Microbiota community assembly in wild rice (Oryza longistaminata) in response to drought stress shows phylogenetic conservation, stochasticity, and aboveground-belowground patterns

Abstract

<jats:title>Abstract</jats:title> <jats:p>Background Drought is a global environmental stress that limits crop yields. Microbial communities control many biogeochemical processes, and a predictive understanding of how crop microbial communities assemble in response to drought stress is central to addressing the challenges caused by drought. Little is known about the microbiome assembly processes in rice-ecosystems, particularly with regard to their environmental adaptation. Wild rice may serve as a source of superior drought tolerance candidate for rice breeding. There is an urgent need to explore wild rice resistance mechanisms to drought stress. Here, we evaluated the effect of drought stress on the microbial community recruitment and assembly in the endosphere (leaf, stem, and root) and rhizosphere of <jats:italic>Oryza longistaminata</jats:italic>. Results Species replacement was the dominant process shaping microbial community composition under drought stress. <jats:italic>O. longistaminata</jats:italic> recruited the phyla Actinobacteria and Fusobacteria, the genus <jats:italic>Streptomyces</jats:italic>, and phototrophic prokaryotes to improve its fitness. The host exerted strong effects on microbiome assembly, and the responses of the microbial community structure to the drought environment showed above- and belowground patterns. Drought reduced taxonomic α-diversity and destabilized co-occurrence network properties in the leaves and stems, but not in the roots and rhizosphere. Drought promoted the restructuring and strengthening of belowground network links to more strongly interconnect network properties. The drought response of the microbiome was phylogenetically conserved. Stochastic (neutral) processes acted on microbial community reassembly in response to drought stress across all four compartments. Conclusions Our results provide new insight into the mechanisms through which drought alters microbial community assembly in drought-tolerant wild rice and reveal a potential strategy for manipulating plant microbiomes to improve crop fitness.</jats:p>

Drought Stress Increases the Complexity of the Bacterial Network in the Rhizosphere and Endosphere of Rice (Oryza sativa L.)

“…This suggests that microorganisms may strengthen their collaboration in response to environmental pressures during drought conditions. A similar pattern was observed in a study on the rhizosphere and endosphere bacteria of wild rice (Oryza longistaminata) [35]. Yuan et al [36] also noted that prolonged warming coupled with decreasing soil moisture content amplified the complexity of soil bacterial co-occurrence networks, particularly the proportion of positive links.…”