Climate-driven divergence in plant-microbiome interactions generates range-wide variation in bud break phenology

Ian M Ware,Zamin K Yang,Jennifer A Schweitzer,Michael E Van Nuland,Joseph K Bailey,Christopher W Schadt

doi:10.1038/s42003-021-02244-5

Abstract

Soil microbiomes are rapidly becoming known as an important driver of plant phenotypic variation and may mediate plant responses to environmental factors. However, integrating spatial scales relevant to climate change with plant intraspecific genetic variation and soil microbial ecology is difficult, making studies of broad inference rare. Here we hypothesize and show: 1) the degree to which tree genotypes condition their soil microbiomes varies by population across the geographic distribution of a widespread riparian tree, Populus angustifolia; 2) geographic dissimilarity in soil microbiomes among populations is influenced by both abiotic and biotic environmental variation; and 3) soil microbiomes that vary in response to abiotic and biotic factors can change plant foliar phenology. We show soil microbiomes respond to intraspecific variation at the tree genotype and population level, and geographic variation in soil characteristics and climate. Using a fully reciprocal plant population by soil location feedback experiment, we identified a climate-based soil microbiome effect that advanced and delayed bud break phenology by approximately 10 days. These results demonstrate a landscape-level feedback between tree populations and associated soil microbial communities and suggest soil microbes may play important roles in mediating and buffering bud break phenology with climate warming, with whole ecosystem implications.

Highlights

Soil microbiomes are rapidly becoming known as an important driver of plant phenotypic variation and may mediate plant responses to environmental factors
We show that the soil microbiome response to trees varied by population, indicating that the soil microbial community turnover in response to tree conditioning varied across the geographic distribution and genetic composition of P. angustifolia (Fig. 2c, Supplemental Table 3, and Supplemental Data 5)
As the soil microbiome varies in response to tree conditioning locally and across sites, these results provide a foundation for further studies separating the biotic and abiotic factors that drive soil microbiome structure and function across these landscapes in the western United States

Summary

Introduction

Soil microbiomes are rapidly becoming known as an important driver of plant phenotypic variation and may mediate plant responses to environmental factors. We hypothesize the following: (1) the degree tree genotypes condition their soil microbiomes varies by population; (2) geographic dissimilarity in soil microbiomes among populations is influenced by both abiotic and biotic environmental variation; and (3) soil microbiomes that vary in response to abiotic and biotic factors can change plant foliar phenology Consistent with these hypotheses, we show that soil microbiomes vary along a geographic climate gradient, respond to intraspecific variation at the tree genotype and population level, and experimentally show that this variation influences leaf bud break phenology, all of which can have large consequences for ecosystem productivity

Methods

Results

Conclusion