Argane Genetics and Genomics

Argania spinosa plays an important socioeconomic and ecologic role in different contrast situations like the arid zone located in the midwestern Morocco. This tree is used as a food and feed and as a resource for both pharmaceutical and cosmetic compounds. In the last decades, this genetic resource has faced significant threats from climate change, environmental factors, and human overexploitation. Argane tree genetics and genomics knowledge will help in counteracting these challenges. Studies have been undertaken to determine the Argane tree’s genetic diversity and depict ecological and sustainability concerns using morphological, biological, biochemical, and standardized molecular marker techniques. The development of affordable next-generation sequencing technologies allowed the sequencing and assembly of the A. spinosa genome using a hybrid de novo assembly approach combining short (Illumina) and long (PacBio) sequencing reads. The final draft genome comprises 75,327 scaffolds totaling 671 Mb. The 158,848 bp full genome of A. spinosa chloroplast (cp) was also assembled and annotated. This Argania spinosa reference genome constitutes a first initiative of the International Argania Genome Consortium toward a global integrative omics approach to bring insight into the biology and evolution of the Argane tree. Metabolic profiling studies on Argania fruit extracts have been conducted to extend the limit of biochemical detection. Prospective research will focus on transcriptome analysis for the sake of improving the prediction-based structural annotation of the genome and to understand the regulation of the genome expression. These genomics studies will facilitate efficient conservation of this endangered endemic tree and may enable genome-assisted cultivar breeding for genetic improvement and adaptation.