Transverse thin cell layer (tTCL) technology: a promising tool for micropropagation of Centratherum punctatum Cass.

Abstract

Centratherum punctatum Cass. is an important medicinal herb used for various purposes. The present study describes an e cient protocol for the micropropagation of C. punctatum through transverse Thin Cell Layers (tTCLs). The effect of plant growth regulators (PGRs), thickness of tTCLs and source of tTCLs, were evaluated. The tTCLs of varying thickness (0.5-5.0 mm) were excised from 10-day-old leaf, 45-day-old node and internode and cultured on MS medium supplemented with various concentrations of PGRs (BAP, TDZ, KN; 0.1-2.0 mg/l) alone or in combination with NAA (0.1-1.0 mg/l) for shoot induction.For callus induction 2, 4-D (0.5-2.0 mg/l) was employed. The leaf and node tTCLs showed direct shoot regeneration and internodal tTCLs resulted in calli which successfully regenerated to shoots on subculture. A signi cant effect of thickness/width on shoot induction was observed. For leaf, 1.0 mm width and for node and internode 2.0 mm thick tTCLs showed maximum response. MS medium supplemented with 1.5 mg/l TDZ, 0.5 mg/l TDZ and 1.0 mg/l BAP in combination with 0.2 mg/l NAA were found optimum for shoot induction from tTCLs of leaf (96% response with 41.5 shoots per explant), internode (64% response with 22.9 shoots per explant) and node (87% response with 11.9 shoots per explant) respectively. Rhizogenesis was obtained when micropropagated shoots were transferred to half strength MS medium supplemented with various concentrations (0.25-2.0 mg/l) of IBA. The rooted plantlets were eventually acclimatized and transferred to soil. The procedure described here is a promising tool for micropropagation of C. punctatum as it produces high frequency healthy shoots from minimum explant source. Key MessageA rapid and e cient micropropagation protocol has been standardized in C. punctatum through transverse thin cell layer (tTCL) explants from leaf, node and internode.

In Vitro Propagation and Phytochemical Composition of Centratherum punctatum Cass—A Medicinal Plant

“…In C. punctatum, a medicinal ornamental plant, a 14-day-old in vitro-derived leaf was noted to be responsive in 0.5 mg/L Thidiazuronsupplemented media for direct and indirect shoot regeneration [14]. The same research group earlier described a C. punctatum micropropagation protocol through transverse thin cell layers technology (tTCLs) in which 1.0 mm wide leaves and 2.0 mm thick nodal explants were observed to be effective [15]. However, biotechnological methods involving other explants or regeneration mode and/or in vitro morphogenesis using PGRs was still not found to be sufficient.…”