IN-VITRO PROPAGATION OF WESTERN-AUSTRALIAN RUSHES (RESTIONACEAE AND RELATED FAMILIES) BY EMBRYO CULTURE .1. IN-VITRO EMBRYO GROWTH

This study outlines the first method for initiating micropropagation o f a wide range of wild and commercially significant species of various Southern Hemisphere rushes (Restionaceae) by embryo culture. Most spe cies showed best embryo growth on half-strength Murashige and Skoog ba sal medium, with the addition of gibberellic acid (1-5 mu M) and/or ze atin (1-5 mu M). Results showed there was a high level of variability in seed germinability as indicated by in vitro embryo growth (6-96%), with no apparent link to growth form, generic status or habitat prefer ence. Embryo growth was achieved for several rare and/or restricted ta xa (Loxocarya 'magna' ined Lepidobolus contorta Meney & Dixon Hopkinsi a anoectocolea (F Muell.) Cutler, Lepidobolus contorta Meney & Dixon i ned). The low germination of whole seeds of most species (average of 1 0%) indicates that whole seed germination under controlled conditions considerably understates the potential germinability of species of Res tionaceae. In this context, embryo culture is useful for assessment of germinability and for initiating stock cultures for micropropagation.