A phylogenomic approach reveals a low somatic mutation rate in a long-lived plant

Abstract

Somatic mutations can have important effects on the life history, ecology, andevolution of plants, but the rate at which they accumulate is poorly under-stood and difficult to measure directly. Here, we develop a method tomeasure somatic mutations in individual plants and use it to estimate thesomatic mutation rate in a large, long-lived, phenotypically mosaicEucalyp-tus melliodoratree. Despite being 100 times larger thanArabidopsis,this treehas a per-generation mutation rate only ten times greater, which suggeststhat this species may have evolved mechanisms to reduce the mutationrate per unit of growth. This adds to a growing body of evidence that illu-minates the correlated evolutionary shifts in mutation rate and life history in plants