Gros-Balthazard Muriel, Battesti Vincent, Ivorra Sarah, Paradis Laure, Aberlenc Frédérique, Zango Oumarou, Zehdi-Azouzi Salwa, Moussouni Souhila, Naqvi Summar Abbas, Newton Claire, Terral Jean-Frédéric
Center for Genomics and Systems Biology New York University Abu Dhabi Abu Dhabi United Arab Emirates.
Institut des Sciences de l'Évolution UMR 5554 CNRS/Université de Montpellier/IRD/EPHE CC065 Équipe Dynamique de la Biodiversité, Anthropo-écologie Université - Montpellier Montpellier Cedex 5 France.
Evol Appl. 2020 Feb 24;13(8):1818-1840. doi: 10.1111/eva.12930. eCollection 2020 Sep.
Crop diversity is shaped by biological and social processes interacting at different spatiotemporal scales. Here, we combined population genetics and ethnobotany to investigate date palm ( L.) diversity in Siwa Oasis, Egypt. Based on interviews with farmers and observation of practices in the field, we collected 149 date palms from Siwa Oasis and 27 uncultivated date palms from abandoned oases in the surrounding desert. Using genotyping data from 18 nuclear and plastid microsatellite loci, we confirmed that some named types each constitute a clonal line, that is, a true-to-type cultivar. We also found that others are collections of clonal lines, that is, ethnovarieties, or even unrelated samples, that is, local categories. This alters current assessments of agrobiodiversity, which are visibly underestimated, and uncovers the impact of low-intensity, but highly effective, farming practices on biodiversity. These hardly observable practices, hypothesized by ethnographic survey and confirmed by genetic analysis, are enabled by the way Isiwans conceive and classify living beings in their oasis, which do not quite match the way biologists do: a classic disparity of versus. categorizations. In addition, we established that Siwa date palms represent a unique and highly diverse genetic cluster, rather than a subset of North African and Middle Eastern palm diversity. As previously shown, North African date palms display evidence of introgression by the wild relative , and we found that the uncultivated date palms from the abandoned oases share even more alleles with this species than cultivated palms in this region. The study of Siwa date palms could hence be a key to the understanding of date palm diversification in North Africa. Integration of ethnography and population genetics promoted the understanding of the interplay between diversity management in the oasis (short-time scale), and the origins and dynamic of diversity through domestication and diversification (long-time scale).
作物多样性受到在不同时空尺度上相互作用的生物和社会过程的影响。在此，我们结合群体遗传学和民族植物学来研究埃及锡瓦绿洲的海枣（Phoenix dactylifera L.）多样性。通过对农民的访谈以及对田间实践的观察，我们从锡瓦绿洲收集了149株海枣，并从周边沙漠中废弃绿洲采集了27株野生海枣。利用来自18个核基因和质体微卫星位点的基因分型数据，我们证实了一些命名类型各自构成一个克隆系，即一个纯正品种。我们还发现，其他一些是克隆系的集合，即民族品种，甚至是不相关的样本，即地方类别。这改变了目前对农业生物多样性的评估，这种评估明显被低估了，并揭示了低强度但高效的农业实践对生物多样性的影响。这些几乎难以观察到的实践，由人种学调查推测并经基因分析证实，是由锡瓦人在其绿洲中构想和分类生物的方式促成的，这与生物学家的方式不太一样：这是一种典型的民间分类与科学分类的差异。此外，我们确定锡瓦海枣代表了一个独特且高度多样的基因簇，而不是北非和中东棕榈多样性的一个子集。如先前所示，北非海枣显示出被野生近缘种渗入的证据，并且我们发现，来自废弃绿洲的野生海枣与该物种共享的等位基因比该地区的栽培海枣更多。因此，对锡瓦海枣的研究可能是理解北非海枣多样化的关键。人种志与群体遗传学的整合促进了对绿洲中多样性管理（短时间尺度）与通过驯化和多样化产生的多样性起源及动态（长时间尺度）之间相互作用的理解。
