Warming and drought stress in plants with contrasting functional strategies induce different phenotypic variability in their offspring

Abstract

Phenotypic plasticity, both within and across generations, is a mechanism by which plant species respond to changing environmental conditions. This is particularly relevant in a context of global change since organisms face rapid variations of climatic conditions to which should adjust and adapt. Specifically, plasticity across generations is receiving special attention, but the understanding of key aspects, such as the environmental conditions in which it occurs or the role that different functional groups might play in this process, remains understudied. Here, we investigated the magnitude and variability in the responses of herbaceous plant species with contrasting functional strategies to two main climatic stressors (warming and drought), analyzing the heritability of these responses from maternal plants to their offspring. With this aim, we conducted field surveys and greenhouse experiments with five co-occurring dominant herbaceous species of Mediterranean rangelands and measured their performance in terms of growth, reproduction and survival in response to increased temperature and decreased water availability. We found that resource-acquisitive species tended to show greater sensitivity and phenotypic variability in response to climatic treatments. However, the opposite trend was observed in the next generation, presenting the offspring of conservative species a high phenotypic variability when comparing seeds coming from mother plants exposed to different climatic scenarios. Our results suggest that the effect that maternal environment have on offspring performance vary in different functional groups of plants and its role in a context of adaptation to climate change is discussed.