Genome size influences plant growth and biodiversity responses to nutrient fertilization in diverse grassland communities

Morton, Joseph A. and Arnillas, Carlos Alberto and Biedermann, Lori and Borer, Elizabeth T. and Brudvig, Lars A. and Buckley, Yvonne M. and Cadotte, Marc W. and Davies, Kendi and Donohue, Ian and Ebeling, Anne and Eisenhauer, Nico and Estrada, Catalina and Haider, Sylvia and Hautier, Yann and Jentsch, Anke and Martinson, Holly and McCulley, Rebecca L. and Raynaud, Xavier and Roscher, Christiane and Seabloom, Eric W. and Stevens, Carly J. and Vesela, Katerina and Wallace, Alison and Leitch, Ilia J. and Leitch, Andrew R. and Hersch-Green, Erika I. (2024) Genome size influences plant growth and biodiversity responses to nutrient fertilization in diverse grassland communities. Plos Biology, 22 (12): e3002927. ISSN 1544-9173

Abstract

Experiments comparing diploids with polyploids and in single grassland sites show that nitrogen and/or phosphorus availability influences plant growth and community composition dependent on genome size; specifically, plants with larger genomes grow faster under nutrient enrichments relative to those with smaller genomes. However, it is unknown if these effects are specific to particular site localities with speciifc plant assemblages, climates, and historical contingencies. To determine the generality of genome size-dependent growth responses to nitrogen and phosphorus fertilization, we combined genome size and species abundance data from 27 coordinated grassland nutrient addition experiments in the Nutrient Network that occur in the Northern Hemisphere across a range of climates and grassland communities. We found that after nitrogen treatment, species with larger genomes generally increased more in cover compared to those with smaller genomes, potentially due to a release from nutrient limitation. Responses were strongest for C3 grasses and in less seasonal, low precipitation environments, indicating that genome size effects on water-use-efficiency modulates genome size–nutrient interactions. Cumulatively, the data suggest that genome size is informative and improves predictions of species’ success in grassland communities.