The Role of Silver Thiosulphate and Glutamine on Direct Organogenesis of Two Date Palm (Phoenix dactylifera L.) Cultivars

Abstract

This study was conducted to examine the effect of silver thiosulphate (STS) and glutamine at various concentrations on direct organogenesis and shoots multiplication of date palm (Phoenix dactylifera L.) Barhi and Maktom cvs. Shoot tip quarters were cultured in vitro on modified MS medium supplemented with 2.0 mg/1 2ip, 1.0 mg/1 BA, 1.0 mg/1 NAA and 1.0 mg/1 NOA with various concentrations of STS (30, 60, 90 and 120 µM) and glutamine at (0.35, 0.70, 1.4 and 2.1 mM). The same concentrations were used in multiplication stage with medium supplemented with 4.0 mg/1 2ip, 2 mg/1 BA, 1.0 mg/1 NAA and 1.0 mg/1 NOA. Results indicated that the addition of STS at 90 µM and glutamine at 0.7 mM gave the best result for adventitious bud formation after 16 weeks (8.1 and 9.4 buds per explant for Barhi and Maktom respectively). Subculturing of these buds on agitated liquid MS medium with 90 µM STS and 1.4 mM glutamine gave the highest average of shoots number (12.5 and 14.7 shoots for Barhi and Maktom respectively). Maktom cultivar produced more buds and shoots than Barhi irrespective of the level of STS and glutamine. Shoots were rooted and successfully transferred to soil. These results confirm the importance of supplementing plant culture media of date palm cvs. Barhi and Maktom with both silver thiosulphate and glutamine in order to optimize and improve the clonal propagation protocol for these two cultivars.