New Phytologist最新文献

{"title":"Mutations in SUMO conjugating enzyme reveal contributions of sumoylation to plant stress resilience and yield","authors":"Lilian Nehlin, Sadia Sabrina Alam, Junaid Shehzad, Bushra Ijaz, Jose Julián, Nikola Winter, Andreas Bachmair","doi":"10.1111/nph.71581","DOIUrl":"https://doi.org/10.1111/nph.71581","url":null,"abstract":"Summary <jats:list list-type=\"bullet\"> <jats:list-item> Small ubiquitin‐related modifier (SUMO) conjugation is a fundamental process in all metazoa, with multiple roles in development and stress responses. In <jats:italic>Arabidopsis thaliana</jats:italic> and many other dicots, the SUMO conjugating enzyme (SCE) is a single‐copy gene, making it a linchpin in all transcriptional and posttranscriptional processes influenced by sumoylation. Loss of function of Arabidopsis SCE1 is lethal, but we were able to generate a hypomorphic (decrease‐of‐function; <jats:italic>sce1‐100</jats:italic> ) and a hypermorphic (increase‐of‐function; SCE1 K28R) allele of this gene. </jats:list-item> <jats:list-item> The hypomorphic allele has traits in common with a mutant defective in SUMO ligase SIZ1, compromising development and stress resilience. We compare transcriptional responses of <jats:italic>sce1‐100</jats:italic> and <jats:italic>siz1</jats:italic> and define processes that depend on SUMO but are independent of salicylic acid, a plant hormone that accumulates upon a decrease in sumoylation. </jats:list-item> <jats:list-item> The hypermorphic allele SCE1 K28R impacts on plants under normal glasshouse conditions, leading to higher seed yield. Under the stress of low nitrogen supply, these plants show increased root foraging, facilitating nitrogen uptake under limiting conditions. </jats:list-item> <jats:list-item> The two SCE1 mutant alleles provide a valuable framework for uncovering processes with SUMO participation. Due to their NGT1 (non‐transgenic) legal status, experiments outside transgene confinement facilities will be possible with these mutants. </jats:list-item> </jats:list>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"5 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2026-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149043585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupled decline in growth and fine‐branching signals the onset of drought‐induced European beech mortality","authors":"Gerhard Schmied, Dominik Ambs, Luke Bohnhorst, Julia Schmucker, Jill Sekely, Hans Pretzsch, Lars Opgenoorth, Katrin Heer, Stephan Raspe, Torben Hilmers, Richard L. Peters","doi":"10.1111/nph.71606","DOIUrl":"https://doi.org/10.1111/nph.71606","url":null,"abstract":"Summary <jats:list list-type=\"bullet\"> <jats:list-item> Severe and recurrent droughts have caused widespread canopy decline and mortality in European forests. Drought‐induced mortality occurs when structural damage and physiological dysfunction impair a tree's ability to recover, yet it remains unclear when trees transition from reversible stress to irreversible vitality loss at the whole‐tree level. </jats:list-item> <jats:list-item> We combined detailed information on fine‐branching architecture derived from terrestrial laser scanning with radial growth data from 174 trees to assess how structural and growth decline relate to drought‐induced mortality in European beech ( <jats:italic>Fagus sylvatica</jats:italic> ). </jats:list-item> <jats:list-item> We found that European beech trees cross a critical tipping point under drought stress when pronounced declines in fine‐branching and radial growth occur together. Mortality probability increased sharply once relative twig length (= fine‐branching) dropped below <jats:italic>c.</jats:italic> 325 m m <jats:sup>−3</jats:sup> and relative growth fell below <jats:italic>c.</jats:italic> 7%, equaling a ≥ 75% mortality probability within 3 yr, whereas neither indicator alone reliably captured this transition. </jats:list-item> <jats:list-item> Our results demonstrate that drought‐induced vitality loss in an angiosperm follows distinct trajectories but converges on a critical zone of coupled crown and growth decline that marks an ‘area of no return.’ Linking crown deterioration with growth performance provides a mechanistic early‐warning signal of irreversible vitality loss under intensifying climate extremes. </jats:list-item> </jats:list>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"11 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2026-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149027561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phytochemical divergence between above‐ and belowground tree organs along elevational gradients","authors":"Mengesha Asefa, Lu Sun, Yazhou Zhang, Susan R. Whitehead, Guorui Xu, Xiaoyang Song, Min Cao, Yunyun He, Yao Su, Jie Yang, Nathan G. Swenson","doi":"10.1111/nph.71603","DOIUrl":"https://doi.org/10.1111/nph.71603","url":null,"abstract":"Summary <jats:list list-type=\"bullet\"> <jats:list-item> Plants produce diverse metabolites to defend against biotic and abiotic stresses. However, quantification of plant chemical defenses along environmental gradients has largely focused on aboveground organs, leaving belowground patterns poorly understood. </jats:list-item> <jats:list-item> To address how leaf and root defense chemistry shifts with changing biotic and abiotic conditions, we compared untargeted metabolomics of 183 species across elevational gradients spanning tropical, subtropical, and subalpine forests. </jats:list-item> <jats:list-item> Leaves and roots showed distinct chemical compositions across elevations, with phytochemical diversity declining from tropical to subalpine forests, corresponding with shifts in herbivore pressure and soil conditions. These patterns suggest that local variation in biotic and abiotic pressures across elevations may be associated with gradients in phytochemical diversity. We also uncovered contrasting patterns of chemical strategies between organs. Leaf chemistry shifts from polar, fast‐turnover, low‐cost metabolites in tropical forests to less polar, aromatic, and energetically costly metabolites in subtropical and subalpine forests, whereas roots display contrasting metabolic adjustments. </jats:list-item> <jats:list-item> Our results suggest that elevation filters species by their distinct metabolomic profiles, with organ‐specific and context‐dependent chemical investment, highlighting the importance of integrating above‐ and belowground organs to understand plant chemical responses across gradients. We reveal that organs of the same tree tell distinct chemical stories, illuminating the chemical life of trees. </jats:list-item> </jats:list>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"47 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149019813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A hypermorphic allele of CNGC confers broad‐spectrum blast resistance through ectopic calcium influx‐induced cell death in rice","authors":"Jianbin Liu, Gui Xiao, Hai Liu, Yi Liang, Zhaofeng Yi, Bin Bai, Xiushuo Liang, Sheng Luo, Fang Yuan, Jie Yang, Shaowu Xue, Wenxian Sun, Bo Zhou, Jun Wu","doi":"10.1111/nph.71579","DOIUrl":"https://doi.org/10.1111/nph.71579","url":null,"abstract":"Summary <jats:list list-type=\"bullet\"> <jats:list-item> Rice blast, caused by <jats:italic>Magnaporthe oryzae</jats:italic> , is one of the most destructive diseases threatening global rice production. Race‐independent broad‐spectrum resistance (BSR) holds the ideal strategy for durable rice blast management, yet its molecular mechanisms remain largely obscure. </jats:list-item> <jats:list-item> Here, we identified and characterized <jats:italic>elicitor‐triggered cell death 1</jats:italic> ( <jats:italic>etd1</jats:italic> ), a rice lesion mimic mutant that displays spontaneous cell death and hypersensitive response (HR)‐like necrosis upon challenge with <jats:italic>M. oryzae</jats:italic> elicitors. </jats:list-item> <jats:list-item> Genetic analysis reveals that <jats:italic>etd1</jats:italic> encodes a hypermorphic haplotype of rice Cyclic Nucleotide‐Gated Channel 13 (OsCNGC13) protein, harboring a single glycine‐to‐glutamic acid substitution (G483E) in the highly conserved gating domain of the CNGC family. This mutation transforms OsCNGC13 into a hyperactive Ca <jats:sup>2+</jats:sup> ‐permeable channel (etd1), driving ectopic Ca <jats:sup>2+</jats:sup> influx under both developmental and pathogenic conditions that lead to cell death. Although detrimental to agronomic traits, <jats:italic>etd1</jats:italic> confers robust BSR against all 108 tested <jats:italic>M. oryzae</jats:italic> isolates by effectively blocking fungal colonization through ectopic Ca <jats:sup>2+</jats:sup> influx‐induced cell death. </jats:list-item> <jats:list-item> Our data demonstrate that hyperactivation of a Ca <jats:sup>2+</jats:sup> ‐permeable channel can confer rice BSR through Ca <jats:sup>2+</jats:sup> ‐mediated cell death. The discovery of <jats:italic>etd1</jats:italic> provides a valuable clue for breeding rice with broad‐spectrum blast resistance based on Ca <jats:sup>2+</jats:sup> ‐permeable channels. </jats:list-item> </jats:list>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"1 1","pages":""},"PeriodicalIF":9.4,"publicationDate":"2026-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149019968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The miR167–ARF8 module coordinates stamen–pistil development and fruit set in tomato","authors":"Nave Man,&nbsp;Naama Teboul,&nbsp;Amir Bahu,&nbsp;Moritz Friesch,&nbsp;Alon Israeli,&nbsp;Tzahi Arazi,&nbsp;Bettina Hause,&nbsp;Naomi Ori","doi":"10.1111/nph.71503","DOIUrl":"10.1111/nph.71503","url":null,"abstract":"<p>\u0000 \u0000 </p>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"252 2","pages":"647-665"},"PeriodicalIF":8.7,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.71503","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148703430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The PtoERF1-PtomiR393a-PtoFBL4 module confers drought tolerance via ABA–auxin crosstalk in Populus","authors":"Yongming Chen,&nbsp;Mingyang Quan,&nbsp;Dan Wang,&nbsp;Shitong Qin,&nbsp;Wencong Zhang,&nbsp;Yingrui Zhao,&nbsp;Yuyan Wang,&nbsp;Yongsen Jiang,&nbsp;Yuling He,&nbsp;Rui Huang,&nbsp;Mingyue Gu,&nbsp;Yicen Guan,&nbsp;Qingzhang Du,&nbsp;Pär K. Ingvarsson,&nbsp;Yousry A. El-Kassaby,&nbsp;Deqiang Zhang","doi":"10.1111/nph.71520","DOIUrl":"10.1111/nph.71520","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 \u0000 </p><ul>\u0000 \u0000 \u0000 <li>Drought stress limits forest tree growth and adaptation, with xylem vessels critical for hydraulic transport and structural integrity. However, the molecular mechanisms of abscisic acid (ABA)–auxin interaction in regulating vessel morphogenesis under water-deficit conditions remain unclear.</li>\u0000 \u0000 \u0000 <li>Here, we identified PtomiR393a, a drought-responsive microRNA in <i>Populus tomentosa</i> that mediates crosstalk between ABA and auxin signaling pathways under drought stress.</li>\u0000 \u0000 \u0000 <li>Suppressing PtomiR393 enhanced drought tolerance and growth, whereas its overexpression had the opposite effect. Under drought conditions, suppression of PtomiR393 resulted in reduced vessel size (12.18–13.57%) and increased vessel density (27.22–30.14%), while its overexpression exhibited increased vessel size (15.42–16.01%) and reduced vessel density (19.80–20.62%). Functional assays showed that PtomiR393 specifically targets <i>PtoFBL4</i>, an F-box auxin receptor, modulating auxin signaling in response to drought stress. Expression analyses further revealed that PtomiR393 downregulates genes involved in vessel and fiber formation and secondary cell wall biosynthesis by repressing <i>PtoFBL4</i>-mediated auxin signaling. Furthermore, drought-induced ABA signaling activated <i>PtoERF1</i> expression via PtoAREB13, thereby inhibiting PtomiR393a expression.</li>\u0000 \u0000 \u0000 <li>The study revealed a PtoERF1-PtomiR393a-PtoFBL4 cascade that links ABA–auxin crosstalk and regulates vessel development under drought stress. These findings offer new insights into drought tolerance mechanisms in trees and suggest potential strategies to enhance forest tree resilience to water-deficit conditions.</li>\u0000 </ul>\u0000 \u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"252 2","pages":"705-723"},"PeriodicalIF":8.7,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148833749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Methodological considerations in the analysis of guard cell starch metabolism","authors":"Katharina Fink,&nbsp;Trang Dang,&nbsp;Carlo Pasini,&nbsp;Hongyuan Zhang,&nbsp;Lucia Piro,&nbsp;Diana Santelia","doi":"10.1111/nph.71446","DOIUrl":"10.1111/nph.71446","url":null,"abstract":"&lt;p&gt;Stomata are microscopic pores on the leaf surface that regulate CO&lt;sub&gt;2&lt;/sub&gt; uptake for photosynthesis and water loss through transpiration. Their aperture is controlled by the turgor pressure of the two surrounding guard cells (GCs), which respond dynamically to environmental cues (Zhang &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2024&lt;/span&gt;). Among these, blue light (BL) is a key signal that promotes stomatal opening, primarily by activating plasma membrane H&lt;sup&gt;+&lt;/sup&gt;-ATPases for potassium (K&lt;sup&gt;+&lt;/sup&gt;) uptake, water influx, and subsequent GC swelling (Inoue &amp; Kinoshita, &lt;span&gt;2017&lt;/span&gt;). In &lt;i&gt;Arabidopsis thaliana&lt;/i&gt;, BL signaling not only activates ion transport but also triggers rapid degradation of starch in GC chloroplasts, releasing glucose, part of which is subsequently converted to malate (Horrer &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2016&lt;/span&gt;; Flutsch &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2020&lt;/span&gt;). These metabolites are essential for stomatal opening, as they provide counterions for K&lt;sup&gt;+&lt;/sup&gt; and carbon skeletons for energy production, while also contributing to osmotic adjustment (Santelia &amp; Lawson, &lt;span&gt;2016&lt;/span&gt;; Daloso &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2017&lt;/span&gt;). Arabidopsis mutants unable to degrade starch in GCs show a strongly impaired stomatal opening response to BL due to metabolic insufficiency (Horrer &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2016&lt;/span&gt;). Through this coordinated activation of proton pumping, ion transport, and starch degradation, BL efficiently couples energy availability with gas exchange and photosynthetic activity (Lawson &amp; Matthews, &lt;span&gt;2020&lt;/span&gt;).&lt;/p&gt;&lt;p&gt;This model was challenged by a recent &lt;i&gt;New Phytologist&lt;/i&gt; article by Bahadar &lt;i&gt;et al&lt;/i&gt;. (&lt;span&gt;2025&lt;/span&gt;). Using metabolic and stomatal analyses in Arabidopsis, cowpea (&lt;i&gt;Vigna unguiculata&lt;/i&gt;), and tobacco (&lt;i&gt;Nicotiana tabacum&lt;/i&gt; L.), the authors reported that starch in GCs was not degraded during BL-induced stomatal opening in any of the species examined.&lt;/p&gt;&lt;p&gt;In Arabidopsis, GC starch degradation in response to stimuli that induce stomatal opening (e.g. BL, dark-to-light transition, exposure to low CO&lt;sub&gt;2&lt;/sub&gt;) has been consistently observed in different laboratories (Horrer &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2016&lt;/span&gt;; Flutsch &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2020&lt;/span&gt;; Li &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2020&lt;/span&gt;; Han &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2022&lt;/span&gt;; Shi &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2024&lt;/span&gt;; Gurrieri &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2025&lt;/span&gt;; Silva-Alvim &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2026&lt;/span&gt;). Furthermore, starch degradation in response to light has also been observed in other species, such as lettuce (&lt;i&gt;Lactuca sativa&lt;/i&gt;), apple (&lt;i&gt;Malus domestica&lt;/i&gt;), or broad bean (&lt;i&gt;Vicia faba&lt;/i&gt;) (Dang &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2024&lt;/span&gt;; Liu &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2025&lt;/span&gt;, &lt;span&gt;2026&lt;/span&gt;; Zhang &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2025&lt;/span&gt;). We therefore conducted a series of control experiments to investigate the basis of these discrepancies and demonstrate that they arise from differences in light growth regimes, particularly the photope","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"252 2","pages":"546-552"},"PeriodicalIF":8.7,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.71446","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148701995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cell-based crop phenotyping for future climates","authors":"Sergey Shabala,&nbsp;Ping Yun,&nbsp;Zhong-Hua Chen,&nbsp;Meixue Zhou,&nbsp;Min Yu,&nbsp;Nadia Bazihizina","doi":"10.1111/nph.71397","DOIUrl":"10.1111/nph.71397","url":null,"abstract":"<p>Abiotic stress tolerance has been significantly weakened in modern crops during the domestication process. Regaining tolerance has become a critical task in light of current climate trends and their impact on global food security. Abiotic stress tolerance is an extremely complex trait and is conferred at various levels of plant functional organization and developmental stages, with regulatory mechanisms operating across multiple scales, from individual cells to tissues and the entire plant. The emergence of advanced molecular tools such as single-cell RNA sequencing and spatial omics technologies has revolutionized the field, advancing our understanding of plant responses to hostile environments. However, the implementation of this knowledge in crop breeding programmes is handicapped by the lack of appropriate phenotyping platforms. Here, we argue that current phenotyping methods may be excellent tools for functional validation of previously discovered traits but have limited predictive value in stress biology. We also propose that bridging the mismatch between omics technologies and phenotyping is the only way to account for cell-specific operation of key genes conferring stress tolerance and implementing them in breeding programmes. Some practical examples using cell-based phenotyping tools such as fluorescence dyes or electrophysiological methods are given, and current limitations and prospects of cell-based phenotyping are discussed.</p>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"252 2","pages":"575-587"},"PeriodicalIF":8.7,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.71397","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148415171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The CmABI5-CmKN1 module regulates seasonal growth and flowering in response to chilling in chrysanthemum","authors":"Tianhua Jiang,&nbsp;Chang Luo,&nbsp;Chuqi Zhang,&nbsp;Xuening Liu,&nbsp;Yahui Sun,&nbsp;Lei Liu,&nbsp;Chuyan Jiang,&nbsp;Kang Gao,&nbsp;Dongliang Chen,&nbsp;Li Cao,&nbsp;Yafei Zhao,&nbsp;Chao Ma,&nbsp;Conglin Huang","doi":"10.1111/nph.71537","DOIUrl":"10.1111/nph.71537","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 \u0000 </p><ul>\u0000 \u0000 \u0000 <li>Perennial plants have evolved complex regulatory networks that allow them to perceive environmental changes and trigger adaptive growth responses. Many perennial herbs exhibit a rosette growth habit during winter, and then undergo extension growth/stem elongation growth and flowering in the following spring. However, the mechanisms underlying this seasonal transition are still not well understood.</li>\u0000 \u0000 \u0000 <li>Here, using the perennial herb chrysanthemum (<i>Chrysanthemum morifolium</i>), we identified <i>CmKN1</i>, a class I <i>KNOTTED (KN1)-like</i> homeobox transcription factor, that mediates extension growth and flowering competence in response to prolonged chilling exposure.</li>\u0000 \u0000 \u0000 <li>The rosette growth of chrysanthemum rhizomes in late autumn coincides with downregulation of <i>CmKN1</i> expression. Overexpression of <i>CmKN1</i> promotes premature rhizome extension growth and flowering, whereas the <i>kn1</i> heterozygous mutant shows suppression of these processes. Furthermore, seasonal growth regulation involves the abscisic acid (ABA) signaling pathway. Shoot apices in the rosette state accumulate higher levels of ABA than those in the extension growth state. Notably, in response to ABA, <i>CmKN1</i> expression is downregulated by CmABI5.</li>\u0000 \u0000 \u0000 <li>Our results demonstrated that the CmABI5-CmKN1 module mediates extension growth and flowering competence in response to chilling, thereby facilitating the perennial growth habit of chrysanthemum.</li>\u0000 </ul>\u0000 \u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"252 2","pages":"724-739"},"PeriodicalIF":8.7,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148842981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The value of Arabidopsis as a model for secondary xylem research","authors":"Alicja Dolzblasz,&nbsp;Elżbieta Myśkow,&nbsp;Aleksandra Słupianek,&nbsp;Yoselin Benitez-Alfonso,&nbsp;Katarzyna Sokołowska","doi":"10.1111/nph.71403","DOIUrl":"10.1111/nph.71403","url":null,"abstract":"<p>Secondary xylem (wood) is the most abundant lignocellulosic material used by mankind. Its differentiation is ensured by a tight mechanism that regulates the expression of thousands of genes. Our knowledge of the molecular mechanisms involved in secondary xylem formation has largely been extrapolated from studies performed using the basal part of the stem and/or the hypocotyl of the model plant <i>Arabidopsis</i>. We provide an illustrated structural description of the secondary xylem from the stem and hypocotyl of <i>Arabidopsis</i> and from the model tree <i>Populus</i>. Structural descriptions, supported by literature data and anatomical images, serve as the basis for comparing <i>Arabidopsis</i> ‘woody’ structures with the secondary xylem of <i>Populus</i>, thereby enabling a discussion of their usefulness in plant research. We also outline published research that used <i>Arabidopsis</i> to study the mechanisms of secondary xylem formation and discuss the challenges associated with this approach. Secondary xylem is a heterogeneous and difficult to analyse tissue. Our article addresses the missing gaps and provides insight into structural similarities/differences between the secondary xylem of <i>Arabidopsis</i> stem and hypocotyl and that of <i>Populus</i>. The goal was to make descriptions detailed yet accessible to plant scientists, including those who are not experts in anatomy.</p>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"252 2","pages":"558-574"},"PeriodicalIF":8.7,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.71403","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148393332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}