Environmental and Experimental Botany最新文献

{"title":"Morpho-physiological and ionic trait-based multi-index integrative salt tolerance assessment of rice genotypes from Pokkali and pan-Indian saline ecologies","authors":"T.V. Vineeth ,&nbsp;G.K. Krishna ,&nbsp;K.T. Ravikiran ,&nbsp;P.P. Gopinath ,&nbsp;Nitish Ranjan Prakash ,&nbsp;R.M. Francies ,&nbsp;K. Rajesh ,&nbsp;P.S. Philip ,&nbsp;V. Vighneswaran ,&nbsp;K. Bhrundha ,&nbsp;A.G. Kiran ,&nbsp;M.S. Parvathi","doi":"10.1016/j.envexpbot.2026.106316","DOIUrl":"10.1016/j.envexpbot.2026.106316","url":null,"abstract":"<div><div>Salinity stress imposes severe limitations on rice productivity, necessitating a mechanistic dissection of tolerance traits for robust identification of elite donors. We collected an extensive array of 335 genotypes from the inland and coastal saline tracts in India. The salinity tolerance potential of the diverse rice germplasm was evaluated at the seedling stage under moderate (8 dS m⁻¹) and high (12 dS m⁻¹) stress levels. A systematic trait-based screening was carried out using 13 morpho-physiological and 7 ionic parameters under control and two stress levels. Subsequently, salt tolerance indices (STI) calculated from the recorded traits were subjected to principal component analysis, which displayed near-identical correlation across both stress levels. It was observed that biomass traits clustered together and diverged from linear growth traits. Using the principal component traits thus identified, mean membership function values (MMFV) and Multi-trait genotype–ideotype distance index (MGIDI) were deployed for integrative tolerance ranking of genotypes. Regression analyses converged on root and shoot K⁺/Na⁺ ratios, and shoot dry weight as the most robust predictors of salt tolerance. Consequently, the developed ‘SalTol Reg’ model was reiterative in predicting a comprehensive salt tolerance index such as MMFV. Integration of multiple selection indices identified four previously unreported novel salt tolerant landraces, namely Neta, Arjunsal, Chovvaryan and Orthadiyan. These genotypes demonstrated superior biomass traits, tissue-specific Na⁺ exclusion and enhanced selective K⁺ translocation over Na⁺ to shoot tissues. Unraveling the molecular physiology underlying their tolerance will be a prudent step towards delivering promising salt tolerant donors.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"243 ","pages":"Article 106316"},"PeriodicalIF":4.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122701","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":"Jasmonate promotes tuber formation under elevated temperatures by repressing SP5G","authors":"Jinxiang Tang ,&nbsp;Yi Li ,&nbsp;Shijun Ma ,&nbsp;Xiaohang Su ,&nbsp;Jinsong Wu ,&nbsp;Lei Wang","doi":"10.1016/j.envexpbot.2026.106338","DOIUrl":"10.1016/j.envexpbot.2026.106338","url":null,"abstract":"<div><div>High temperatures strongly suppress potato tuber formation, and the role of the phytohormone jasmonate (JA) in this temperature response remains unclear. Here, we demonstrate that JA positively regulates potato thermotolerance during tuber formation. When tuber formation-stage potato plantlets were exposed to elevated temperatures (30/26 °C, day/night) for three weeks, wild-type plants incurred a 25% yield loss. In contrast, JA-deficient irAOC lines exhibited enhanced heat sensitivity (45% yield loss), while JA-elevated irCYP94B3s lines displayed robust heat resistance (only 5% yield loss). Reciprocal grafting confirmed aerial tissue-derived JA is sufficient for this thermotolerance. During tuber initiation, heat stress reduced leaf JA accumulation, which correlated with upregulated expression of the tuberization repressor <em>SP5G</em>. This implies JA may facilitate tuberization under elevated temperature, likely by suppressing <em>SP5G</em>. Transcriptomic analysis and electrophoretic mobility shift assays suggested JA regulates <em>SP5G</em> transcription via a heat-responsive MYB transcription factor in the JA signaling pathway. Our findings establish JA promotes potato tuber formation under elevated temperatures and identify CYP94B3 family genes as targets for breeding thermotolerant potato cultivars.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"243 ","pages":"Article 106338"},"PeriodicalIF":4.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147402636","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":"Going underground: The importance of soil heterogeneity in shaping plant productivity and responses to saline soils","authors":"Hannah M. Schneider ,&nbsp;Alon Ben-Gal ,&nbsp;Bliss Furtado ,&nbsp;Nuray Cicek ,&nbsp;Eleftheria Dalmaris ,&nbsp;Giulia Atzori ,&nbsp;Nadia Bazihizina","doi":"10.1016/j.envexpbot.2026.106321","DOIUrl":"10.1016/j.envexpbot.2026.106321","url":null,"abstract":"<div><div>Plants have to cope and respond to an ever-changing environment, including in soils. Their performance thus depends on their ability to perceive changes in the root zone and to adapt by altering resource allocation to growth, reproduction, or defense. With the majority of physiological and molecular research adopting a reductionist approach, which oversimplifies salinity as a single and uniform factor, conclusions drawn from these studies are likely to have underestimated the complex interactions that shape plant responses in field conditions. In this viewpoint, we argue that understanding root (and whole-plant) responses to soil heterogeneity, intended as the results of dynamic and multiple jointly acting abiotic stressors in saline environments, is central to salinity research. In particular, we introduce a conceptual agenda for studying roots under the dynamic and heterogeneous conditions found at the soil–root interface in saline soils, and its potential to provide new knowledge on how to deal with and adapt in a saltier world, with benefits for agriculture and natural resource management.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"243 ","pages":"Article 106321"},"PeriodicalIF":4.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122700","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":"Co-expression of GTP cyclohydrolase I and aminodeoxychorismate synthase from alfalfa improves folate accumulation and plant growth in Lotus corniculatus","authors":"Shan Feng ,&nbsp;Ya-Ping Lin ,&nbsp;Yi-Jun Cao ,&nbsp;Ai-Ke Bao","doi":"10.1016/j.envexpbot.2026.106335","DOIUrl":"10.1016/j.envexpbot.2026.106335","url":null,"abstract":"<div><div>Folate (vitamin B9) is an essential nutrient for livestock. However, natural folate levels in forage crops are often insufficient to meet livestock nutritional requirements. Metabolic engineering offers a promising solution by enhancing folate biosynthesis in plants. In this study, we engineered <em>Lotus corniculatus</em>, an important legume forage, to enhance folate biosynthesis by co-expressing GTP cyclohydrolase I and aminodeoxychorismate synthase genes <em>MsGCHI</em> and <em>MsADCS</em> from alfalfa (<em>Medicago sativa</em>). In T₀ transgenic plants grown under greenhouse conditions, total folate levels reached 2.1-fold higher in leaves and 1.7-fold higher in stems compared to WT, with similar trends in field trials, corresponding increases of 1.2-fold and 1.6-fold were observed. The elevated folate was accompanied by increased pools of biosynthetic precursors (pteridines and free p-ABA) and multiple folate derivatives, including 5-methyltetrahydrofolate (5-M-THF), 5,10-Methylenetetrahydrofolate (5,10-CH=THF), 5-Formyltetrahydrofolate (5-F-THF), tetrahydrofolate (THF)-related pool, and dihydrofolate (DHF). Furthermore, RT-qPCR analysis revealed that the co-expression of <em>MsGCHI</em> and <em>MsADCS</em> up-regulated the expression of key genes (<em>ADCL</em>, <em>HPPK/DHPS</em>, <em>DHFR</em>, <em>DHFS</em>, <em>DHNA</em>) involved in folate biosynthesis pathway of transgenic <em>L. corniculatus</em>, indicating a coordinated metabolic response to increased precursor availability. In addition to biochemical modifications, phenotypic characterization of transgenic plants revealed enhanced vegetative growth, including increased plant height, leaf area, branches, and biomass under greenhouse and/or field conditions. This study demonstrates the feasibility of folate biofortification in a forage legume and provides a proof of concept for linking enhanced folate metabolism with improved crop productivity in an agronomic context. These findings offer a foundational reference for future efforts toward developing biofortified forage as a potential nutritional supplementation strategy.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"243 ","pages":"Article 106335"},"PeriodicalIF":4.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147403270","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":"NLP7-HSFA2 module regulates acquired thermotolerance in Arabidopsis","authors":"Shiyun Zhao,&nbsp;Kexin Zhang,&nbsp;Hong Li","doi":"10.1016/j.envexpbot.2026.106320","DOIUrl":"10.1016/j.envexpbot.2026.106320","url":null,"abstract":"<div><div>Climate change, characterized by increasing global temperatures and a higher frequency of extreme heat events, is adversely affecting crop productivity and threatening global food security and agricultural sustainability. Heat Shock Transcription Factors (HSFAs) have been established as key regulators of thermotolerance in plants. Our previous studies have demonstrated that the transcription factor NIN-Like Protein 7 (NLP7) modulates the expression of HSFA3 in regulating basal thermotolerance. However, the involvement of NLP7 in acquired thermotolerance remains poorly understood. In this study, we demonstrate that NLP7 positively regulates plant acquired thermotolerance through directly binding to the HSFA2 promoter. These findings provide novel insights into the molecular mechanisms underlying heat adaptation, offering potential strategies for enhancing crop resilience in a warming climate.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"243 ","pages":"Article 106320"},"PeriodicalIF":4.7,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146187079","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":"Climate-mediated trade-offs between nutrient allocation and resorption efficiency in Phragmites australis along moisture gradients: A case study from an arid wetland in China","authors":"Jian Zhang ,&nbsp;Yixian Chen ,&nbsp;Asim Biswas ,&nbsp;Jiayi Zhang ,&nbsp;Yao Zhang ,&nbsp;Shuzhi Ji","doi":"10.1016/j.envexpbot.2025.106305","DOIUrl":"10.1016/j.envexpbot.2025.106305","url":null,"abstract":"<div><div>Arid wetland ecosystems face unprecedented challenges under accelerating climate change, yet the mechanistic understanding of how dominant species adapt their nutrient strategies remains critically limited. In this study, we use spatial moisture gradients as a proxy for long-term plant adaptation to differing water regimes, and interannual climate data to assess short-term modulation of nutrient strategies within these established gradients. Here, we present the comprehensive multi-year analysis of nutrient allocation and resorption trade-offs mediated by climatic variability in <em>Phragmites australis</em>, the keystone species of arid wetlands globally. Through three years (2021–2023) of field observations across spatial moisture gradients in China's Dunhuang wetland, we reveal fundamental trade-offs between belowground nutrient allocation and aboveground resorption efficiency that determine ecosystem functioning. Our results demonstrate that interannual precipitation variability regulates nutrient resorption strategies along spatial moisture gradients, while simultaneously exerting indirect effects through leaf N:P ratios and soil available phosphorus modifications. Specifically, leaf nitrogen resorption efficiency decreased significantly with increasing soil moisture across sites (from 75 % in low moisture to 66 % in high moisture), while phosphorus allocation to rhizomes increased under elevated moisture conditions. Structural equation modelling revealed that precipitation influences these responses through dual pathways: direct physiological effects and indirect modifications of leaf nitrogen-to-phosphorus ratios and soil available phosphorus. Critically, we discovered a negative correlation between rhizome-to-leaf nutrient ratios and leaf resorption efficiency (path coefficient = −0.53 and −0.27 for nitrogen and phosphorus, respectively), indicating that <em>Phragmites australis</em> employs contrasting nutrient conservation strategies depending on resource availability. Under water-limited conditions, plants prioritize leaf nutrient resorption, while under favourable moisture conditions, they enhance belowground nutrient allocation. These findings provide a conceptual framework for predicting plant nutrient responses to interannual climate variability as expressed through spatial moisture conditions in arid wetland ecosystems and offer insights that may inform wetland conservation strategies in water-limited regions.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"242 ","pages":"Article 106305"},"PeriodicalIF":4.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145969410","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":"Silicon nanoparticles mitigate cadmium toxicity in rice by modulating root development and exudate dynamics","authors":"Md Tofail Hosain ,&nbsp;Md Imran Ullah Sarkar ,&nbsp;Shamim Mia ,&nbsp;Md Mokhlesur Rahman ,&nbsp;Ravi Naidu ,&nbsp;Mohammad Mahmudur Rahman","doi":"10.1016/j.envexpbot.2026.106318","DOIUrl":"10.1016/j.envexpbot.2026.106318","url":null,"abstract":"<div><div>Cadmium (Cd) contamination severely hampers rice (<em>Oryza sativa</em> L.) growth by disrupting root development, nutrient uptake, and exudation processes, posing a major risk to food security. This study investigated the role of silicon nanoparticle (SiNP) on root architecture and root exudation dynamics in rice grown hydroponically under two levels of Cd (10 and 20 μM). Cadmium markedly impaired root development, as evidenced by significant reductions in root length (8.94 % and 17.93 %), surface area (15 % and 31.42 %), diameter (15.78 % and 28.94 %), volume (8.15 % and 25.54 %), biomass (31.19 % and 40.36 %), and water uptake efficiency (11.94 % and 28.05 %) at 10 and 20 μM, respectively, while concurrently increasing root branching. Co-application of SiNP mitigated these effects, enhancing root biomass (28.00 % and 32.30 %) and restoring water uptake (14.31 % and 11.91 %) relative to Cd-only treatments. Cadmium stress inhibited antioxidant enzymes (APX, CAT, SOD, POD) and increased oxidative damage (MDA, electrolyte leakage). SiNP co-application substantially mitigated Cd-induced oxidative stress in rice roots by restoring APX 17.8 and 39.4 %, CAT 37.0 and 70 %, SOD by 7.25 and 15.61 % and POD by 14.59 and 38.00 %, respectively, with both levels of Cd stress, while reduced MDA and electrolyte leakage by 27.7 % and 29.6 %, respectively, with the highest levels of Cd stress. Cadmium stress also significantly altered the profile of root exudates, decreasing oxalic acid (Cd₁₀: 22.03 %; Cd₂₀: 32.60 %) and citric acid (Cd₁₀: 38.23 %; Cd₂₀: 49.67 %) while increasing malic acid production (Cd₁₀: 11.48 %; Cd₂₀: 17.84 %). SiNP supplementation reversed these shifts by elevating oxalic (Cd₂₀: 17.43 %) and citric (Cd₂₀: 24.29 %) acids, suppressing malic acid release (Cd₁₀: 21.39 %; Cd₂₀: 26.83 %), and overall enhancing total organic acid secretion, thereby contributing to rhizosphere acidification. Over time, SiNP significantly lowered Cd bioavailability in the nutrient solution, likely via Si–Cd complexation and organic acid-mediated chelation. At the cellular scale, SiNP supplementation reduced Cd accumulation in both the cell wall and symplast, indicating restricted Cd uptake and transport. Moreover, Cd stress substantially increased total organic carbon (TOC) (Cd₁₀: 32.28 % and Cd₂₀: 58.13 %) and total nitrogen (TN) (Cd₁₀: 4.25 % and Cd₂₀: 27.71 %) in rhizosphere exudates, SiNP co-treatment also moderated these elevations and concurrently preserved cellular ultrastructure. Therefore, SiNP mitigated Cd toxicity by improving root architecture, modulating exudation, and reducing Cd bioavailability and uptake. These findings demonstrate the potential of SiNPs as a sustainable nanotechnology-based strategy for reducing Cd accumulation in rice and safeguarding food quality.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"242 ","pages":"Article 106318"},"PeriodicalIF":4.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184678","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":"Cysteine and glutathione improve mercury tolerance in rice by modulating cell wall binding, transport, and detoxification pathways","authors":"Yeon-Ok Kim ,&nbsp;Dream Kim ,&nbsp;Mahpara Safdar ,&nbsp;Jangho Kim","doi":"10.1016/j.envexpbot.2026.106312","DOIUrl":"10.1016/j.envexpbot.2026.106312","url":null,"abstract":"<div><div>Mercury (Hg), a highly toxic element, poses significant risks to plant growth and human health. This study investigated the mechanisms of Hg accumulation and tolerance by exogenous cysteine (Cys) and glutathione (GSH) in rice. Here, we showed that exogenous Cys and GSH significantly enhanced Hg tolerance in rice but exhibited contrasting effects on Hg accumulation. Exogenous Cys significantly increased Hg accumulation in rice roots, primarily in the cell wall, while exogenous GSH decreased root Hg accumulation. Exogenous Cys significantly increased the expression of cell wall biosynthesis genes, particularly those involved in lignin synthesis, resulting in greater lignin accumulation in epidermis, exodermis, and stele, which correlated with increased Hg binding to the cell wall. In addition, exogenous Cys significantly upregulated several ABC transporters, particularly OsABCGs and OsABCCs, suggesting their possible involvement in Hg transport and vacuolar sequestration. In the process of cellular Hg detoxification, GSH upregulated aquaporin to maintain membrane function and water balance, Cys primarily activated peroxidase-mediated H₂O₂ scavenging. Taken together, these findings highlight novel candidate genes involved in Hg cell wall binding, transport, and detoxification, regulated by Cys and GSH, offering insights for enhancing our understanding of the molecular mechanisms underlying Hg accumulation and tolerance. Furthermore, this study provides new insights into thiol-mediated Hg tolerance and offers potential strategies for reducing Hg accumulation in crops.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"242 ","pages":"Article 106312"},"PeriodicalIF":4.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145976389","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":"Identification and characterization of circular RNAs involved in cadmium response in Malus hupehensis","authors":"Baozhen Sun ,&nbsp;Bing Chen ,&nbsp;Jianfei Song ,&nbsp;Weiwei Zhang ,&nbsp;Hongqiang Yang","doi":"10.1016/j.envexpbot.2026.106314","DOIUrl":"10.1016/j.envexpbot.2026.106314","url":null,"abstract":"<div><div>Cadmium (Cd) is a non-essential heavy metal that is highly toxic to plants. While numerous regulatory factors that contribute to Cd responses in plants have been identified, few studies focus on circular RNAs (circRNAs). CircRNAs are endogenous RNA molecules that are involved in plant growth, development, and stress resistance. However, the potential involvement of circRNAs in plant responses to Cd remains largely unexplored. High-throughput sequencing identified 401 high-confidence circRNAs from the roots of <em>Malus hupehensis</em> seedlings subjected to Cd stress. We identified 140 differentially expressed circRNAs (DECs), of which 55 were explicitly differentially expressed in more than one pairwise comparison. Notably, 37 of these DECs contained 47 binding sites for 23 miRNAs that have the potential to regulate the expression of several Cd transporters, including <em>MhNRAMP1</em>, <em>MhHMA1</em>, <em>MhZIP1</em>, and <em>MhABCG25</em>, as well as Cd-related transcription factors, through circRNA-miRNA-mRNA regulatory networks. Furthermore, we identified a Cd-induced circRNA, <em>Mh-circCWF19</em>, negatively regulates Cd tolerance in <em>Malus hupehensis</em> seedlings and apple calli. Our findings uncovered the critical roles of plant circRNA in Cd toxicity.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"242 ","pages":"Article 106314"},"PeriodicalIF":4.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075309","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":"DNA hypomethylation induced by drought preconditioning improved physiological responses and promoted tiller growth of perennial ryegrass","authors":"Lili Zhuang ,&nbsp;Yunjia Ding ,&nbsp;Nan Yang ,&nbsp;Luyao Wang ,&nbsp;Zhimin Yang","doi":"10.1016/j.envexpbot.2026.106317","DOIUrl":"10.1016/j.envexpbot.2026.106317","url":null,"abstract":"<div><div>Previous studies have shown that perennial ryegrass exhibits superior performance under drought preconditioning (DP) compared to continuous drought stress (DR) or even well-watered conditions (WW), however, the underlying mechanisms remain unclear. This study aims to elucidate if changes in DNA methylation could be the mechanism behind preconditioning, particularly studying its contribution to plant physiological responses and tiller growth. Dynamic alterations in DNA methylation levels in the crowns of perennial ryegrass were detected at 14, 17, 30, 33, and 44 days under WW, DP, and DR by the methylation-sensitive amplification polymorphism (MSAP) method. DNA methylation level was significantly elevated after 14 days of drought stress. Conversely, DP treatment induced DNA hypomethylation, with MSAP% at DP₃₀, DP₃₃, and DP₄₄ being lower than DR and comparable to WW. Supplementing S-adenosylmethionine (SAM), a methyl group donor, counteracted the beneficial effects of DP, evidenced by reduced chlorophyll content, aboveground biomass, net photosynthesis rate (Pn), and tiller number in DPS (DP + SAM) compared to DP. In contrast, applying 5-azacytidine (5-azaC), a DNA methylation inhibitor, mimicked the DP effect, increasing leaf relative water content, aboveground biomass, Pn, and tiller number while reducing electrolyte leakage rate. Relative expression levels of DNA methylase and demethylase genes under SAM and 5-azaC treatments supported the dynamic changes of DNA methylation level in those plants. Meanwhile, expression levels of methylation genes were significantly correlated with the physiological parameters. This study provides the first evidence for the dynamic role of DNA methylation regulating perennial ryegrass physiological and tiller growth underlying the drought preconditioning process.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"242 ","pages":"Article 106317"},"PeriodicalIF":4.7,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075307","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}