Phosphorus deficiency poses a significant challenge to plant growth and development, particularly in red soil. To alleviate this limitation, phosphorus-solubilizing bacteria (PSB) play a crucial role by converting insoluble phosphates present in the soil into soluble forms that are accessible to plants. Cornus wilsoniana Wangerin is a representative oil crop cultivated in red soil, holding a prominent position within China’s forestry economic system. Consequently, it is essential to develop highly stable microbial phosphorus enhancement strategies to manage agricultural phosphorus in red soil regions, thereby maintaining the available phosphorus content necessary for the production of C. wilsoniana. In this study, the application of Streptomyces misionensis SwB1 bacterial suspension to the rhizosphere of C. wilsoniana significantly increased the content of various phosphorus fractions (H₂O-P, NaHCO₃-P, NaOH-P, HCl-P) in red soil, with NaHCO₃-P content increasing by 4.97 times and NaOH-P content by 3.87 times. Additionally, the genome of S. misionensis SwB1 contains 25 phosphorus-solubilizing genes, 13 nitrogen-fixing genes, 17 siderophore production genes, and 11 indole-3-acetic acid (IAA) production genes, indicating its potential for enhancing nutrient availability. Comparative genomic analysis of 15 strains belonging to five species of Streptomyces revealed that S. misionensis SwB1 possesses an extensive genetic repertoire and complete gene clusters associated with phosphorus solubilization. Furthermore, five phosphorus solubilization pathways of S. misionensis SwB1 were summarized: the Pst system, Pit system, siderophore transport, phosphatase synthesis, and organic acid synthesis. Ultimately, the inoculation of S. misionensis SwB1 significantly enhanced the growth and biomass accumulation of C. wilsoniana at the seedling stage, evidenced by an increase in fresh weight by 81.44%, a rise in net photosynthetic rate by 18.51%, and a surge in the number of root tips by 36.24%. Taken together, our findings support a sophisticated multi-pathway bacteria phosphorus solubilization approach and identified a highly efficient phosphorus-solubilizing strain, S. misionensis SwB1, which has the potential to become a microbial fertilizer.

Swida wilsoniana is an important oil-producing tree species whose fruits are rich in unsaturated fatty acids with high nutritional and medicinal value. Lipases are involved not only in lipid mobilization but also potentially in the regulation of fatty acid composition and oil accumulation in plants. In this study, the fatty acid composition of S. wilsoniana fruits was analyzed using gas chromatography–flame ionization detection (GC-FID), and the three most abundant fatty acids were selected as molecular docking ligands. Based on overall multi-ligand docking performance (including mean affinity across the three ligands), three key lipases—SwL5, SwL8, and SwL12—were identified as having the strongest interactions with these fatty acids. Phylogenetic analysis revealed that SwL5 and SwL12 belong to lipase family II, while SwL8 is classified into family VI. Molecular dynamics simulations were further performed to evaluate the binding stability and to characterize the structural basis of substrate recognition, including key interacting residues. This study provides theoretical insights into the molecular regulation of fatty acid composition in S. wilsoniana, and offers potential gene targets for the genetic improvement of oil quality traits.

The oleic-to-linoleic acid ratio (O/L) is a key determinant of oil quality, yet its molecular basis in Cornus wilsoniana remains unclear. Here, we combined fatty-acid profiling with molecular dynamics (MD) simulations and catalytic tunnel analysis to compare four annotated FAD2 homologs. Sequence alignment revealed a major variable segment at residues 160–185, including a small deletion in CW09G04700 and an extensive deletion in CW04G07690. Docking against oleic acid supported excluding CW04G07690 due to weak binding. Eighty-nanosecond MD simulations showed that CW02G01750 and CW09G27260 rapidly converged to stable conformational ensembles with lower core flexibility, whereas CW09G04700 exhibited higher internal mobility around residues 180–220. CAVER analysis further indicated increasingly accessible catalytic tunnels for CW02G01750 and CW09G27260 during simulation, while CW09G04700 displayed transient tunnel narrowing accompanied by ligand conformational readjustments. These results nominate CW02G01750 as a leading structural candidate among C. wilsoniana FAD2 homologs and highlight access-pathway dynamics as a mechanistic feature potentially contributing to O/L formation.