HORTICULTURAL CHARACTERIZATION OF AN INTERGENERIC HYBRID BETWEEN A SEPTAPLOID GLORIOSA CULTIVAR AND SANDERSONIA AURANTIACA
Both Gloriosa spp. and Sandersonia aurantiaca are tuberous plants belonging to the family Colchicaceae. They have recently become popular worldwide as cut flowers or potted plants because of their beautiful, unique flowers and good vase life. Since no large variations in horticultural traits are found within each genus, we have examined intergeneric hybridization among colchicaceous ornamental plants in order to obtain wide variability in horticultural traits and to develop novel cultivars. To date, hybrid plants have been produced via ovule culture in various intergeneric cross-combinations. In the present study, horticultural characterization of an intergeneric hybrid of G. superba Verschild (Gve; 2n=7x=77) × S. aurantiaca (Sau; 2n=2x=24) was carried out at the flowering stage. This hybrid (Gve × Sau-1) was shown to have 44 chromosomes from Gve and 12 chromosomes from Sau by genomic in situ hybridization analysis. Gve×Sau-1 produced flowers in late June, whereas Gve and Sau did in early July and early June, respectively. Gve×Sau-1 showed a climbing habit as Gve did, and had vegetative shoots below the first flower. Plant height of Gve×Sau-1 was much higher than both parents. Gve×Sau-1 had sessile leaves with leaf tip tendrils as Gve did. Flowers of Gve×Sau-1 were pendulous and had undulate and reflexed petals like those of Gve, but the degree of petal reflection in Gve×Sau-1 was lower than in Gve. Flower color of Gve×Sau-1 was different from both parents: the petal center was bright red (JHS 0106) and the petal rim was light yellow (JHS 2504). Gve×Sau-1 had dehiscent anthers, and its pollen viability was 2.0% as assessed with acetocarmine staining. Thus Gve×Sau-1 was clearly distinguishable from the parents and had novel horticultural characteristics. Fertility restoration of Gve×Sau-1 through in vitro chromosome doubling is now in progress.
Kishimoto, T., Nakazawa, D., Sato, T., Saito, T., Amano, J., Kuwayama, S., Han, D.S., Nakano, M., Okuno, H., Godo, T. and Watanabe, Y. (2014). HORTICULTURAL CHARACTERIZATION OF AN INTERGENERIC HYBRID BETWEEN A SEPTAPLOID GLORIOSA CULTIVAR AND SANDERSONIA AURANTIACA. Acta Hortic. 1025, 51-56
tuberous plants, colchicaceous ornamental plant, chromosome doubling, ovule culture