Production and Evaluation of Haploid CallusCultures of Hibiscus sabdariffa L. (Karkadeh) Genotypes .

Abstract

Abstract This study aimed to establish and evaluate haploid callus cultures from two lines of Hibiscus sabdariffa L. plant .Anther and ovule cultures were studied for nutritional , floral bud developmental stage and hormonal requirements . The H.sabdariffa haploid callus was also studied for some of its morphological , physiological and anatomical features . Murashige and Skoog, B5 and White’s nutrient media were used to initiate calluses from anthers and unfertilized ovules of two H.sabdariffa lines . Anthers and ovules were excised from floral buds at 4 developmental stages. Auxins (IBA, NAA and2,4-D) were combined with cytokinins (BAP and Kinetin) at different concentrations and supplemented to MS medium for ovule callus initiation and embryo formation (embryogenesis). Nutritional studies to stimulate explants growth showed that Murashige and Skoog medium was superior to B5 and White’s media in callus initiation .The second stage of floral bud development was the most suitable for haploid callus initiation from ovule , while anther tissues at different stages were less responsive The other three stages of bud development were not suitable for callus initiation . Hormonal requirements of H.sabdariffa ovule callus were 10 mg/L NAA as auxin , combined with 12.5 mg/L BAP as a cytokinin .Other auxins (IBA and 2,4-D) and the cytokinin kinetin were less effective. Ovule callus showed faster growth as judged by size and fresh weight than that initiated from anther callus. Also , the anatomical study revealed high potentiality of ovule callus to differentiation, organogenesis and embryoid production .