Salt stress is one of the main abiotic stresses that strongly affects plant growth. Clarifying the molecular regulatory mechanism in ornamental plants under salt stress is of great significance for the ecological development of saline soil areas. Aquilegia vulgaris is a perennial with a high ornamental and commercial value. To narrow down the key responsive pathways and regulatory genes, we analyzed the transcriptome of A. vulgaris under a 200 mM NaCl treatment. A total of 5600 differentially expressed genes were identified. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis pointed out that starch and sucrose metabolism and plant hormone signal transduction were significantly improved. The above pathways played crucial roles when A. vulgaris was coping with salt stress, and their protein–protein interactions (PPIs) were predicted. This research provides new insights into the molecular regulatory mechanism, which could be the theoretical basis for screening candidate genes in Aquilegia.

Background: Elevated atmospheric CO₂ has direct and indirect influences on ecosystem processes. The impact of elevated atmospheric CO₂ concentration on carbon and nitrogen transformations, together with the microbial community, was evaluated with water hyacinth (Eichhornia crassipes) in an open-top chamber replicated wetland. The responses of nitrogen and carbon pools in water and wetland soil, and microbial community abundance were studied under ambient CO₂ and elevated CO₂ (ambient + 200 μL L⁻¹). Results: Total biomass for the whole plant under elevated CO₂ increased by an average of 8% (p = 0.022). Wetlands, with water hyacinth, showed a significant increase in total carbon and total organic carbon in water by 7% (p = 0.001) and 21% (p = 0.001), respectively, under elevated CO₂ compared to that of ambient CO₂. Increase in dissolved carbon in water correlates with the presence of wetland plants since the water hyacinth can directly exchange CO₂ from the atmosphere to water by the upper epidermis of leaves. Also, the enrichment CO₂ showed an increase in total carbon and total organic carbon concentration in wetland soil by 3% (p = 0.344) and 6% (p = 0.008), respectively. The total nitrogen content in water increased by 26% (p = 0.0001), while total nitrogen in wetland soil pool under CO₂ enrichment decreased by 9% (p = 0.011) due to increased soil microbial community abundance, extracted by phospholipid fatty acids, which was 25% larger in amount than that of the ambient treatment. Conclusion: The study revealed that the elevated CO₂ would affect the carbon and nitrogen transformations in wetland plant, water, and soil pool and increase soil microbial community abundance.

Salt stress has a considerable impact on the development and growth of plants. The soil is currently affected by salinisation, a problem that is becoming worse every year. This means that a significant amount of salt-tolerant plant material needs to be added. Aquilegia vulgaris has aesthetically pleasing leaves, unique flowers, and a remarkable tolerance to salt. In this study, RNA-seq technology was used to sequence and analyse the transcriptome of the root of Aquilegia vulgaris seedlings subjected to 200 mM NaCl treatment for 12, 24, and 48 h. In total, 12 Aquilegia vulgaris seedling root transcriptome libraries were constructed. At the three time points of salt treatment compared with the control, 3888, 1907, and 1479 differentially expressed genes (DEGs) were identified, respectively. Various families of transcription factors (TFs), mainly AP2, MYB, and bHLH, were identified and might be linked to salt tolerance. Gene Ontology (GO) analysis of DEGs revealed that the structure and composition of the cell wall and cytoskeleton may be crucial in the response to salt stress. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of the DEGs showed a significant enrichment of the pentose and glucuronate interconversion pathway, which is associated with cell wall metabolism after 24 and 48 h of salt treatment. Based on GO and KEGG analyses of DEGs, the pentose and glucuronate interconversion pathway was selected for further investigation. AP2, MYB, and bHLH were found to be correlated with the functional genes in this pathway based on a correlation network. This study provides the groundwork for understanding the key pathways and gene networks in response to salt stress, thereby providing a theoretical basis for improving salt tolerance in Aquilegia vulgaris.

Drought stress is a significant environmental factor that can impede plant growth and ornamental quality. Hemerocallis middendorffii, a drought-tolerant garden plant, has attracted attention for its ornamental value and application prospects. To investigate the molecular mechanism of drought stress resistance of H. middendorffii, this study employed 20% polyethylene glycol (PEG) 6000 to simulate drought stress. Leaves and roots of H. middendorfii were subjected to 24 h treatment and followed by transcriptome sequencing. Analysis revealed 8796 and 3401 differentially expressed genes (DEGs) in leaves and roots. The major biological processes and key molecular pathways activated under drought stress in H. middendorffii were revealed by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. The focus of this analysis was on the gene expression changes within plant hormone signal transduction pathway. Additionally, drought-associated transcription factor families such as AP2/ERF, WRKY, MYB, bHLH, NAC, and bZIP were identified among DEGs. Furthermore, potential regulatory relationships of the above transcription factors (TFs) with functional genes in the abscisic acid (ABA) and jasmonic acid (JA) signalling pathways were analysed using correlation network prediction. This research establishes the groundwork for subsequent exploration of drought-responsive gene expression and regulatory patterns in H. middendorfii and provides an importance for the systematic study of its drought-resistant molecular mechanism.

Road deicing salts are widely used during winter in northern China, which makes it essential to choose proper salt-tolerant plant species in urban landscapes. Columbine (Aquilegia) is a herb with high ornamental and commercial values. This study evaluated three Aquilegia species (A. oxysepala, A. parviflora, and A. viridiflora) for salt tolerance by monitoring their germination state under different electrical conductivity (EC) of 0.1 dS·m⁻¹ (distilled water), 1.0 dS·m⁻¹, 2.0 dS·m⁻¹, 3.0 dS·m⁻¹, 4.0 dS·m⁻¹, 5.0 dS·m⁻¹, 6.0 dS·m⁻¹, physio-biochemical responses to different EC of 0.3 dS·m⁻¹ (tap water), 5.0 dS·m⁻¹, and 10.0 dS·m⁻¹. The germination and growth parameters, visual scores, dry weight, leaf stomatal conductance, photosynthetic rate, and chlorophyll contents of three species decreased under salt stress, which was opposite to the changes of electrolyte leakage, malondialdehyde, proline, and soluble sugar contents. Superoxide dismutase and peroxidase activity trend differently among species. These results showed that the germination threshold of three species was 6.0 dS·m⁻¹. A. oxysepala was the most salt-tolerant species, with a tolerance threshold of soil conductivity in 2.83 dS·m⁻¹, followed by A. viridiflora and A. parviflora. Therefore, A. oxysepala is suitable for planting as a ground cover in urban areas where deicing salt is applied.

This study reports on extensive and in-depth investigations into the morphological, photosynthetic, and physiological indices of 10 different types of Cypripedium plant introduced from Changbai Mountain. It is an important prerequisite for the ex situ conservation of Cypripedium plants to provide new insights into their photosynthesis. This result can not only promote the production of vegetative plants but also promote the production of plants with lots of flowers and the physiological characteristics of Cypripedium plants for promoting the artificial introduction and cultivation of wild resources. A critical comparison of the results showed that high light intensity is one of the causes of the reduction in photosynthesis in the samples. Cypripedium macranthum had the most morphological advantages, while Cypripedium guttatum, the smallest plant type, had the lowest plant morphogenesis. Photoinhibition began daily at 12:00 pm and reached a second peak at 14:00 pm in all 10 types. C. macranthum, Cypripedium ventricosum, and Cypripedium calceolus had greater photosynthetic capacity than the other types. Using principal component analysis, the order of photosynthetic physiological characteristics of the 10 Cypripedium plants was CCMY > CVPP > CCRY > CMPP > CVRR > CSPY > CMWW > CMLL > CMDD > CGWW. These results lay the groundwork for future research on Cypripedium resource distribution and artificial conservation.