Rhizosheath-associated Massilia contributes to maize growth heterosis

ABSTRACT:

Heterosis, or hybrid vigor, refers to the phenomenon where F1 hybrids outperform their parental inbred lines. Despite more than a century of intensive research across various species, the genetic basis and environmental regulation of heterosis, particularly belowground, remain poorly understood. Recent studies have suggested that the soil microbiome may influence the expression of heterosis. However, it remains unclear whether and to what extent the manifestation of heterosis shapes the associated microbiome under abiotic stress, and how these microbiomes, in turn, influence the heterotic phenotype in response to stress. In this study, we explored the potential role of rhizosheath formation in maize growth heterosis under nitrogen deprivation. Soil sterilization and inoculation experiments with bacteria of the genus Massilia demonstrated that several functional root traits contribute to the manifestation of rhizosheath-associated heterosis. Untargeted metabolomics profiling and validation with flavone-deficient mutants indicated that Massilia promote flavone secretion, which is linked to rhizosheath formation. In addition, the integration of rhizosheath transplantation experiments with soil metagenomic sequencing data confirmed that rhizosheath size determined plant growth performance under stress conditions. Taken together, these results suggest that the rhizosheath formation, which integrates root development, root exudates, and their associated microbiome, can be considered as an adaptive and heritable root trait with potential applications in modern crop breeding to combat global climate change.

INSTRUMENT(S): Liquid Chromatography MS - negative - reverse phase, Liquid Chromatography MS - positive - reverse phase

PROVIDER: MTBLS12613 | MetaboLights | 2025-09-26

REPOSITORIES: MetaboLights