Genetius

The study investigated the ability of foliar-applied salicylic acid (SA) to alleviate drought stress in the high‑altitude medicinal plant Valeriana wallichii by measuring physiological and biochemical responses during vegetative and flowering stages. SA at specific concentrations improved photosynthetic rates, water‑use efficiency, chlorophyll content, membrane stability, and root biomass under both severe (25% field capacity) and moderate (50% field capacity) drought conditions. These results suggest that SA treatment enhances drought tolerance and productivity in this species.

The study examined the roles of AtKUP2, AtKUP6, AtKUP8, and GORK potassium transport proteins in guard cell function by performing gas-exchange measurements on mature Arabidopsis leaves. Loss of KUP2/6/8 reduced stomatal conductance, whereas a GORK loss‑of‑function mutant showed increased conductance, yet the magnitude of light‑ and ABA‑induced transpiration changes remained similar across genotypes, suggesting a limited dynamic range for rapid stomatal movements that relies on small ionic osmolytes.

The study demonstrates that salicylic acid (SA) restricts plant root growth through a mechanism requiring the transmembrane kinase TMK1, which leads to apoplastic alkalinization and inhibition of plasma membrane H⁺-ATPase phosphorylation. This SA effect operates independently of the auxin receptor ABP1, suggesting a novel SA-mediated pathway that balances stress responses with growth.

The study demonstrates that subfamily I ethylene receptors form the core ethylene‑sensing module and act epistatically over subfamily II receptors, uniquely possessing Ca2+‑permeable channel activity that drives ethylene‑induced cytosolic calcium influx. This reveals a mechanistic link whereby subfamily I receptors integrate hormone perception with calcium signaling in plants.

The study shows that Arabidopsis root tips adapt to hypoxia by increasing H3K4me3 levels, linked to the inhibition of group 7 demethylases (KDM7s). Genetic loss of KDM7s mimics hypoxic conditions, activating genes that sustain meristem survival, suggesting KDM7s act as root‑specific oxygen sensors that prime epigenetic tolerance mechanisms.

The study identifies wound‑induced proline transporters ProT2 and ProT3 as central regulators that link salicylic acid signaling to the suppression of de novo root regeneration (DNRR) via modulation of reactive oxygen species dynamics. Genetic loss of these transporters or pharmacological inhibition of proline transport alleviates SA‑mediated regeneration inhibition across several plant species without compromising disease resistance.

The study shows that inoculation with the non‑diazotrophic bacterium Enterobacter sp. SA187 significantly improves Arabidopsis thaliana growth under low nitrate conditions by increasing fresh weight, primary root length, and lateral root density, while enhancing nitrate accumulation and reducing shoot C:N ratios. Transcriptomic and mutant analyses reveal that these benefits depend on ethylene signaling and the activity of high‑affinity nitrate transporters NRT2.5 and NRT2.6, indicating an ethylene‑mediated, HATS‑dependent reprogramming of nitrogen uptake.

The study reveals that Arabidopsis ethylene receptors ETR1 and ERS1 function as Ca²⁺-permeable channels, with ETR1 specifically mediating ethylene‑induced cytosolic Ca²⁺ spikes that influence hypocotyl elongation. Homologous receptors from diverse land plants and algae also show Ca²⁺ permeability, and ethylene further enhances this activity, indicating a conserved regulatory role across the green lineage.

The study created transgenic Arabidopsis lines enabling inducible plasmodesmal closure via an overactive CALLOSE SYNTHASE3 allele (icals3m) and the C‑terminal domain of PDLP1, independent of pathogen signals. Induced closure triggered stress‑responsive gene expression, elevated salicylic acid levels, and enhanced resistance to Pseudomonas syringae, while also causing starch accumulation, reduced growth, and increased susceptibility to Botrytis cinerea, indicating that plasmodesmal closure itself can activate immune signaling.

The study identified twenty survival of SA-induced death (ssd) mutants that are defective in starch, glucose, nitrate metabolism, and circadian regulation, leading to excessive carbohydrate accumulation and susceptibility to salicylic acid (SA)-induced death in prolonged darkness. Glucose application rescues SA‑treated plants by antagonizing oxidative stress and restoring metabolic balance, as revealed by transcriptomic analyses that link SA‑induced cell death to effector‑triggered immunity pathways.