Date palm agrobiodiversity (Phoenix dactylifera L.) in Siwa oasis, Egypt: combining ethnography, morphometry, and genetics

Date palm agrobiodiversity (Phoenix dactylifera L.) in Siwa oasis, Egypt: combining ethnography, morphometry, and genetics
by Vincent Battesti* & Muriel Gros-Balthazard*, Clémence Ogéron, Sarah Ivorra, Jean-Frédéric Terral & Claire Newton
(* contributed equally to this work)

a.k.a. [former title]: Date palms (Phoenix dactylifera L.) in Siwa oasis (Egypt): How ethnographic, morphometric, and genetic analyses together explain the local agrobiodiversity

Human Ecology journal, vol. 46 (4), August 2018, p. 529-546.
Online First: 20 June 2018
[Siwa #1]
ISSN 0300-7839 (Print) 1572-9915 (Online)
DOI: 10.1007/s10745-018-0006-y
On the Journal’s website: https://doi.org/10.1007/s10745-018-...
PDF File: https://hal.science/hal-01716788

– This is a sort of sequel to the article Siwa #0: The agrobiodiversity of the Date Palm (Phoenix dactylifera L.) in Siwa Oasis (Egypt): between what is said, written, and forgotten. It is followed by another article, Siwa #2 On the necessity of combining ethnobotany and genetics to assess agrobiodiversity and its evolution in crops: a case study on date palms (Phoenix dactylifera L.) in Siwa Oasis, Egypt, devoted to the confrontation of agrobiodiversity read by genetic tools and local categorization systems.

– Abstract:

The agrobiodiversity of Siwa oasis (Egypt), located at the crossroads of ancient Trans-Saharan routes, is evaluated in this article focusing on the date palm (Phoenix dactylifera L.), the oasis “ecosystem engineer”. This assessment confronts different ontologies: diversity as expressed and maintained by the folk categorization system of Siwa inhabitants (through the results of an ethnographical analysis) and diversity described by genetic sciences and a morphometric tool based on size and geometry of seeds. Beyond a simple instrumentalization of one discipline by another, this study offers an interdisciplinary space of mutual enrichment, with results that would otherwise have been inaccessible. It verified that some named types are true cultivars, sharing not only a formal identity, which matters for Isiwan people, but also a genetic identity. However, it also corroborates the existence of “ethnovarieties”, i.e. voluntary collections of multiple clones sharing phenotypic characteristics under a same local given name, suggesting the genetic richness is higher than the apparent agrobiodiversity estimated by a superficial ethnobotanical approach. Finally, this study offers new insights on the relative importance of feral and cultivated date palms.