Coconut holds significant importance as a fruit and oilseed crop in tropical and subtropical regions. However, low-temperature (LT) stress has caused substantial reductions in yield and economics and impedes coconut production, therefore constraining its widespread cultivation and utilization. The appropriate application of potassium (K) has the potential to enhance the cold tolerance of crops and mitigate cold damage, but the regulatory mechanisms by which K improves coconut adaptability to cold stress remain poorly understood. Transcriptome and metabolomic analyses were performed on coconut seedlings treated with LT (5 °C) and room temperature (25 °C) under various K conditions: K₀ (0.1 mM KCL), K_L (2 mM KCL), K_M (4 mM KCL), and K_H (8 mM KCL). Correlation analysis with physiological indicators was also conducted. The findings indicated that K absorption, nutrient or osmotic regulation, accumulation of substances, photosynthesis, hormone metabolism, and reactive oxygen species (ROS) clearance pathways played crucial roles in the adaptation of coconut seedlings to LT stress. LT stress disrupted the homeostasis of hormones, antioxidant enzyme activity, chlorophyll, K, and the regulation of nutrients and osmolytes. This stress also leads to the downregulation of genes and metabolites related to K transporters, hormone metabolism, transcription factors, and the metabolism of nutrients and osmolytes. Applying K helped maintain the homeostasis of hormones, antioxidant enzyme activity, chlorophyll, K, and the regulation of nutrients and osmolytes, promoted the removal of ROS, and reduced malondialdehyde, consequently diminishing the damage caused by LT stress to coconut seedlings. Furthermore, the comprehensive analysis of metabolomics and transcriptomics highlighted the importance of carbohydrate metabolism, biosynthesis of other secondary metabolites, amino acid metabolism, lipid metabolism, and ABC transporters in K’s role in improving coconut seedlings’ tolerance to LT stress. This study identified the pivotal biological pathways, regulatory genes, and metabolites implicated in K regulation of coconut seedlings to acclimate to LT stress.

Skunk cabbage (Symplocarpus renifolius) blooms in early spring and its inflorescence, referred to as the spadix, can produce enough heat to melt snow. Here, we investigated glycolytic carbon flow at the PEP branch-point in thermogenic spadices. Our analyses revealed that petals and pistils in thermogenic florets exhibited higher expression of SrPEPC and SrAOX transcripts than those of SrPK, SrPEPCK, and SrPEPtase. Moreover, enzymatic analyses showed high activities of PEPC in the extracts from thermogenic florets. Finally, mitochondria from thermogenic florets showed low respiratory activities when pyruvate was used as a substrate, although a significant malate-mediated cyanide-insensitive respiration was observed. Collectively, these results suggest that PEP metabolism, primarily catabolized by PEPC, plays a critical role in thermogenesis in S. renifolius.

Salinity is one of the key threats to food security and sustainability. To make saline soils productive again, we need to develop salt-tolerant crop varieties. Developing salt-tolerant wheat requires a detailed understanding of the molecular mechanisms underlying salt stress responses. In this study, we analyzed the Chinese Spring genome and identified 559 putative NAC transcription factors (TFs), which are recognized as key regulators of both abiotic and biotic stress. Protein family analysis revealed four distinct domain architectures, with more than 95% of the proteins containing a single NAC domain, consistent with their conserved regulatory role. Through in silico analyses, four salt stress-responsive TFs, NAC_1D, NAC_2D, NAC_4A, and NAC_5A, were highlighted, sharing nine of 13 DNA-binding residues. Promoter analysis of their putative target genes identified seven candidates, which, together with the NAC TFs, were subjected to RT-qPCR expression analysis in BARI Gom-25 plants exposed to 100 mM NaCl. The expression data revealed contrasting regulatory patterns between NAC TFs and their target genes. For example, Hsp70 was strongly upregulated in both shoots and roots, despite opposite patterns of NAC_1D expression between tissues. Similarly, bZIP expression mirrored the downregulation of NAC_2D, whereas HKT8 expression remained stable under salt stress. NAC_4A showed a root-specific pattern suggestive of positive regulation of a Non-specific serine/threonine protein kinase, while NAC_5A upregulation corresponded with downregulation of Plant cadmium resistance 2. Collectively, these results provide functional insights into four NAC TFs and identify potential molecular targets for improving wheat salt tolerance. By targeting key tolerance genes at the DNA level offers greater precision and can significantly reduce breeding time.

Lead (Pb) pollution is a severe environmental condition that inhibits the growth of plants by causing oxidative stress and interference with cellular and molecular functions. Genotypic variation in stress tolerance has been identified in wheat varieties (Triticum aestivum L.), but there has been limited evidence of integrated physiological, biochemical, and transcriptomic responses to Pb. Pb exposure (0-3 mM lead acetate) had significant effect on shoot height and root length in all wheat varieties with root being more sensitive than shoot. The BARI Gom 30 genotype variety showed a relatively higher tolerance with BARI Gom 25 being the most sensitive. The markers of oxidative stress (H₂O₂ and MDA) were increased in a dose-dependent manner, which indicates enhanced cellular damage under Pb stress. The initial increase in antioxidant enzymes (CAT, POD, and APX) occurred at moderate intensity and declined at high concentrations, indicating that defense capacity is broken down at high levels of stress. Transcriptomic analysis of wheat root tissues (GEO accession: GSE235844) identified differentially expressed genes that were related to regulation of oxidative stress, ion transport, protein degradation, and transcriptional control. These molecular responses were correlated with observed physiological and biochemical alterations, which indicate well-coordinated mechanisms of stress-responses. Dataset integration revealed the important pathways that are involved in redox balance and stress adaptation. The physiological, biochemical, and molecular responses involved in Pb toxicity in wheat are interconnected with each other. Genotypic differences in tolerance highlight the importance of genetic factors in stress adaptation. This integrative analysis provides mechanistic insights into Pb stress responses and supports future breeding of heavy metal-tolerant wheat varieties.