Aquilegia (Ranunculaceae), a genus of perennial herbs characterized by elegant leaves and unique flowers, exhibits promising application prospects in Northeast China. Chalcone synthase participates in the first enzymatic reaction of the anthocyanin biosynthesis pathway and plays a crucial role in flower color formation. In the present study, eight AoCHSs were identified and a comprehensive analysis of AoCHSs was then carried out, considering physical and chemical properties, conservative motifs, phylogenetic relationships, and cis-acting elements. The expression patterns of the AoCHSs were analyzed based on the transcriptome of A. oxysepala, which differs in sepal color between two species, to identify the candidate genes involved in flower color variation. AoCHS2/3/5 expression levels were found to be upregulated at PrA stage in A. oxysepala with dark purple sepals, while remaining consistently low in the pale-yellow species. Combining KEGG annotations and expression patterns, AoCHS5 was identified as a key gene for anthocyanin biosynthesis in Aquilegia that could play a role in the variation in flower color. The results of correlation network analysis showed that AoCHS5 was highly associated with MYB, bHLH, and WRKY. These results provided genetic resources for accelerating the molecular breeding of innovative Aquilegia flower colors.

Aquilegia oxysepala is a characteristic wildflower of Northeast China, which has great application potential owing to its unique floral morphology and strong adaptability. The R2R3-MYB is one of the largest transcription factor families and has important roles in anthocyanin biosynthesis. A total of 90 AoMYBs were identified from A. oxysepala and divided into 29 subfamilies via phylogenetic analysis. Using bioinformatics methods, a systematic analysis was conducted on the physicochemical properties, gene structures, conserved motifs, and other characteristics of these genes. Based on the transcriptomic data of A. oxysepala and A. oxysepala f. pallidiflora across different floral developmental stages, 32 differentially expressed genes (DEGs) belonging to the R2R3-MYB family were screened, and their expression patterns were analyzed. The results indicated that AoMYB32 and AoMYB34 were significantly upregulated only at the pre-anthesis stage (PrA) in A. oxysepala, whereas their expression levels remained relatively low in A. oxysepala f. pallidiflora during the same stage. Correlation network analysis indicated that AoMYB34 was positively correlated with six functional genes associated with anthocyanin synthesis, namely PAL-2, C4H, 4CL, CHS, F3′5′H, and ANS. Reverse transcription quantitative PCR (RT-qPCR) validation revealed that AoMYB32 and AoMYB34 exhibited significant upregulation at the PrA stage in A. oxysepala, while their expression showed no obvious fluctuations across the entire flowering period in A. oxysepala f. pallidiflora. In summary, it is postulated that AoMYB32 and AoMYB34 are candidate genes associated with flower color variation formation of A. oxysepala. This study provides a theoretical basis and genetic resources for deciphering the mechanism of flower color formation and facilitating flower color improvement breeding in A. oxysepala.

Salt stress severely restricts plant growth and impairs ornamental quality. The plant cell wall acts as the primary physical barrier to salt stress, and its structural integrity is critical for plant salt‑tolerance capacity. As key regulators of cell wall dynamics, pectate lyase‑like (PLL) proteins mediate cell wall remodeling via homogalacturonan depolymerization. Nevertheless, their specific functions and underlying regulatory mechanisms in salt‑stress adaptation of ornamental plants remain largely uncharacterized. In this study, we used Aquilegia oxysepala-a characteristic perennial ornamental herb native to Northeast China-to characterize the salt‑tolerance function and molecular regulatory mechanism of the salt‑inducible gene AoPLL16. AoPLL16 overexpression aggravated tobacco salt sensitivity, as evidenced by declined photosynthetic efficiency, inhibited antioxidant enzyme activities, attenuated cell wall thickness, and decreased pectin accumulation. Further functional validation verified that the upstream bHLH transcription factor AobHLH31 mediates tobacco salt tolerance by directly binding to the AoPLL16 promoter to repress its transcription. This study preliminarily identifies an AobHLH31‑AoPLL16 regulatory cascade: upon salt stress, AobHLH31 represses AoPLL16 transcription to remodel cell wall composition and structure, conferring salt tolerance to A. oxysepala.

Hosta ‘So Sweet’, a shade-tolerant Asparagaceae species, displays remarkable high-light tolerance in open-field full-sun cultivation without photoinhibition symptoms. To clarify its growing-season photosynthetic dynamics and adaptive strategies, this study measured diurnal photosynthetic variations from May to September, determined chlorophyll fluorescence parameters and pigment contents in May, July and September, and analyzed the data alongside the light and CO₂ response curves for July. The results showed that the high temperatures combined with high-light conditions in July lowered P_n relative to May and September, but the light saturation point (LSP) reached 1508.99 μmol m⁻² s⁻¹, and the CO₂ compensation point (CCP) was 75.46 μmol mol⁻¹, highlighting the robust light energy utilization and carbon assimilation potential. Meanwhile, PSII maximum photochemical efficiency (Fv/Fm) remained stable under these conditions, indicating undamaged photosystems. Mechanistically, its photosynthetic limitation strategies showed seasonal plasticity: a tight coupling between P_n, stomatal conductance, and humidity in May shifted to a strong association between P_n and photoprotective dissipation (qN) in July, followed by an optimization of light capture linked to increased chlorophyll content and adjusted Chl a/b ratios in September. Taken together, H. ‘So Sweet’ synergistically adapts to growing-season light and temperature fluctuations by integrating light utilization potential, photosystem stability and pigment adjustment strategies. This study preliminarily delineated its photosynthetic physiological profile, revealed core light-adaptive strategies, and provided a theoretical basis for the ecological application of this excellent ornamental cultivar.

Iris setosa is a characteristic perennial wild herbaceous flower in the Changbai Mountain region of China, boasting significant ornamental and medicinal values. Given the increasing scarcity of its wild resources, this study developed an efficient in vitro regeneration system using shoot tips as explants via the direct organogenesis pathway. The optimal surface sterilization protocol was achieved with a treatment of 0.1% HgCl₂ for 8 min, resulting in an explant survival rate of 57.78%. The highest multiple shoot induction rate (88.89%) of shoot tips was achieved on MS medium supplemented with 2.0 mg·L⁻¹ 6-benzylaminopurine (6-BA), 0.5 mg·L⁻¹ naphthalene acetic acid (NAA), and 1.0 mg·L⁻¹ 2,4-dichlorophenoxyacetic acid (2,4-D). The optimal shoot differentiation and proliferation medium was MS + 2.0 mg·L⁻¹ 6-BA + 0.3 mg·L⁻¹ NAA, achieving a proliferation coefficient of 3.37. The optimal medium for rooting was confirmed to be 1/2 MS + 0.5 mg·L⁻¹ indole-3-butyric acid (IBA), exhibiting a high rooting rate reached 98.33%. During transplantation, plantlets exhibited high survival rates (over 90%) and vigorous growth across all three tested substrates, with no significant differences in survival rates among substrates. The key advance of this study lies in the development of a highly efficient and stable regeneration protocol for I. setosa derived from shoot tip explants, providing critical technical backing for the conservation and sustainable exploitation of its wild-type germplasm.