Trehalose is a nonreducing disaccharide containing two glucose molecules linked through an α,α-1,1-glycosidic bond. This unique chemical structure causes trehalose levels to fluctuate significantly in plants under stress, where it functions as an osmoprotectant, enhancing plant resistance to stress. Previous studies have confirmed that the trehalose synthesis pathway is widely conserved across most plants. However, the protective role of trehalose is limited only to organelles or tissues where the concentration is sufficiently high. In this review, we summarize previous reports on improving plant stress tolerance (drought, cold, heat, salt, pathogen, etc.) by applying trehalose-6-phosphate (T6P) or trehalose and manipulating the expression of trehalose metabolism-related genes. The molecular mechanisms underlying T6P, trehalose, and their related genes that regulate plant stress resistance are reviewed. More progressive studies on the spatiotemporal control of trehalose metabolism will provide a novel tool that allows for the simultaneous enhancement of crop yield and stress tolerance. We introduce the history of trehalose and discuss the possibility of trehalose and its metabolity-related genes binding to T6P to participate in stress response through unknown signaling pathways. In addition, the effects of trehalose metabolism regulation on plant growth and stress resistance were reviewed, and the molecular mechanism was fully discussed. In particular, we came up with new insights that the molecular mechanism of trehalose metabolism to enhance plant stress resistance in the future and we propose the need to use biotechnology methods to cultivate crops with stress resistance and high yield potential.

The increase in atmospheric CO₂ concentration is a significant factor in triggering global warming. CO₂ is essential for plant photosynthesis, but excessive CO₂ can negatively impact photosynthesis and its associated physiological and biochemical processes. The tetraploid Robinia pseudoacacia L., a superior and improved variety, exhibits high tolerance to abiotic stress. In this study, we investigated the physiological and proteomic response mechanisms of the tetraploid R. pseudoacacia under high CO₂ treatment. The results of our physiological and biochemical analyses revealed that a 5% high concentration of CO₂ hindered the growth and development of the tetraploid R. pseudoacacia and caused severe damage to the leaves. Additionally, it significantly reduced photosynthetic parameters such as Pn, Gs, Tr, and Ci, as well as respiration. The levels of chlorophyll (Chl a and b) and the fluorescent parameters of chlorophyll (Fm, Fv/Fm, qP, and ETR) also significantly decreased. Conversely, the levels of ROS (H₂O₂ and O₂^·−) were significantly increased, while the activities of antioxidant enzymes (SOD, CAT, GR, and APX) were significantly decreased. Furthermore, high CO₂ induced stomatal closure by promoting the accumulation of ROS and NO in guard cells. Through a proteomic analysis, we identified a total of 1652 DAPs after high CO₂ treatment. GO functional annotation revealed that these DAPs were mainly associated with redox activity, catalytic activity, and ion binding. KEGG analysis showed an enrichment of DAPs in metabolic pathways, secondary metabolite biosynthesis, amino acid biosynthesis, and photosynthetic pathways. Overall, our study provides valuable insights into the adaptation mechanisms of the tetraploid R. pseudoacacia to high CO₂.

Canker is a destructive fungal disease that adversely affects plant growth, triggering leaf drop, branch dieback and even plant death. For the blueberry industry, fungal canker reduces blueberry yield and quality. In this study, diseased branches of the ‘Bluegold’ blueberry cultivar collected from open-field plantations in Jilin Province, China, were used to isolate and identify the pathogen, characterize its biological properties, and investigate the physiological and metabolomic responses of blueberry shoots to pathogen infection. Based on morphological characteristics and internal transcribed spacer sequence analysis, the pathogen was preliminarily identified as Diaporthe eres. Biological characterization showed that the optimal temperature and pH for mycelial growth of the isolate were 25 °C and 6, respectively, while light conditions had no significant effect on fungal growth. Pathogenicity results demonstrated that infection by the isolate significantly induced the accumulation of superoxide anions (O₂^.−) and hydrogen peroxide (H₂O₂) in blueberry new shoots, which led to lipid peroxidation and subsequently resulted in significant increases in malondialdehyde content and relative electrical conductivity. Concurrently, the plant’s antioxidant enzyme system was disrupted, and the activities of peroxidase and superoxide dismutase remained significantly elevated throughout the infection period, while catalase activity exhibited an initial increase followed by a gradual decline. Metabolomic analysis identified 541 differentially accumulated metabolites, with key metabolites including ferulic acid, quercetin and kaempferol showing marked abundance changes. These were primarily enriched in pathways closely associated with plant resistance, such as phenylpropanoid biosynthesis and flavonoid biosynthesis. Combined analysis of physiological and metabolomic data showed that reactive oxygen species accumulation and antioxidant enzyme responses were accompanied by significant enrichment of phenylpropanoid and flavonoid metabolism, indicating coordinated antioxidant regulation and secondary metabolic reprogramming in blueberry shoots following pathogen infection. Overall, this study preliminarily identified a D. eres isolate associated with blueberry canker in Jilin Province, and systematically characterized the physiological and metabolic responses of blueberry to pathogen infection, providing a theoretical basis for understanding blueberry—Diaporthe interactions and for developing effective disease management strategies.

Fragaria pentaphylla, a unique wild strawberry species in China, is rich in various fruit colors and a valuable resource for studying color genes. Fruits of different colors from F. pentaphylla were selected as the experimental material. Liquid chromatography-mass spectrometry (LC-MS) and high-throughput RNA sequencing (RNA-seq) were employed to identify key genes responsible for the development of different fruit colors. Metabolite analysis revealed that 3249 metabolites were detected, including nine differential metabolites related to anthocyanin synthesis and five biological pathways. Additionally, an analysis combining transcriptome and metabolome data showed that the structural genes FpDFR, FpCHS, FpCHI, and FpUFGT were upregulated in red fruit, with significantly higher expression levels compared to pink and white fruits, actively promoting anthocyanin production in red fruit. Conversely, genes FpANR and FpLAR were upregulated in white fruit, enhancing catechin synthesis and inhibiting anthocyanin formation. The gene FpPAL was upregulated in pink fruit. Transcription factors FpbHLH18, FpMYB1, FpMYB24, and FpMYB114 collaborate with structural genes to enhance the synthesis of anthocyanins in red fruit. The findings improve our understanding of the molecular mechanisms that control anthocyanin production in F. pentaphylla. The identified key candidate genes may be utilized in the molecular breeding of strawberries.