Data from: On-farm dynamic management of genetic diversity: the impact of seed diffusions and seed saving practices on a population-variety of bread wheat

Since the domestication of crop species, humans have derived specific varieties for particular uses, and shaped the genetic diversity of these varieties. Here, using an interdisciplinary approach combining ethnobotany and population genetics, we document the within-variety genetic structure of a population-variety of bread wheat (Triticum aestivum L.) in relation to farmers practices to decipher their contribution to crop species evolution. Using 19 microsatellites markers, we conducted two complementary graph theory-based methods to analyze population structure and gene flow among 19 sub-populations of a single population-variety (Rouge de Bordeaux, RDB). The ethnobotany approach allowed us to determine the RDB history including diffusion and reproduction events. We found that the complex genetic structure among the RDB sub-populations is highly consistent with the structure of the seed diffusion and reproduction network drawn based on the ethnobotanical study. This structure highlighted the key role of the farmer-led seed diffusion through founder effects, selection and genetic drift due to human practices. An important result is that the genetic diversity conserved on farm is complementary to that found in the genebank indicating that both systems are required for a more efficient crop diversity conservation.自作物物种驯化以来，人类已针对特定用途培育出专属品种，并塑造了这些品种的遗传多样性。本研究采用民族植物学与群体遗传学相结合的跨学科研究方法，针对普通小麦（Triticum aestivum L.）的一个种群-品种，解析其品种内的遗传结构与农户种植实践的关联，以阐明农户实践对作物物种演化的贡献。本研究使用19个微卫星标记（microsatellite markers），采用两种基于图论的互补分析方法，对单个种群-品种（Rouge de Bordeaux, RDB，中文常称波尔多红麦）的19个亚种群开展群体结构与基因流分析。通过民族植物学方法，我们得以厘清RDB的演化历史，包括种子传播与繁殖事件。研究发现，RDB亚种群间的复杂遗传结构，与基于民族植物学研究构建的种子传播与繁殖网络结构高度一致。该结构凸显了农户主导的种子传播的核心作用——农户的种植实践通过奠基者效应、人工选择与遗传漂变，塑造了该种群的遗传结构。本研究的一项重要结论为：农田原位保存的遗传多样性与种质库（genebank）保存的遗传多样性互为补充，这表明二者缺一不可，方可实现更为高效的作物遗传多样性保护。