In vitro regeneration of silktree (Albizzia julibrissin) from excised roots

Abstract

Root segments (1 cm long) were excised from 15-20 day old seedlings of silktree (Albizziajulibrissin) grown on B5 medium. About 50% of the control (no growth regulators added) root explants formed shoot buds within 15 days after placement on the culture medium. After 30 days, there were about 4 shoots per control explant. Addition of low levels of various auxins (0.5 #M) did not influence the formation of shoot buds from the explants. Higher concentrations (5 #M), however, decreased shoot regeneration. Kinetin and 2iP did not influence shoot regeneration at the concentrations tested (1 & 10 #M). Addition of benzyladenine, Zeatin, or thidiazuron to the culture medium increased both the percentage of explants that formed shoots and the number of shoots per explant. Thidiazuron was highly effective in stimulating shoot formation at low concentrations (<1 #M). At 0.05 #M thidiazuron, 95% of the explants produced shoots and about 10 shoots were formed per explant. Compared to TDZ, higher concentrations (10 #M) of benzyladenine and Zeatin were required to enhance shoot formation. Upon excision and transfer to B5 medium, regenerated shoots developed into normal rooted plantlets.

In vitro differentiation and plant regeneration of Albizia chinesis (Osb.) Merr

“…However, shoot differentiation and growth was poor in TDZcontaining media. This observation also corroborated previous reports on the effective role of TDZ in producing shoot formation in many woody trees, with an inhibitory effect on growth and elongation at higher concentrations (Thomas and Katterman, 1986;Huetteman and Preece, 1993;Sankhla et al, 1994Sankhla et al, , 1996. On the other hand, a high concentration of BAP (4.0 mg l 21 ) was found to be superior in producing multiple shoots of varying sizes per explant culture (Table 1).…”

Histological analysis of somatic embryogenesis and adventitious shoot formation from root explants of Centaurium erythreae Gillib

“…Although extensive research has been carried out on in vitro organogenesis and embryogenesis in cultivated Centaurium species (Barešová 1988), there is little information on the development of somatic embryos and shoots or their cellular origin. Certain herbaceous plant species have been reported to be capable of forming somatic embryos (Twyford et al 1996, Tylicki et al 2000 and adventitious buds (Sankhala et al 1996) from root explants. The aim of present work is to evaluate the histological aspects associated with the induction and development of somatic embryos and adventitious shoots from root explants of Centaurium erythreae Gillib.…”

Genetic fidelity assessment of in vitro-regenerated plants of Albizia julibrissin using SCoT and IRAP fingerprinting

“…Roots excised from 15-to 20-d-old in vitro A. julibrissin seedlings and cultured on B5 medium with the ethylene precursors/generators 1-amino-cyclopropane-1-carboxylic acid and 2-chloroethylphosphonic acid formed callus, but subsequent shoot formation was inhibited (Sankhla et al 1995). Excised root segments from 15-to 20-d-old in vitro silk tree seedlings cultured on B5 medium containing NAA, indole-3-acetic acid (IAA), IBA, kinetin, BA, 6-(γ,γ-dimethylallylamino)purine (2iP), zeatin, or TDZ formed some callus after 1 wk in culture (Sankhla et al 1996). As in our study, a combination of an auxin with a cytokinin has been widely used for successful induction of organogenic callus in many commercially or medicinally important regeneration systems.…”

“…There is, however, limited information available on in vitro plant regeneration for this species. A. julibrissin can be regenerated via adventitious shoot morphogenesis from cotyledons, hypocotyls, and roots (Sankhla et al 1993(Sankhla et al , 1994(Sankhla et al , 1995(Sankhla et al , 1996Zhou et al 2001) or through somatic embryogenesis (Burns and Wetzstein 1998).…”