Interactions between the soil bacterial community assembly and gene regulation in salt‐sensitive and salt‐tolerant sweet sorghum cultivars

Abstract

Complex bacterial communities in the rhizosphere play a crucial role in plant growth and stress tolerance. These communities vary across cultivars and external environments. However, the influences of salt stress on the structural composition of bacterial microbiome and gene expression of salt‐sensitive and salt‐tolerant sweet sorghum (Sorghum bicolor L. Moench) cultivars have not been studied sufficiently. Here, we employed a combination of 16S rRNA gene profiling and RNA‐seq analysis to characterize changes in root‐associated microbiomes and determine differentially expressed genes (DEG) in the roots of salt‐tolerant M‐81E and salt‐sensitive 'Roma' var. sweet sorghum cultivars under soil conditions with/without salinity. Results revealed that the two contrasting sweet sorghum genotypes selectively filtered and recruited distinct root microbiota in response to salt stress. M‐81E‐enriched bacterial taxa were more diverse and exhibited a higher abundance of metabolic functions than Roma‐enriched taxa. M‐81E‐associated bacterial co‐occurrence networks were more complex and harboured more positive links than Roma‐associated bacterial networks. Furthermore, nine DEG were identified as core salt‐responsive genes and were central to the salt tolerance of sweet sorghum. Correlation analysis revealed that the expression of HSP70, a molecular chaperone, is linked to the recruitment of numerous M‐81E‐enriched bacteria; their relationship needs further exploration. The study supplements the comprehension of the potential role of host–microbe interactions in the response of sweet sorghum to salt stress.

Interaction between rhizobacterial community assembly and host responses determines poplar salt tolerance

“…2b and c). The host genotype is an important impetus of microbial community composition, and salt-tolerant cultivars can enlist certain bacterial taxa in saline soil (Wu et al 2022;Li et al 2021). Using LEfSe analysis, we found that OTUs in Hydrogenophaga and Pseudomonas were abundant in the SXY rhizosphere (Fig.…”

“…Cyanobacteria and Acidobacteria have been shown to increase while Actinobacteria and Chloro exi decrease in the groundnut rhizosphere upon salt stress (Xu et al 2020). The abundance of Actinobacteria and Gemmatimonadetes is elevated in the rhizosphere of salt-tolerant sweet sorghum, while Bacteroidetes and Firmicutes accumulate in the rhizosphere of sensitive cultivars (Wu et al 2022). Recently, Yuan et al…”

“…PGPRs, including Azospirillum brasilense, Pseudomonas uorescens and Achromobacter piechaudii, play crucial roles in enhancing the salt tolerance of host plants (Hamdia et al 2004; Saravanakumar and Samiyappan 2007; Mayak et al 2004) by improving nutrition absorption, solubilizing phosphate, elevating 1-aminocyclopropane-1-carboxylic acid (ACC)-deaminase activity, producing siderophores, phytohormones and exopolysaccharides, and activating host antioxidant genes (Kumari et al 2015;Nadeem et al 2016;Gururani et al 2013). Salt stress in uences soil microbial diversity and leads to microbiome reassembly in plants (Gao et al 2021;Wu et al 2022; Singh 2016). Cyanobacteria and Acidobacteria have been shown to increase while Actinobacteria and Chloro exi decrease in the groundnut rhizosphere upon salt stress (Xu et al 2020).…”

Interaction between rhizobacterial community and host root determines poplar salt tolerance

“…PGPRs, including Azospirillum brasilense , Pseudomonas fluorescens , and Achromobacter piechaudii , play crucial roles in enhancing the salt tolerance of host plants (Hamdia et al, 2004; Mayak et al, 2004; Saravanakumar & Samiyappan, 2007) by improving nutrition absorption, solubilizing phosphate, elevating 1‐aminocyclopropane‐1‐carboxylic acid (ACC)‐deaminase activity, producing siderophores, phytohormones and exopolysaccharides, and activating host antioxidant genes (Gururani et al, 2013; Kumari et al, 2015; Nadeem et al, 2016). Salt stress influences soil microbial diversity and leads to microbiome reassembly in plants (Gao et al, 2021; Singh, 2016; Wu et al, 2022). Cyanobacteria and Acidobacteria increased while Actinobacteria and Chloroflexi decreased in the groundnut rhizosphere upon salt stress (Xu et al, 2020).…”

“…Cyanobacteria and Acidobacteria increased while Actinobacteria and Chloroflexi decreased in the groundnut rhizosphere upon salt stress (Xu et al, 2020). The abundance of Actinobacteria and Gemmatimonadetes elevated in the rhizosphere of salt-tolerant sweet sorghum, while Bacteroidetes and Firmicutes accumulated in the rhizosphere of sensitive cultivars (Wu et al, 2022). Recently, Yuan et al (2016) used the rhizosphere microbiome of the halophyte Suaeda salsa to help non-host rice withstand saline conditions.…”