Drought Stress Triggers Shifts in the Root Microbial Community and Alters Functional Categories in the Microbial Gene Pool

Abstract

Drought is a major threat to crop productivity and causes decreased plant growth, poor yields, and crop failure. Nevertheless, the frequency of droughts is expected to increase in the coming decades. The microbial communities associated with crop plants can influence how plants respond to various stresses; hence, microbiome manipulation is fast becoming an effective strategy for improving the stress tolerance of plants. The effect of drought stress on the root microbiome of perennial woody plants is currently poorly understood. Using Populus trees as a model ecosystem, we found that the diversity of the root microbial community decreased during drought treatment and that compositional shifts in microbes during drought stress were driven by the relative abundances of a large number of dominant phyla, including Actinobacteria, Firmicutes, and Proteobacteria. A subset of microbes, including Streptomyces rochei, Bacillus arbutinivorans, B. endophyticus, B. megaterium, Aspergillus terreus, Penicillium raperi, Trichoderma ghanense, Gongronella butleri, and Rhizopus stolonifer, was isolated from the drought-treated poplar rhizosphere soils, which have potentially beneficial to plant fitness. Further controlled inoculation experiments showed that the isolated bacterial and fungal isolates positively impacted plant growth and drought tolerance. Collectively, our results demonstrate the impact of drought on root microbiome structure and provide a novel example of manipulating root microbiomes to improve plant tolerance.

Effects of Water Loss Stress under Tidal Effects on the Epiphytic Bacterial Community of Sargassum thunbergii in the Intertidal Zone

“…For example, Bechtold et al ( 30 ) found that the microbial community diversity and composition of the abundance of dominant bacteria on forage grasses were significantly altered under drought conditions. Similar results were reported both in Populus trees ( 31 ) and in the peanut rhizosphere ( 32 ) under drought stress. In this study, high-throughput sequencing technology was used to explore the effects of water loss stress caused by tidal effects on the structure and function of the epiphytic bacterial community of S. thunbergii in the intertidal zone and to compare the different responses of the epiphytic bacterial communities of male and female algae to water loss stress.…”

Divergent microbial traits influence the transformation of living versus dead root inputs to soil carbon

“…Streptomycetes ) with lignocellulytic capabilities. This bolsters prior long-standing hypotheses and some recent work 54–56 showing that these taxa may be more resilient to drought conditions. In addition, STXM-NEXAFS spectra indicated a more plant-derived signature of mineral-associated SOC in the rhizosphere under drought, comparable with the detritusphere (Fig.…”

Rhizosphere soil bacterial communities and nitrogen cycling affected by deciduous and evergreen tree species

“…Drought significantly reduced SOM, TN, and of rhizosphere soils (Table ) and induced changes in the abundance, diversity, and network structure of the bacterial community in this study (Figures 1–3; Figure ). Nutrient competition among microbes and osmotic stress affects bacteria species (Chodak et al, 2015; Xie et al, 2021). The bacterial genera, for example, Arthrobacter and Bacillus , were reduced by drought, suggesting drought‐sensitive species belonging to the two genera were strongly inhibited by the declining water availability (Chodak et al, 2015; Xie et al, 2021).…”