Application of SRAP Markers to Identify Gender and Species in Genus Ephedra Tourn. ex L.

Background: The genus Ephedra (Ephedraceae) is a dioecious gymnosperm, where female individuals produce the pharmacologically active ephedrine alkaloids. Identifying the sex of specimens without reproductive cones is challenging due to their xeromorphic and morphological similarity. The challenges in sex identification complicate conservation and propagation efforts. Methods: Sequence-Related Amplified Polymorphism (SRAP) markers were applied to distinguish genders in five Ephedra species, particularly the vegetative branches, as well as powdered and fragmented specimens. The fresh material for the five studied Ephedra species and two sexes per species (totaling 10 samples; 5 females & 5 males) was collected from Sinai, Egypt. Results: The SRAP marker results revealed an exclusively male-specific band, and this is not applicable in females in the studied species. The applied SRAP markers grouped males and females in different UPGMA clusters and proved their efficiency in distinguishing between males and females in the five studied species. The Polymorphic Information Content (PIC) values are low (0.16–0.38); this suggests moderate genetic diversity between the females of the studied species, reflecting slow evolutionary rates. Conclusions: The SRAP markers are efficient for identifying Ephedra species at the species and gender levels, even in the absence of sex organs and molecular sequences. Recommendation: This study recommends the use of SRAP markers for conserving and propagating female plants for ephedrine production and suggests sequencing a 95 bp male-specific band to determine if it corresponds to a known sex-linked gene.