Crossability Studies among Twenty Accessions of Roselle (Hibiscus sabdariffa L.)

Increasing exploitation of roselle (Hibiscus sabdariffa L.) and its products require that commercial varieties with superior attributes are developed to replace landrace varieties and to meet the growing demand for commercial-scale cultivation of the crop. In this study, twenty landrace varieties of roselle collected from three geographical regions of Ghana were artificially crossed in a pairwise mating scheme. The aim was to obtain relevant information pertaining to fertility status and extent of crossability among the accessions to facilitate breeding of improved varieties. Attempts at hybridisation were made both between and among 6 accessions of Hibiscus sabdariffa var Altissima and 14 accessions of Hibiscus sabdariffa var Sabdariffa. Crosses between accessions of Hibiscus sabdariffa var Altissima and Hibiscus sabdariffa var Sabdariffa yielded no hybrids, suggestive of a crossability barrier between the two mating groups. All intra-varietal crosses involving accessions of Hibiscus sabdariffa var Altissima were successful regardless of direction of cross while only few of the crosses among those of Hibiscus sabdariffa var Sabdariffa produced successful hybrids. Also fertility estimates of members of Hibiscus sabdariffa var Altissima were significantly higher (30.00%-80.00%) compared to those of var Sabdariffa (0.00%-43.00%). This implies that complete pairwise design could be used for intra-varietal crosses involving accessions of Hibiscus sabdariffa var Altissima, whereas only a partial pairwise design is feasible for members of Hibiscus sabdariffa var Sabdariffa.