Year: 2004
Type: article
Abstract: Summary Nodal sections of Quillaja saponaria cv. Quillay, including the proximal part of leaf laminae from 2-year old trees, as well as polynodal sections (3-4 axillary buds), were cultivated in Murashige and Skoog (MS) medium in the presence of various cytokinins, viz. benzyladenine (BA; 0.1, 0.5, 2.0 and 5.0 mg/litre), thidiazuron (TDZ; 0.1 and 1.0 mg/litre), 2,4-D (0.1 mg/litre), and NAA (0.1 and 0.5 mg/litre). High levels of BA and TDZ initiated profuse branching of the axillary bud and the induction of many new shoots and also callus formation in both explant types. From a single polynodal explant, >200 new multiple shoots developed in a period of 3-4 months. Proliferation of new shoots occurred mostly under the preexisting axillary bud(s) of the section and at the proximal end of the petiole with its intact leaf attached. Shoot clusters or isolated shoots elongated in subculture in the presence of MS medium without growth regulators or formed roots when supplemented with IBA within a period of 30-60 days, leading to plantlets. Root formation occurred in 1/2 strength MS medium with added 1% sucrose and 0.6, 1.2 and 5.0 mg IBA/litre, as single growth regulator. Roots did not form in lower IBA levels (0.1 mg/litre) while the addition of phloroglucinol or thiamine did not enhance rhizogenesis besides the IBA. Despite the strong shoot initiation occurring in both nodal and polynodal explants, morphogenesis was not observed in leaf explant sections, and callus derived from nodal sections, formed green globular structures only without further differentiation.
Authors: M. Jordan, C. Roveraro
Institution: Pontificia Universidad Católica de Chile
Language: English
Subfield: Plant Science
Domain: Life Sciences
Open Access status: hybrid
OpenAlex ID: W2560572987