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Interactions between plants and leaf herbivores have long been implicated as the major driver of plant secondary metabolite diversity. However, other plant-animal interactions, such as those between fruits and frugivores, may also be involved in phytochemical diversification. Using 12 species of Piper , we conducted untargeted metabolomics and molecular networking with extracts of fruits and leaves. We evaluated organ-specific secondary metabolite composition and compared multiple dimensions of phytochemical diversity across organs, including richness, structural complexity, and variability across samples at multiple scales within and across species. Plant organ identity, species identity, and the interaction between the two all significantly influenced secondary metabolite composition. Leaves and fruit shared a majority of compounds, but fruits contained more unique compounds and had higher total estimated chemical richness. While the relative levels of chemical richness and structural complexity across organs varied substantially across species, fruit diversity exceeded leaf diversity in more species than the reverse. Furthermore, the variance in chemical composition across samples was higher for fruits than leaves. By documenting a broad pattern of high phytochemical diversity in fruits relative to leaves, this study lays groundwork for incorporating fruit into a comprehensive and integrative understanding of the ecological and evolutionary factors shaping secondary metabolite composition at the whole-plant level.
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Data from: Interaction diversity explains the maintenance of phytochemical diversity
{"Abstract":["Original data and R code to accompany the manuscript: "Interaction diversity explains the maintenance of phytochemical diversity" by Susan R. Whitehead, Ethan Bass, Alexsandra Corrigan, André Kessler, and Katja Poveda Accepted for publication in Ecology Letters<\/p>\n\nAbstract: The production of complex mixtures of secondary metabolites is a ubiquitous feature of plants. Several evolutionary hypotheses seek to explain how phytochemical diversity is maintained, including the synergy hypothesis, the interaction diversity hypothesis, and the screening hypothesis. We experimentally tested predictions derived from these hypotheses by manipulating the richness and structural diversity of phenolic metabolites in the diets of eight plant consumers. Across 3940 total bioassays, there was clear support for the interaction diversity hypothesis over the synergy or screening hypotheses. The number of consumers affected by a particular phenolic composition increased with increasing richness and structural diversity of compounds. Furthermore, the bioactivity of phenolics was consumer-specific. All compounds tested reduced the performance of at least one consumer, but no compounds affected all consumers. These results show how phytochemical diversity may be maintained in nature by a complex selective landscape exerted by diverse communities of plant consumers.<\/p>\n\nhttps://github.com/WhiteheadLabVT/Phytochemical-Diversity-Experiment/releases/tag/v1.0.0<\/p>"]}
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- Award ID(s):
- 1856776
- PAR ID:
- 10429773
- Publisher / Repository:
- Zenodo
- Date Published:
- Edition / Version:
- v1.0.0
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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