenes strain
ATCC 15834. To determine the effect of different media on
the growth of V. officinalis hairy roots, MS, B5 media (1.0X
and 0.5X strength), N6 medium and a modified MS medium
without phytohormones were used. In addition, different NH4
+
to NO3
-
ratios in MS medium were studied. The effects of
these treatments were evaluated after 21 days of culture in
relation to hairy root growth. B5 and ½ B5 media were the best
basal media for hairy root growth. MS medium supplemented
with a 20:20 ratio (mM) of NH4
+
to NO3
-
displayed highest
growth rates and biomass yield in hairy root cultures. The
present study demonstrated that the composition of culture
medium and the ratio of different nitrogen sources have
significant impact on the growth of V. officinalis hairy roots.
Key words: Valeriana officinalis, hairy root, medium