{"title":"Wax Bloom Dynamics on Sorghum bicolor Under Different Environmental Stresses Reveal Signaling Modules Associated With Wax Production.","authors":"Madison Larson, Marshall Hampton, Lucas Busta","doi":"10.1111/ppl.70349","DOIUrl":"10.1111/ppl.70349","url":null,"abstract":"<p><p>Epicuticular wax blooms are associated with improved drought resistance in many species, including Sorghum bicolor. While the role of wax in drought resistance is well-known, we report new insights into how light and drought dynamically influence wax production. We investigated how wax quantity and composition are modulated over time and in response to different environmental stressors, as well as the molecular and genetic mechanisms involved in such. We combined an in vitro wax induction protocol with GC-MS and RNA-seq measurements to propose a putative signaling pathway for wax bloom induction in sorghum. We also explored the potential of spectrophotometry to aid in monitoring wax bloom dynamics. Spectrophotometric analysis showed primary differences in reflectance between bloom-rich and bloomless tissue surfaces in the 230-500 nm range of the spectrum, corresponding to the blue color channel of photographic data. Our smartphone-based system detected significant differences in wax production between control and shade treatment groups, demonstrating its potential for candidate screening. Overall, our data suggest that wax extrusion can be rapidly modulated in response to light, occurring within days compared to the months required for the changes observed under greenhouse drought/simulated shade conditions. These results highlight the dynamic nature of wax modulation in response to varying environmental stimuli, especially light and water availability.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70349"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144333779","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":"The Role of Lysine Dihydroxyisobutyrylation in Dendrobium huoshanese Under Low-Temperature by Proteomic Analysis.","authors":"Weiyi Rao, Jizhou Fan, Zongping Sun, Chun Wang, Junjie Guan, Yingying Duan, Maoyun Yu, Daiyin Peng, Shihai Xing","doi":"10.1111/ppl.70343","DOIUrl":"https://doi.org/10.1111/ppl.70343","url":null,"abstract":"<p><p>The involvement of lysine dihydroxyisobutyrylation (Khib), a recently identified post-translational modification in plant responses to low temperature stress, is unknown. Here, we performed a comprehensive chloroplast proteome-wide dihydroxyisobutyrylation analysis in Dendrobium huoshanense to explore the potential function of Khib modification in response to low-temperature stress. We identified a total of 13,040 Khib sites in 3281 chloroplast proteins that were significantly differentially regulated under low-temperature stress. Khib-modified proteins were found to be highly associated with proton transmembrane transporter activity, ATPase-coupled ion transmembrane transporter activity, and active monoatomic ion transmembrane transporter activity. The identified Khib sites differentially regulated in response to low-temperature stress were primarily concentrated within AKhib, KKhib, and EKhib motifs. Notably, fructose-1,6-bisphosphate aldolase 2 (DhFBA2) from D. huoshanense, a key chloroplast metabolic enzyme involved in the Calvin-Benson cycle, showed significant Khib modification following low-temperature treatment, with modification occurring at eight Khib sites. Site-directed mutagenesis of the DhFBA2-encoding gene and its expression in yeast revealed that Khib modification at the K338 site is essential for maintaining DhFBA2 enzymatic activity and enhancing low-temperature tolerance. Molecular dynamics simulation and surface electrostatic potential analysis further showed that Khib modification at K338 improved the structural stability of DhFBA2 by reducing its surface affinity to an optimal status, thus promoting its activity and improving low-temperature resistance.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70343"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144326647","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}
Cong Guo, Yan Chen, Ling Wu, Yuqing Jin, Xin Huang, Qingqing Gu, Fan Cao, Peibei Ke, Ying Wang, Yujuan Li
{"title":"Genome-Wide Identification of WRKY Transcription Factors in Lagerstroemia indica and Their Involvement in Color Formation.","authors":"Cong Guo, Yan Chen, Ling Wu, Yuqing Jin, Xin Huang, Qingqing Gu, Fan Cao, Peibei Ke, Ying Wang, Yujuan Li","doi":"10.1111/ppl.70328","DOIUrl":"10.1111/ppl.70328","url":null,"abstract":"<p><p>Lagerstroemia indica, a globally cultivated ornamental plant, is celebrated for its diverse flower and leaf coloration. Although WRKY transcription factors are known regulators of plant pigmentation, their roles in L. indica remain underexplored. This study systematically identified and characterized the WRKY gene family in L. indica to investigate its involvement in color formation. A total of 108 LiWRKY genes were identified in the genome, with 106 classified into three phylogenetic groups. Comprehensive bioinformatics analyses-encompassing conserved domains, phylogeny, chromosomal localization, gene duplication, conserved motifs, exon-intron structures, syntenic gene pairs, cis-acting elements, and interaction networks-uncovered evolutionary relationships and structural-functional features of the LiWRKY family. Transcriptome-based data revealed 37 LiWRKY genes linked to petal coloration. Integration of transcriptomic and metabolomic data with qPCR validation identified six LiWRKY genes as central regulators of leaf color variation. Notably, LiWRKY100 displayed distinct expression profiles across leaf color phenotypes, underscoring its critical regulatory role. These results advance the understanding of LiWRKY gene evolution, structure, and function, while demonstrating their direct contributions to both floral and foliar pigmentation. The study establishes a foundation for leveraging WRKY genes in the genetic enhancement of L. indica's ornamental traits, offering actionable targets for future breeding programs.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70328"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144275555","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}
Yong Qiang Gao, Su Li, Hao Yu Wang, Chuan Jin Shan, Lu Zheng, Ceng Ceng Tian, Jing Kun Zhang, Yi Fan Zhang, Da Li Zeng, Jiu Huang, Ren Fang Shen, Hua Wang, Xiao Fang Zhu
{"title":"Identification of a Novel Glycosyl Transferase Family 17 Protein Involved in Cd Accumulation in Rice (Oryza sativa).","authors":"Yong Qiang Gao, Su Li, Hao Yu Wang, Chuan Jin Shan, Lu Zheng, Ceng Ceng Tian, Jing Kun Zhang, Yi Fan Zhang, Da Li Zeng, Jiu Huang, Ren Fang Shen, Hua Wang, Xiao Fang Zhu","doi":"10.1111/ppl.70323","DOIUrl":"https://doi.org/10.1111/ppl.70323","url":null,"abstract":"<p><p>Cadmium (Cd) is a heavy metal widely distributed in the environment that poses a significant threat to living organisms because of its strong mobility and toxicity. In this study, a novel gene named Osß-glu from the glycosyltransferase (GT) family was investigated for its role in the Cd stress response in rice. Various experiments were conducted using the japonica cultivar Nipponbare (Nip) and its mutants (Osß-glu-1 and Osß-glu-2). The results showed that Osß-glu was specifically induced by Cd stress rather than by other mineral deficiencies. The Osß-glu mutants exhibited higher sensitivity to Cd stress, with more significant inhibition of root elongation, reduced biomass, and increased Cd accumulation in the roots, shoots, and xylem sap than Nip. Nitro-Blue Tetrazolium (NBT) staining indicated a larger acumulation of superoxide anion in the mutant roots under Cd stress, 3,3'-Diaminobenzidine (DAB) staining showed more pronounced H<sub>2</sub>O<sub>2</sub> accumulation, and Evans Blue staining revealed more dead cells, demonstrating more severe reactive oxygen species (ROS) accumulation and cell damage in mutant roots. Moreover, the mutants had higher hemicellulose content and elevated Cd-binding capacity in the root cell wall, as well as abnormal expression of genes related to Cd absorption and translocation. Overall, multiple lines of evidence suggest that Osß-glu plays a crucial regulatory role in the response of rice to Cd stress, acting as an inhibitor of Cd accumulation. This contributes to a better understanding of the precise control network for Cd tolerance in rice, providing a basis for breeding rice varieties with lower Cd uptake.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70323"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144286125","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":"Exploitation of volatile organic compounds for rice field insect-pest management: current status and future prospects.","authors":"Kali Prasad Pattanaik, Somanatha Jena, Arabinda Mahanty, Basana Gowda Gadratagi, Naveenkumar Patil, Govindharaj Guru-Pirasanna-Pandi, Prasanthi Golive, Shyamaranjan Das Mohapatra, Totan Adak","doi":"10.1111/ppl.70240","DOIUrl":"https://doi.org/10.1111/ppl.70240","url":null,"abstract":"<p><p>Insect pests are major biotic factors that cause significant damage to rice crops, posing a major challenge to global rice production. Synthetic pesticides are the most effective and reliable technique for pest management. However, their high cost, non-biodegradability, and adverse effects on human and environmental health have driven the search for more sustainable, eco-friendly, and economically viable alternatives. Recently, Volatile Organic Compounds (VOCs), both plant-derived or synthetically made, have emerged as a promising tool for insect pest management in diverse agricultural practices. Rice plants continuously release VOCs that facilitate tritrophic interactions among the plants, their herbivores, and the natural enemies of these herbivores, highlighting their ecological importance. VOCs are being explored as semiochemicals in pest management strategies in various crops, including rice. Although applications of VOCs remain in the laboratory stage, they hold great promise for future field implementation. This review highlights the role of rice VOCs in herbivore-natural enemy interactions and explores the factors regulating their release. It provides a comprehensive analysis of recent advancements, ongoing challenges, and prospects in using VOCs for rice pest management. Additionally, the review emphasizes the integration of VOCs with precision agriculture and genetic engineering approaches along with advanced monitoring technologies, to develop sustainable and effective pest management practices in rice agroecosystems.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70240"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144035649","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":"Anthocyanin biosynthesis, quality, and yield in purple sweet potatoes: responses to different potassium fertilizer.","authors":"Jingwei Huang, Qiang Wang, Qingcheng Qiu, Liang Zou, Xueshan Shen, Yan Wan, Huijuan Qu","doi":"10.1111/ppl.70247","DOIUrl":"https://doi.org/10.1111/ppl.70247","url":null,"abstract":"<p><p>Purple sweet potato (PSP) (Ipomoea batatas (L.) Lam) is a nutrient-rich \"K-favoring\" crop. The reasonable application of potassium is an important means of improving the quality and yield of PSP. We designed four different forms of potassium fertilizer treatments: K<sub>2</sub>SO<sub>4</sub>, KCl, KH<sub>2</sub>PO<sub>4</sub>, and K<sub>2</sub>HPO<sub>4</sub>, and used qRT-PCR and HPLC techniques to explore their differences in anthocyanin synthesis, accumulation, quality, and yield in PSP tubers. Our findings indicate that potassium fertilizer treatment enhances the expression of structural genes such as CHI (chalcone--flavonone isomerase), F3H (naringenin,2-oxogluturate 3-dioxygenase-like), F3‧H (flavonoid 3'-monooxygenase), ANS (leucoanthocyanidin dioxygenase-like), DFR (dihydroflavonol 4-reductase-like), and CHS (chalcone synthase), which encode key enzymes of the anthocyanin metabolism pathway. This is achieved by stimulating the high levels of expression of the transcription factor MYB, which controls anthocyanin accumulation. Consequently, this leads to increased activities of key anthocyanin biosynthetic enzymes Phenylalanine ammonia lyase (PAL, EC 4.3.1.5), chalcone isomerase (CHI, EC 5.5.1.6), dihydroflavonol 4-reductase (DFR, EC 1.1.1.219), and UDP-galactose flavonoid 3-O-galactosyltransferase (UFGT, EC 2.4.1.234), thereby promoting the synthesis and accumulation of anthocyanins within PSP tubers. This ultimately improves tuber quality and yield. Analysis conducted through hierarchical clustering heat map, principal component analysis (PCA), and comprehensive evaluation revealed that PSP exhibits varying sensitivities to different forms of potassium fertilizer, with KCl treatment significantly enhancing anthocyanin production efficiency. Our results will provide a theoretical basis and data support for the rational selection of potassium fertilizer types for actual PSP production.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70247"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143975702","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}
Farinaz Vafadar, Mohammad Mahdi Majidi, Ali Rabbani
{"title":"Genetic insight into physiological and spectral reflectance indices of synthetic wheat germplasm in various phenological stages under salinity stress.","authors":"Farinaz Vafadar, Mohammad Mahdi Majidi, Ali Rabbani","doi":"10.1111/ppl.70244","DOIUrl":"https://doi.org/10.1111/ppl.70244","url":null,"abstract":"<p><p>Spectral reflectance indices (SRIs) are increasingly recognized as valuable tools in wheat breeding programs for assessing traits that typically require destructive measurements. Little is known about the application of non-descriptive methods in synthetic wheat and the effect of phenological stage. This study assessed variation and genetic parameters of SRIs and physiological parameters in a panel of synthetic wheat under both control and salinity conditions as well as the efficacy of SIR indices for selection across different phenological stages. Results indicated that salinity stress significantly reduced grain yield and relative water content while increasing ascorbate peroxidase (APX) enzyme activity across all growth stages. APX, peroxidase (POD), and the Green Difference Vegetation Index (GDVI) showed the highest heritability and genotypic coefficient of variation (GCV) across all phenological stages, suggesting strong genetic control over these indices. The Normalized Difference Vegetative Index (RNDVI) also demonstrated a similar trend under control conditions across all phenological stages. Principal Component Analysis (PCA) indicated that assessing SRIs concerning grain yield and physiological parameters was more effective during the anthesis and maturity stages than at milking. However, PCA effectively identified high-yielding and salt-tolerant genotypes during the milking stage, particularly at maturity. Overall, the SRIs analysis in wheat genotypes highlights their potential for optimizing selection timing and improving precision in breeding programs.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70244"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144128387","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":"Metabolites in Cellular Leachate as Biomarkers for the Nature and Severity of Injury Following a Short vs. Prolonged Freezing Stress.","authors":"Rajeev Arora, Keting Chen","doi":"10.1111/ppl.70273","DOIUrl":"https://doi.org/10.1111/ppl.70273","url":null,"abstract":"<p><p>Freeze injury is typically quantified by measuring electrolyte leakage from plant tissues exposed to a freeze-thaw cycle, whereby higher leakage indicates greater injury. The severity of stress is also assessed by the ability (or lack thereof) of the injured tissue to recover, wherein reduced leakage during the post-thaw period relative to right after thaw indicates recoverable injury. In this study, spinach leaves were injured to various degrees by freezing them for different durations at a fixed sub-zero temperature. We explored the cellular nature of freeze-thaw injury by comparing the profiles of cellular metabolites that were leaked from reversibly and/or irreversibly injured leaves. A total of 47 metabolites were, thus, detected in the leachate, including 8 sugars, 20 amino acids, GABA, uracil, adenine, palmitic acid, ferulic, coumaric acid, and other organic/inorganic acids involved in primary and secondary metabolism (e.g., citric acid, phosphoric acid, coumaric acid, etc.). Combined multivariate metabolome analysis, including principal component analysis, hierarchical clustering, and partial least square discriminant analysis, together identified 14 key metabolites mainly responsible for distinguishing the reversible vs. irreversible injury. These metabolites are also indicators for various lesions, including structural/functional perturbations to cellular components (cell wall, chloroplast, vacuole, plasma membrane, nucleic acids), disruption of metabolic homeostasis (antioxidant system, cytoplasmic pH, Kreb's cycle), protein degradation, and hypoxia.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70273"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144128389","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}
Eman Ryad Elrefaay, Michael Melzer, Mónika Hrtyan, Aleš Pěnčík, Ondřej Novák, Jürgen Kleine-Vehn, Vanesa Beatriz Tognetti
{"title":"Crosstalk Between Auxin Signalling and Growth Regulating Factor 5: Implications for Chloroplast Division and Leaf Development.","authors":"Eman Ryad Elrefaay, Michael Melzer, Mónika Hrtyan, Aleš Pěnčík, Ondřej Novák, Jürgen Kleine-Vehn, Vanesa Beatriz Tognetti","doi":"10.1111/ppl.70315","DOIUrl":"https://doi.org/10.1111/ppl.70315","url":null,"abstract":"<p><p>Chloroplasts are the sites of photosynthesis but also host essential metabolic and biosynthetic pathways; therefore, the regulation of the chloroplast population is of crucial importance for the viability of the plant. Chloroplast division is closely linked to leaf development, but the coordination of cell expansion, division, and chloroplast multiplication at the molecular level is still poorly understood. Auxin signalling influences leaf growth and may also mediate chloroplast biogenesis and proliferation. Most studies focused on auxin and the development of chloroplasts in the fruit, emphasising the need for further research on leaf tissue. Overexpression of Growth Regulating Factor 5 (35S:GRF5) increases cell and chloroplast division in Arabidopsis thaliana, resulting in larger leaves with more chloroplasts per cell. In this study, we utilised 35S:GRF5 plants as a model to identify auxin control points that regulate chloroplast division. By examining the impact of changes in auxin homeostasis on chloroplast division and mesophyll cell size and by analysing crosses with selected auxin homeostasis genes, we found that reactive oxygen species-auxin crosstalk influences chloroplast multiplication during the cell expansion phase. Evidence indicates that GRF5 modulates auxin responsiveness by regulating the expression of UDP-glucosyltransferase UGT74E2 and PIN-LIKES3/5, which are key players in intracellular auxin homeostasis. These findings provide potential targets for modulating chloroplast abundance to improve photosynthetic efficiency in crops and highlight key areas for further research.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70315"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144249229","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}
Sunita Kataria, Md Intesaful Haque, Andrej Filacek, Maria Barboricova, Jana Ferencova, Meeta Jain, Anshu Rastogi, Marian Brestic
{"title":"Enhancing UV-B Tolerance in Radish and Mung Bean Plants Using Magnetic Iron Oxide Nanoparticles Foliar Application.","authors":"Sunita Kataria, Md Intesaful Haque, Andrej Filacek, Maria Barboricova, Jana Ferencova, Meeta Jain, Anshu Rastogi, Marian Brestic","doi":"10.1111/ppl.70285","DOIUrl":"https://doi.org/10.1111/ppl.70285","url":null,"abstract":"<p><p>This study investigates the potential of magnetic iron oxide nanoparticles (MIONPs) in mitigating ultraviolet-B radiation (UV-B) induced physiological damage in radish (Raphanus sativus L.) and mung bean (Vigna radiata). Screening of the seed vigour indices identified 1500 mg L<sup>-1</sup> MIONPs as the optimal concentration for radish and 100 mg L<sup>-1</sup> for mung bean for seed vigour improvement. After the first true leaf appeared (~15 days), plants were exposed to different UV-B intensities: control (UV0, 0 mW m<sup>-2</sup>), moderate (UV1, 26 mW m<sup>-2</sup>), and high (UV2, 53 mW m<sup>-2</sup>), with or without foliar MIONPs application. Results showed that UV-B significantly decreased the net photosynthesis rate (Pn) by 32% in radish and 65% in mung bean after UV2 exposure. Fluorescence parameters, including photosystem II (PSII) efficiency and photosynthetic performance (PI<sub>abs</sub>), were also impaired by UV-B. UV-B stress led to a decline in plant growth, leaf area, biomass accumulation, and chlorophyll content while increasing antioxidant enzyme activities, flavonoids, anthocyanins, malondialdehyde (MDA), and hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) levels. However, MIONPs treatment enhanced UV-B tolerance by improving pigment content, PSII efficiency, Pn, leaf area, and biomass accumulation while reducing MDA and H<sub>2</sub>O<sub>2</sub> levels, thus improving overall plant physiological health. In the leaf model of energy flux, MIONPs-treated plants showed more active reaction centers and improved electron transport. The OJIP curves differed under UV-B stress, with increasing UV-B stress showing decreased fluorescence intensity at the IP phase. However, plants treated with MIONPs showed higher fluorescence intensity specifically at the IP phase, suggesting their protective effect. The UV sensitivity index (UV-SI) revealed that mung bean is more UV-sensitive than radish. MIONPs treatment increased UV-SI values and enhanced the plant tolerance towards UV-B. The results suggest that the application of MIONPs could improve UV-B resistance in future agricultural practices.</p>","PeriodicalId":20164,"journal":{"name":"Physiologia plantarum","volume":"177 3","pages":"e70285"},"PeriodicalIF":5.4,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144216591","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}