In vitro selection and regeneration of zinc tolerant calli from Setaria italica L.

Abstract

Zinc tolerance in Setaria italica L. in vitro was achieved through callus culture derived from leaf base and mesocotyl explants on Murashige and Skoog's medium supplemented with 0.5 mg/l kinetin and 3.0 mg/l 2,4-D + 0.24 mM zinc. Tolerant calli showed vigorous growth in medium containing 0.24 mM zinc than the non-tolerant calli. Biochemical studies on the basis of activities of peroxidase and catalase as well as estimation of protein and chlorophyll were more in tolerant calli than non-tolerant one. The accumulation of zinc in the callus was increased significantly with the increase in zinc concentrations in the medium. Plant regeneration via somatic embryogenesis was achieved in both tolerant and non-tolerant calli on MS medium containing 1.0 mg/l BA, 1.0 mg/l Kn and 0.5 mg/l 2,4-D. The somatic embryo-derived plantlets were tested in - MS liquid medium with 0.24 mM zinc for selection of tolerant clone. This study may help in the selection and characterization of metal tolerant lines of Setaria italica for breeding programmes.