Tree physiology最新文献

{"title":"Excision increases branch water potential but generally reduces leaf gas exchange.","authors":"Marcella Cross, Sean T Michaletz","doi":"10.1093/treephys/tpag035","DOIUrl":"10.1093/treephys/tpag035","url":null,"abstract":"<p><p>Measurement of leaf gas exchange is often complicated by the difficulty of sampling leaves from tall or otherwise inaccessible plants. Branch excision is widely used to enable such measurements, but the magnitude, variability, and mechanisms of its effects on water potential and gas exchange are not well characterized across species and environments. We quantified the effects of excision on branch water potential, stomatal conductance, photosynthesis, and stomatal behaviour (parameter g1) in four angiosperm and one gymnosperm tree species differing in hydraulic traits and water-use strategies. To assess generality, we also conducted a meta-analysis of 26 species spanning a broad range of hydraulic traits, water-use strategies, and biomes. Excision consistently increased branch water potential in all species. In angiosperms, excision reduced stomatal conductance and photosynthesis, with decreases in g1 for some species, whereas in the gymnosperm, excision increased stomatal conductance, photosynthesis, and g1. The meta-analysis showed that excision generally decreased stomatal conductance and photosynthesis, with effect sizes varying by species, water-use strategy, and hydraulic traits. These results demonstrate that the effects of excision are strongly species- and trait-dependent. Careful consideration and study-specific corrections are needed when interpreting gas exchange data from excised branches.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147723808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glutathione promotes somatic embryogenesis by regulating ThGPX4 in Taxodium hybrid 'zhongshanshan'.","authors":"Tingting Chen, Xinrui Tang, Dan Wang, Guoying Yuan, Yunlong Yin, Chaoguang Yu","doi":"10.1093/treephys/tpag046","DOIUrl":"https://doi.org/10.1093/treephys/tpag046","url":null,"abstract":"<p><p>Somatic embryogenesis (SE) in conifers is significantly genotype-dependent. In this study, multiple genotypes of Taxodium hybrid 'zhongshanshan' callus were treated with GSH (glutathione), BSO (Buthionine-sulfoximine, GSH synthesis inhibitor) and OTC (L-2-oxothiazolidine-4-carboxylate, increase the intracellular accumulation of GSH) to clarify that GSH significantly promoted SE efficiency and improved callus status. Determination of physiological indices revealed that GSH facilitated SE by enhancing antioxidant capacity, with the most significant differences observed at the dominant embryo stage. Transcriptome analysis indicated that the differentially co-expressed genes (DEGs) in the GSH-treated and BSO-treated groups were mainly enriched in the Glutathione metabolism, Protein processing in endoplasmic reticulum, Ascorbate and aldarate metabolism, and Pentose and glucuronate interconversions, and most of these DEGs were associated with antioxidant activity. Furthermore, we found that the glutathione peroxidase gene (ThGPX4) was significantly up-regulated after GSH treatment. Functional analysis showed that ThGPX4 had the highest expression at the dominant embryo stage and was located in both the nucleus and cytoplasm. Overexpression of ThGPX4 significantly enhanced SE in Arabidopsis thaliana. Using transient genetic transformation technology to overexpress ThGPX4 in Taxodium hybrid 'zhongshanshan' embryogenic calli, we observed that ThGPX4 could regulate the GSH/GSSG (reduced glutathione/oxidized glutathione) ratio, reduce H₂O₂ (hydrogen peroxide) content, and inhibit the activities of SOD (superoxide dismutase) and POD (peroxidase). These results indicated that GSH treatment can activate the expression of genes like ThGPX4 and consequently increases the antioxidant capacity of calli and enhances SE efficiency. The present study provides a valuable basis on the solution of the genotype recalcitrance in conifer SE.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147692445","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Emission variations of GLVs from woody plants upon mechanical damage reflect trait-mediated physio-ecological adaptation strategies.","authors":"Yali Yuan, Yimiao Mao, Guomo Zhou, Ülo Niinemets, Zhihong Sun","doi":"10.1093/treephys/tpag045","DOIUrl":"https://doi.org/10.1093/treephys/tpag045","url":null,"abstract":"<p><p>Mechanical damage markedly modifies the emission patterns of green leaf volatiles (GLVs), which serve as key signaling compounds in plant defense, yet interspecific variations across diverse tree species and their linkage to ecological adaptation remain poorly characterized. This study systematically analyzed GLVs (aldehydes, alcohols, esters) in 45 tree species (19 deciduous, 26 evergreen) under both intact and mechanically wounding conditions, integrating leaf functional traits and ecological strategy types. Intact leaves emitted low levels of GLVs, primarily esters. Wounding increased total emissions 5- to 200-fold, with alcohols and aldehydes rising most sharply; over 80% of post-wounding compounds were newly induced. Deciduous species exhibited significantly higher GLVs emissions and wound responsiveness than evergreens. GLVs emissions correlated closely with leaf dry mass per area (LMA, negative) and leaf water content (LWC, positive), and differed among ecological strategy types. Wounding enhanced synergies between GLVs, monoterpenes, and aromatic compounds within the BVOC blend, forming an integrated defense network whose structure depended on life form. GLV emission patterns also aligned with species' dominant volatile metabolism: isoprene emitting deciduous trees showed intense aldehyde bursts, whereas monoterpene emitting evergreens maintained stronger ester monoterpene coupling. Our findings demonstrate that mechanical injury reprograms GLV emissions in a trait- and strategy-dependent manner, reflecting evolutionary trade-offs between growth and defense. This study provides a trait-based physio-ecological framework that links leaf economics, volatile metabolism, and network-level coordination, offering a mechanistic basis for selecting stress-resilient trees and refining forest emission models under environmental disturbance.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147692451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plant functional trait differentiation and microbial life-history strategy shifts drive soil respiration under long-term forest restoration.","authors":"Haocai Wang, Dongrui Di, Sheng Du, Ryunosuke Tateno, Josep Peñuelas, Mirco Migliavacca, Qiuwen Chen, Jinhong Guan, Yi Song, Weiyu Shi","doi":"10.1093/treephys/tpag042","DOIUrl":"https://doi.org/10.1093/treephys/tpag042","url":null,"abstract":"<p><p>Soil respiration (Rs) represents a major carbon (C) flux linking plant productivity with microbial decomposition; however, the mechanisms by which contrasting forest restoration pathways regulate Rs and its components remain insufficiently understood. We conducted a six-year field observation (2017-2022) across abandoned farmland (AF), Quercus liaotungensis forest (QF), and Robinia pseudoacacia plantation (RP) on the Loess Plateau, China, integrating measurements of Rs, autotrophic (Ra), heterotrophic (Rh), plant functional traits, soil physicochemical properties, and microbial C metabolic potential. Afforestation significantly increased Rs, with a stronger enhancement observed in QF than in RP. Although Ra did not differ significantly between the two forest types, Rh accounted for approximately 70% of Rs and primarily explained the significant differences in Rs between restoration pathways. Elevated Rh in QF was strongly associated with greater abundances of microbial functional genes involved in the degradation of C substrates. Integrated analyses further revealed that differentiation in plant functional traits between QF (conservative strategy) and RP (acquisitive strategy) indirectly amplified Rh contributions to Rs by reshaping soil substrate availability and coordinating shifts in microbial life-history strategies. Collectively, our findings identify plant functional trait differentiation as a key driver of long-term Rs dynamics, mediated by shifts in microbial life-history strategies.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147677033","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sulfur nanoparticles enhance Cd-phytoremediation in Salix chaenomeloides via alleviating phytotoxicity and modulating rhizosphere microbiota.","authors":"Yaping Wang, Yichen Xu, Yini Cao, Chuanxin Ma, Zeyu Cai, Jason C White, Yunpeng Wang, Guangcai Chen, Wende Yan, Baoshan Xing","doi":"10.1093/treephys/tpag041","DOIUrl":"https://doi.org/10.1093/treephys/tpag041","url":null,"abstract":"<p><p>Sulfur application can enhance plant tolerance to toxic metal stress, but the the underlying physiological and microecological mechanisms in woody plants remain poorly understood. In this study, Salix chaenomeloides was treated with sulfur nanoparticles (S NPs) at dosages of 60 and 120 mg∙kg-1 under cadmium (Cd) stress. We evaluated the in planta physiological responses and rhizosphere microbial processes mediating Cd tolerance and phytoremediation efficiency. Sulfur application (sulfate and S NPs) significantly stimulated Salix growth, increasing above-ground and root biomass by 15.2-28.6% and 26.9-49.5%, respectively, compared to Cd alone treatment. Notably, S NPs outperformed sulfate in alleviating Cd-induced oxidative damage, reducing malondialdehyde and superoxide anion contents by 22.4-23.8% and 82.9-84.5%, respectively, compared to Cd alone. Under Cd stress, 120 mg∙kg-1 S NPs application significantly increased glutathione and oxidized-glutathione contents by 8.96% and 33.0%, respectively, compared to Cd alone. S NPs significantly upregulated the expression of genes involved in metal transport and sulfur metabolism. The abundance of the Cd tolerance gene czcC and sulfur transformation genes (cysH, dsrA and soxB) was significantly increased by S NPs application under Cd stress. The expression levels of functional genes linked to the S-cycle showed a noteworthy positive relationship with the translocation factor of Cd in shoots and the total accumulation of Cd. These findings demonstrate that S NPs represent a safe and sustainable strategy to enhance Cd phytoextraction and mitigate phytotoxicity in Salix.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147639882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The formation of ethylene-induced heartwood zone in Dalbergia odorifera: mechanism and insights into natural heartwood development.","authors":"Houzhen Hu, Xiaojin Liu, Zhiyi Cui, Xiaofei Li, Daping Xu, Tengkuan Su, Boyong Liao, Qilei Zhang, Zhou Hong, Yu Su","doi":"10.1093/treephys/tpag025","DOIUrl":"10.1093/treephys/tpag025","url":null,"abstract":"<p><p>Dalbergia odorifera T. Chen, an economically and medicinally valuable tree, suffers from heartwood shortage due to slow natural formation. Ethylene has emerged as a potent inducer of heartwood formation in D. odorifera, but long-term evidence and mechanisms remain unclear. To bridge this gap, we systematically assessed dynamic changes in morphology, anatomy, metabolomics and antimicrobial properties of ethylene-induced heartwood zone over 1, 3 and 5 years, comparing it with 20-year-old natural heartwood. Results showed that in the ethylene-stimulated zone, heartwood resins were initially deposited at the outermost layer and progressively infiltrated inward until full saturation. The coloration of induced heartwood zone gradually intensified, eventually developing hues and grain patterns resembling natural heartwood by 5 years. Heartwood extracts yield and antimicrobial activity matched natural heartwood after 1 year. Total flavonoid content matched natural heartwood by 3 years, with nine flavonoid components (e.g. naringenin, formononetin) governing color development. While volatile compounds composition matched natural heartwood after 5 years, flavonoid profiles remained distinct, indicating volatile compounds biosynthesis preceded flavonoids. More interestingly, this study proposed a novel hypothesis for heartwood formation: during natural heartwood development, a certain factor (e.g. ethylene) induces a transition zone containing numerous 'micro-zones,' where cell death and heartwood substance deposition progress gradually from the outer to inner layers. This pattern leaves residual sapwood within developing heartwood, effectively resolving the theoretical conflict regarding the presence of living cells in heartwood. Thus, this study not only confirms the long-term feasibility of ethylene-induced heartwood zone formation and its underlying mechanisms, but also proposes a groundbreaking hypothesis that challenges conventional understanding of heartwood formation, laying a crucial foundation for future research on heartwood formation mechanisms and targeted cultivation of high-value tree species.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146259232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leaf pigment composition: a window into how plants cope with environmental stress.","authors":"Kouki Hikosaka","doi":"10.1093/treephys/tpag037","DOIUrl":"10.1093/treephys/tpag037","url":null,"abstract":"","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147504956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Yearly changes in the use of stored carbon to develop new aboveground organs of young and mature apple trees.","authors":"Shogo Imada, Takashi Tani, Yuki Moriya","doi":"10.1093/treephys/tpag028","DOIUrl":"10.1093/treephys/tpag028","url":null,"abstract":"<p><p>Temperate deciduous trees depend on stored carbon for their growth and metabolic processes in early spring. Despite their importance, annual changes in the contribution of stored carbon to the development of new organs are not adequately understood. We conducted 13C labelling experiments on apple (Malus domestica) saplings and a mature tree grown under normal conditions, and investigated 13C concentration in new aboveground organs in early spring for several years after labelling. In the saplings, assimilated 13C during the growing season was detected in the terminal buds around the bud break from the first to the fourth year after labelling. Similar results were found in the flower buds, leaves and annual shoots of mature trees pink bud stage, in which the concentration of assimilated 13C was detected from the first to the third year after labelling. The concentration of assimilated 13C in the new organs of saplings and mature trees decreased exponentially over time after labelling. The reduction patterns of the assimilated 13C in the new organs of the saplings and mature trees fit better with the two-pool than the one-pool exponential models, indicating that while stored carbon in fast and slow pools was included in the new organs, almost all stored carbon used was from the fast pool. Our findings also suggested that the use of stored carbon in the development of new organs in early spring would not differ between saplings and mature trees.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146228818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The transcription factor PsLBD42 promotes low nitrogen-induced anthocyanin biosynthesis in poplar.","authors":"Zimao Feng, Zhaoyou Yu, Mingjun Li, Chunxia Zhang","doi":"10.1093/treephys/tpag034","DOIUrl":"10.1093/treephys/tpag034","url":null,"abstract":"<p><p>Plants have developed intricate mechanisms to adapt to fluctuating nitrogen availability in the soil, including modulation of anthocyanin biosynthesis. However, the regulation mechanism of lateral organ boundary domain (LBD) transcription factors on anthocyanin biosynthesis under low nitrogen (LN) conditions remains poorly understood. Here, we functionally characterized PsLBD42 from Populus simonii, a class II LBD transcription factor, which was upregulated under LN conditions. PsLBD42-overexpression transgenic poplar exhibited enhanced resistance to the LN stress with increased photosynthetic rates and decreased photooxidation, but unchanged nitrogen content and uptake capability. Meanwhile, the accumulation of anthocyanin was significantly increased in the leaves of PsLBD42-overexpression transgenic poplar. The contrary results were shown in the lines of PsLBD42-suppression transgenic poplar. It was confirmed that PsLBD42 could directly bind to the promoters of PsUGT78D2 and PsUGT79B3 in the genes of anthocyanin pathway by yeast one-hybrid, dual luciferase and ChIP-qPCR assays. Under LN conditions, overexpression of PsUGT78D2 and PsUGT79B3 in the poplar leaves accumulated more anthocyanins while the suppression of PsUGT78D2 and PsUGT79B3 reduced anthocyanins content. Furthermore, overexpression of PsUGT78D2 and PsUGT79B3 restored anthocyanin levels in PsLBD42-RNAi lines under LN conditions. Collectively, our results indicate that the PsLBD42-PsUGT78D2/PsUGT79B3 module regulates anthocyanin accumulation in poplar leaves as a novel mechanism to enhance poplar tolerance to LN stress.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147445196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drought and methyl jasmonate deplete non-structural carbohydrates to similar levels but induce divergent terpene responses in Pinus edulis seedlings.","authors":"Franklin Alongi, Shealyn C Malone, Danielle E M Ulrich, Sean L Hoy-Skubik, Amy M Trowbridge","doi":"10.1093/treephys/tpag030","DOIUrl":"10.1093/treephys/tpag030","url":null,"abstract":"<p><p>Drought and herbivory are prevalent stressors that often interact to constrain forest regeneration. Drought-induced depletion of nonstructural carbohydrates (NSC) may impair seedling chemical defenses, increasing vulnerability to pests and pathogens. To investigate NSC thresholds influencing defense capacity, we quantified the effects of drought and simulated insect herbivory on NSC (starch, sucrose, glucose and fructose) and mono- and sesquiterpene (MST) defenses in 5-year-old piñon pine (Pinus edulis) seedlings. Seedlings were either well-watered or subjected to drought until stomatal closure before treatment with methyl jasmonate (MeJA) to simulate herbivory. Both drought and MeJA treatments individually reduced NSC content in needles and stems by 50%, with no further decrease observed under combined stressors. Regardless of stressor(s), NSC was depleted to ~0.5% and ~0.7% dry weight in needles and stems, respectively. While drought alone more than doubled MST concentrations in both tissues, total MST concentrations remained unchanged in response to MeJA, suggesting NSC was instead mobilized to support other unidentified metabolic processes. By demonstrating that NSC were depleted to similar lower limits across all stressors and combinations, this study suggests the existence of reserve thresholds below which seedling capacity to respond to subsequent stress may become constrained.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.7,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147445223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}