Plant Physiology and Biochemistry最新文献

{"title":"MdPP2AC interacting with MdCLC to mediate ALA-induced salt tolerance in apple","authors":"Kun Xiang ,&nbsp;Jiayi Zhou ,&nbsp;Jianting Zhang,&nbsp;Mohsin Iqbal,&nbsp;Liangju Wang","doi":"10.1016/j.plaphy.2026.111150","DOIUrl":"10.1016/j.plaphy.2026.111150","url":null,"abstract":"<div><div>5-Aminolevulinic acid (ALA) is a plant growth regulator that enhances salt tolerance, yet the underlying mechanisms remain unclear. In this study, we investigated the function and molecular mechanism of the Protein Phosphatase 2A (PP2A) catalytic subunit MdPP2AC in ALA-induced salt tolerance in detached leaves, calli, and rooted plantlets of ‘Gala’ apple (<em>Malus</em> × <em>domestica</em>). Results showed that pretreatment with ALA before NaCl stress significantly alleviated NaCl-induced damage, enhanced antioxidant enzyme activities, and improved chloride (Cl⁻) interception in the roots with less transport to the aboveground. Further analysis revealed that the PP2A activity and <em>MdPP2AC</em> expression were induced by NaCl and further by ALA. Functional studies showed that overexpressing (OE)-<em>MdPP2AC</em> enhanced salt tolerance, whereas RNA interference (RNAi)-<em>MdPP2AC</em> or application of cantharidin (CT, a specific inhibitor of PP2A activity) compromised salt tolerance, but exogenous ALA mitigated CT-aggravated salt injury. Yeast two-hybrid (Y2H), bimolecular fluorescence complementation (BiFC), luciferase complementation imaging (LCI), sequence truncation and site-directed mutagenesis assays confirmed that MdPP2AC can interact with the chloride channel protein MdCLC-c2, and the C-terminal Glu⁶⁸⁴ residue of MdCLC-c2 is indispensable for the molecular interaction and Cl⁻ transport activation. Function identification with <em>Δgef1</em> mutant yeast showed that <em>MdCLC-c2</em> transformation promoted intracellular Cl⁻ accumulation as well as cell salt tolerance, and the effects were further promoted by <em>MdPP2AC</em> transformation and exogenous ALA. Collectively, we propose that MdPP2AC mediates ALA-induced salt tolerance in apple by interacting with MdCLC-c2, which promotes Cl⁻ sequestration into root vacuoles with less transport to the aboveground, thus maintaining Cl⁻ homeostasis at the cellular and plant levels. These findings reveal a novel mechanism whereby PP2AC modulates chloride channel function to maintain ion homeostasis within the ALA signaling pathway, providing critical insights into ALA-mediated apple salt tolerance.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111150"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146220783","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":"Arbuscular mycorrhizal fungi enhance walnut juglone accumulation via coordinated induction of β-glucosidase genes (JrBGLUs)","authors":"Xiao-Qing Liu ,&nbsp;Xiao-Hong Xu ,&nbsp;Ying-Ning Zou ,&nbsp;Yong-Jie Xu ,&nbsp;Abeer Hashem ,&nbsp;Elsayed Fathi Abd_Allah ,&nbsp;Qiang-Sheng Wu","doi":"10.1016/j.plaphy.2026.111161","DOIUrl":"10.1016/j.plaphy.2026.111161","url":null,"abstract":"<div><div>Juglone is a pivotal allelopathic and defensive secondary metabolite in walnuts (<em>Juglans regia</em>), yet the regulation mechanisms govering its biosynthesis, particularly during mycorrhization, remain poorly understood. This study investigated the effects of five arbuscular mycorrhizal fungi (AMF) species, including <em>Paraglomus occultum</em>, <em>Acaulospora scrobiculata</em>, <em>Rhizophagus intraradices</em>, <em>Funneliformis mosseae</em>, and <em>Diversispora spurca</em> on walnuts. The changes in plant growth, root morphology, β-glucosidase activity, juglone accumulation, and the expression of β-glucosidase gene family (<em>JrBGLUs</em>) were studied. AMF colonized walnut roots, with <em>D</em>. <em>spurca</em> exhibiting the highest colonization rate and extraradical hyphal length. The responses of plant growth, root morphology, and leaf gas exchange to AMF inoculation varied, with <em>D</em>. <em>spurca</em> exerting greatest improvements. AMF inoculations significantly boosted juglone accumulation in roots (23−49%) and soil (90−148%), alongside a significant rise in β-glucosidase specific activity in roots (39−124%) and soil (27−54%). Notably, the increase in soil juglone was 2−3 times more than that in roots, whereas the induction of β-glucosidase activity was 2.3-4.6-fold higher in roots than in soil, with <em>D</em>. <em>spurca</em> triggering the most pronounced differences. A total of 18 <em>JrBGLUs</em> were identified, and their expression was differentially modulated by AMF colonization. Among these, 56−83% of <em>JrBGLU</em> members were consistently upregulated by AMF inoculation, with <em>JrBGLU2</em>‒<em>6</em>/<em>9</em>/<em>1</em><em>3</em><em>/</em><em>17</em>/<em>18</em> up-regulated by all AMF species. <em>D</em>. <em>spurca</em> caused the greatest number of <em>JrBGLU</em> genes to be upregulated, while <em>F</em>. <em>mosseae</em> eliciting the strongest upregulation of their expression levels. Significantly positive correlations were observed among core <em>JrBGLU</em> genes (<em>JrBGLU2-4/6/7/9/12</em>‒<em>14/16/18</em>), mycorrhiza, juglone, and β-glucosidase. This study provides the first evidence linking AMF-mediated activation of <em>JrBGLU</em> genes to promote juglone accumulation in walnuts. The highly effective <em>D</em>. <em>spurca</em>−walnut combination achieves a dual benefit: promoting plant productivity while simultaneously elevating juglone. These findings emphasize the necessity of context-specific application of AMF in walnut cultivation, considering both growth enhancement and potential allelopathic effects.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111161"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147284754","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":"Dianthus caryophyllus L.: Genetic improvement via LED bio-stimulation Enhances morphological, flowering parameters, enzyme activity, and molecular diversity","authors":"Iman M. El-Sayed ,&nbsp;Rasha A. El-Ziat ,&nbsp;Rasha G. Salim ,&nbsp;Walaa H. Salama ,&nbsp;Manar Hassan","doi":"10.1016/j.plaphy.2026.111158","DOIUrl":"10.1016/j.plaphy.2026.111158","url":null,"abstract":"<div><div>Carnation (<em>Dianthus caryophyllus</em> L.) is one of the floriculture industry's most popular, essential cut flowers, and potted plants. Light quantity and quality significantly affect metabolism and plant growth, and they interact with various factors, including environmental characteristics and significant plant behaviors. Correspondingly, red and blue light are essential signals to regulate growth and development, particularly photosynthesis and the activities of various antioxidant enzymes. The study's main objective was to examine the effect of red, blue, and mixed red-blue (RB) LEDs at different 0.5, 3, and 6 min irradiation intervals on plant growth and flowering morphological parameters, flowering quality, and chemical composition as well as to detect the genetic diversity of all treatments' irradiation compared to the control. The results revealed that the carnation irradiated with mixed (RB) irradiation for 3 min indicated the highest plant growth and flowering parameters compared to the control. However, red irradiation for 3 min gave the shortest number of days to early flowering (50 days). The burgundy color in flowers was improved in plants exposed to mixed RB for 0.5 and 3 min. Additionally, the mixed RB irradiation at 3 min treatment gave the maximum NPK uptake and protein, pigments, total phenolic, and flavonoid contents, and enhanced both enzymatic and non-enzymatic antioxidant activity among all treatment groups. Various LED wavelength treatments significantly induce genetic variability at the carnations' phenotypic and genotypic levels, with an average polymorphism level of SRAP molecular markers of 59%. Depending on SRAP and cluster analysis, the mixed RB irradiation for 3 min treatment had the lowest genetic similarity of 0.73 among the control and other treatments' plants. Our findings highlight the promising effect of mixed RB LED in ornamental plant cultivation due to its ability to enhance plant growth, flowering, and other characteristics.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111158"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147284795","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":"Integrated transcriptomic and metabolomic profiling reveals genotypic differences in UV-B radiation tolerance mechanisms in Elymus sibiricus L.","authors":"Fei Zhang ,&nbsp;Meixiu Chen ,&nbsp;Xuyi Liu ,&nbsp;Jinlong Ze ,&nbsp;Yaling Liu ,&nbsp;Kanghua Ma ,&nbsp;Yingzhu Li ,&nbsp;Daping Song ,&nbsp;Ming Sun ,&nbsp;Shiqie Bai ,&nbsp;Jiajun Yan","doi":"10.1016/j.plaphy.2026.111114","DOIUrl":"10.1016/j.plaphy.2026.111114","url":null,"abstract":"<div><div>Ultraviolet-B (UV-B) radiation in the Qinghai-Tibet Plateau (QTP) is a crucial environmental constraint affecting plant distribution and development. <em>E</em>. <em>sibiricus</em> is an important perennial grass species used for pasture establishment and grassland restoration in the QTP, whose molecular adaptation to UV-B stress remains underexplored. Herein, phenotypic physiology, transcriptomics, and metabolomics were integrated to systematically decipher UV-B response mechanisms in <em>E</em>. <em>sibiricus</em>. Exposure to 288 kJ/m² UV-B radiation in tolerant (SC020 2-A1, SC) and sensitive (XJ007 22-A5, XJ) <em>E</em>. <em>sibiricus</em> genotypes yielded 21,773 genes, with 5076 and 4541 genotype-specific differentially expressed genes (DEGs), respectively. Temporal profiling of the DEGs revealed 3792 and 6322 DEGs in SC, compared to 4826 and 10,890 DEGs in XJ under short- and long-term stress, respectively. Core findings demonstrated that MYB and WRKY transcription factors (TFs) mediated UV-B responses via phenylpropanoid metabolism and UVR8 signaling. In addition, 20 pivotal TFs, including EsMYB and EsbHLH, coordinated with 30 stress metabolites, such as corticosterone, to regulate the ascorbate and aldarate network, thereby activating 8 crucial pathways, including photosynthetic carbon fixation. Notably, heat shock proteins (HSP702 and HSP704) emerged as novel UV-B resistance components. These results provide molecular insights into UV-B adaptation of members of the Gramineae family and genetic resources for breeding UV-B radiation-resistant grass cultivars.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111114"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147356052","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":"TaHsfA2-11-TaZAT8 module negatively regulates salt tolerance in wheat","authors":"Runsi Qi ,&nbsp;Xiangzhao Meng ,&nbsp;Huaning Zhang ,&nbsp;Chunxia Li ,&nbsp;Zihui Liu ,&nbsp;Zhenyu Ma ,&nbsp;Shuonan Duan ,&nbsp;Zhonglin Shang ,&nbsp;Guoliang Li ,&nbsp;Xiulin Guo","doi":"10.1016/j.plaphy.2026.111183","DOIUrl":"10.1016/j.plaphy.2026.111183","url":null,"abstract":"<div><div>Plant heat shock transcription factor (Hsf) can directly activate the expression of various genes related to abiotic stress responses, thereby enhancing plant stress resistance, making them to be important target genes in modern molecular breeding. The wheat Hsf family has numerous members with complex functions and mechanisms, and a single gene often participates in multiple stress responses. Our previous studies reported that overexpression of the core subfamily member <em>TaHsfA2-11</em> (ACCESSION: KY774305) significantly improves plant thermotolerance, while its expression is significantly up-regulated by NaCl. Based on this, in this paper we generated transgenic plants of <em>Arabidopsis thaliana</em> and wheat and studied the salt resistance function of <em>TaHsfA2-11</em>. Phenotypic identification all revealed that both <em>TaHsfA2-11</em>-overexpressing <em>Arabidopsis</em> and wheat plants displayed more sensitive salt stress, with lower germination rate and cotyledons greening, and poorer growth vigor than the wild-type (WT). Moreover, <em>TaHsfA2-11</em> overexpressing <em>Arabidopsis</em> mutant <em>atHsfa2</em> (insensitive compared to the WT) also increased the sensitivity to salt stress. RNA-seq analysis results between the WT and overexpressed wheat revealed numerous differentially expressed genes, which were enriched in multiple biological processes, such as response to abiotic stimulus, reactive oxygen species, protein folding, protein complex oligomerization, <em>etc</em>, and pathways such as starch and sucrose metobolism, protein processing in endoplasmic reticulum, flavone and flavonol biosythesis, photosynthesis-antenna proteins<em>, etc</em>. RT-qPCR results indicated that majority of DEGs were upregulated by both salt and TaHsfA2-11. Among those, the Zinc finger protein 8 (<em>TaZAT8</em>), contains heat shock element (HSE) motif in the promotor, was prominently induced under NaCl treatment in <em>TaHsfA2-11-</em>OE wheat. Through experiments of electrophoretic mobility shift assay (EMSA) and dual luciferase reporter assay (DLR), we found that TaHsfA2-11 can bind to the HSE of TaZAT8 promoter and transcriptionally activate its expression. Overexpression of <em>TaZAT8</em> in <em>Arabidopsis thaliana</em> WT and mutant <em>athsfa2</em> markedly enhanced plant sensitivity to salt stress, displaying the similar salt resistance phenotypes with <em>TaHsfA</em>2-11-OE <em>Arabidopsis</em> and wheat. These findings indicated that TaHsfA2-11 perhaps regulates plant salt tolerance by modulating the expression of the negative regulator <em>TaZAT8</em> by mediating pathways such as photosynthesis, ROS accumulation, and flavonoid synthesis, <em>etc</em>. The results not only enrich the theory of crop salt tolerance regulation, expand the functional scope of the wheat HsfA2 subfamily genes, but also provide a key target gene for editing breeding aimed at enhancing salt tolerance of wheat.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111183"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147365814","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":"Pre-acclimation to low nitrogen enhances drought tolerance in Lolium perenne through integrated metabolic and transcriptional alterations","authors":"Hui Zuo ,&nbsp;Xinyue Xiong ,&nbsp;Yuqian Chen,&nbsp;Qianqian Guo","doi":"10.1016/j.plaphy.2026.111109","DOIUrl":"10.1016/j.plaphy.2026.111109","url":null,"abstract":"<div><div>Drought stress is a major constraint on the productivity of temperate forage grasses such as perennial ryegrass (<em>Lolium perenne</em>). While nitrogen management is widely employed in agronomic practice, its specific role in mediating drought adaptation strategies remains unclear. This study aimed to systematically characterize the response of perennial ryegrass to drought stress following low nitrogen pre-acclimation through integrated physiological and transcriptomic analyses during both stress and recovery phases. Our results demonstrated that drought severely impaired photosynthetic capacity and induced oxidative damage in non-acclimated plants, as evidenced by the significant reductions in net photosynthetic rate, stomatal conductance and PSII efficiency (<em>Fv</em>/<em>Fm</em>), alongside elevated malondialdehyde (MDA) levels and increased activities of key antioxidant enzymes (e.g., ascorbate peroxidase, peroxidase and catalase). In contrast, low nitrogen pre-acclimation effectively preserved photosynthetic performance under subsequent drought, mitigating declines in gas exchange parameters and maintaining PSII integrity. These pre-acclimated plants also exhibited reduced oxidative stress under drought and superior recovery capacity after rewatering. This enhanced drought tolerance was associated with fructan accumulation and tempered transcriptional responses. Low nitrogen pre-acclimation mitigated the drought-induced transcriptional upheaval, attenuated the activation of hormonal signaling pathways and <em>MAPK</em> cascades, significantly alleviated the downregulation of genes encoding photosynthetic apparatus, stabilized chlorophyll metabolism and optimized carbon-nitrogen balance. These findings reveal a nitrogen-mediated priming mechanism that enhances drought tolerance through integrated metabolic and transcriptional adjustments, providing new insights into the interaction between nutrient signaling and stress resistance, as well as potential strategies for enhancing plant tolerance under climate change.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111109"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146143364","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":"Comprehensive evaluation, morpho-physiological and transcriptional response involving the tolerance of Semi-wild soybean (Glycine gracilis) seedlings to nitrogen starvation","authors":"Siqi Hou ,&nbsp;Shixi Lu ,&nbsp;Yuechuan Hou ,&nbsp;Chunxiao Yu ,&nbsp;Jiarui Zhang ,&nbsp;Jichao Li ,&nbsp;Chunmei Zong ,&nbsp;Shuzhen Zhang ,&nbsp;Xiaodong Ding ,&nbsp;Jialei Xiao ,&nbsp;Qiang Li","doi":"10.1016/j.plaphy.2026.111120","DOIUrl":"10.1016/j.plaphy.2026.111120","url":null,"abstract":"<div><div>Nitrogen (N) limitation significantly constrains crop growth, yield and quality. Developing crop varieties with high N deficiency tolerance represents a critical strategy for reducing N fertilizer application and promoting sustainable agriculture. Semi-wild soybean offers valuable genetic resources for the improvement of soybean varieties. Nevertheless, the mechanisms underlying N deficiency tolerance remain poorly understood. In this study, we employed a comprehensive analytical approach—including Pearson's correlation analysis, principal component analysis, subordinate function analysis, and cluster analysis—to evaluate the N starvation tolerance of 50 semi-wild soybean varieties. Shoot fresh weight, root-shoot ratio, SPAD2 value and leaf nitrate content were identified as key indicators for assessing N starvation tolerance. The variety V03 was identified as the most N starvation-tolerant. Comparative physiological analyses revealed that V03 enhances tolerance to N deficiency by optimizing root architecture and sustaining the activity of nitrogen metabolism enzymes—such as nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT)—in root and leaf tissues. Transcriptomic analysis indicated that V03 exhibits a broader transcriptional response (with more N Starvation-induced DEGs) and functional reprogramming in root tissues, showing stronger enrichment in stress-responsive processes, regulatory functions, and plasma membrane-related terms as well as environmental information processing pathways. Furthermore, V03 displayed more pronounced changes in the expression of genes related to N transport, N assimilation and transcription factor (TF) compared to the N starvation-sensitive variety V46. This study provides a robust and comprehensive methodology for evaluating N deficiency tolerance in semi-wild soybean. Our findings offer new insights into the physiological adaptions and molecular regulatory network governing N uptake and metabolism, which may support future breeding efforts aimed at enhancing NUE in leguminous crops.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111120"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146158200","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":"Potassium application delays Zhebeimu (Fritillaria thunbergii Miq.) leaf senescence under shade","authors":"Honghai Zhu ,&nbsp;Huizhen Jin ,&nbsp;Dinghao Yang ,&nbsp;Leran Wang ,&nbsp;Yue Yin ,&nbsp;Wenjun Weng ,&nbsp;Shumin Wang ,&nbsp;Shipeng Jiang ,&nbsp;Qiang Yuan ,&nbsp;Guilan Duan ,&nbsp;Hui Wang ,&nbsp;Ning Sui","doi":"10.1016/j.plaphy.2026.111084","DOIUrl":"10.1016/j.plaphy.2026.111084","url":null,"abstract":"<div><div>Shade could improve the medicinal quality of Zhebeimu (<em>Fritillaria thunbergii</em> Miq.) bulb, but lead to decreased yield resulting from leaf senescence. Although potassium application can mitigate such yield loss by delaying leaf senescence, the underlying mechanism remains largely unknown. In this two-year field experiment, the widely cultivated variety ‘Zhebei 3’ was subjected to shade (around 50% shading) from the squaring stage, along with potassium application of 22.5 kg K₂O ha⁻¹. Shade treatment elevated the levels of senescence-inducing phytohormones [abscisic acid (ABA), salicylic acid (SA), jasmonic acid (JA), and 1-aminocyclopropanecarboxylic acid (ACC, the direct precursor of ethylene)], and reduced anti-senescence phytohormones [auxin (IAA) and cytokinin (CTK)]. It also suppressed the active oxygen scavenging system by lowering the activities of antioxidant enzymes [superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and glutathione peroxidase (GPX)] and the concentrations of non-enzymatic antioxidants [phenolics, flavonoids, flavones, and ascorbic acid (AsA)], leading to increased accumulation of O₂⁻ and malondialdehyde (MDA). Furthermore, shade impaired nitrogen assimilation via inhibiting the activities of nitrate reductase (NR), glutamine synthetase (GS), and glutamate synthase (GOGAT), thereby decreasing amino acid and soluble protein contents. These combined effects resulted in reduced chlorophyll contents and early leaf senescence. By contrast, potassium application increased IAA and CTK levels, enhanced activities of antioxidant enzymes (SOD, POD, CAT, and GPX) and contents of non-enzymatic antioxidant including flavonoids [(+)-gallocatechin, aromadendrin, kaempferol, quercetin, and myricetin] and flavones (kaempferol 3-sophorotrioside, astragalin, rutin, nictoflorin, quercetin 3-sophorotrioside, and isoquercitrin), and improved nitrogen assimilation. These changes collectively elevated chlorophyll contents and delayed shade-induced leaf senescence. Overall, this study broadened the understanding of the mechanism of potassium application in alleviating leaf senescence under shade.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111084"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146158203","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":"Transcriptomic plasticity through alternative splicing shapes salt stress responses in Korean sorghum","authors":"Hajung Lee ,&nbsp;Yuna Kang ,&nbsp;Changsoo Kim","doi":"10.1016/j.plaphy.2026.111060","DOIUrl":"10.1016/j.plaphy.2026.111060","url":null,"abstract":"<div><div>Sorghum (<em>Sorghum bicolor</em> L.) is a climate-resilient C4 crop that is widely cultivated in arid and saline-prone environments. Soil salinity is a major abiotic stress that adversely affects plant growth and productivity by inducing osmotic, ionic, and oxidative stress. Plants have evolved various molecular mechanisms to mitigate salt stress, including alternative splicing (AS), a post-transcriptional regulatory process that generates diverse transcript isoforms. Among AS event types, intron retention (IR) is the most prevalent in plants under abiotic stress conditions. In this study, we conducted a transcriptome analysis of three sorghum cultivars—Sodamchal, Nampungchal, and Hwanggeumchal—subjected to varying salt stress conditions over different time periods. Our findings revealed that intron retention accounted for more than 70 % of AS events across all comparisons. Importantly, several of these intron retention events were associated with salt stress–responsive genes, which support the notion that intron retention may function as a regulatory mechanism contributing to salt stress tolerance. Notably, in Hwanggeumchal and Nampungchal, the trehalose-phosphate phosphatase 6 (TPP6) gene and ATP-binding cassette (ABC) transporter G family member 42 gene exhibited AS-mediated expression changes, suggesting a potential link in salt tolerance. Under normal conditions, IR led to the expression of alternative isoforms that do not increase trehalose levels or ABC transporter function, whereas salt stress promoted normal splicing, which restored the functional biosynthesis pathways of both trehalose and ABC transporter. Given the established roles of trehalose and ABC transporters in stabilizing cellular structures, mitigating osmotic stress, and maintaining ion homeostasis, our results suggest that AS-mediated regulation of these pathways contributes to sorghum's adaptive response to salinity stress. These findings provide new insights into the molecular basis of sorghum's salt tolerance and highlight the importance of AS as a regulatory mechanism for improving stress resilience in crops.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111060"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122673","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":"CRISPR mediated inactivation of OsPLDβ1 phospholipase enhances drought tolerance by upregulating stress-related genes and antioxidant enzymes in rice","authors":"Sangeetha Karippadakam ,&nbsp;V. Mohan Murali Achary ,&nbsp;Dalia Vishnudasan ,&nbsp;Bipin Kumar G. Nair ,&nbsp;Hemangini Parmar ,&nbsp;Ganesan Prakash ,&nbsp;Malireddy K. Reddy","doi":"10.1016/j.plaphy.2026.111071","DOIUrl":"10.1016/j.plaphy.2026.111071","url":null,"abstract":"<div><div>Membrane lipids serve as precursors for intracellular signaling molecules, with the activation of phospholipases constituting an initial step in this process. Phospholipase D, a crucial family of enzymes that hydrolyze membrane lipids, plays a pivotal role in plant responses to stress. In this study, we used gene editing to disrupt the <em>OsPLDβ1</em> function in rice and evaluated its performance under drought conditions. The <em>Ospldβ1</em> mutants exhibited enhanced antioxidant enzyme activities, which led to reduced reactive oxygen species (ROS) accumulation, decreased seedling injury and mortality, and improved photosynthetic performance during drought stress. Additionally, the <em>Ospldβ1</em> mutants exhibited lower levels of drought stress indicators, including lipid peroxidation, electrolyte leakage, and chlorophyll loss. The <em>Ospldβ1</em> mutants showed lower ROS accumulation and better germination, and root development compared to the wild-type plants upon exposed to methyl viologen and mannitol. The expression other <em>PLD</em> family member genes (<em>OsPLDα,1 OsPLDα3</em>, <em>OsPLDδ1</em>, <em>OsPLDδ2</em>, <em>OsPLDδ3</em>) and stress responsive genes were upregulated in the <em>Ospldβ1</em> mutant lines during the drought stress condition. This study investigated the negative function of the <em>OsPLDβ1</em> gene in the drought tolerance mechanism. Deploying the <em>Ospldβ1</em> allele in breeding programs may facilitate the development of climate-resilient crop cultivars to address the climate change situation.</div></div>","PeriodicalId":20234,"journal":{"name":"Plant Physiology and Biochemistry","volume":"232 ","pages":"Article 111071"},"PeriodicalIF":5.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122676","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}