Physiologia plantarum最新文献

{"title":"ABA Signaling De-Repression Coordinates With Cytokinin to Drive Large Petal Formation in Brassica napus.","authors":"Meng-Xue Cheng, Jia-Hui Gao, Li-Na Xu, Zheng-Xi Long, Li-Juan Wei, Zhen Wang, Liu Miao","doi":"10.1111/ppl.71108","DOIUrl":"10.1111/ppl.71108","url":null,"abstract":"<p><p>Petal size is a critical agronomic trait influencing pollination efficiency and yield in field crops. However, the cellular basis and upstream hormonal interplay governing petal size in Brassica napus remain unclear. In this study, utilizing a natural variation population of \"Zhongshuang 11\", we investigated biological mechanisms underlying petal development through integrated phenotypic screening, paraffin section-based cytological analysis, targeted hormone metabolomics, and transcriptome. The results revealed that the single-flower area of large petals (BEP; 13.0 mm²) was significantly larger than that of wild type (8.5 mm²) and small petals (SEP; 6.8 mm²), a difference primarily attributable to increased petal width. The formation of BEP was due to a more than two-fold increase in cell number per unit area, rather than cell expansion. Furthermore, salicylic acid (SA), jasmonic acid (JA), abscisic acid (ABA), and cytokinins (CK) were significantly enriched in BEP petals, whereas brassinosteroid (BR) content was lowest. Correlation analysis indicated a significant positive correlation between ABA and JA (r = 0.95). Negative regulators of ABA signaling, BnaC09.ABI1 and BnaA01.PP2CA, were significantly downregulated, while core cell cycle genes were highly expressed in BEP. An \"ABA de-repression\" model was proposed; a hormonal milieu characterized by high concentrations of SA, JA, and CK, coupled with low BR levels, is associated with the downregulation of negative regulators of ABA, potentially alleviating constraints on cell cycle progression to facilitate cell proliferation. This study elucidates the molecular and physiological basis of petal size in rapeseed and provides a theoretical foundation for enhancing outcrossing and yield through floral trait modification.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71108"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13557834/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148920013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Funneliformis mosseae Modulates Root 14-3-3 Gene Expression to Enhance Drought Tolerance in Trifoliate Orange: A Molecular-Physiological Integration.","authors":"Feng-Ling Zheng, Ke-Xing Yan, Zhen Liu, Ying-Ning Zou, Qiang-Sheng Wu, Qing-Ping Yi, Mashael Daghash Alqahtani","doi":"10.1111/ppl.71110","DOIUrl":"10.1111/ppl.71110","url":null,"abstract":"<p><p>The 14-3-3 family proteins are involved in plant metabolism and stress signal transduction, while whether and how they contribute to the enhancement of host drought tolerance by arbuscular mycorrhizal (AM) fungi remains unclear. This study aimed to identify the 14-3-3 gene family (GRF) in trifoliate orange (Poncirus trifoliata) and analyze their responses in roots to drought and inoculation with the AM fungus Funneliformis mosseae, integrating molecular data with physiological assessments. Despite drought-inhibited AM fungal colonization and soil mycelium length, AM inoculation markedly increased plant biomass, root growth, soluble sugars, antioxidant enzyme activities, and phytohormone levels under drought. Fifteen PtGRF members were identified with variable gene structures and abscisic acid/stress-related promoter elements. Drought stress predominantly suppressed the expression of most PtGRF genes in non-AM plants, while it triggered the upregulation of a specific subset (PtGRF3, 6, 9, 13, 14) in AM plants. Inoculation with AM fungi under drought conditions dramatically modulated the host's transcriptional response, significantly upregulating 10 of the 13 detected PtGRFs, most notably PtGRF13. Principal component and correlation analyses delineated distinct functional associations among PtGRF members: PtGRF1, PtGRF2, PtGRF5, and PtGRF15 were closely linked to soluble sugar accumulation and antioxidant defense, while PtGRF3, PtGRF6, PtGRF8, PtGRF9, and PtGRF13 showed stronger integration with abscisic acid and isopentenyl adenine. In summary, inoculation with AM fungi enhanced drought tolerance in trifoliate orange by modulating the expression of drought-responsive specific PtGRF genes, which functioned as integrated signaling modules to coordinate sugars, antioxidant defense, and abscisic acid levels.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71110"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13562829/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148930914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterising Thermotolerance Traits and Their Acclimation Potential in Two Important Forestry Species of Eucalyptus.","authors":"Ignatious Matimati, Mark J Hovenden, Chris J Blackman","doi":"10.1111/ppl.71119","DOIUrl":"10.1111/ppl.71119","url":null,"abstract":"<p><p>As climate warming and more frequent heatwave events cause increasing damage to native and managed forest trees, there is an urgent need to characterise species thermotolerance thresholds and define their capacity to acclimate to warmer growth conditions. This study characterised a range of thermotolerance traits related to thresholds of photosystem II (PSII) function under increasing temperature (T_crit) and heat load in saplings and adults of two commercially and ecologically important eucalypt species, Eucalyptus globulus and E. nitens. We also measured photosynthetic and leaf economic traits and examined the acclimation response of leaf thermotolerance in saplings grown under different temperatures and exposed to heatwave conditions. Saplings and adults of each species recorded similar optimum temperatures (T_opt) for maximum photosynthesis (E. globulus = 26.8°C and E. nitens = 25.9°C) and similar leaf thermotolerance thresholds (T_crit~42°C). When grown under different day/night temperatures (cool, 20/10°C; mild, 25/15°C; and warm, 30/20°C), we found evidence of plasticity in T_crit in E. globulus saplings grown under cool (T_crit = 42°C) versus warm (T_crit = 45°C) conditions, while T_crit in E. nitens saplings did not significantly vary. During heatwave conditions, PSII dysfunction increased in saplings of both species across all growth conditions with increasing heatwave intensity, with substantial loss of function at 45°C. We establish for the first time heat intensity-duration relationships and define thermal acclimation potential for E. globulus and E. nitens saplings. These results provide forest managers with insights into canopy vulnerability when optimising species selection for heat-prone sites and developing proactive climate adaptation strategies for plantations in a warming environment.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71119"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13585471/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148991126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Contrasting Embryogenic Trajectories Reveal Spatial Control as a Key Determinant of Embryogenic Competence in Theobroma cacao L.","authors":"Stefhania Alzate-Lozano, Inaê Mariê de Araújo Silva Cardoso, Claudia Franca Barros, Uilson Vanderlei Lopes, Jonny Everson Scherwinski-Pereira","doi":"10.1111/ppl.71072","DOIUrl":"10.1111/ppl.71072","url":null,"abstract":"<p><p>Somatic embryogenesis (SE) in Theobroma cacao is a micropropagation technique of great importance but remains constrained by genotype recalcitrance. The cellular and molecular mechanisms distinguishing regenerative from non-regenerative responses remain poorly understood. Here, we elucidate the ontogenetic events governing embryogenic competence by comparing responsive genotypes (CCN-51 and 752) with a recalcitrant one (PH16). Our results demonstrate that SE success in cacao is not determined by cell proliferation speed, but rather by a slow, organized, and spatially confined developmental trajectory. Through histological and immunofluorescence analyses, we show that responsive genotypes establish a focused response within procambial tissues. This leads to the formation of late, localized auxin maxima (after 42 days), which are essential for organizing morphogenesis. In contrast, the recalcitrant genotype exhibits a rapid, diffuse, and disorganized response that fails to establish necessary hormonal gradients, resulting in developmental collapse. We conclude that embryogenic competence in cacao should be redefined: it is not merely an induction event, but the precise orchestration of a developmental program dependent on the controlled reactivation of a vascular stem cell niche. These findings provide novel morphological and hormonal markers for selecting elite genotypes and offer new strategies to overcome recalcitrance in cacao.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71072"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13507766/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148819300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proposed Dual Mechanisms of Arbuscular Mycorrhizal Fungi in Enhancing Soybean Resistance to Continuous Cropping via the LACS8-Palmitoleic Acid Axis.","authors":"Lin Pan, Lina Yu, Yunshu Wu, Hao Shi, Lei Wang, Baiyan Cai","doi":"10.1111/ppl.71127","DOIUrl":"https://doi.org/10.1111/ppl.71127","url":null,"abstract":"<p><p>Intensive soybean (Glycine max L.) production is severely constrained by continuous cropping obstacles, which induce root oxidative stress and lipid peroxidation. These processes compromise cell membrane integrity, inhibiting plant development, and ultimately reducing yield and quality. This study investigated whether the alleviation of continuous cropping obstacles by arbuscular mycorrhizal fungi (AMF) was associated with fatty acid synthesis and root membrane lipid systems. Through Funneliformis mosseae (F. mosseae)-inoculated pot experiments, we integrated physiological, transcriptomic, proteomic, and metabolomic analyses to investigate the effects of AMF inoculation on fatty acid synthesis and root membrane lipid systems in soybean roots. Results showed that F. mosseae inoculation effectively mitigated membrane lipid peroxidation and promoted growth. Specifically, it significantly increased plant height, root metabolic activity, and superoxide dismutase (SOD) activity by 21.23%, 49.34%, and 46.17%, respectively. Conversely, hydrogen peroxide (H₂O₂) content, lipoxygenase (LOX) activity, and malondialdehyde (MDA) content decreased by 34.88%, 25.82%, and 47.83%, respectively. Furthermore, LACS8 upregulation was associated with fatty acid biosynthesis and palmitoleic acid accumulation in F. mosseae-inoculated plants. In summary, these results suggest a dual protective mechanism involving structural membrane repair and antioxidant defense, associated with the LACS8-palmitoleic acid pathway, and potentially related to the alleviation of soybean continuous cropping obstacles. This multi-omics study provides new insights into the potential role of fatty acid biosynthesis in soybean adaptation to continuous cropping under AMF inoculation. These findings deepen the understanding of AMF-plant stress resistance and support utilizing AMF inoculants for sustainable soybean production.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71127"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149017756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Persistent Epigenetic Reprogramming Is Associated With Contrasting Drought-Response Strategies in Citrus Scion-Rootstock Systems.","authors":"Monique Ayala Araújo da Silva, Fredson Dos Santos Menezes, Iris Sammarco, Lucas da Silva Costa, Claudia Fortes Ferreira, Soares Filho, Fabienne Micheli, Maurício Antônio Coelho-Filho, Abelmon da Silva Gesteira","doi":"10.1111/ppl.71113","DOIUrl":"10.1111/ppl.71113","url":null,"abstract":"<p><p>Recurrent drought limits the productivity of perennial crops such as citrus, whose tolerance to water deficit largely depends on scion-rootstock interactions. Although physiological responses to recurrent drought are well documented, the epigenetic states associated with these responses remain poorly understood, limiting the use of epigenetic variation to improve drought resilience. Here, we investigated whole-genome DNA methylation profiles and transcriptional responses in \"Pera-D6\" sweet orange (LP) grafted onto two rootstocks with contrasting physiological strategies for coping with water deficit: \"Rangpur\" lime (RL), associated with dehydration avoidance through enhanced water acquisition, and \"Sunki Maravilha\" mandarin (SM), associated with tighter regulation of transpiration and physiological adjustments under stress. Grafted plants were exposed to three cycles of water deficit followed by rehydration. In the scion, we detected rootstock-dependent methylation dynamics, with LP/RL exhibiting broader patterns of methylation change and LP/SM showing a more targeted response. In the LP/SM combination, drought-associated differentially methylated regions were linked to genes involved in photosynthesis, stomatal regulation, and transcriptional processes. For several stress-responsive genes, promoter methylation changes coincided with qualitative trends in gene expression; however, no significant methylation-expression correlations were detected after multiple-testing correction. These findings indicate that recurrent drought is associated with rootstock-dependent persistent DNA methylation patterns with potential functional relevance. Overall, the results highlight the importance of considering epigenetic variation in studies of drought response and suggest that rootstock selection may play a role in shaping regulatory responses to water deficit in citrus.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71113"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13597148/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149025856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of GSI and UI in Solanum chilense and Its Hybrids With S. lycopersicum: Uncovering Genotype-Specific Mechanisms and Candidate Genes.","authors":"Pauline Moreels, Servane Bigot, Corentin Defalque, Marie Eve Renard, Juan Pablo Martinez, Stanley Lutts, Muriel Quinet","doi":"10.1111/ppl.71125","DOIUrl":"https://doi.org/10.1111/ppl.71125","url":null,"abstract":"<p><p>Reproductive barriers in wild tomato relatives limit the introgression of valuable stress-resistance traits into cultivated tomato, yet the molecular mechanisms governing these barriers in Solanum chilense remain poorly understood compared to model species like Nicotiana alata or Solanum pennellii. This study aimed to characterize the phenotypic and transcriptional architecture of gametophytic self-incompatibility and unilateral incompatibility in Solanum chilense and its interspecific hybrids with Solanum lycopersicum. We combined phenotypic assays of pollen tube growth and fruit set with quantitative gene expression profiling of candidate pistil-side factors across developmental stages and cross-types, supplemented by comparative genomic mapping. We found that the pistil's species identity, rather than compatibility status, was the primary driver of transcriptional variation, indicating a dominant genotype-specific background effect. Expression of the PELPIII-120K-TTSL-TTSR gene cluster and HT-A correlated strongly with barrier strength, while hybrids displayed a partial breakdown of incompatibility linked to altered expression balance. These results demonstrate that reproductive isolation in Solanum chilense relies on a complex, genotype-specific regulatory network rather than universal factors. This insight refines our understanding of plant reproductive evolution and identifies specific molecular targets to overcome hybridization bottlenecks for crop improvement.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71125"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149025839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of AgBiS₂/CuO Nanocomposite on Barley (Hordeum vulgare L.): Phytotoxicity, Genotoxicity, and Photosynthesis via Interfacial Charge Transfer.","authors":"Yassine Slimani, Sarah Almofty, Huseyin Tombuloglu, Abdelkrim Mekki, Qasem Drmosh","doi":"10.1111/ppl.71137","DOIUrl":"https://doi.org/10.1111/ppl.71137","url":null,"abstract":"<p><p>Engineered nanomaterials are increasingly used in agriculture. Accordingly, understanding their interactions with soil-plant systems became essential to ensure environmental safety. This study investigates the rational synthesis and characterization of a novel AgBiS₂/CuO nanocomposite and evaluates its phytotoxic and genotoxic impacts on barley (Hordeum vulgare L.). Structural and surface analyses were performed using XRD, FTIR, XPS, and SEM-EDX. The interfacial charge transfer was studied by optical analyses and photoluminescence quenching. The biological effects were evaluated by measuring the photosynthetic activity (F_v/F_m, NPQ, Y(II), and ETR), genomic alterations through RAPD-PCR analysis, and in vitro cytotoxicity assays. Analyses identified a high-purity biphasic architecture with efficient interfacial charge transfer modulating reactive oxygen species (ROS) generation. Optical analyses also showed significant quenching of photoluminescence intensity in the nanocomposite compared to pristine components. The prepared nanocomposite showed good biocompatibility, although high concentrations (≥ 2000 mg L^-1) caused dose-dependent growth retardation and photosynthetic activity inhibition. Importantly, no genotoxic changes in barley DNA were seen through the RAPD-PCR analysis. Additionally, the viability of cells was still over 80% at doses up to 125 μg mL^-1. These results indicate that the heterojunction interface mostly stabilizes the material against DNA damage and prevents acute genomic instability. The experiments of in vitro cytotoxicity demonstrated the great biocompatibility of the prepared nanocomposite, thus validating its safety profile. The outcomes of this study establish that the interfacial engineering of metal sulfide/oxide composites may decrease environmental concerns and provide opportunities for the design of high-performance nanomaterials or nanocomposites with low toxicity to agricultural crops and soil health.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71137"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149113487","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitric Oxide Enhances Salt Tolerance in Ginger Seedlings Through Phytohormone Homeostasis and Starch and Sugar Metabolism.","authors":"Yue Zhong, Shijia Zhu, Jinlian Yuan, Yiming Yang, Manli Qin, Zehan Zhu, Xiang Ma, Jiayu Zhai, Shouhui Wei, Lijuan Wei, Yiqing Liu","doi":"10.1111/ppl.71139","DOIUrl":"https://doi.org/10.1111/ppl.71139","url":null,"abstract":"<p><p>Nitric oxide (NO) is a key signaling molecule regulating plant stress responses. In our study, the NO donor sodium nitroprusside (SNP) significantly promoted ginger seedling growth under salt stress, while treatment with the NO scavenger cPTIO resulted in an opposite response, supporting the involvement of NO in salt-stress responses. Transcriptome profiling of ginger leaves identified 2252 differentially expressed genes (DEGs), which were enriched in 55 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Further, analysis showed that 19 DEGs were enriched in plant hormone signal transduction, while 16 DEGs were enriched in starch and sugar metabolism. NO treatment increased the levels of indole-3-acetic acid (IAA), gibberellin 3 (GA₃), and trans-zeatin (ZR), while reducing the levels of abscisic acid (ABA), methyl jasmonate (MeJA), and brassinosteroid (BR). Moreover, NO promoted the accumulation of soluble sugars and sucrose and enhanced the activities of key enzymes involved in starch and sucrose metabolism, thereby effectively improving osmotic adjustment. Collectively, NO improves antioxidant capacity, maintains endogenous phytohormone balance, and enhances osmotic adjustment, ultimately alleviating salt stress damage in ginger seedlings.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71139"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149113562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combined Day-Night Heat Damage in Soybean Is Driven by Nighttime Warming.","authors":"Gabriel Ferraz Guimarães, Jéssica de Jesus Santos, Rafael Vasconcelos Ribeiro, Milton Costa Lima Neto","doi":"10.1111/ppl.71100","DOIUrl":"10.1111/ppl.71100","url":null,"abstract":"<p><p>Asymmetric warming, characterized by faster increases in nighttime than daytime temperatures, is an emerging threat to crop performance. However, the interactive physiological effects of day versus night heat remain insufficiently resolved in soybean (Glycine max L. Merr.). Here, we evaluated soybean responses to 4 day/night thermal regimes (28°C/22°C, 40°C/22°C, 28°C/28°C, and 40°C/28°C) to test whether nighttime warming is the dominant driver of stress disruption. Isolated daytime heat (40°C/22°C) enhanced photosynthetic performance and maintained biomass, indicating short-term functional plasticity. In contrast, treatments including elevated nighttime temperature impaired pre-dawn rehydration, reduced leaf water status, and intensified membrane damage, with the strongest effects under combined heat (40°C/28°C). Combined stress also caused severe stomatal limitation of CO₂ assimilation, depletion of soluble sugars, accumulation of proline and glycine betaine, and strong activation of antioxidant enzymes accompanied by high H₂O₂ and TBARS levels, indicating that oxidative load exceeded detoxification capacity. Multivariate integration reinforced this pattern by clearly separating combined heat from all other treatments and placing nighttime warming as the central axis of physiological disruption. Together, our findings demonstrate that restricted nocturnal recovery is a key mechanism underlying synergistic damage under sustained day-night heat, highlighting nighttime metabolism and overnight hydraulic recovery as priority targets for improving soybean heat resilience.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"178 5","pages":"e71100"},"PeriodicalIF":4.0,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13677161/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149220587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}