Search Results (557)

Kiwifruit (Actinidia spp.) is a globally important economic fruit with high nutritional value. Fruit peelability, defined as the mechanical ease of separating the peel from the fruit flesh, is a critical quality trait influencing consumer experience and market competitiveness and has emerged as a critical breeding target in fruit crop improvement programs. The present review systematically synthesized existing studies on kiwifruit peelability, and focused on its evolutionary trajectory, genotypic divergence, quantitative evaluation, possible underlying mechanisms, and artificial manipulation strategies. Kiwifruit peelability research has advanced from early exploratory studies in New Zealand (2010s) to systematic investigations in China (2020s), with milestones including the development of evaluation metrics and the identification of genetic resources. Genotypic variation exists among kiwifruit genera. Several Actinidia eriantha accessions and the novel Actinidia longicarpa cultivar ‘Guifei’ exhibit superior peelability, whereas most commercial Actinidia chinensis and Actinidia deliciosa cultivars exhibit poor peelability. Quantitative evaluation highlights the need for standardized metrics, with “skin-flesh adhesion force” and “peel toughness” proposed as robust, instrument-quantifiable indicators to minimize operational variability. Mechanistically, peelability is speculated to be governed by cell wall polysaccharide metabolism and phytohormone signaling networks. Pectin degradation and differential distribution during fruit development form critical “peeling zones”, whereas ethylene, abscisic acid, and indoleacetic acid may regulate cell wall remodeling and softening, collectively influencing skin-flesh adhesion. Owing to the scarcity of easy-to-peel kiwifruit cultivars, artificial manipulation methods, including manual peeling benchmarking, lye treatment, and thermal peeling, can be employed to further optimize kiwifruit peelability. Currently, shortcomings include incomplete genotype-phenotype characterization, limited availability of easy-peeling germplasms, and a fragmented understanding of the underlying mechanisms. Future research should focus on methodological innovation, germplasm development, and the elucidation of relevant mechanisms. Full article

Gibberellins (GAs) are essential phytohormones that regulate seed dormancy release and germination. Lomatogonium rotatum (L.) Fries ex Nym is a traditional medicinal plant whose seed germination is often hindered by physiological dormancy. In this study, we systematically investigated the effects of exogenous GA₃ on the seed germination of L. rotatum and elucidated the underlying molecular regulatory mechanisms via transcriptomic analysis. GA₃ treatment (500 mg/L for 24 h) significantly improved the germination rate, vigor index, and other germination traits. RNA-seq analysis identified time-dependent transcriptional changes in GA₃-treated seeds across three developmental stages (24 h, 72 h, and 96 h). KEGG enrichment and K-means clustering revealed dynamic actiSvation of hormonal signaling, secondary metabolism, and DNA replication pathways. WGCNA uncovered two hormone-responsive co-expression modules (Red and Lightcyan) corresponding to early and late stages of germination, respectively. Key genes related to ABA and GA biosynthesis and signal transduction showed phase-specific expression, highlighting the coordinated hormonal regulation during seed germination. Our findings provide new insights into the molecular basis of GA₃-regulated seed germination and offer theoretical support for the cultivation and utilization of L. rotatum. Full article

Light quality and duration profoundly influence the growth and productivity of plant species. This study investigated the effects of a blue–red LED light combination, known to induce flowering, on the physiological state and content of biologically active substances in catmint (Nepeta nuda L.) grown under controlled in vitro conditions. White light (W) was used as a control and compared with two blue–red intensities: BR (high-intensity blue–red light) and BRS (low-intensity blue–red light or “BR with shadow”). BR-treated plants showed increased leaf area, mesophyll thickness, biomass and starch content but reduced levels of plastid pigments. BR also modified the oxidative state of plants by inducing lipid peroxidation while simultaneously activating ROS scavenging mechanisms and enhancing phenolic antioxidants. Interestingly, BR decreased the accumulation of the Nepeta sp.-specific iridoid, nepetalactone. These effects appear to be regulated by the phytohormones auxin, abscisic acid and jasmonates. BRS treatment produced effects similar to the W control but led to increased plant height and reduced leaf area and thickness. Both BR and BRS regimes induced the accumulation of proteins and amino acids. We conclude that blue–red light can enhance the survival capacity of micropropagated N. nuda during subsequent soil adaptation, suggesting that similar light pre-treatment could improve plant performance under stress conditions. Full article

UDP-glycosyltransferases (UGTs) play essential roles in various biological processes, such as phytohormone homeostasis, abiotic stress adaptation, and secondary metabolite biosynthesis. Populus euphratica is a model species for investigating stress adaptation; however, the PeUGT gene family has yet to be systematically characterized. Here, we identified 134 UGT genes in P. euphratica. Phylogenetic analysis classified these genes into 16 major groups (A–P), and UGT genes within the same groups showed similar structural characteristics. Tandem duplication events were identified as the predominant mechanism driving the expansion of the PeUGT family. Cis-acting element analysis revealed an enrichment of motifs associated with developmental regulation, light response, phytohormone signaling, and abiotic stress in the promoters of PeUGT genes. Expression profiling demonstrated spatiotemporal regulation of the PeUGT genes under drought stress. Among them, PeUGT110 was significantly induced by PEG treatment in the leaf, root, and stem tissues of P. euphratica. Overexpression of PeUGT110 enhanced drought tolerance in transgenic Arabidopsis. Furthermore, the PeUGT110-OE lines exhibited reduced malonaldehyde accumulation, elevated proline content, higher superoxide dismutase activity, and upregulated expression of stress-related genes under drought stress. The results demonstrated that PeUGT110 plays a critical role in plant drought resistance. These findings establish a foundation for elucidating the function of PeUGT genes. Full article

Anthocyanins are important phenolic compounds in grape skins, affecting the color, oxidation resistance, and aging ability of red wine. In recent years, global warming has had a negative effect on anthocyanin biosynthesis in grape berries. Ethylene serves as a crucial phytohormone regulating the development and ripening processes of fruit; however, the specific molecular mechanism and the regulatory network between ethylene signaling and the anthocyanin biosynthesis pathway remain incompletely understood. In this study, 400 mg/L ethephon (ETH) solution was sprayed onto the surface of grape berries at the lag phase (EL-34), and the changes in anthocyanin-related genes and metabolites were explored through transcriptomic and metabolomic analysis. The results showed that ETH treatment increased Brix and pH in mature berries. In total, 35 individual anthocyanins were detected, in which 21 individual anthocyanins were enhanced by ETH treatment. However, the anthocyanin profile was not affected by exogenous ethylene. Transcriptomics analysis showed that there were a total of 825 and 1399 differentially expressed genes (DEGs) 12 h and 24 h after treatment. Moreover, key structural genes in the anthocyanin synthesis pathway were strongly induced, including VvPAL, VvCHS, VvF3H, VvF3′5′H, VvDFR and VvUFGT. At the maturity stage (EL-38), the expression levels of these genes were still higher in EHT-treated berries than in the control. ETH treatment also influenced the expression of genes related to hormone biosynthesis and signal transduction. The ethylene biosynthesis gene (VvACO), ethylene receptor genes (VvETR2, VvERS1 and VvEIN4), ABA biosynthesis gene (VvNCED2), and ABA receptor gene (VvPYL4) were up-regulated by ETH treatment, while the auxin biosynthesis gene (VvTAA3) and seven genes of the auxin-responsive protein were inhibited by exogenous ethylene. Meanwhile, ETH treatment promoted the expression of the sugar transporter gene (VvEDL16) and two sucrose synthase genes (VvSUS2 and VvSUS6). In EHT-treated berries, 19 MYB and 23 ERF genes were expressed differently compared with the control (p < 0.05). This study provides the theoretical foundation and technical support for the regulation of anthocyanin synthesis in non-climacteric fruit. Full article

Numerous scientific studies have confirmed the effectiveness of seed bioactivation using electromagnetic fields (EMFs) in agriculture. This article presents the results of the remote application of an EMF TOR device in the cultivation of barley Hordeum vulgare L. Laboratory studies and field tests were conducted, showing a positive effect on the growth and development of plants both when treating dry seeds before sowing and when treating sown seeds in the field. The optimal time period for EMF treatment was determined: treating air-dried seeds with EMFs before sowing for 10–15 min increased germination by 5–18% and the growth rate of seedlings by 2–3 times. The maximum observed effect occurred during the treatment period from 7:00 to 11:00. As a result of changing the balance of phytohormones, the further stimulation of the root system and the assimilation surface of plants was noted due to a 1.5-fold increase in the content of auxins. The density of productive stems, ear length, seed set, and 1000 seed weight increased, which ultimately led to an increase in yield by more than 10% and, in some varieties, to a decrease in the protein content in grains compared to the control variant (by 3–22%), bringing them closer to brewing conditions. Full article

Low temperature is a major abiotic stress affecting rice productivity. Selenium (Se) treatment has been shown to enhance plant resilience to cold stress. In this study, low concentrations of selenium (ColdSe1) alleviated the adverse effects of cold stress on rice seedlings, improving fresh weight, plant height, and chlorophyll content by 36.9%, 24.3%, and 8.4%, respectively, while reducing malondialdehyde (MDA) content by 29.1%. Se treatment also increased the activities of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), by 25.2%, 42.7%, and 33.3%, respectively, and upregulated flavonoids, soluble sugars, cysteine (Cys), glutathione (GSH), and oxidized glutathione (GSSG). Transcriptome analysis revealed that ColdSe1 treatment upregulated genes associated with amino and nucleotide sugar metabolism, glutathione metabolism, and fructose and mannose metabolism. It also alleviated cold stress by modulating the MAPK signaling pathway, phytohormone signaling, and photosynthesis-related pathways, enriching genes and transcription factors linked to antioxidant metabolism and photosynthesis. Metabolomic analyses showed that ColdSe1 positively influenced amino acid glucose metabolism, glycerolipid metabolism, hormonal pathways, and alanine/glutamate pathways under cold stress, while also upregulating metabolites associated with plant secondary metabolites (e.g., flavonoids, phenolic compounds) and antioxidant metabolism (e.g., α-linolenic acid metabolism). In contrast, high selenium concentrations (ColdSe2) disrupted phenylpropanoid biosynthesis, α-linolenic acid metabolism, and ABC transporter function, exacerbating cold-stress injury. This study highlights the critical role of Se in mitigating cold stress in rice, offering a theoretical basis for its application as an agricultural stress reliever. Full article

The global expansion of soil salinization has intensified the need to understand plants’ salt tolerance mechanisms. This study investigates the molecular basis of salt stress responses in Melia azedarach L. and the modulating role of 24-epibrassinolide (EBR) through transcriptomic analysis. While salt stress significantly inhibited seedling growth, EBR application substantially mitigated these effects. Transcriptomic analysis identified 11,747 differentially expressed genes (DEGs) in the salt-treated versus control seedlings (SA vs. CK) comparison, 3786 DEGs in the Salt + EBR-treated versus control seedlings (E1 vs. CK) comparison, and 8019 DEGs in the Salt + EBR-treated versus salt-treated seedlings (E1 vs. SA) comparison. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified the pivotal pathways in salt stress adaptation, such as plant hormone signal transduction, phenylpropanoid biosynthesis, and ribosome pathways. Notably, key regulators such as AUX1, TIR1, IAA, SAUR, PYL, and ABF showed dynamic expression patterns under salt stress and EBR treatment, revealing their critical roles in stress mitigation. Our findings provide novel insights into EBR-mediated salt tolerance, highlighting its potential to modulate phytohormone signaling networks. This study advances both the fundamental knowledge of salt stress adaptation and practical strategies for enhancing plant resilience in saline environments. Full article

The hard-seed coat of Ormosia henryi significantly impedes germination efficiency in massive propagation, while conventional physical dormancy-breaking methods often result in compromised seed vigor, asynchronous seedling emergence, and diminished stress tolerance. Seed biopriming, an innovative technique involving the inoculation of beneficial microorganisms onto seed surfaces or into germination substrates, enhances germination kinetics and emergence uniformity through microbial metabolic functions and synergistic interactions with seed exudates. Notably, spermosphere-derived functional bacteria isolated from native spermosphere soil demonstrate superior colonization capacity and sustained bioactivity. This investigation employed selective inoculation of these indigenous functional strains to systematically analyze dynamic changes in endogenous phytohormones, enzymatic activities, and storage substances during critical germination phases, thereby elucidating the physiological mechanisms underlying biopriming-enhanced germination. The experimental results demonstrated significant improvements in germination parameters through biopriming. Inoculation with the Bacillus sp. strain achieved a peak germination rate (76.19%), representing a 16.19% increase over the control (p < 0.05). The biopriming treatment effectively improved the seed vigor, broke the impermeability of the seed coat, accelerated the germination speed, and positively regulated physiological indicators, especially amylase activity and the ratio of gibberellic acid to abscisic acid. This study establishes a theoretical framework for microbial chemotaxis and rhizocompetence in seed priming applications while providing an eco-technological solution for overcoming germination constraints in O. henryi cultivation. The optimized biopriming protocol addresses both low germination rates and post-germination growth limitations, providing technical support for the seedling cultivation of O. henryi. Full article

Background: N6-methyladenosine (m6A) is the most prevalent chemical modification of eukaryotic RNA, playing a crucial role in regulating plant growth and development, stress responses, and other essential biological processes. The enzymes involved in m6A modification—methyltransferases (writers), demethylases (erasers), and recognition proteins (readers)—have been identified in various plant species; however, their roles in the economically significant tree species Populus deltoides × P. euramericana (NL895) remain underexplored. Results: In this study, we identified 39 m6A-related genes in the NL895 genome, comprising 8 writers, 13 erasers, and 18 readers. Evolutionary analysis indicated that the expansion of writers and readers primarily resulted from whole-genome duplication events. Purifying selection pressures were observed on all duplicated gene pairs, suggesting their essential roles in functional differentiation. Phylogenetic analysis revealed that writers, erasers, and readers are categorized into six, four, and two groups, respectively, with these genes being more conserved among dicotyledonous plants. Gene structure, protein domains, and motifs exhibited greater conservation within the same group. Promoter analysis of m6A-related genes showed enrichment of cis-acting elements associated with responses to light, phytohormones, and stress, indicating their potential involvement in gene expression regulation. Under cadmium treatment, the expression of all writers was significantly upregulated in both the aboveground and root tissues of NL895. Conclusions: This study systematically identified m6A-related gene families in Populus deltoides × P. euramericana (NL895), elucidating their evolutionary patterns and expression regulation characteristics. These findings provide a theoretical foundation for analyzing the molecular mechanisms of m6A modification in poplar growth, development, and stress adaptation, and offered candidate genes for molecular breeding in forest trees. Full article

As key endogenous signal molecules regulating plant growth processes, plant hormones have significant applications in forage breeding. The experiment used ‘Elymus sibiricus Qingmu No. 2’ as the test material, and the effects of foliar applied phytohormones of gibberellin (GA₃: 50, 100, 200, and 300 mg/L), cytokinin (6-BA: 1, 10, 100, and 150 mg/L), epibrassinolide (EBR: 0.01, 0.1, 1, and 10 mg/L), zeatin (ZT: 1, 10, 20, and 100 mg/L), and auxin (IAA: 10, 50, 100, and 150 mg/L) on growth and physiological responses in Elymus sibiricus were investigated. The results indicated that GA₃ at 200 mg/L significantly enhanced biomass by 38.19%, plant height by 75.11%, and leaf area by 40.58% compared to controls. IAA (150 mg/L) specifically increased stem diameter by 38.25%, while 6-BA (100 mg/L) elevated chlorophyll content and antioxidant enzyme activities, indicating dual photoprotective and stress-mitigating roles. EBR (1 mg/L) and ZT (20 mg/L) moderately enhanced growth metrics. All treatments universally boosted stress tolerance via soluble sugar/protein accumulation and antioxidant system activation. Through comprehensive analysis, we recommend GA₃ (200 mg/L) for effective grassland improvement, propose synergistic combinations of 6-BA and IAA to overcome morphological limitations, and highlight ultra-low EBR (0.01–0.1 mg/L) as a priority for future research. Full article

The SHORT INTERNODES-related sequence (SRS) gene family, comprising zinc finger and IXGH domain-containing transcription factors, serves as a critical regulator of plant biological processes and abiotic stress responses. In this study, the common wheat cultivar Chinese Spring was selected as the experimental material. Comprehensive bioinformatic analysis was performed using ClustalX, MEGA, MEME, and PlantTFDB v5.0 to systematically characterize SRS family members within the wheat genome. The systematic examination of physicochemical properties, conserved domains, phylogenetic relationships, gene structures, and cis-acting elements was conducted, providing insights into the functional roles of this gene family in wheat growth and development. Fifteen SRS family members containing conserved zinc finger and IXGH domains were identified. Distinct expression patterns were observed among TaSRS subgroups: Members of Groups I, III, and V exhibited significantly higher transcript levels in roots, stems, leaves, and anthers compared to other subgroups. Notably, the majority of TaSRS genes, including representatives from Groups I, III, IV, and V, displayed responsiveness to NaCl and ABA stress treatments, suggesting their putative involvement in both salinity adaptation and phytohormone-mediated stress signaling. Differential expression patterns of TaSRS genes under NaCl and ABA stress were identified, revealing distinct regulatory impacts of these stressors on transcription. These findings establish a framework for investigating the molecular mechanisms underlying stress adaptation in wheat physiology. Full article

Seed germination, a pivotal stage in the plant life cycle, profoundly impacts crop growth and establishment. However, fluctuating environmental conditions like drought, salinity, severe temperatures, and heavy metal toxicity impede seed germination rates and seedling vigor. Seed priming is a pre-sowing seed treatment that involves the controlled hydration of seeds, proven to improve germination rate and stress resilience. It initiates pre-germinative metabolism, including enzyme activity, antioxidant accumulation, hormone modulation, and cellular repair, without radicle emergence. Recent advancements in seed priming, encompassing the application of nanoparticles, phytohormones, and beneficial microbes, have significantly broadened its potential. Despite its proven benefits, challenges such as reduced seed longevity post-priming and variability in species-specific responses remain. This paper revisits the principles and methodologies of seed priming, highlighting its physiological, biochemical, and molecular mechanisms that enhance germination under stress conditions. Additionally, it addresses current challenges and future research directions for optimizing seed priming as a low-cost, eco-friendly approach to improve crop establishment under adverse environments, thereby supporting resilient and sustainable agriculture. Full article

Background/Objectives: Understanding metabolome adjustment under saline–alkaline conditions is crucial for enhancing crop tolerance capacity and ensuring food security. Although soil salinization impairs wheat seedlings’ growth, metabolome plasticity under saline–alkaline stress remains poorly understood. Here, we delved into dynamic physiological and metabolome shifts in wheat seedlings grown on SAS (saline–alkaline soil) on the 7th and 15th days post-germination (DPG). Methods: A self-developed and cultivated high-generation salt–alkali wheat variety (011) was grown on SAS and control soil, followed by comparative physiological, biochemical, and metabolomics analyses of seedlings. Results: The seedlings’ saline–alkaline stress responses were developmentally regulated with reduced growth, increasing accumulation of proline and soluble sugars, and differential antioxidant response. LC-MS-based global metabolomics analysis revealed significant metabolite profile differences, with 367 and 485 differential metabolites identified on the 7th and 15th DPG, respectively, between control and treatment. Upregulation of saccharides, flavonoids, organic acids (citrate cycle-related), phenolic acids, amino acids and derivatives, phytohormones, and sphingolipid metabolism was essential for seedlings’ growth on SAS. The key induced metabolites in seedlings grown on SAS include saccharic acid, trehalose, sucrose, glucose, L-citramalic acid, phellodendroside, scutellarin, anthranilate-1-O-sophoroside, lavandulifolioside, N-methyl-L-glutamate, etc. Up-regulated phytohormones include abscisic acid (3.8-fold, 7th DPG and 3.18-fold, 15th DPG), jasmonic acid (1.93-fold, 15th DPG), and jasmonoyl isoleucine (2.03-fold, 15th DPG). Conclusions: Our findings highlight the importance of ABA and jasmonic acid in regulating salt–alkali tolerance in wheat seedlings. Moreover, this study depicts key pathways involved in salt–alkali tolerance in wheat seedlings and unveils key DMs, offering resources for boosting wheat production on SAS. Full article

Glucose-6-phosphate dehydrogenase (G6PDH) is a critical enzyme in the pentose phosphate pathway, playing an essential role in plant growth, development, and adaptation to abiotic stress. In this study, we identified four members of the G6PDH gene family in the ‘Zunla-1’ genome, designating them as CaG6PDH1-CaG6PDH4. Multiple sequence alignment revealed that the four protein sequences of pepper contain three unique binding sites characteristic of G6PDH: the substrate binding site, the NADP binding site and the Rossmann fold. The phylogenetic tree, motifs, and gene structure analysis indicate that the CaG6PDH gene sequence is relatively conserved and structurally similar, with a close relationship to the sequence of Solanaceae G6PDH members. The collinearity analysis showed that there were two pairs of collinearity between the CaG6PDH genes and the AtG6PDH genes, as well as the SiG6PDH genes. Additionally, numerous cis-elements associated with stress responses, hormone regulation, development, and light responses were identified in the promoter region of the CaG6PDH gene. Furthermore, the various members of the pepper CaG6PDH gene family exhibit specific expression patterns across different tissues and demonstrate significant variations in response to abiotic stress and phytohormone treatments, particularly the CaG6PDH1 and CaG6PDH2 genes. Subcellular localization studies indicate that CaG6PDH2 is located in chloroplasts. We conducted further investigations into the role of CaG6PDH2 in response to cold stress using Virus-Induced Gene Silencing (VIGS) technology. The tissues of seedlings with silenced CaG6PDH2 exhibited significant damage and displayed a more pronounced cold damage phenotype. This observation is further supported by the accumulation of reactive oxygen species (ROS), the activity of antioxidant enzymes, and a reduction in the expression of cold-responsive genes. In conclusion, the findings of this study indicate that CaG6PDH2 plays an important role in cold stress response and may serve as a potential gene for cultivating cold-tolerant pepper varieties. Full article