The study demonstrates that LysM receptor-like kinases are essential for establishing ectomycorrhizal symbiosis in poplar, as CRISPR/Cas9 knockouts of three NFP-like genes abolish recognition of Laccaria bicolor signals, calcium spiking, symbiotic gene expression, and typical root phenotypes. This provides the first evidence linking LysM receptors to ectomycorrhizal interactions in a woody host.

The study identifies and functionally characterizes an acetyl‑CoA:monolignol transferase gene in Populus, showing that its overexpression elevates acetate incorporation into lignin without harming plant growth. Elevated lignin acetylation correlates with gene expression levels and markedly improves biomass pretreatability for biofuel production.

The study examined electrophysiological responses of young poplar trees to controlled stem bending and root pressurization, identifying a distinct gradual potential (GP) whose amplitude and propagation are modulated by stimulus speed and intensity. Results indicate that mechanical stress generates a transient hydraulic pressure wave that triggers the GP, suggesting a hydraulic‑electrical coupling mechanism that encodes detailed mechanical information for adaptive responses to wind.

Populus VariantDB v3.2 is a searchable database that catalogs sequence polymorphisms across heterozygous poplar genomes, enabling precise design of guide RNAs and primers for CRISPR genome editing in outcrossing tree species. The tool accepts short sequence inputs, supports multiple Populus genomes (including hybrids), and provides customizable search parameters to improve gRNA/primer design accuracy. Its platform‑agnostic and expandable architecture makes it broadly applicable to sequence‑sensitive functional genomics studies.

The study used comparative and de‑novo transcriptomic analyses in poplar to uncover plant and fungal gene regulons that govern ectomycorrhizal (ECM) compatibility, distinguishing general fungal‑sensing responses from ECM‑specific pathways. Key findings include modulation of jasmonic acid‑related defenses, coordinated regulation of secretory and cell‑wall remodeling genes, and dynamic expression of the Common Symbiosis Pathway during early and mature symbiosis stages.