effect of 6-benzyl-aminopurine and thidiazuron on in vitro shoot organogenesis of aloe vera (l.) burm. f

Abstract

Aloe (Aloe vera [L.] Burm. f.) is an important medicinal herb and is propagated vegetatively. However, its propagation rate is slow and cannot supply good quality planting material to large-scale growers. It is therefore necessary to use in vitro clonal propagation for commercial purposes. The aim of this study was to select a suitable medium for initial culture establishment and subsequent shoot multiplication of aloe. Shoot tips were excised from aloe plants and disinfected with 20% Clorox (5.25% sodium hypochlorite) for 30 min. Sterilized shoot tips were vertically dissected into quarters and then inoculated on Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurine (BAP) or thidiazuron (TDZ) (1, 2, and 3 mg L-1) combined with 0.5 mg L-1 1-naphthaleneacetic acid (NAA). Results revealed that there was a significant difference (P < 0.05) between different hormone combinations in shoot bud formation. Explants placed in 3 mg L-1 BAP and 0.5 mg L-1 NAA produced significantly (P < 0.05) higher numbers of microshoots than other tested treatments. The medium containing a low concentration of TDZ (1 mg L-1) with NAA produced multiple microshoots, whereas the highest TDZ concentration (3 mg L-1) with NAA produced high levels of abnormalities. Transferring microshoot buds from 1 mg L-1 TDZ to 3 mg L-1 BAP accelerated production of prominent and elongated shoots. The MS medium supplemented with 3 mg L-1 BAP and 0.5 mg L-1 NAA produced higher number of normal shoots per explant of aloe under in vitro conditions.