Data from: In situ genetic association for serotiny, a fire-related trait, in Mediterranean maritime pine (Pinus pinaster Aiton)

Wildfire is a major ecological driver of plant evolution. Understanding the genetic basis of plant adaptation to wildfire is crucial, because impending climate change will involve fire regime changes worldwide. We studied the molecular genetic basis of serotiny, a fire-related trait, in Mediterranean maritime pine using association genetics. A single nucleotide polymorphism (SNP) set was used to identify genotype : phenotype associations in situ in an unstructured natural population of maritime pine (eastern Iberian Peninsula) under a mixed-effects model framework. RR-BLUP was used to build predictive models for serotiny in this region. Model prediction power outside the focal region was tested using independent range-wide serotiny data. Seventeen SNPs were potentially associated with serotiny, explaining approximately 29% of the trait phenotypic variation in the eastern Iberian Peninsula. Similar prediction power was found for nearby geographical regions from the same maternal lineage, but not for other genetic lineages. Association genetics for ecologically relevant traits evaluated in situ is an attractive approach for forest trees provided that traits are under strong genetic control and populations are unstructured, with large phenotypic variability. This will help to extend the research focus to ecological keystone non-model species in their natural environments, where polymorphisms acquired their adaptive value.

野火是驱动植物演化的重要生态因子。阐明植物对野火适应性的遗传基础至关重要，因为即将到来的气候变化将引发全球范围内的火制度变化。本研究采用关联遗传学方法，对地中海海岸松的火相关性状——闭萌性（serotiny）的分子遗传基础展开分析。我们利用单核苷酸多态性（single nucleotide polymorphism, SNP）标记集，在混合效应模型框架下，对伊比利亚半岛东部的无遗传结构自然海岸松种群开展了原位基因型-表型关联分析；同时采用RR-BLUP方法构建了该区域海岸松闭萌性的预测模型，并借助独立获取的全分布区闭萌性数据，测试了模型在研究区域外的预测能力。研究共鉴定出17个与闭萌性潜在相关的SNP位点，这些位点解释了伊比利亚半岛东部种群中该性状约29%的表型变异。在同一母系谱系的邻近地理区域中，模型展现出相似的预测能力，但在其他遗传谱系中则未观测到类似效果。对于森林树种而言，若目标性状受强遗传控制、种群无遗传结构且表型变异丰富，原位开展生态相关性状的关联遗传学研究是极具价值的研究路径。该思路有助于将研究拓展至自然环境中的生态关键非模式物种，而这些物种中的多态性正是在自然选择过程中获得了适应性价值。