In vitro Conservation of Rose Coloured Leadwort: Effect of Mannitol on Growth of Plantlets

Abstract

In vitro study of manitol on conserved rose coloured leadwort (Plumbago indica Linn.) was conducted. Nodal segments containing one axillary bud were cultured on Murashige and Skoog (MS) medium + 30 g/l sucrose. The results of different addition of mannitol (0, 20, 40 and 60 g/l) to the media with plant growth regulator (PGR) (0.5 mg/l BA + 0.16 mg/l IAA) or without PGR were compared. The nodal segments were in vitro conserved under 50 µmol m^-2s^-1 light intensity and 12 h photoperiod at 25^oC without subculture. It was found that mannitol added to the media could reduce the growth of plantlets derived from buds of nodal segments especially the height of plantlets was reduced up to 83.1% in media with PGR and 93.3 % in media without PGR. Mannitol at concentrations of 40 and 60 mg/l had tended to reduce the number of shoots per plantlet. The plantlets could survive on 20 g/l mannitol until eight months of conservation without any dead plantlet and the plantlets were still vigorous. The survival plantlets from every medium could regenerate new shoots after subculture onto the fresh medium.