Phylogenetic Analysis of Pleurotus Tuber-Regium Across Selected African Regions

Abstract

Pleurotus tuber-regium, the King Tuber Oyster mushroom, is an edible and medicinal macrofungus widely distributed across tropical and subtropical Africa. Despite its nutritional and therapeutic significance, limited molecular data exist on its phylogenetic diversity across the continent. This study investigated the evolutionary relationships of P. tuber-regium isolates from selected African regions using Internal Transcribed Spacer (ITS) gene sequences retrieved from the NCBI GenBank database. A total of thirty-six sequences were analyzed, representing isolates from Nigeria, Ghana, Cameroon, Madagascar, and South Africa. Multiple sequence alignment was performed in Geneious version 9.1 using the MUSCLE algorithm, and phylogenetic reconstruction was conducted with the Neighbor-Joining method under the Tamura–Nei model. The aligned dataset had a total length of 423 bp, with 93.6% conserved sites and an overall pairwise identity of 99.5%, indicating high genetic stability. The phylogenetic tree comprised 41 nodes and 36 tips, revealing minimal genetic divergence among most isolates. Strains from West and Central African formed two tightly clustered subclades, whereas isolates from Madagascar and South Africa appeared as early-diverging lineages, suggesting minor regional differentiation potentially linked to ecological adaptation. Overall, the results demonstrate low intra-continental variation and a single, broadly distributed African lineage of P. tuber-regium. The strong sequence conservation across diverse ecological zones implies potential similarity in metabolite composition and mycochemical profiles. However, the scarcity of genomic and complementary molecular data from Eastern and Southern Africa highlights the need for expanded sampling and multi-loci phylogenetic studies to refine understanding of the species’ evolutionary and biochemical diversity.