Soil salinization, an overwhelming problem exacerbated by climate change and anthropogenic activities, poses a significant threat to global food security by impairing plant growth, development, and crop productivity. Salinity stress induces osmotic, ionic, and oxidative stresses, disrupting physiological and biochemical processes in plants. Anthocyanins, a class of flavonoids, have emerged as key players in mitigating salt stress through their antioxidant properties, ROS scavenging, and regulation of stress-responsive pathways. During salt stress, ROS act as damaging agents and signaling molecules, upregulating anthocyanin-related genes to mitigate oxidative stress and maintain cellular homeostasis. Anthocyanins mitigate salt stress by regulating osmotic balance, ion homeostasis, and antioxidant defenses. Their biosynthesis is regulated by a network of structural and regulatory genes, including MYB, bHLH, and WD40 transcription factors, influenced by epigenetic modifications and hormonal signaling pathways such as ABA, JA, and SA. Advances in genetic engineering, including CRISPR/Cas9-mediated gene editing, have enabled the development of anthocyanin-rich transgenic plants with enhanced salt tolerance. For instance, transgenic plants overexpressing anthocyanin biosynthesis genes like DFR and ANS have demonstrated enhanced salt tolerance in crops such as tomatoes and rice. However, challenges such as variability in anthocyanin accumulation and stability under environmental stressors remain. This review highlights the translational potential of anthocyanins in crop improvement, emphasizing the need for integrated multi-omics approaches and field trials to validate their efficacy. By elucidating the molecular mechanisms of salt stress and anthocyanin-mediated stress alleviation, this work provides a foundation for developing resilient crops to address the growing challenges of soil salinization.

Among various abiotic stresses, secondary soil salinization poses a significant threat to plant productivity and survival. Cultivated chrysanthemums (Chrysanthemum morifolium), widely grown as ornamental crops, are highly susceptible to salt stress, and their complex polyploid genome complicates the identification of stress resistance genes. In contrast, C. indicum, a native diploid species with robust stress tolerance, serves as a valuable genetic resource for uncovering stress-responsive genes and improving the resilience of ornamental chrysanthemum cultivars. In this study, we cloned, overexpressed (OE-CiHY5), and silenced (RNAi-CiHY5) the CiHY5 gene in C. indicum. OE-CiHY5 plants exhibited larger leaves, sturdier stalks, and higher chlorophyll content compared to wild-type plants, while RNAi-CiHY5 plants displayed weaker growth. Under salt stress, OE-CiHY5 plants demonstrated significantly improved growth, enhanced osmotic adjustment, and effective ROS scavenging. In contrast, RNAi-CiHY5 plants were more sensitive to salinity, showing higher electrolyte leakage and impaired osmotic regulation. Transcriptomic analyses revealed that CiHY5 regulates key hormonal pathways such as zeatin (one of cytokinins), abscisic acid and jasmonic acid, as well as metabolic pathways, including photosynthesis, carbohydrate metabolism, which collectively contribute to the enhanced stress resilience of OE-CiHY5 plants. Promoter-binding assays further confirmed that CiHY5 directly interacts with the CiABF3 promoter, highlighting its critical role in ABA signaling. Evolutionary analyses showed that HY5 is conserved across plant lineages, from early algae to advanced angiosperms, with consistent responsiveness to salt and other abiotic stresses in multiple Chrysanthemum species. These findings establish CiHY5 as a key regulator of salt tolerance in C. indicum, orchestrating a complex network of hormonal and metabolic pathways to mitigate salinity-induced damage. Given the conserved nature of HY5 and its responsiveness to various stresses, HY5 gene provides valuable insights into the molecular mechanisms underlying stress adaptation and represents a promising genetic target for enhancing salt stress resilience in chrysanthemums.

Soil salinization, a prevalent form of environmental stress, leads to significant soil desertification and impacts agricultural productivity by altering the internal soil environment, slowing cellular metabolism, and modifying cellular architecture. This results in a marked reduction in both the yield and diversity of crops. Maize, which is particularly susceptible to salt stress, serves as a critical model for studying these effects, making the elucidation of its molecular responses essential for crop improvement strategies. This study focuses on the phytochrome-interacting factor 3 (PIF3), previously known for its role in freezing tolerance, to assess its function in salt stress tolerance. Utilizing two transcript variants of maize ZmPIF3 (ZmPIF3.1 and ZmPIF3.2), we engineered Arabidopsis transgenic lines to overexpress these variants and analyzed their phenotypic, physiological, biochemical, and transcriptomic responses to salt stress. Our findings reveal that these transgenic lines displayed not only enhanced salt tolerance but also improved peroxide decomposition and reduced cellular membrane damage. Transcriptome analysis indicated significant roles of hormonal and Ca2+ signaling pathways, along with key transcription factors, in mediating the enhanced salt stress response. This research underscores a novel role for ZmPIF3 in plant salt stress tolerance, offering potential avenues for breeding salt-resistant crop varieties.

Nitraria sibirica Pall is a halophytic shrub growing in desert steppe zones. It exhibits extraordinary adaptability to saline-alkali soil, drought, and sand burial. In this study, the high-affinity K+ transporter NsHKT1 was identified and found to play a key role in salt tolerance in N. sibirica. NsHKT1 was used to improve salt tolerance in a poplar hybrid. The expression characteristics of NsHKT1 were analyzed by transforming Arabidopsis and poplar with the beta-glucuronidase (GUS) gene driven by the NsHKT1 promoter. The results showed that NsHKT1 expression was induced by various abiotic stresses and phytohormones. GUS expression was also detected in the reproductive organs of transgenic Arabidopsis, indicating its function in regulating plant reproductive growth. Transgenic 84 K poplar plants overexpressing NsHKT1 exhibited less damage, higher antioxidant capacity, higher chlorophyll and proline levels, and lower malondialdehyde content compared with non-transgenic plants under salt stress. These results are consistent with the salt tolerance results for transgenic Arabidopsis overexpressing NsHKT1, indicating that NsHKT1 plays a key role in salt tolerance in herbaceous and ligneous plants. Inductively coupled plasma-optical emission spectrometry showed a significantly lower leaf Na+ content in transgenic poplar than in the non-transgenic line, revealing that NsHKT1, as a member of HKT family subclass 1, was highly selective to Na+ and prevented shoot Na+ accumulation. Transcriptome analysis indicated that differentially expressed genes in transgenic poplars under salt stress were associated mainly with the isoflavonoid, cutin, suberine, wax, anthocyanin, flavonoid, and cyanoamino biosynthesis pathways, as well as the MAPK signaling pathway, indicating that NsHKT1 not only regulates ion homeostasis but also influences secondary metabolism and signal transaction in transgenic plants.

BackgroundSalinity is one of the most damaging abiotic stress factors in agriculture, it has a negative impact on crop growth, production, and development. It is predicted that salinity will become much more severe due to global climate change. Moreover, soil salinization affects three hectares of agricultural land every minute, increasing the salinity-affected area by 10% annually. The improvement of abiotic stress tolerance in plants was made possible by recent developments involving transgenes and the isolation of some abiotic stress tolerance genes.ObjectiveThe current study aimed to synthesize, clone and characterize two abiotic stress tolerance genes Lipid transfer protein (AtLTP1) of Arabidopsis thaliana and Stress-inducible transcription factor C-repeating binding factor (LeCBF1) of Solanum lycopersicum in Saccharomyces cerevisiae.Materials and methodsThe above-mentioned genes were synthesized, cloned into the pYES2 vector then transformed into Saccharomyces cerevisiae as a model eukaryotic system. The yeast growth was measured at (OD600 nm) in a spectrophotometer, RT-PCR expression analysis and estimation of intracellular proline content after exposure to different salt concentration were performed to characterize and evaluate the physiological roles of the selected genes in the yeast.Results and conclusionThe AtLTP1 and LeCBF1 genes were cloned into the pYES2 vector for Saccharomyces cerevisiae expression. After being exposed to increasing concentrations of sodium chloride (0, 1.7, 1.8, 1.9, 2.0, 2., 2.2, and 2.3 M) for 7 days, transgenic yeast cells were tested for their ability to survive under increasing salt-stress conditions and their growth response. A spectrophotometer was used to measure yeast growth at OD600nm. The growth of the control cells was dramatically hindered when the salt content was increased to 1.9 M NaCl. However, two transgenic yeast lines continued to grow well, at a slower rate, up to 2.3 M NaCl. The two genes' expression in transgenic yeast in response to salt stress was verified by RT-PCR. In this transgenic yeast, the precise primers of LeCBF1 and AtLTP1 amplified the genes successfully at 633 base pairs and 368 base pairs, respectively. The findings showed that increasing salinization level considerably boosted the transgenic yeast's intracellular proline accumulation. It was suggested that the possibility of utilizing these genes to produce salt tolerant transgenic plants, consequently, increase the amount of land that can be exploited for agriculture.