Environmental and serotiny data of Pinus halepensis

<p><span>Many plants undergo adaptation to fire. Yet, as global change is increasing fire frequency worldwide, our understanding of the genetics of adaptation to fire is still limited. </span><span>We studied the genetic basis of serotiny (the ability to disseminate seed exclusively after fire) in the widespread, pioneer Mediterranean conifer <em>Pinus halepensis</em> Mill., by linking individual variation in serotiny presence and level to fire frequency and to genetic polymorphism in natural populations. </span></p> <p><span>After filtering steps, 885 Single Nucleotide Polymorphisms (SNPs) out of 8,000 SNPs used for genotyping were implemented to perform an <em>in situ</em> association study between genotypes and serotiny presence and level. To identify serotiny-associated loci, we performed random forest analyses of the effect of SNPs on serotiny levels, while controlling for tree size, frequency of wildfires, and background environmental parameters.</span></p> <p><span>Serotiny showed a bimodal distribution, with serotinous trees more frequent in populations exposed to fire in their recent history. </span><span>Twenty-two</span><span> SNPs found in genes involved in stress tolerance were associated with presence-absence of serotiny while thirty-seven found in genes controlling for flowering were associated with continuous serotiny variation.</span></p> <p><span>This study </span><span>shows</span><span> the high potential of </span><em><span>P. halepensis</span></em><span> to adapt to changing fire regimes, benefiting from a large and flexibl</span><span>e</span> <span>genetic basis of trait variation</span><span>.</span></p>