In vitro regeneration of Hygrophila Schulli (buch. ham) M. R. & S.M. Almeida through callus mediated somatic embryogenesis

Hygrophila schulli, a tropical herb belonging to the family Acanthaceae, is an important medicinal plant, primarily used as diuretic, haematinic and liver tonic. Present work deals with the strategies for the in vitro propagation of the species. Well developed compact calli were obtained when cotyledonary leaf and cotyledonary node explants were cultured in MS medium with 0.2 mg/l 2,4-D together with 0.2 mg/l BA. Subculture of the callus in the regeneration medium of MS supplemented with BA (1-2 mg/l) singly or in combination with NAA (0.1 mg/l) induced large number of embryoids in the form of green tubercles all over their surfaces. 1mg/l BA used singly yielded the best result. Embryoids were initially studied under a stereobinocular microscope and their bipolar nature was subsequently confirmed through scanning electron micrography. Excised embryoids grown in basal medium developed into vigorous plantlets bearing healthy shoots and well ramified roots. Hardening and acclimatization of the regenerants were acomplished following standard methodologies.