Micropropagation of Salix pseudolasiogyne from nodal explants

Abstract

The effect of phytohormones on the breaking of dormancy of axillary buds in Salix pseudolasiogyne and their subsequent proliferation from nodal explants were examined. Nodal explants obtained from a 20-year-old S. pseudolasiogyne tree were cultured either on woody plant basal medium (WPM) or WPM supplemented with benzyladenine (BA, 2.2/4.4 lM), zeatin (1.1/2.2 lM), gibberillic acid (GA 3 , 2.9 and 14.5 lM), and GA 3 + BA (2.9 + 4.4 lM). Although axillary shoots developed in all the media, a higher percentage bud break occurred on BA supplemented media. To corroborate the results, endogenous levels of cytokinins [Cks, N 6 -isopentenyladenine (iP), zeatin riboside (t-ZR), dihydrozeatinriboside (DHZR)] and abscisic acid (ABA) were determined. On BA supplemented media, the levels of zeatin type (Z-type) of Cks were higher than those of isopentenyladenine type of Ck in the explants, while the ABA level was low. Axillary shoots did not grow well and became necrotic upon subculture to fresh basal WPM. In order to improve shoot growth, they were subcultured twice at a 4-week interval on to WPM supplemented with BA (2.2/4.4 lM), GA 3 (1.4 lM), or GA 3 + BA (1.4 + 4.4/2.9 + 4.4 lM). Maximal shoot growth (93%) was achieved on WPM supplemented with 2.2 lM BA. Comparative analyses of endogenous Cks revealed that higher Cks (Z-type Cks) were present in actively growing shoots. Rooting was readily achieved when the shoots were subcultured to WPM without phytohormones. The rooted plants were acclimatized well upon transplantation.

Propagação in vitro de Erythrina velutina

“…No entanto, o maior percentual de brotos enraizados (75%) ocorreu no meio de cultura WPM acrescido de 2,46μM de AIB. Resultados semelhantes ao encontrado no presente trabalho foram reportados por PARK et al (2008), que observaram enraizamento de brotos de Salix pseudolasiogyne em meio de cultura WPM, na ausência de reguladores de crescimento. Em Arbus unedo L., os brotos também foram capazes de enraizar em todas as condições testadas, até mesmo na ausência de auxinas; entretanto, altas frequências de indução de raízes (entre 76,7 e 93,3%) foram alcançadas com a adição de 25,0μM de AIB no meio de enraizamento por seis dias (GOMES & CANHOTO, 2009).…”

Rapid in vitro propagation system through shoot tip cultures of Vitex trifolia L.–an important multipurpose plant of the Pacific traditional Medicine

“…Generally, a cytokinin is required for shoot induction and proliferation. However its effective type and optimal concentration varies with the system (Park et al 2008). A differential response with regard to shoot bud induction was observed when shoot tip explants were cultured on a medium supplemented with different concentrations of BA, Kin and 2-iP (0.0-10 μM) as listed in (Table 1).…”

Biotechnological methods of in vitro propagation in willows (Salix spp.)

“…Micropropagation efforts have been successful with Salix genera in the past [13,14,18,[35][36][37]. We used four of these species (genotypes) in our experiments: S. alba, S. hastata, S. matsudana and S. lapponum.…”