Oral Paper

         Population Genetics/Genomics

Ecological Bastion and Iconic Cultural Food: Conservation Genomics of the Argan Tree

Presenting Author
Madeline Slimp
Description
The Argan tree (Sideroxylon spinosum, Family: Sapotaceae), is an iconic keystone species endemic to Morocco, where it serves as one of the only ecological barriers to the encroaching Sahara desert. A number of local livelihoods, predominantly those of Moroccan women, depend on the tree for producing edible oil used in Moroccan cuisine. This cultural significance is recognized worldwide, with the Argan tree being added to UNESCO’s Representative List of the Intangible Cultural Heritage of Humanity in 2014.  Additionally, Argan oil is being exported out of Morocco for global use as an ingredient in cosmetic and personal care products, with the Argan oil market estimated at nearly 300 Million USD.  In the past century, forest cover has halved, with some areas seeing a 66% reduction in argan tree density. In 1998, UNESCO erected the Arganeraie Biosphere Reserve, designed around the declining argan tree and its reliant rural communities. Sideroxylon spinosum has been recently categorized as ‘Vulnerable’ on the IUCN Red List, with major threats reported as overgrazing, logging, land clearing for agriculture and urban development, and increased aridity. Despite being at evidenced risk, the Argan tree has been overlooked for broad genome approach research, which could be beneficial for conservation, management, and improvement. In this presentation we describe our recent effort to characterize the population genomics of Sideroxylon spinosum using the Angiosperms353 target capture kit. This study will be the first large-scale within species population genomics study using Angiosperms353. The outcome of this project is to quantify and map genetic qualities of current Argan tree populations across Morocco for the purpose of informing future biobanking efforts to preserve current genetic diversity. The information generated by this project could inform land managers about sources of genetic variability to integrate into current argan forests based on ancestral population data paired with existing ecotype identifications. We determine the number of ancestral genetic populations across the country of Morocco and compare this with previous microsatellite and ISSR marker papers. We calculate ‘Genetic health’ metrics such as Tajima’s D, heterozygosity, inbreeding coefficient and used to identify regions of Morocco that are at the greatest need for conservation effort for the Argan tree.