In Vitro Micro-propagation of Cordyline and Dieffenbachia Plants

This study was carried out in Plant Tissue Culture Laboratory of the Faculty of Environmental Agricultural
Sciences, El-Arish, North Sinai, Suez Canal University, Egypt during the period from April 2013 to March 2015. The
objective of this study was to optimize the micro-propagation protocol for Cordyline terminals and Diffenbachia picta
cv. "Tropica" in order to make the in vitro propagation feasible and economical by enhancing the slow rate of
multiplication of traditional methods. Results indicated that BA at 1.0 mg/l-1 combined with 0.1 mg/l-¹ NAA surpassed
all other cytokinins (Kin and 2ip) with significant increase on number of axillary shoots/explant, axillary shoot length,
number of leaves/shoot. During establishment stage, Main shoot length (2.55, 3.90 cm, 7.33 and 7.04 cm, respectively)
on cordyline and (2.33, 4.19 cm, 9.40 and 6.33 cm, respectively) on dieffenbachia. However, in multiplication stage,
data revealed that increasing BA concentrations significantly increased growth of cordyline and dieffenbachia compared
with control. Data showed that addition of 2 mg/l-1 BA combined with NAA at 0.1 mg/l-1 recorded the highest values of
number of axillary shoots/explant, axillary shoot length, number of leaves/shoot and main shoot length (2.86, 5.55 cm,
9.40 and 8.77 cm, respectively) on cordyline, while values were 2.66, 5.66 cm, 9.88 and 8.66 cm, respectively on
dieffenbachia. The combination between licorice extract and sucrose significantly increased growth parameters of
cordyline. The highest values of number of axillary shoots/explant, axillary shoot length, number of leaves/shoot and
main shoot length (2.30, 3.25, 6.15 and 4.20, respectively) were recorded with on cordyline belongs MS medium + 30
g/l-1 sucrose and licorice at 40 mg/l-1, combined with (BA) at 2 mg/l-1 and 0.1 mg/l-¹ NAA. On the other side, number of
axillary shoots/explant of dieffenbachia was not affected by the medium supplementation with the mentioned factors.
For rooting stage, results revealed that NAA was the best auxin in roots induction of cordyline and dieffenbachia with
high significant increase in root length and number of roots. While, there was no difference among NAA, IBA and IAA
in rooting percentage. Moreover, NAA at 1.0 mgl-1 recorded the highest values of number of roots and root length
(10.00 and 21.33 cm, respectively) on cordalyine and (8.00 and 8.53 cm, respectively) on dieffenbachia. Rooted
plantlets were ex vitro acclimatized (95% survival) of cordyline and dieffenbachia when they were cultured in (1:1:1:1,
v/v/v/v) peat moss, perlite, vermiculite and sand before transferred to soil.