Epigenetics: a potential mechanism for clonal plant success

Clonality in plants is widespread and includes species that span temporally and spatially heterogeneous environments. Yet, theory predicts that clonally reproducing plants evolve at slower rates, risk accumulating more mutations than sexuals, and potentially lack the benefits of DNA repair mechanisms afforded by meiosis. Does the apparent success of clonal plants contradict the severe costs of clonal reproduction suggested by theory? We examine how epigenetics may confer ecological advantages to clonal plants that could outweigh these evolutionary costs. Relying to various degrees on vegetative reproduction, the capacity to conserve or reverse gene regulation changes over cell divisions has clear potential for optimization of plasticity and acclimation in response to environmental variation encountered. Clonal plants may be one of the best examples of organisms taking advantage of epigenetic acclimation as an alternative to the slower mechanisms of adaptation through natural selection. If epigenetic processes are important in matching organismal response to the environment, this may prove to be a mechanism that will buffer plants against the challenges of current and future rapid environmental changes.