In-vitro propagation of bixa orellana - a natural dye producing tree

Abstract

Direct somatic embryogenesis and plant regeneration was achieved from excised immature zygotic embryos of Bixa orellana - a ornamental and natural dye producing tree. The zygotic embryos were cultured initially on half-strength MS (Murashige and Skoog’s, 1962) medium supplemented with 0.1 mgl-1 of Kn. Though, germination of immature zygotic embryos and plants regeneration was achieved in all the three media compositions tested. However, in one medium containing Kn (0.1 mgl-1), about 10 per cent direct somatic embryos were produced on the hypocotyl portions. After culturing for 30 days, high frequency of somatic embryogenesis and maturation of somatic embryos was obtained in the same medium. These somatic embryos could be germinated into plantlets by giving 2-3 sub-cultures at monthly intervals onto half-strength MS medium supplemented with 0.1 mgl-1 of Kn. The regenerated plants having 2-3 cm long shoots and 2-3 pairs of leaves with roots were hardened in polybags containing soil mixture and subsequently established in field.