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.

MiR166, as an ancient and large family of plant microRNAs, has been demonstrated to participate in plant growth and development as well as responses to abi

As high soil salinity threatens the growth and development of plants, understanding the mechanism of plants’ salt tolerance is critical. The Chrysanthemum × grandiflora is a newly developed species with a strong salt resistance that possesses multiple genes controlling its quantitative salt resistance. Because of this multigene control, we chose to investigate the plant stress genes overall responses at the transcriptome level. C. grandiflora were treated with a 200 mM NaCl solution for 12 h to study its effect on the roots and leaves via Illumina RNA sequencing. PAL, CYP73A, and 4CL in the phenylpropanoid biosynthesis pathway were upregulated in roots and leaves. In the salicylic acid signal transduction pathway, TGA7 was upregulated in the roots and leaves, while in the jasmonic acid signal transduction pathway, TIFY9 was upregulated in the roots and leaves. In the ion transporter gene, we identified HKT1 that showed identical expression patterns in the roots and leaves. The impact of NaCl imposition for 12 h was largely due to osmotic effect of salinity on C. grandiflora, and most likely the transcript abundance changes in this study were due to the osmotic effect. In order to verify the accuracy of the Illumina sequencing data, we selected 16 DEGs for transcription polymerase chain reaction (qRT-PCR) analysis. qRT-PCR and transcriptome sequencing analysis revealed that the transcriptome sequencing results were reliable.

Ornamental plant species may vary substantially in their tolerance response to heavy metals. The aim of this research was to check chrysanthemum cultivars, namely Donglin Ruixue (C), Yellow (F), Red pocket (G), and New 9714 (I), which are commonly used as landscape plants to determine their levels of cadmium (Cd) tolerance at different cadmium concentrations through hydroponic cultures. Chrysanthemum cultivars were treated with five different Cd concentrations (0, 10, 20, 50, and 100 mg L⁻¹) and different physiological, enzymatic, and ultra-structure traits were taken under consideration in vitro. The results showed that cadmium concentration significantly inhibited the total chlorophyll content, chlorophyll a, chlorophyll b, and carotenoid content. Chlorophyll contents were significantly reduced at higher Cd concentrations in all cultivars, but the reduction rates were higher in cultivar F (59.49%), G (40.41%), I (44.97%), and C (33.86%). Similarly, the chlorophyll b reduction was higher than that of chlorophyll a in I (73.33%), followed by G (58.06%), F (61.66%), and C (32.43%), under Cd stress conditions. Additionally, the relative conductivity was recorded in cultivars C (146.48%), F (223.66%), G (165.96%), and I (154.92%), respectively, at 100 mg L⁻¹ Cd concentrations. Likewise, MDA was significantly increased with high Cd stress, at 155.56, 325.27, 173.91, and 322.18%, in C, F, G, and I cultivars at 100 mg L⁻¹, but it was promoted with a greater increase in F and I cultivars. Similarly, SOD and CAT activities were increased with the increase in Cd stress, but reduced in F and I cultivars at higher stress levels of 100 mg L⁻¹. In the same way, POD activity was significantly higher in the C and G cultivars. Additionally, ultrastructure changes also occurred with the increase in the Cd stress, i.e., 20 mg L⁻¹ to 100 mg L⁻¹, and these changes caused alterations in cell organelles, including in the chloroplast, grana, lamella, thylakoid, and stroma. They also caused noticeable damage to mitochondria at higher Cd concentrations. It was concluded that the higher levels of antioxidative defense of the C and G cultivars of chrysanthemum indicated their ability to tolerate high Cd stress conditions. These could, therefore, be used for their phytoremediation potential in Cd-contaminated areas.

Abiotic stresses, such as salt and drought, significantly affect plant development and are the major limiting factors for crop quality and productivity. The manipulation of genes involved in plant stress response facilitates plant mitigation of adverse environments. In this study, we characterized CgbZIP1, a differentially expressed gene under normal and salinity conditions in Chrysanthemum grandiflora. CgbZIP1 was significantly upregulated by salt stress and also strongly responsive to drought stress and ABA treatments. Bioinformatics and subcellular localization analyses revealed that CgbZIP1 is a bZIP transcription factor and localized to the nucleus. Transgenic tobacco plants overexpressing CgbZIP1 exhibited significantly enhanced salt and drought stress tolerance associated with characteristic morphological and physiological indexes. The results demonstrate the important role CgbZIP1 plays in plant stress response and suggest its potential use in other crops for improved stress resistance.

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.