Genetius

Using diverse Mexican maize varieties and a MAGIC population, the study demonstrated that leaf vein density is both variable and plastic, correlating positively with photosynthetic rates for small intermediate veins and increasing under heat in drought-adapted lines. Twelve QTLs linked to vein patterning were identified, highlighting candidate genes for intermediate vein development and shedding light on the evolution of high-efficiency C4 leaf architecture.

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 assessed 17 morphological, biochemical, and salt‑stress tolerance traits in 19 maize (Zea mays) landrace accessions from northern Argentina, revealing substantial variation both within and among accessions. Redundancy analysis linked phenotypic variation to the altitude of the collection sites, underscoring the potential of these landraces as sources of diverse biochemical and stress‑related traits for breeding.

The study tests whether heavy‑metal stress contributed to maize domestication by exposing teosinte (Zea mays ssp. parviglumis) and the Palomero toluqueno landrace to sublethal copper and cadmium, then analysing genetic diversity, selection signatures, and transcriptomic responses of three chromosome‑5 heavy‑metal response genes (ZmHMA1, ZmHMA7, ZmSKUs5). Results reveal strong positive selection on these genes, heavy‑metal‑induced phenotypes resembling modern maize, and up‑regulation of Tb1, supporting a role for volcanic‑derived metal stress in early maize evolution.

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 uncovers how arbuscular mycorrhizal (AM) fungi induce lateral root formation in maize by activating ethylene‑responsive transcription factors (ERFs) that regulate pericycle cell division and reshape flavonoid metabolism, lowering inhibitory flavonols. It also shows that the rhizobacterium Massilia collaborates with AM fungi, degrading flavonoids and supplying auxin, thereby creating an integrated ethylene‑flavonoid‑microbe signaling network that can be harnessed to improve nutrient uptake and crop sustainability.

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 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.

The study identifies two maize genes, Discordia3a and Discordia3b, that encode the microtubule‑severing protein KATANIN. Loss‑of‑function allele combinations reduce microtubule severing, impair cell elongation, delay mitotic entry, and disrupt preprophase band and nuclear positioning, leading to dwarfed, misshapen plants.