Genotype-dependent responses and activated charcoal influence the in vitro development of oil palm (Elaeis guineensis Jarq.) emblings

Abstract Elaeis guineensis Jacq. (Arecaceae), commonly known as oil palm, is a major oilseed crop with wide applications in the food, cosmetic, and biofuel industries. Based on this, many somatic embryogenesis systems have been developed to enable clonal propagation. However, rooting responsiveness and acclimatization success are dependent on the genotype, which has been exhibiting low responsiveness. This study evaluated the in vitro performance of oil palm emblings from different genotypes in response to activated charcoal. Four genotypes (AM-05, AM-21, AM-29, and AM-33) were cultured under four activated charcoal concentrations (1.0, 2.0, 3.0, and 4.0 g L⁻¹) and in a charcoal-free control. Viable emblings were obtained for all genotypes, although protocol adjustments are required for less responsive materials. Genetically related genotypes exhibited superior development, suggesting a parental effect. Embling’s elongation was more effective at low concentrations or in the absence of activated charcoal. Furthermore, the addition of 2.8 g L⁻¹ activated charcoal to the culture medium enhanced secondary somatic embryogenesis, resulting in increased embling production. Additionally, the controlled conditions of in vitro cultivation, combined with activated charcoal, promoted anatomical changes, including reduced foliar and root structures and aerenchyma formation. These findings support the stage-specific use of activated charcoal as a practical strategy to improve the efficiency of E. guineensis clonal propagation through somatic embryogenesis.