Hyphaene thebaica (L.) Mart., commonly known as doum palm, is a culturally, nutritionally, and medicinally valuable (yet underutilized) species predominantly found in arid and semi-arid regions of Africa and the Middle East. Despite its ecological and economic potential, no standardized or comprehensive in vitro propagation protocol has been previously established for this species. Traditional propagation methods, primarily via seeds, are constrained by slow germination, long juvenile phases, and genetic heterogeneity. Therefore, the development of reliable tissue culture techniques is essential for the species' large-scale propagation, conservation, and genetic enhancement.
This review presents, for the first time, a scientific synthesis and evaluation of in vitro culture strategies for Hyphaene thebaica, based on original research findings and emerging data. It explores the use of various explants, including seed-derived radicles, root tips, and floral tissues, in initiating callus, shoot, and root formation. The influence of key factors such as plant growth regulators (e.g., 2,4-D, IBA, BAP, 2iP), carbon sources, and culture media compositions (e.g., MS, B5) is discussed in detail. Special emphasis is placed on the successful induction of embryogenic callus and somatic embryos from female inflorescences, marking a novel achievement in H. thebaica micropropagation.
Additionally, the review addresses challenges such as phenolic compound exudation, tissue browning, and somaclonal variation, offering practical mitigation strategies. This pioneering work lays the foundation for future conservation, genetic improvement, and commercial exploitation of H. thebaica through plant biotechnology.