Intergeneric hybridization among colchicaceous ornamentals, Gloriosa spp., Littonia modesta and Sandersonia aurantiaca via ovule culture

Abstract

Abstract Colchicaceous plants, Gloriosa spp., Littonia modesta and Sandersonia aurantiaca, are cultivated as ornamentals. However, unfortunately no large variations in horticultural traits are found within each genus. We examined intergeneric hybridization using 6 genotypes of Gloriosa spp., 1 genotype of L. modesta and 2 genotypes of S. aurantiaca to obtain wider variability and to develop novel cultivars in those groups. Following intergeneric cross-pollination, putative hybrid plantlets were obtained via ovule culture in various combinations. Early confirmation of the hybridity of ovule culture-derived plantlets was accomplished by flow cytometry and random amplified polymorphic DNA analyses. Several intergeneric hybrids have so far been produced flowers and subjected to morphological characterization. All the hybrids examined, i.e. L. modesta×S. aurantiaca, L. modesta×S. aurantiaca 'Phoenix', L. modesta×G. superba 'Lutea', L. modesta×G. 'Marron Gold', S. aurantiaca×G. superba 'Lutea', S. aurantiaca×G. 'Marron Gold' and S. aurantiaca 'Phoenix'×G. 'Marron Gold', had novel morphological characteristics compared with their parents, some of which were horticulturally attractive. The results obtained in our series of studies indicate the validity of intergeneric hybridization in the improvement programs of colchicaceous ornamentals. We are now examining to develop a rapid and efficient micropropagation system and to restore fertility by artificial chromosome doubling of intergeneric hybrids that had been produced in our series of experiments. © 2009 The Japanese Society for Plant Cell and Molecular Biology.