Morphogenic potentialities of flower buds of Kalanchoe pinnata Pers. grown in vitro

Abstract

Excised flower buds of Kalanchoe pinnata Pers. representing two early stages of development (designated sets I and II), were cultured on modified White's medium (WB). They failed to attain full development on WB or on WB containing any of the following supplements: indole-3yl-acetic acid (IAA), 2,4-dichlorophenoxyacetic acid (2,4-D), naphthaleneacetic acid (NAA), kinetin, or coconut milk (CM). A slight stimulation of the growth of corolla was caused by kinetin (10 ppm). IAA (I ppm) and NAA (I ppm) induced rooting from the cut end of the pedicel and from the proliferated torus tissue situated between the sepals and petals. 2,4-D (I ppm) either singly or in concert with CM (10 per cent) stimulated the formation of shoot buds and root growth. Addition of kinetin (I and 10 ppm) to WB favoured shoot formation, but suppressed rooting. Flower buds of set II developed shoot buds more readily than those of set I. Thus, the primordia floral organs present in the immature buds lose their ability for normal morphogenesis under culture conditions. Buds destined to form flowers can be made to revert to vegetative growth.