In vitro induction and regeneration of callus from three inflorescence organs of Chinese narcissus (Narcissus tazetta L. var. chinensis Roem.)

Abstract

SummaryCallus induction and regeneration from ovary, pedicel, and scape explants of Chinese narcissus (Narcissus tazetta L. var. chinensis Roem.) ‘Jin Zhan Yin Tai’ were investigated. Two types of callus, compact and friable, were obtained, but only compact callus could differentiate into shoots. Initially, compact callus was produced on 1.0× Murashige and Skoog (MS) basal medium supplemented with both 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine (BA). The highest induction efficiency for all three types of explant was achieved from bulbs at development Stage III, when the inflorescences had 1.5 – 2.5 cm-long scapes. Callus from scape explants had a higher regeneration efficiency (73.1%) than calli from the other two types of explant when cultured on 1.0× MS medium containing 4.4 µM BA and 0.5 µM -naphthaleneacetic acid (NAA). Subsequent experiments in which scape explants were incubated directly on 1.0× MS medium containing 22.0 µM BA and 1.5 µM NAA in the light resulted in a high percentage of organogenesis from calli, with a shoot differentiation rate of 94.0% and an average of 5.84 shoots per explant. After small bulblets had formed, they were transferred to 1.0 MS medium supplemented with 2.5 µM NAA on which all shoots rooted and all bulblets later adapted well to soil conditions.These results provide a potential method for in vitro regeneration following genetic transformation of Chinese narcissus.