Stimulation of Rooting of Citrus Embryoids by Gibberellic Acid and Adenine Sulphate

Embryoids obtained from subcultured ovular callus of the Shamoutiorange (Citrus sinensis) were grown on Murashige and Tuckernutrient medium (BM) in the presence and absence of gibberellicacid (GA₂), adenine sulphate (ADS) and combinations of these.Both GA₂ and ADS stimulated significantly the rooting of smallembryoids with unorganized tissue, and larger embryoids withpartially developed root zones. Only large embryoids with fullydeveloped root zones rooted well on BM but better on BM+GA₂+ADS.Rooting was best on media containing 1 to 5 mg per 1 ADS, andthese two combined. The optimum sucrose concentrations were5 to 6 per cent. Shoot formation on embryoids prior to rootingcompletely inhibited rooting which is otherwise enhanced byGA₂+ADS. Filter-sterilized and autoclaved GA₂, showed similaractivity in rooting.