The study examined how altering ethylene biosynthesis (ACO1) or perception (etr1.1) in a hybrid poplar (P. tremula × P. tremuloides T89) influences the assembly of root and shoot fungal and bacterial communities, using amplicon sequencing and confocal microscopy. Ethylene modulation had limited impact on the sterile plant metabolome but triggered distinct primary and secondary metabolic changes in microbe‑colonized plants, correlating with reduced fungal colonisation of shoots and increased root fungal colonisation, while arbuscular mycorrhizal fungi and bacterial communities were largely unchanged.

The study generated a temporal physiological and metabolomic map of leaf senescence in diverse maize inbred lines differing in stay‑green phenotype, identifying 84 metabolites associated with senescence and distinct metabolic signatures between stay‑green and non‑stay‑green lines. Integration of metabolite data with genomic information uncovered 56 candidate genes, and reverse‑genetic validation in maize and Arabidopsis demonstrated conserved roles for phenylpropanoids such as naringenin chalcone and eriodictyol in regulating senescence.

The study developed a validated LC‑MS/MS method to simultaneously quantify fourteen polyamines, amino acids, and ethylene precursors in Arabidopsis thaliana and Solanum lycopersicum, and used it to compare their metabolic responses to drought, salinity, and inhibitor treatments. Distinct species‑specific metabolic adjustments were observed, with Arabidopsis showing greater fluctuations and drought generally increasing metabolite levels, while spermine exhibited stress‑specific patterns.

The study investigated whether nitrogen‑fixing rhizobial symbiosis in Medicago truncatula primes defense against the pea aphid Acyrthosiphon pisum. Metabolite profiling (LC‑MS, GC‑MS) and qPCR revealed that symbiotic plants uniquely accumulated triterpenoid saponins and up‑regulated flavonoid‑biosynthetic genes after aphid infestation, suggesting that NFS enhances pest‑specific defenses.