Four decades of soil water stress history together with host genotype constrain the response of the wheat microbiome to soil moisture

Citation

Azarbad, H., Tremblay, J., Giard-Laliberté, C., Bainard, L.D., Yergeau, E. (2021). Four decades of soil water stress history together with host genotype constrain the response of the wheat microbiome to soil moisture. FEMS Microbiology Ecology, [online] 96(7), http://dx.doi.org/10.1093/FEMSEC/FIAA098

Plain language summary

Although occurring naturally in many environments, drought is globally increasing due to climate change. Drought has already taken a toll on global crop yields including drastic decreases in wheat yields. Soil and plant associated microorganism have the potential capability to enhance crop responses and mitigate the impact of drought. The objective of this study was to gain better insight into the how soil water stress history and crop varieties influence the response of microbial communities under short-term water stress. To address this, we investigated how plant breeding history (four wheat varieties; two with recognized drought resistance and two without) and soil water stress history (same wheat field soil from Saskatchewan with contrasting long-term irrigation) independently or interactively influenced the response of the bacterial and fungal microbiota to short-term decreases in soil water content. Our results revealed complex responses of the wheat-associated microbiome to short-term decreases in soil water content that are highly influenced by crop variety and soil water stress history. This suggests that predicting how crops will respond to climate change stressors will also require an understanding of its associated microbiome.

Abstract

There is little understanding about how soil water stress history and host genotype influence the response of wheat-associated microbiome under short-term decreases in soil moisture. To address this, we investigated how plant breeding history (four wheat genotypes; two with recognized drought resistance and two without) and soil water stress history (same wheat field soil from Saskatchewan with contrasting long-term irrigation) independently or interactively influenced the response of the rhizosphere, root and leaf bacterial and fungal microbiota to short-term decreases in soil water content (SWC). We used amplicon sequencing (16S rRNA gene for bacteria and ITS region for fungi) to characterize the wheat microbiome. Fungal and bacterial communities responses to short-term decreases in SWC were mainly constrained by soil water stress history, with some smaller, but significant influence of plant genotype. One exception was the leaf-associated fungal communities, for which the largest constraint was genotype, resulting in a clear differentiation of the communities based on the genotype's sensitivity to water stress. Our results clearly indicate that soil legacy does not only affect the response to water stress of the microbes inhabiting the soil, but also of the microorganisms more closely associated with the plant tissues, and even of the plant itself.

Publication date

2021-01-01

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