Diurnal Rhythmicity in the Rhizosphere Microbiome-Mechanistic Insights and Significance for Rhizosphere Function.

The rhizosphere is a key interface between plants, microbes and the soil which influences plant health and nutrition and modulates terrestrial biogeochemical cycling. Recent research has shown that the rhizosphere environment is far more dynamic than previously recognised, with evidence emerging for diurnal rhythmicity in rhizosphere chemistry and microbial community composition. This rhythmicity is in part linked to the host plant's circadian rhythm, although some heterotrophic rhizosphere bacteria and fungi may also possess intrinsic rhythmicity.

Circadian rhythms in the plant host influence rhythmicity of rhizosphere microbiota.

Background: Recent studies demonstrated that microbiota inhabiting the plant rhizosphere exhibit diel changes in abundance. To investigate the impact of plant circadian rhythms on bacterial and fungal rhythms in the rhizosphere, we analysed temporal changes in fungal and bacterial communities in the rhizosphere of Arabidopsis plants overexpressing or lacking function of the circadian clock gene LATE ELONGATED HYPOCOTYL (LHY).

Results: Under diel light-dark cycles, the knock-out mutant lhy-11 and the gain-of-function mutant lhy-ox both exhibited gene expression rhythms with altered timing and amplitude compared to wild-type plants.

Comparative Genomics across Three Ensifer Species Using a New Complete Genome Sequence of the Medicago Symbiont () WSM1022.

Here, we report an improved and complete genome sequence of () strain WSM1022, a microsymbiont of , revealing its tripartite structure. This improved genome sequence was generated combining Illumina and Oxford nanopore sequencing technologies to better understand the symbiotic properties of the bacterium. The 6.

Plant circadian clock control of Medicago truncatula nodulation via regulation of nodule cysteine-rich peptides.

Legumes house nitrogen-fixing endosymbiotic rhizobia in specialized polyploid cells within root nodules, which undergo tightly regulated metabolic activity. By carrying out expression analysis of transcripts over time in Medicago truncatula nodules, we found that the circadian clock enables coordinated control of metabolic and regulatory processes linked to nitrogen fixation. This involves the circadian clock-associated transcription factor LATE ELONGATED HYPOCOTYL (LHY), with lhy mutants being affected in nodulation.