The influence of explants type and orientation on growth and development of Mandevilla sanderi (Hemsl.) Woodson in vitro

Abstract

Mandevilla sanderi is an important commercial ornamental pot plant. Traditional vegetative propagation is limited due to the low rate, therefore there is a need to develop an alternative, more efficient method. There is an interest in development of micropropagation technology for the species, as it allows to obtain a lot of offsprings in a relatively short time. The aim of the present work was to estimate an influence of explants type and position on regeneration of Mandevilla sanderi in tissue culture. Four different types of explants (leafy shoot tips, decapitated leafy shoot tips, defoliated shoot tips, decapitated and defoliated shoot tips) were used in the experiment, which were placed on the media vertically, while defoliated shoot tips were placed horizontally or vertically upside down. The explants were cultivated on a Murashige and Skoog (MS) medium supplemented with 1 mg·dm–3 benzyladenine (BA) and 0.5 mg·dm–3 indole-3-butyric acid (IBA). It was noted that both explants orientation and positioning, influenced the multiplication rate. Defoliated shoot tips placed horizontally were characterized by higher multiplication rate (6.8) in comparison to upside down vertical positioning (3.2). It was also observed that removal of shoot apex improved axillary branching, while defoliation of shoots placed in a normal position reduced multiplication rate.

Keywords

• regeneration
• multiplication rate
• explant defoliation
• explant decapitation