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Summary The scope of plant control over its microbiome is a central question in evolutionary biology and agriculture. Leaf traits are known to shape pathogen colonization and disease development, but their impact on the broader community of largely non‐pathogenic fungi that colonize plant leaves remains an open question.We used reciprocal common gardens of the model tree,Populus trichocarpa(black cottonwood), to examine relationships between leaf traits and the leaf mycobiome in two strongly contrasting environments. We measured six leaf traits (stomatal length, stomatal density, carbon‐to‐nitrogen ratio, leaf thickness, leaf dry matter content, and specific leaf area) and used fungal marker gene sequencing to characterize leaf fungal communities for 57 tree genotypes replicated in one mesic and one xeric common garden (809 trees).Several leaf traits covaried with the leaf mycobiome, yet one relationship was paramount: plant genotypes with longer, sparser leaf stomata hosted a greater richness and diversity of more similar fungal species compared to plant genotypes with shorter, denser leaf stomata.These relationships, while modulated by the environment plants were sourced from and grown in, suggest that stomatal traits may be a general mechanism through which plants and the leaf mycobiome influence one another.
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Heterosis of leaf and rhizosphere microbiomes in field‐grown maize
Summary Macroorganisms’ genotypes shape their phenotypes, which in turn shape the habitat available to potential microbial symbionts. This influence of host genotype on microbiome composition has been demonstrated in many systems; however, most previous studies have either compared unrelated genotypes or delved into molecular mechanisms. As a result, it is currently unclear whether the heritability of host‐associated microbiomes follows similar patterns to the heritability of other complex traits.We take a new approach to this question by comparing the microbiomes of diverse maize inbred lines and their F1hybrid offspring, which we quantified in both rhizosphere and leaves of field‐grown plants using 16S‐v4 and ITS1 amplicon sequencing.We show that inbred lines and hybrids differ consistently in the composition of bacterial and fungal rhizosphere communities, as well as leaf‐associated fungal communities. A wide range of microbiome features display heterosis within individual crosses, consistent with patterns for nonmicrobial maize phenotypes. For leaf microbiomes, these results were supported by the observation that broad‐sense heritability in hybrids was substantially higher than narrow‐sense heritability.Our results support our hypothesis that at least some heterotic host traits affect microbiome composition in maize.
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- Award ID(s):
- 1656006
- PAR ID:
- 10368445
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 228
- Issue:
- 3
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 1055-1069
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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