Tree physiology最新文献

{"title":"Species-specific budburst responses to diurnal temperature cycles during chilling and forcing in temperate deciduous trees.","authors":"Yann Vitasse, Günter Hoch, Steeve Pepin, Francesco Giardina","doi":"10.1093/treephys/tpag154","DOIUrl":"https://doi.org/10.1093/treephys/tpag154","url":null,"abstract":"<p><p>Cold temperatures ('chilling') perceived by tree buds progressively release winter dormancy and initiate sensitivity to warmer temperatures ('forcing') required for budburst. Phenology of temperate trees may also respond to daylength, but it remains unclear whether chilling and forcing accumulation is linked to the diurnal cycle. Here, we tested whether chilling accumulation is influenced by light-dark cycle frequency, and whether forcing is more effective during daylight. We harvested twig cuttings from four temperate tree species (Fagus sylvatica, Carpinus betulus, Quercus robur and Acer pseudoplatanus) with contrasting chilling and forcing requirements. In Experiment 1, twigs were harvested in November and exposed to 3°C under three light-dark cycle frequencies: 12h light/12h dark, 6h/6h, and 4h/4h (1, 2 or 3 cycles/day) for one or two months (short vs. long chilling). Twigs were then transferred to two forcing regimes with the same daily mean but different day/night temperatures (25°C/10°C and 20°C/15°C). In Experiment 2, twigs were harvested after substantial chilling and exposed to opposite day/night forcing regimes (25°C/10°C vs. 10°C/25°C). In Experiment 1, shorter light-dark cycles under long chilling delayed budburst in C. betulus, whereas effects on budburst success depended on chilling duration in C. betulus and Q. robur. Interestingly, budburst occurred significantly earlier at 25°C/10°C than at 20°C/15°C in all species, up to 12 days in F. sylvatica, suggesting more effective daytime forcing or non-linear forcing accumulation. Experiment 2 demonstrated that forcing was more effective during daylight, with 10%, 19% and 51% more degree days required for budburst under warm nights in Q. robur, C. betulus and F. sylvatica, respectively, but no difference in A. pseudoplatanus. Our study shows that light-temperature interactions and non-linear forcing responses can shape budburst timing, implying that tree phenological responses to warming may depend not only on its magnitude but also on its timing within the diurnal cycle.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149216673","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":"Nitrogen physiology and metabolism of two contrasting Catalpa bungei genotypes in response to limited nitrogen availability.","authors":"Mengyan Zhou, Jing Zhou, Jiangting Wu, Chenlin Jia, Yang Wang, Jia Wei, Chunhui Yang, Guoxuan Xu, Shuaixu Yan, Longsheng Hu, Shurong Deng, Wenjun Ma, Junhui Wang, Zhi-Bin Luo","doi":"10.1093/treephys/tpag152","DOIUrl":"https://doi.org/10.1093/treephys/tpag152","url":null,"abstract":"<p><p>To investigate N physiology and metabolism of different Catalpa bungei (C. bungei) genotypes in response to low N availability, saplings of a genotype (Cbu22-03) with high N uptake efficiency and a genotype (CbuGu) with low N uptake efficiency were exposed to 10, 100, or 1000 μM NH4NO3. The greater root biomass and fine-root surface area in Cbu22-03, combined with its higher net influxes of NO3- and NH4+ and upregulated transcript levels of CbuNRT1.1 and CbuAMT1.2, corresponded to the increased NO3- and NH4+ concentrations and total N amounts in roots compared with CbuGu. Accordingly, δ15N in both roots and leaves of Cbu22-03 was lower than that of CbuGu. Low N supply led to decreased net influxes of NO3- and NH4+, and reduced NO3-/NH4+ concentrations of roots and leaves, NR activities, and total N amounts, while inducing the up-regulation of CbuNRT1.1, CbuAMT1.2, and CbuAHA2 transcript levels, which likely enhanced nitrogen use efficiency (NUE) in both genotypes. These data suggest that Cbu22-03 shows greater capacities of N uptake and assimilation than CbuGu under the three N conditions, and both genotypes of C. bungei decreased the processes of N metabolism in response to low N availability.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149196852","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":"Integrated multi-omics analysis of root transcriptomic, metabolomic, and bacterial-community responses associated with rhizobial inoculation and cadmium exposure in Robinia pseudoacacia.","authors":"Lan Gao, Xingyue Sun, Xinlei Wang, Shufeng Wang, Hongxia Du, Ming Ma","doi":"10.1093/treephys/tpag153","DOIUrl":"https://doi.org/10.1093/treephys/tpag153","url":null,"abstract":"<p><p>Cadmium (Cd) contamination threatens soil ecosystems and food security. Robinia pseudoacacia is a potential candidate for phytoremediation, but the molecular responses and root-associated microbial responses accompanying rhizobial symbiosis under Cd exposure remain incompletely understood. We integrated root transcriptomic, internal-root metabolomic, and 16S rRNA gene sequencing data to characterize responses to Cd exposure and rhizobial inoculation in SX, the high shoot-Cd accumulator, and HB, the low shoot-Cd accumulator. SX and HB exhibited distinct transcriptional patterns and exploratory candidate-metabolite profiles. In SX, the transcriptional responses were associated with the greater shoot Cd translocation reported previously for this genotype. In HB, rhizobial inoculation under Cd exposure was associated with broader changes in candidate metal-transport and compartmentalization genes, consistent with its previously reported greater root Cd retention. Rhizobial inoculation was also associated with higher candidate abundances of leucine, trehalose, palmitic acid, thymine, and pantothenates in HB, whereas inoculated SX showed higher candidate abundances of leucine and isoleucine but lower internal L-malic acid. Cd exposure, rhizobial inoculation, and root compartment were associated with variation in bacterial community composition, including abundance patterns involving Pseudomonas, Devosia, and Rhizobium. Exploratory Spearman correlation analyses revealed compartment-specific patterns of covariation between candidate metabolites and bacterial genera; however, no metabolite-genus association remained statistically significant after Benjamini-Hochberg correction in the rhizoplane, endosphere, or rhizosphere. None of the compartment-specific Procrustes tests indicated significant overall concordance between bacterial community composition and root-metabolite profiles. Collectively, these findings identify candidate genes, metabolites, and bacterial taxa and provide testable hypotheses that could inform future genotype selection and microbiome-assisted phytoremediation strategies.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149196871","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":"Sex-specific divergence in leaf phosphorus economy in Fraxinus velutina Torr. under short-term simulated nitrogen deposition.","authors":"Zhi-Rong Xu, Xue-Ying Ren, Liu Yang, Xiao-Qian Meng, Cheng-Yang Xu, Xin-Na Zhang, Tao Chen, Wen-Xue Wang, Qiu-Ling Ning","doi":"10.1093/treephys/tpag143","DOIUrl":"https://doi.org/10.1093/treephys/tpag143","url":null,"abstract":"<p><p>Atmospheric nitrogen (N) deposition can substantially alter nutrient balance and internal nutrient recycling in trees, yet how dioecious species regulate phosphorus (P) economy in a sex-specific manner under N enrichment remains poorly understood. We investigated how short-term N enrichment differentially modifies leaf functional traits, leaf stoichiometry, and nitrogen and phosphorus resorption efficiencies (NRE and PRE) in female and male Fraxinus velutina Torr. using a field canopy-spray experiment with two N addition levels. Although N addition consistently promoted leaf structural traits, neither sex nor the N × S interaction significantly affected leaf morphological traits, suggesting that sexual dimorphism in this species manifests primarily in nutrient economy rather than leaf structure. Under N enrichment, P-related traits exhibited pronounced sex-specific responses, with significant N × S interactions: under high N, females increased leaf P concentration and exhibited lower N:P, whereas males increased leaf N concentration, resulting in higher N:P. N addition reduced NRE in both sexes, but PRE responses differed markedly: PRE declined progressively in males under elevated N, while females maintained a moderate reduction in PRE. SMA and multivariate analyses further showed that nutrient resorption in males was more strongly associated with current-season stoichiometric variation, whereas in females, nutrient resorption showed a stronger association with P status. Together, these findings identify P balance as the primary axis of sex-specific nutrient regulation under N enrichment, with females maintaining more stable internal P homeostasis than males. This distinction that underscores the need to account for plant sex in assessments of dioecious tree responses to increasing atmospheric N deposition.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149138154","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":"Integrated analysis uncovers the role of circadian rhythm genes in cold adaptation of Kandelia obovata using the multi-omics data.","authors":"Chaoqun Xu, Ji-Cheng Wang, Ling Sun, Dong-Na Ma, Qian-Su Ding, Ling-Yu Song, Jing Li, Li-Han Zhuang, Xue-Yi Zhu, Haoliang Lu, Luzhen Chen, Guangcheng Chen, Changyi Lu, Hai-Lei Zheng","doi":"10.1093/treephys/tpag149","DOIUrl":"https://doi.org/10.1093/treephys/tpag149","url":null,"abstract":"<p><p>Kandelia obovata and Kandelia candel, two sister mangrove species within the genus Kandelia (Rhizophoraceae), exhibit pronounced differences in cold tolerance. However, the genetic basis underlying this adaptive divergence remains unclear. In this study, we assembled a high-quality, chromosome-level genome of K. candel (~225 Mb) to facilitate comparative genomic analysis with K. obovata. Functional enrichment revealed that expanded gene families in K. candel and contracted families in K. obovata were both significantly associated with transcription factor (TF) activity, highlighting TFs as potential key drivers of adaptive evolution. Using whole-genome resequencing data from 53 accessions across representative geographic ranges, we investigated population structure and identified genomic loci associated with environmental adaptation in K. obovata. Notably, temperature-responsive TFs were found to be involved in the circadian rhythm pathway. Through integrated genomic and transcriptomic analysis, we prioritized 18 circadian rhythm-related TFs, including PIF3, CCA1, LHY, and MYB family members such as PAP1, as high-priority candidates linked to cold adaptation in K. obovata. Enrichment analysis of the target genes regulated by these TFs further underscored the importance of flavonoid and phenylpropanoid metabolism under cold stress. Our results suggest that circadian rhythm genes, through their regulation of specialized metabolism, represent promising candidate regulators that may contribute to cold adaptation of K. obovata. This study provides not only key insights into the evolutionary mechanisms of mangrove cold resilience but also a valuable genomic resource for guiding conservation and assisted migration strategies under climate change.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149138173","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":"Chromosome-level genome assembly of Tilia mandshurica reveals divergence of duplicated TPP genes associated with fructose-rich nectar formation.","authors":"Lin Lin, Jiayi Du, Qingshan Li, Cong Yu, Le Chen, Wenzheng Li, Fucai Xia, Huaizhi Mu","doi":"10.1093/treephys/tpag151","DOIUrl":"https://doi.org/10.1093/treephys/tpag151","url":null,"abstract":"<p><p>Tilia mandshurica is an important woody nectar plant, but the genomic and transcriptional basis of its nectar sugar accumulation remains poorly understood. Here, we generated a chromosome-level reference genome for T. mandshurica and integrated comparative genomics, gene duplication analysis, RNA-seq across seven floral developmental stages, qRT-PCR validation, carbohydrate measurements and metabolite profiling. Gene family analysis revealed lineage-specific expansion of families involved in carbohydrate metabolism, ion transport and specialized metabolism. Ks and synteny analyses identified an ancient Eocene whole-genome duplication likely shared with Craigia yunnanensis, whereas duplication-mode analysis indicated that subsequent small-scale duplications contributed to lineage-specific duplicate retention. Among the enriched carbohydrate-related categories, trehalose-phosphatase activity provided a link between genome evolution and floral sugar accumulation. Sixteen trehalose-phosphate phosphatase (TPP) genes separated into fructose-positive C1 and fructose-negative C2 classes, with strong divergence at both the gene level (Δ = 1.060) and module level (Δ = 1.294). C1 TPP genes tracked fructose accumulation, whereas C2 genes followed starch-related developmental programs. Coexpression analysis further revealed contrasting network architectures: C1 TPP genes formed a convergent network with enriched vacuolar/tonoplast-related targets, whereas C2 genes showed a dispersed architecture with no consensus targets. C1-co-expressed candidates included genes related to vacuolar ion homeostasis, cell-wall/glycan remodeling, and isoprenoid/carotenoid metabolism. Together, these results support a model in which duplicated TPP genes are associated with distinct carbohydrate-associated transcriptional programs for starch remobilization and fructose-rich nectar formation. This study provides a genomic resource for Tilia and identifies candidate TPP-centered networks for nectar sugar accumulation in woody honey plants.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149137768","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":"Distribution, Development, and Function of Resin Canals in Conifers: Insights from Cellular and Genomic Perspectives.","authors":"Yi Feng, Shu Diao, Xiaohui Lin, Caixia Wang, Xiaoping Wang, Yangdong Wang, Hengfu Yin","doi":"10.1093/treephys/tpag150","DOIUrl":"https://doi.org/10.1093/treephys/tpag150","url":null,"abstract":"<p><p>Resin canals are tunnel-like tissue structures primarily responsible for synthesizing and secreting resin. They consist of specialized secondary metabolite-synthesizing epithelial cells and supportive subsidiary cells, which are arranged to form distinctive intercellular spaces. In conifers, resin canals can develop during normal development or be induced by environmental stimuli, which often form an interconnected network and play a crucial role in defense against pathogens and insects. Despite their importance in resin secretion and defense, the mechanisms underlying their formation and function remain poorly understood. In this review, we summarize recent advances in the study of resin canals in conifers from the perspectives of cellular development, defense mechanisms, and molecular regulation. We analyze the distribution patterns, subcellular characteristics and formation and developmental processes of resin canals across different conifer species. Based on studies of traumatic resin canals, we propose a developmental model that depicts the initiation from cambial activity to cell differentiation and canal formation. Furthermore, we focus on resin canal-specific genes and analyze the functions and expression patterns of identified related genes. With the advancement of conifer genome sequencing and single-cell technologies, future research on resin canal regulatory mechanisms and functions is facing unprecedented opportunities. We propose a strategic framework aimed at enhancing conifer breeding, particularly for traits such as stress resilience, disease resistance and wood quality.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149138229","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":"Response of Dormancy-associated MADS-box (DAM) and Flowering Locus T (FT) genes to contrasting temperature conditions during dormancy in apricot (Prunus armeniaca L.).","authors":"Alvaro Delgado, David Ruiz, Tzu-Fan Hsiang, Jose A Egea, Hisayo Yamane","doi":"10.1093/treephys/tpag148","DOIUrl":"https://doi.org/10.1093/treephys/tpag148","url":null,"abstract":"<p><p>Chilling requirement (CR) fulfilment is critical for successful flowering in temperate fruit trees. In mild-winter regions, several anomalies can occur when the cultivar-specific CR is not fully met, including irregular budbreak, bud abortion, and ultimately reduced fruit set. In this study, we examined the molecular regulation of dormancy release in three apricot (Prunus armeniaca L.) cultivars grown under contrasting climates (warm vs. cold/mild winters). We focused on Dormancy-associated MADS-box (DAM) genes and Flowering Locus T (FT) gene using RT-qPCR to evaluate their potential as molecular markers for endodormancy release and indicators of cultivar adaptability. Under moderate differences in chill accumulation between sites, gene expression patterns generally exhibited genotype-specific responses to chilling. Expression of DAM4-6 correlated with prolonged cold exposure and was progressively downregulated towards dormancy release. Faster DAM downregulation in warmer sites corresponded to shallower dormancy and earlier release, consistent with the forcing-shoot experiment results. Among these genes, DAM4 required greater chill exposure for downregulation and emerged as a potential physiological indicator of the transition from endodormancy to ecodormancy, downregulating once approximately 75% of cultivar-specific CR had been fulfilled. However, DAM expression showed limited variation among areas during the later stages, even though substantial differences were observed in the number of viable buds and fruit set in the high-chill cultivar. By contrast, FT expression appeared more sensitive to insufficient chilling in this cultivar. These findings suggest that DAM genes are reliable markers of endodormancy progression, whereas FT may serve as an indicator of flowering quality under suboptimal chill accumulation. Integrating molecular, phenological and climatic data could enhance predictions of endodormancy release and flowering success and facilitate the development of climate-resilient apricot cultivars and adaptive orchard management strategies under global warming.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149138203","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":"Influence of root morphology and mycorrhizal type on root exudation rates among 10 co-existing broadleaved tree species in a cool-temperate forest.","authors":"Erika Kawakami, Masayoshi Harada, Ayumi Katayama","doi":"10.1093/treephys/tpag133","DOIUrl":"10.1093/treephys/tpag133","url":null,"abstract":"<p><p>Identification of the factors explaining variations in tree root exudates is crucial for understanding belowground carbon dynamics. The relative importance of plant functional types and root morphological and physiological traits in explaining differences of root exudation remains unclear. To elucidate the key factors influencing root exudation, we examined root exudation rates, morphological traits (specific root length, specific root area, tissue density and diameter) and respiration rates across 10 co-existing tree species in the absence of significant environmental gradients. The selected species differed in life form (deciduous and evergreen) and mycorrhizal type (arbuscular (AM) and ectomycorrhizal (ECM)). No significant differences (F = 0.001, P = 0.97) in root exudation rates were observed between life forms, whereas significant differences were observed between mycorrhizal types (F = 10.94, P < 0.01), with AM species exhibiting significantly higher exudation rates than those of ECM species. Principal component analysis among the species revealed that root exudation rate was associated with resource acquisition traits characterized by a smaller diameter along the first axis. Along the second axis, it was more closely linked with lower tissue density reflecting mycorrhizal types. Crucially, the best model for explaining the root exudation rate included diameter and mycorrhizal type, while root respiration rate, as a proxy of physiology, was not selected. These findings suggest that mycorrhizal type is a more dominant factor than life form among the 10 species. Furthermore, they reveal that variations in root exudation cannot be explained by morphological and physiological traits alone, highlighting the importance of accounting for both mycorrhizal identity and root morphology among the 10 studied co-existing broadleaved species. This study underscores the importance of considering mycorrhizal-specific processes to better understand belowground carbon cycling.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148956805","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":"Comparative physiological, transcriptomic and metabolomic analyses reveal the mechanisms underlying the exceptionally long internodes in bamboo (Bambusa distegia).","authors":"Xin Zhao, Li Zhang, Man Tang, Yan Huang, Zhijian Long, Chulin Zhou, Gang Xu, Shangmeng Li, Boya Wang, Mengyao Kong, Lin Li, Xin Wang, Ying Cao, Shanglian Hu","doi":"10.1093/treephys/tpag137","DOIUrl":"10.1093/treephys/tpag137","url":null,"abstract":"<p><p>Bamboo has emerged as a globally significant sustainable resource, playing an increasingly vital role in 'bamboo-for-plastic' initiatives and other green industries. Internode length represents a key agronomic trait that determines fiber yield and processing efficiency in bamboo. To elucidate the mechanisms governing internode elongation, this study investigated Bambusa distegia (Keng & Keng f.) L.C.Chia & H.L.Fung, a species characterized by exceptionally long internodes (over 100 cm). Comparative analysis of growth dynamics with Phyllostachys edulis (Carrière) J.Houz. and Dendrocalamus farinosus (Keng & Keng f.) L.C.Chia & H.L.Fung, and cytological comparison between B. distegia and P. edulis, revealed that B. distegia exhibited a growth duration of ~60 days for its longest internode, compared with ~20 days for P. edulis and ~40 days for D. farinosus, indicating that the extended internodes in B. distegia originate from prolonged growth duration and increased cell number, rather than accelerated elongation rate or enhanced cell length. Integrated histological, transcriptomic and metabolomic analyses demonstrated that sustained cytokinin signaling serves as the key mechanism maintaining prolonged cell division activity. Through weighted gene co-expression network analysis and co-expression network construction, core regulatory factors were identified, including cytokinin biosynthetic enzymes (CYP735A), modifying enzymes (UGT85A), cell cycle regulators (CYCD3/CYCA3) and key transcription factors (ERF, TCP14). This study systematically clarifies the molecular basis of long internode formation in bamboo and provides valuable genetic targets and theoretical support for breeding industrial bamboo varieties with optimized internode structure and enhanced utilization efficiency, thereby promoting sustainable utilization and value-added development of bamboo resources.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":4.0,"publicationDate":"2026-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149012817","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}