Specialized Microbiome of a Halophyte and its Role in Helping Non-Host Plants to Withstand Salinity

Abstract

Root microbiota is a crucial determinant of plant productivity and stress tolerance. Here, we hypothesize that the superior halo-tolerance of seepweed Suaeda salsa is tightly linked to a specialized belowground microbiome. To test this hypothesis, we performed a phylogenetic trait-based framework analysis based on bacterial 16S rRNA gene and fungal nuclear rRNA internal transcribed spacer profiling. Data showed that the dominant α-proteobacteria and γ-proteobacteria communities in bulk soil and root endosphere tend to be phylogenetically clustered and at the same time exhibit phylogenetic over-dispersion in rhizosphere. Likewise, the dominant fungal genera occurred at high phylogenetic redundancy. Interestingly, we found the genomes of rhizospheric and endophytic bacteria associated with S. salsa to be enriched in genes contributing to salt stress acclimatization, nutrient solubilization and competitive root colonization. A wide diversity of rhizobacteria with similarity to known halotolerant taxa further supported this interpretation. These findings suggest that an ecological patterned root-microbial interaction strategy has been adopted in S. salsa system to confront soil salinity. We also demonstrated that the potential core microbiome members improve non-host plants growth and salt tolerance. This work provides a platform to improve plant fitness with halophytes-microbial associates and novel insights into the functions of plant microbiome under salinity.

Halophytes in biosaline agriculture: Mechanism, utilization, and value addition

“…brachiata and showed that the halobacteria were involved in indole acetic acid production, phosphate solubilization, and 1‐aminocyclopropane‐1‐carboxylic acid deaminase activity. In a recent study, Yuan et al () demonstrated that the microbiome of Suaeda salsa could help to improve nonhost plants growth and salt tolerance.…”

Efficient colonization of the endophytes Herbaspirillum huttiense RCA24 and Enterobacter cloacae RCA25 influences the physiological parameters of Oryza sativa L. cv. Baldo rice

“…The area of BNF research has been expanded by the discovery of N-fixing bacterial endophytes in non-nodulating plants. Bacterial endophytes promote plant growth through nitrogen fixation, phytohormone production, nutrient acquisition and by conferring tolerance to abiotic and biotic stresses (Haney et al, 2015;Berg et al, 2016;Yuan et al, 2016;Santoyo et al, 2017). They most often inhabit the plant intercellular spaces, which are abundant in carbohydrates, amino acids and inorganic nutrients (Compant et al, 2011;Liu et al, 2017).…”

Variation of the Bacterial Communities in the Rhizosphere of Three Species of the Genus Tagetes (Marigold) Over Time

“…For example, Shi et al (2015) analyze the changes in microbial rhizosphere communities of the annual grass Avena fatua in two growing sessions and found that in spite of the different starting communities in both seasons, the successional patterns were similar and the final communities were very similar. On the other hand, Yuan et al (2016) analyzed the rhizosphere of the seepweed Suaeda salsa and found that both phylogenetic clustering (abiotic factors) and overdispersion (biotic factors) are involved in the high tolerance to salinity in this plant species. The genus Tagetes has been characterized as exuding allelopathic compounds of the thiophenes type which have a nematocide function that has been demonstrated in both field and laboratory (Riga et al, 2005).…”