Effect of Chitosan on In Vitro Growth and Development of Dendrobium formosum Roxb.

Abstract

Dendrobium formosum seedlings were cultured on solid and liquid VW (Vacin and Went, 1949) media supplemented with commercial chitosan or chitosan from cuttlebone at various concentrations (5, 10, 20, 40 and 60 ppm). The cultures were incubated at 252 ^oC under cool white-fluorescent light at 2000 lux for 16 hours and maintained for 3 months. The results showed that VW solid medium supplemented with 5, 20, 40 and 60 ppm of commercial chitosan or 10 ppm of chitosan from cuttlebone could enhance growth on a fresh weight basis compared to the control without chitosan. Chitosan from cuttlebone at concentrations of 5-40 ppm promoted the number of roots. The shoot length, number of leaves and number of shoots of the seedling treated with commercial chitosan were not significantly different from those treated with chitosan from cuttlebone. Culture in liquid medium supplemented with low concentration of chitosan enhanced seedling growth.