Environmental and Experimental Botany最新文献

{"title":"Biochar amendment enhances water use efficiency in alfalfa (Medicago sativa L.) under partial root-zone drying irrigation by modulating abscisic acid signaling and photosynthetic performance","authors":"Shangzhi Zhong ,&nbsp;Xiang Zhang ,&nbsp;Pengxin Hou ,&nbsp;Jianghan Ouyang ,&nbsp;Tovohery Rakotoson ,&nbsp;Congcong Zheng ,&nbsp;Qibo Tao ,&nbsp;Juan Sun","doi":"10.1016/j.envexpbot.2025.106244","DOIUrl":"10.1016/j.envexpbot.2025.106244","url":null,"abstract":"<div><div>Deficit irrigation can potentially increase plant water use efficiency by regulating stomatal morphology and photosynthetic physiology, whereas the combined effects of biochar amendment and deficit irrigation on alfalfa growth and leaf physiology remain largely unknown in salt-affected soil. A split-root pot experiment was implemented to investigate the effect of biochar amendments (WSB: wheat straw biochar; CSB: corn straw biochar) and irrigation regimes (FI: full irrigation; DI: deficit irrigation, 70 % of FI on the entire root zone; PRDI: partial root-zone drying irrigation, only irrigating half of the root zone with soil water content maintained at the same level as that under DI) on the leaf morpho-physiological traits and water use efficiency of alfalfa (<em>Medicago sativa</em> L.). DI and PRDI exhibited a similar trend, with both leading to a significant reduction in stomatal conductance (<em>g</em>_s), carbon isotope discrimination (Δ¹³C_leaf), and net CO₂ assimilation rate (<em>A</em>) by altering stomatal traits and elevating leaf abscisic acid concentration ([ABA]_leaf), resulting in lower biomass accumulation. In contrast, biochar amendment of WSB and CSB significantly improved soil water-holding capacity, root water uptake and leaf water status, resulting in lower [ABA]_leaf and enhanced stomatal density (SD), stomatal size (SS) and Δ¹³C_leaf. Notably, PRDI combined with biochar amendment substantially enhanced leaf intrinsic WUE (<em>A</em>/<em>g</em>_s) and long-term WUE indicated by lower Δ¹³C_leaf, thereby increasing plant-scale WUE (WUE_plant) by 39–56 % compared to non-biochar-amended under PRDI treatment. Overall, co-application of biochar amendment and deficit irrigation facilitates more efficient and ecologically sustainable alfalfa management in salt-affected soil. Future studies should investigate long-term effects, underlying mechanisms, and large-scale applicability across diverse environmental contexts.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106244"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155219","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":"High boron in irrigation water mitigates drought stress effects on 'Carrizo' citrange seedlings","authors":"M. Tasa ,&nbsp;M. González-Guzmán ,&nbsp;V. Arbona ,&nbsp;J.G. Pérez-Pérez","doi":"10.1016/j.envexpbot.2025.106228","DOIUrl":"10.1016/j.envexpbot.2025.106228","url":null,"abstract":"<div><div>Cultivating citrus in semi-arid areas exposes them to drought periods and sometimes irrigation with non-conventional water sources (e.g. reclaimed water and desalinated seawater) containing high boron (B) concentration. This study aims to determine how high B influences plant water relations and water transport in well-watered (WW) and drought-stressed (DS) ‘Carrizo’ citrange [<em>Citrus sinensis</em> (L.) Osb. × <em>Poncirus trifoliata</em> L.] seedlings during a stress period and after rewatering. Seedlings were well-watered with control B (0.11 mg·L⁻¹) or high B concentration (5 mg·L⁻¹) for 29 days. Then irrigation was withheld from half the plants for 7 days (drought-stressed, DS), followed by a 10-day re-irrigation period using control B. High B irrigation increased endogenous B accumulation, without reaching toxic levels as chlorophyll fluorescence parameters remained unaltered and plant water status was unaffected. However, partial stomatal closure mediated by a 1.8-fold increase in foliar ABA accumulation decreased transpiration and photosynthesis. Under drought stress, plants irrigated with high B concentration better maintained their leaf water status, with leaf water potential decreasing by only 0.9 MPa compared to 1.8 MPa decrease in Control B-DS plants relative to their respective well-watered plants. Thus, high B enhanced drought tolerance through ABA-mediated stomatal regulation, allowing more conservative water use during drought. Plant water status of high B plants recovered faster and more completely than control B plants, which experienced greater drought-induced damage.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106228"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144912570","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":"Position-specific isotope labelling gives new insights into chiral monoterpene synthesis of Norway spruce (Picea abies L.)","authors":"L. Erik Daber ,&nbsp;Philipp Nolte ,&nbsp;Jürgen Kreuzwieser ,&nbsp;Mirjam Meischner ,&nbsp;Jonathan Williams ,&nbsp;Christiane Werner","doi":"10.1016/j.envexpbot.2025.106238","DOIUrl":"10.1016/j.envexpbot.2025.106238","url":null,"abstract":"<div><div>Chiral forms of monoterpenes and their enantiomeric composition are of ecological significance, e.g. for plant-insect interactions. However, biosynthetic pathways and drought-induced changes of enantiomeric monoterpene emissions are barely understood. We analyzed, for the first time, drought effects on the enantiomeric composition of <em>de novo</em> vs. storage emitted monoterpenes from Norway spruce saplings by position-specific ¹³C-pyruvate (¹³C2- and ¹³C1-labelled) feeding and ¹³CO₂ fumigation. Drought reduced total monoterpene emissions already during its early stages, strongly linked to net photosynthesis, and lead to a decline in <em>de novo</em> synthesis of monoterpenes. However, it unevenly affected chiral monoterpenes, leading to compositional changes of emissions with increasing drought. At the onset of drought, the (-)-enantiomers of limonene, β-phellandrene, α- and β-pinene were emitted at higher rates than the (+)-enantiomers. Our results suggest that (-)-enantiomers were emitted mainly from storage pools while emissions of (+)-enantiomers rather depended on <em>de novo</em> biosynthesis. Even though biosynthesis of different monoterpenes derives from the same precursor pool, isotopic label incorporation revealed three groups among monoterpenes: storage derived, dominantly labelled via ¹³C2-pyruvate, and dominantly labelled via ¹³CO₂-fumigation. Our results contribute to a growing amount of evidence of high flexibility in metabolic pathways of monoterpene biosynthesis in plant cells.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106238"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096345","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 development of biological soil crusts reshapes the strategies of non-structural carbohydrates in response to nitrogen deposition","authors":"Mingming Wang ,&nbsp;Zihan Kan ,&nbsp;Tingting Hui ,&nbsp;Boyi Song ,&nbsp;Huiliang Liu ,&nbsp;Benfeng Yin ,&nbsp;Ye Tao ,&nbsp;Xiaoying Rong ,&nbsp;Wei Hang ,&nbsp;Yuanming Zhang ,&nbsp;Xiaobing Zhou","doi":"10.1016/j.envexpbot.2025.106241","DOIUrl":"10.1016/j.envexpbot.2025.106241","url":null,"abstract":"<div><div>Non-structural carbohydrates (NSC) are critical indicators of the carbon acquisition and consumption balance in vascular plants, and are equally important for biological soil crusts (BSCs), which serve as significant carbon sinks in arid regions. Nitrogen (N) deposition significantly alters NSC storage by affecting plant growth, photosynthesis, and the carbon-to-nitrogen ratio. However, the response of NSC to N deposition may vary across different developmental stages of BSCs due to differences in physiological structures and soil properties. We conducted a long-term field N addition experiment (2010–2021) in the Gurbantunggut Desert, with N rates from 0 to 3 g m⁻² yr⁻¹ and a 2:1 NH₄⁺-N to NO₃⁻-N ratio, to examine the effects of N on NSC and their components (fructose, sucrose, soluble sugars, and starch) in three BSC types: cyanobacterial, lichen, and moss crusts. Our results revealed that the development of BSCs from cyanobacterial to lichen and moss crusts significantly alters NSC allocation, with an increasing ratio of soluble sugars to starch (0.24–1–1.68). As N added levels rise, NSC content in all three BSC types exhibits a nonlinear trend, characterized by low promotion and high inhibition, with distinct threshold points (N1.5-N0.5-N0.5). This phenomenon arises from shifts in the NSC driving factors under N addition: transitioning from soil nutrient dependence (cyanobacteria) to regulation by plant antioxidant enzyme activity (lichen), and ultimately to a more complex physiological regulation involving photosynthetic pigments and antioxidant enzyme activities (Moss). This study reveals the transition of BSCs from “environmental adapters” to “ecological regulators” throughout their successional stages. These findings provide new insights into the C metabolism of BSCs and have important implications for ecological restoration in N-impacted arid regions.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106241"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096344","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":"Root nodule presence alters the dynamics of photosynthate translocation under varying soil moisture conditions","authors":"Yuta Miyoshi ,&nbsp;Shota Teramoto ,&nbsp;Fumiyuki Soma ,&nbsp;Yong-Gen Yin ,&nbsp;Nobuo Suzui ,&nbsp;Yusaku Noda ,&nbsp;Kazuyuki Enomoto ,&nbsp;Naoki Kawachi ,&nbsp;Joseph Peller ,&nbsp;Eiji Yoshida ,&nbsp;Hideaki Tashima ,&nbsp;Taiga Yamaya ,&nbsp;Yusaku Uga","doi":"10.1016/j.envexpbot.2025.106235","DOIUrl":"10.1016/j.envexpbot.2025.106235","url":null,"abstract":"<div><div>This study investigated the dynamics of ¹¹C-labeled photosynthate translocation in nodulated and non-nodulated soybean plants across three time windows: during the low water condition, and at 0–3 h and 4–7 h after the recover water content. Advanced imaging techniques, including positron emission tomography (PET) and X-ray computed tomography (X-ray CT), enabled three-dimensional visualization of root structures and carbon allocation patterns. Under low water condition, nodulated soybeans prioritized carbon translocation to taproots and nodules. Using logistic modeling of ¹¹C accumulation, <em>Vmax</em> (steepest slope; maximum translocation rate) and <em>Kmax</em> (asymptote; accumulation capacity) were calculated. In nodulated plants, <em>Vmax</em> at lateral root tips increased by 56 % during 0–3 h after rewatering relative to the low-water condition; during 4–7 h, <em>Vmax</em> and <em>Kmax</em> at middle-layer nodules increased by 55 % and 49 %, respectively. Collectively, these results indicate a temporal reorganization of sink activity after rewatering—from lateral root tips early to middle-layer nodules later. These observations are consistent with a role for nodules as prominent sinks that may facilitate the redistribution of photosynthates after rewatering, whereas non-nodulated plants showed decreases in <em>Vmax</em> and <em>Kmax</em> across root regions under low-water conditions and exhibited little recovery during 0–3 and 4–7 h after rewatering. These patterns are consistent with a role for nodules in facilitating the reactivation and redistribution of carbon sinks under changing water availability. This study clarifies how water status modulates belowground carbon allocation in soybean and provides a basis for evaluating nodule-associated sink behavior under fluctuating moisture. These insights may inform crop management and guide breeding strategies aimed at improving resilience to water variability.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106235"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145096343","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":"Seasonal changes rather than competition drive inorganic and organic nitrogen acquisition and internal allocation in temperate trees","authors":"Robert Reuter,&nbsp;Judy Simon","doi":"10.1016/j.envexpbot.2025.106227","DOIUrl":"10.1016/j.envexpbot.2025.106227","url":null,"abstract":"<div><div>For trees, soil nitrogen (N) acquisition and its internal allocation to different tissues are driven by species’ properties (e.g. growth rate, nutrient demand), the interactions among tree species, and their abiotic environment. Over the growing season, abiotic changes in, e.g. temperature and rainfall affect biogeochemical N cycling as well as N allocation and remobilisation processes in trees. We studied the influence of seasonality and developmental variation in woody seedlings, focussing on tree-tree interactions. We investigated the interaction effects among seven temperate European tree species on their inorganic and organic net N uptake capacity, internal allocation of N to metabolically active and storage tissues, and morphological traits at four leaf developmental stages over the growing season (i.e. before bud break, after leaf development, before / after leaf senescence). Seedlings of seven temperate European tree species were grown in mesocosms under natural forest conditions in intra- or interspecific competition. At the beginning of the growing season, organic N was favoured over inorganic N, whereas in autumn all N sources were taken up equally. Within species, N uptake and internal allocation generally varied over the growing season, except for N acquisition in <em>Carpinus</em>. Among tree species, the differences in N uptake and allocation were more related to species-specific morphological and physiological root traits, rather than functional properties. The outcome of the interactions was not generally affected within a tree community over the growing season but depended on the individual species. Thus, seasonal variation and species-specific properties should be considered for mixed species forests.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106227"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144912569","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":"Comparative analysis of photosynthetic heat tolerance mechanisms in select Rubus subgenus Idaeobataus species using a numerical modeling and partitioning approach","authors":"Fa-Pin Chen,&nbsp;Wei-Chao Cheng,&nbsp;Ching-Lung Lee,&nbsp;Kuo-Tan Li","doi":"10.1016/j.envexpbot.2025.106247","DOIUrl":"10.1016/j.envexpbot.2025.106247","url":null,"abstract":"<div><div>The cultivated red raspberry (<em>Rubus idaeus</em>) in the genus <em>Rubus</em> subg. <em>Idaeobatus</em> is an economically valued berry crop but its cultivation has been limited by heat in the warm climate regions. Many species in the same subgenus are native to the subtropics and have been considered as potential germplasms for improving heat tolerance of raspberry cultivars. However, their photosynthetic responses to high temperatures and adaptation mechanisms have not been comprehensively exploited. In this study, leaf gas exchange characters of raspberry ‘Summer Festival’ and three subtropical native species, <em>R. fraxinifolius</em>, <em>R. rosifolius,</em> and <em>R. croceacanthus</em>, were mathematically analyzed. Net photosynthetic assimilation rate (<em>A</em>) and chlorophyll fluorescence against photosynthetic photon flux density (PPFD) and internal carbohydrate concentration (<em>C</em>_i) were measured at 25, 30, and 35℃. Data from the measurements were fitted to modified Farquar, von Cammerer and Berry (FvCB) models and key photosynthetic variables were extracted. Inter- and intra- species differences in <em>A</em> (% Δ<em>A</em>) were quantified by partitioning the total difference into individual and categorized variables using a numerical integration method. The results showed that light saturated <em>A</em> and transpiration (<em>E</em>) of <em>R. idaeus</em> were suppressed at 35℃ while both in the subtropical native species sustained or elevated at the high temperature of 30 and 35℃. The two key photosynthetic biochemical variables, maximum carboxylation rate (<em>V</em>_cmax) and maximum electron transport rate (<em>J</em>_max), were both increased at high temperatures in all studied taxa. Nevertheless, the superior <em>A</em> of the subtropical species was mainly contributed by the improved diffusional factors, i.e., stomatal conductance (<em>g</em>_sc) and mesophyll conductance (<em>g</em>_m), in response to elevated temperatures. This study demonstrated that the select subtropical native species better adapt to heat than the cultivated raspberry by maintaining leaf temperature low and photosynthetic efficiency high through consistent <em>g</em>_sc and improved <em>g</em>_m. The information suggested that for breeding programs targeting on heat tolerance, screening candidate genotypes with photosynthetic diffusional factors should be more efficient than evaluating biochemical factors. The results also provide useful references for raspberry industry to develop cultivation strategies to alleviate the impact from intensifying climate change situations.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106247"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217021","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":"Differences in cold-induced sweetening among potato cultivars and its formation mechanism","authors":"Zhaoyan Lv ,&nbsp;Tingting Liu ,&nbsp;Yue Huang ,&nbsp;Tao Zeng,&nbsp;Mengjie Zhang,&nbsp;Jianming Li,&nbsp;Lijie Zhang,&nbsp;Hualan Hou,&nbsp;Xiaobiao Zhu","doi":"10.1016/j.envexpbot.2025.106253","DOIUrl":"10.1016/j.envexpbot.2025.106253","url":null,"abstract":"<div><div>Frying enhances potato value addition. However, potato tubers produce reducing sugars during cold storage, causing cold-induced sweetening (CIS), which severely affects fried products quality. Therefore, exploring the mechanism of resistance to CIS is very important. In this study, the tubers of 10 local widely planted and processing-type cultivars were subjected to cold treatment at 4°C for 0, 2, 4 and 8 weeks, and sugar contents, enzymes activities, starch–sugar metabolism genes and fried chips' color were analyzed. The gene encoding vacuolar acid invertase (<em>VInv</em>) expression peaked at 2 weeks in 70 % of the cultivars; <em>VInv</em> and sucrose phosphate synthase gene (<em>SPS</em>) generally rose then fell with prolonged treatment. The acid invertase (AI) and granule-bound starch synthase (GBSS) activities increased overall, while the sucrose phosphate synthase (SPS) and sucrose synthase (SuSy) activities increased then decreased. After 4 weeks, 50 % of cultivars had significantly higher reducing sugars, darker chips and varied CIS phenotypes. Correlation analysis revealed that <em>VInv</em>-<em>SPS</em> expression was positively correlated in 8 cultivars. AI activity significant positively correlated with the reducing sugar content and the CIS phenotype in 70 % of them. SPS/SuSy activity positively correlated with sucrose in 70 %/60 % of cultivars, and the GBSS activity positively correlated with sucrose, reducing sugars, and CIS phenotype, respectively in over 70 % of them. Atlantic, Zhongshu 3, Huangbaoshi, Zaodabai, and Zhongshu 5 showed different CIS resistance degrees. These results laid the foundation for further studying biological functions and molecular mechanisms of genes regulating potato CIS.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106253"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145320916","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":"Integrative transcriptomic and metabolomic analyses reveal crucial roles of phenylpropanoid-derived coumarin biosynthesis in the responses of peanut to iron deficiency","authors":"Jiaqi Ma,&nbsp;Rui Liu,&nbsp;Ziling Zhou,&nbsp;Qiyue Zhang,&nbsp;Gangrong Shi","doi":"10.1016/j.envexpbot.2025.106250","DOIUrl":"10.1016/j.envexpbot.2025.106250","url":null,"abstract":"<div><div>Iron (Fe) deficiency severely limits peanut productivity, particularly in calcareous soils. This study integrated transcriptomic and metabolomic analyses to elucidate molecular mechanisms underlying Fe-deficiency responses in two peanut cultivars: Silihong (Fe-efficient) and Fenghua 1 (Fe-inefficient). Under Fe deficiency, both cultivars exhibited leaf chlorosis and reduced chlorophyll content, with Fenghua 1 showing greater sensitivity. Fe deficiency triggered extensive metabolic reprogramming, preferentially enhancing phenylpropanoid-derived coumarin biosynthesis while suppressing lignin and flavonoid pathways. Key genes, including <em>PAL1</em>, <em>4CL1</em>, <em>CCoAOMT</em>, <em>CSE</em>, <em>CYP98A2</em>, <em>HCT</em>, <em>F6′H1</em>, <em>S8H</em>, and <em>CYP82C4</em>, were upregulated, promoting the accumulation of Fe-mobilizing coumarins (scopoletin, fraxetin, esculetin). The efficient cultivar Silihong displayed stronger induction of coumarin synthesis genes, higher coumarin exudation, and greater suppression of competing pathways than Fenghua 1. Weighted gene co-expression network analysis identified hub genes (<em>FIT</em>, <em>MYB72</em>, <em>IRT1</em>, and <em>FRO2</em>) co-expressed with coumarin biosynthesis genes (<em>CCoAOMT</em>, <em>F6′H1</em>, <em>S8H</em>, and <em>CYP82C4</em>), suggesting an evolutionarily conserved FIT–MYB72 regulatory module for Fe acquisition. Additionally, <em>PDR3</em> homologs implicated in coumarin secretion were significantly induced. These findings highlight coumarin-mediated Fe mobilization as a critical adaptive strategy in peanuts and provide genetic targets for breeding Fe-efficient cultivars.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106250"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217022","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":"Citric and malic acids influence uranium(VI) uptake into Brassica napus in hydroponic culture by affecting solubility and speciation","authors":"Warren A. John ,&nbsp;Robin Steudtner ,&nbsp;Jenny Jessat ,&nbsp;René Hübner ,&nbsp;Frank Bok ,&nbsp;Susanne Sachs","doi":"10.1016/j.envexpbot.2025.106248","DOIUrl":"10.1016/j.envexpbot.2025.106248","url":null,"abstract":"<div><div>The migration of uranium (U) in soil and its uptake into plants is known to be affected by many factors, one of which is the presence of organic acids, e.g. as root exudates of plants, in soil. To date, the influence of the organic acids on mobilization and uptake is known but very little has been elucidated about the mechanisms involved. In this study, using hydroponic cultivations of <em>Brassica napus</em> and combining the analytical methods time-resolved laser-induced fluorescence spectroscopy and transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy, we explored the influence of two organic acids on the U speciation in hydroponic culture medium and the bioassociation of U to <em>B. napus</em> plants. Both citric acid and malic acid significantly increased the solubility of U in the hydroponic solution by forming U(VI) citrate and U(VI) malate complexes compared to control samples without the addition of the organic acids, in which a significant amount of U precipitated. By using this multi-method approach, for the first time, we could demonstrate the correlation between certain spectroscopically observed U species in solution and varying degrees of bioassociation to the plant as well as differences in U translocation patterns in <em>B. napus</em> between citric and malic acids, providing more insights into the interaction of U with plants.</div></div>","PeriodicalId":11758,"journal":{"name":"Environmental and Experimental Botany","volume":"238 ","pages":"Article 106248"},"PeriodicalIF":4.7,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145217023","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}