The ornamental tropical heliconia plants are of great interest in Brazilian floriculture, and
among them stands out Heliconia chartacea (Barry x Lane) var. Sexy Pink, whose
micropropagation allows to obtain large-scale plants, with genotype identical to the common
ancestor and high health status. In order to determine the composition of the culture medium
and the effect of cytokinin Benzylaminopurine (BAP) and Tidiazuron (TDZ) for
multiplication in vitro, the effect of different concentrations of sucrose in the culture medium
for rooting in vitro and the influence of different substrates on the acclimatization of plants of
H. chartacea var. Sexy Pink., We tested different levels of nitrogen and calcium in the basic
culture medium MS (Murashige and Skoog, 1962) in combination with BAP, TDZ and BAP,
with or without coconut water. Treatment with MS medium plus 0.25 mg L-1 TDZ, followed
by MS treatments and 3 mg L-1 BAP and MS with 220.00 mg L-1 and 0.25 CaCL2.2H2O mg
L-1 TDZ presented the best answers to issue and size of the shoots, confirming Nannetti &
Pinto (1995), who reported a need for different concentrations of cytokinins for different
levels of nitrogen and calcium to the development of the sprouts Heliconia sp. It was also
found that for variations of concentrations of BAP no statistical differences between
treatments with 2 and 3 mg L-1 with or without coconut water, however, concentration 2 mg
L-1 and 10% water Coconut comferiu best results proving to be the best medium for the
multiplication of H. chartaceae var. Sexy Pink. For rooting, plantlets with 3 to 5 cm high were
inoculated in culture medium MS with half the salt concentration (MS/2) supplemented with
different concentrations of sucrose (0, 15, 30, 45 and 60 g L-1). The absence of an endogenous
source of sugar did not inhibit root formation, but these were few and very thin. When the
sucrose concentration used was 15 to 60 g L-1, production of root biomass was increased
giving the plant a greater chance of establishment for the acclimatization stage. Doses of 45
and 60 g L-1 decreased the dry mass of roots thus enabled the formation of roots thickened and
brittle due to greater accumulation of water in tissues. There were no significant differences in
the average number of roots per explant in different concentrations of sucrose the exception of
the control treatment, but comparing the dry weight of roots, one can ascertain that the
addition of sucrose at a concentration of 30 g L-1 in MS medium, showed the highest increase
in mass, proving to be the best medium for rooting of H. chartacea var. Sexy Pink. For
acclimatization, we used six types of substrate, T1: Bioplant® T2: Coconut fiber, T3: Coir +
Bioplant®, T4: Coir + Earthworm casting; T5: Coir + Bioplant® + Earthworm casting and T6:
sand, vermiculite. The survival rate ranged from 83% to 92% with no statistical differences
between treatments. The T3 gave a further development of the root system than others, and
the T1 and T6 substrates, those who had a less developed. There was a greater accumulation
of dry matter in shoots of plants acclimatized in T2, followed by its variations T3, T4 and T5,
favoring more vigorous seedlings. The substrate prepared with coconut fiber was what
provided the greatest increase in dry mass of shoot and root, the most suitable for
acclimatization of Heliconia chartacea (Barry Lane x) var. Sexy Pink.
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