Rapid transgenerational effects in Knautia arvensis in response to plant-community diversity

1. Plant-species persistence in natural communities requires coping with biotic and abiotic challenges. These challenges also depend on plant-community composition and diversity. Over time, biodiversity effects have been shown to be strengthened via increasing species complementarity in mixtures. Little is known, however, whether differences in community diversity and composition induce rapid transgenerational phenotypic adaptive differentiation during community assembly. We expect, altered plant-plant and other biotic interactions (mutualists or antagonists) in high vs. low diverse communities to affect immediate within- and between species-trait differentiations due to competition for light and nutrients. 2. Three years after the initiation of a large-scale, long-term biodiversity experiment in Jena, Germany, we tested for effects of varying experimental plant-community diversity (1–60 plant species; 1–4 plant functional groups) and composition (with or without legumes and/or grasses)...