Propagation and Bulblet Enhancement of Rhodophiala pratensis from Seeds Germinated In Vitro

Abstract

Rhodophiala pratensis is an endemic geophyte from Chile with great importance to the national market of cut flowers and potted and garden plants. However, many geophytes have conservation issues and are considered endangered species. Efficient and controlled propagation techniques have been useful for the commercial production of this species and for its conservation. A micropropagation protocol using seeds was developed to determine an optimum method to increase bulb production rates and plant production. The effect of sucrose levels in the medium on the growth of bulbs was tested in vitro (30, 60 and 90 g L -1 ). Then, the effects on shoot and bulb induction of the cytokinin BAP at concentrations of 1.0, 2.0 and 4.0 mg L -1 with the auxin NAA at concentrations of 0.1, 1.0 and 2.0 mg L -1 were analyzed. The germination rate after eight weeks increased to 86% with very low contamination (7%). Bulb growth increased when high levels of sucrose were added to the medium; the optimum sucrose concentration was 90 g L -1 . Acclimatization was successful, with a plant survival rate of 63% and an average bulb growth of 0.5 cm. This is the first study to demonstrate the possibility of propagating R. pratensis seeds in vitro.