Department of Biotechnology and Life Sciences (DBSV), University of Insubria, 21100 Varese, Italy.
Institute of Bioeconomy (IBE), Consiglio Nazionale Ricerche (CNR), 58022 Follonica, Italy.
Genes (Basel). 2024 Jul 1;15(7):866. doi: 10.3390/genes15070866.
The sweet chestnut ( Mill.) is subject to the progressive disappearance of its traditional chestnut groves. In the northern part of Italy, where distribution of the sweet chestnut is fragmented, many local varieties continue to be identified mostly by oral tradition. We characterised by SSRs eleven historically recognised varieties of sweet chestnut in the area surrounding Lake Como, with the goal of giving a genetic basis to the traditional classification. We performed classical analysis about differentiation and used Bayesian approaches to detect population structure and to reconstruct demography. The results revealed that historical and genetic classifications are loosely linked when chestnut fruits are just "castagne", that is, normal fruits, but increasingly overlap where "marroni" (the most prized fruits) are concerned. Bayesian classification allowed us to identify a homogeneous gene cluster not recognised in the traditional assessment of the varieties and to reconstruct possible routes used for the propagation of sweet chestnut. We also reconstructed ancestral relationships between the different gene pools involved and dated ancestral lineages whose results fit with palynological data. We suggest that conservation strategies based on a genetic evaluation of the resource should also rely on traditional cultural heritage, which could reveal new sources of germplasm.
甜栗（栗）正面临其传统栗树林不断消失的问题。在意大利北部，甜栗的分布较为分散，许多当地品种主要通过口头传统来识别。我们使用 SSR 对科莫湖周边地区的 11 种历史上公认的甜栗品种进行了特征描述，旨在为传统分类提供遗传基础。我们进行了关于分化的经典分析，并使用贝叶斯方法来检测种群结构和重建种群动态。结果表明，当栗果只是“castagne”（普通果实）时，历史和遗传分类是松散相关的，但当涉及到“marroni”（最珍贵的果实）时，它们的相关性越来越强。贝叶斯分类允许我们识别出一个在传统品种评估中未被识别的同质基因簇，并重建甜栗传播可能使用的途径。我们还重建了不同基因库之间的祖先关系，并对祖先谱系进行了时间测定，其结果与孢粉学数据相符。我们建议，基于资源遗传评估的保护策略也应该依赖于传统的文化遗产，这可能会揭示新的种质来源。
