Societal Impact Statement
The oasis of al-‘Ulā is subject to a vast development operation by the central government of the Saudi monarchy. Agriculture is not strictly speaking the first objective of this initiative, the emphasis being on tourism and thus on the vast historical heritage and landscape qualities of the region. Nevertheless, agriculture and, in particular, phoeniculture remain the main resource for the inhabitants. Characterizing the local date palm agrobiodiversity is key to the sustainable development of oases. In al-‘Ulā, documenting indigenous knowledge about the locally predominant barnī variety and characterizing its genetic integrity and mode of propagation represents the essential leverage needed by farm development project planners to develop local production.
Understanding how farmers name and categorize their crops in relation to the way they are propagated is critical for a proper assessment of agrobiodiversity. Yet, indigenous knowledge is often overlooked in genetic studies, which may result in an underestimation of crop diversity, thereby preventing its conservation and mobilization for developing sustainable agroecosystems.
Here, we focus on the barnī date palm variety, a local elite variety of al-‘Ulā oasis, Saudi Arabia. We conducted an ethnobotanical survey on local phoeniculture practices and generated whole-genome data to determine whether or not barnī palms are exclusively clonally (vegetatively) propagated. Further, we contrasted the genomes of barnī and two other palms from al-‘Ulā with 112 Phoenix spp. to provide an initial insight into date palm diversity in this oasis.
The survey reveals that the dates of the barnī palm bear distinct names, depending on their quality. Results show that barnī is a true-to-type cultivar, indicating clonal propagation by offshoots with name maintenance, even between distinct cultivating situations in al-‘Ulā and a nearby oasis. Nonetheless, it is distinct from the prominent barnī cultivated in Oman. Its ancestry is comparable to other West Asian date palms, but another palm from this oasis shows influence from North Africa.
What lies behind the cultivar name barnī in al-‘Ulā and further afield in the Arabian Peninsula has been deciphered through the key disciplinary combination of social anthropology and genetics. Future studies will provide additional insights into the original genetic make-up of this millennia-old oasis.
KAUST Repository Item: Exported on 2022-10-12
Acknowledgements: Funding is French Agency for AlUla Development(AFALULA). We are grateful to the farmers, who opened their gardens and farms to us, shared their knowledge and know-how, and offered us unfailing hospitality.
We thank Claire Newton for providing a sample; Marc Arnoux, Nizar Drou, Michael Dhar, and the New York University Abu Dhabi Bioinformatics Core for assistance with DNA sequencing and bioinformatic analyses; Luis Rivera Serna from the Center for Desert Agriculture at KAUST for assistance with bioinformatic analyses. This work was supported in part through the NYU IT High Performance Computing resources, services, and staff expertise. We are particularly grateful to Shenglong Wang for his unwavering support while using NYU cluster.
This work was funded by the French Agency for AlUla Development (AFALULA) with his Saudi partner the Royal Commission for AlUla (RCU) through a grant awarded to Vincent Battesti and Muriel Gros-Balthazard (project al-‘Ulā DPA: Ethnographic, genetic, and morphometric analyses of the date palm agrobiodiversity in al-‘Ulā oasis). We wish to thank them for their financial and logistic support, and in particular Elisabeth Dodinet and Stéphane Forman. Legally, the Royal Commission for AlUla is the owner and provider of the material.