New Phytologist最新文献

{"title":"Global peatland greenhouse gas dynamics: state of the art, processes, and perspectives","authors":"Ülo Mander,&nbsp;Maarja Öpik,&nbsp;Mikk Espenberg","doi":"10.1111/nph.20436","DOIUrl":"10.1111/nph.20436","url":null,"abstract":"<p>Natural peatlands regulate greenhouse gas (GHG) fluxes through a permanently high groundwater table, causing carbon dioxide (CO₂) assimilation but methane (CH₄) emissions due to anaerobic conditions. By contrast, drained and disturbed peatlands are hotspots for CO₂ and nitrous oxide (N₂O) emissions, while CH₄ release is low but high from drainage ditches. Generally, in low-latitude (tropical and subtropical) peatlands, emissions of all GHGs are higher than in high-latitude (temperate, boreal, and Arctic) peatlands. Their inherent dependence on the water regime makes peatlands highly vulnerable to both direct and indirect anthropogenic impacts, including climate change-induced drying, which is creating anthro-natural ecosystems. This paper presents state-of-the-art knowledge on peatland GHG fluxes and their key regulating processes, highlighting approaches to study spatio-temporal dynamics, integrated methods, direct and indirect human impacts, and peatlands' perspectives.</p>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"246 1","pages":"94-102"},"PeriodicalIF":8.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.20436","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143072637","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":"Two antagonistic gene regulatory networks drive Arabidopsis root hair growth at low temperature linked to a low-nutrient environment","authors":"Tomás Urzúa Lehuedé,&nbsp;Victoria Berdion Gabarain,&nbsp;Miguel Angel Ibeas,&nbsp;Hernán Salinas-Grenet,&nbsp;Romina Achá-Escobar,&nbsp;Tomás C. Moyano,&nbsp;Lucia Ferrero,&nbsp;Gerardo Núñez-Lillo,&nbsp;Jorge Pérez-Díaz,&nbsp;María Florencia Perotti,&nbsp;Virginia Natali Miguel,&nbsp;Fiorella Paola Spies,&nbsp;Miguel A. Rosas,&nbsp;Ayako Kawamura,&nbsp;Diana R. Rodríguez-García,&nbsp;Ah-Ram Kim,&nbsp;Trevor Nolan,&nbsp;Adrian A. Moreno,&nbsp;Keiko Sugimoto,&nbsp;Norbert Perrimon,&nbsp;Karen A. Sanguinet,&nbsp;Claudio Meneses,&nbsp;Raquel L. Chan,&nbsp;Federico Ariel,&nbsp;Jose M. Alvarez,&nbsp;José M. Estevez","doi":"10.1111/nph.20406","DOIUrl":"10.1111/nph.20406","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 </p><ul>\u0000 \u0000 <li>Root hair (RH) cells can elongate to several hundred times their initial size, and are an ideal model system for investigating cell size control. Their development is influenced by both endogenous and external signals, which are combined to form an integrative response. Surprisingly, a low-temperature condition of 10°C causes increased RH growth in <i>Arabidopsis</i> and in several monocots, even when the development of the rest of the plant is halted.</li>\u0000 \u0000 <li>Previously, we demonstrated a strong correlation between RH growth response and a significant decrease in nutrient availability in the growth medium under low-temperature conditions. However, the molecular basis responsible for receiving and transmitting signals related to the availability of nutrients in the soil, and their relation to plant development, remain largely unknown.</li>\u0000 \u0000 <li>We have discovered two antagonic gene regulatory networks (GRNs) controlling RH early transcriptome responses to low temperature. One GNR enhances RH growth and it is commanded by the transcription factors (TFs) <i>ROOT HAIR DEFECTIVE 6</i> (RHD6), <i>HAIR DEFECTIVE 6-LIKE 2 and 4</i> (RSL2-RSL4) and a member of the homeodomain leucine zipper (HD-Zip I) group I 16 (AtHB16). On the other hand, a second GRN was identified as a negative regulator of RH growth at low temperature and it is composed by the trihelix TF <i>GT2-LIKE1</i> (GTL1) and the associated DF1, a previously unidentified MYB-like TF (AT2G01060) and several members of HD-Zip I group (<i>AtHB3, AtHB13, AtHB20, AtHB23</i>).</li>\u0000 \u0000 <li>Functional analysis of both GRNs highlights a complex regulation of RH growth response to low temperature, and more importantly, these discoveries enhance our comprehension of how plants synchronize RH growth in response to variations in temperature at the cellular level.</li>\u0000 </ul>\u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"245 6","pages":"2645-2664"},"PeriodicalIF":8.3,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143072556","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":"Towards a global understanding of tree mortality","authors":"International Tree Mortality Network","doi":"10.1111/nph.20407","DOIUrl":"10.1111/nph.20407","url":null,"abstract":"<p>Rates of tree mortality are increasing globally, with implications for forests and climate. Yet, how and why these trends vary globally remain unknown. Developing a comprehensive assessment of global tree mortality will require systematically integrating data from ground-based long-term forest monitoring with large-scale remote sensing. We surveyed the metadata from 466 865 forest monitoring plots across 89 countries and five continents using questionnaires and discuss the potential to use these to estimate tree mortality trends globally. Our survey shows that the area monitored has increased steadily since 1960, but we also identify many regions with limited ground-based information on tree mortality. The integration of existing ground-based forest inventories with remote sensing and modelling can potentially fill those gaps, but this requires development of technical solutions and agreements that enable seamless flows of information from the field to global assessments of tree mortality. A truly global monitoring effort should promote fair and equitable collaborations, transferring funding to and empowering scientists from less wealthy regions. Increasing interest in forests as a natural climate solution, the advancement of new technologies and world-wide connectivity means that now a global monitoring system of tree mortality is not just urgently needed but also possible.</p>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"245 6","pages":"2377-2392"},"PeriodicalIF":8.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.20407","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143071724","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":"HOS15 impacts DIL9 protein stability during drought stress in Arabidopsis","authors":"Shah Zareen,&nbsp;Akhtar Ali,&nbsp;Junghoon Park,&nbsp;Sang-Mo Kang,&nbsp;In-Jung Lee,&nbsp;Jose M. Pardo,&nbsp;Dae-Jin Yun,&nbsp;Zheng-Yi Xu","doi":"10.1111/nph.20398","DOIUrl":"10.1111/nph.20398","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 </p><ul>\u0000 \u0000 <li>HIGH EXPRESSION OF OSMOTICALLY RESPONSIVE GENE 15 (HOS15) acts as a substrate receptor of E3 ligase complex, which plays a negative role in drought stress tolerance. However, whether and how HOS15 participates in controlling important transcriptional regulators remains largely unknown.</li>\u0000 \u0000 <li>Here, we report that HOS15 physically interacts with and tightly regulates DROUGHT-INDUCED LIKE 19 (DIL9) protein stability. Moreover, application of exogenous abscisic acid (ABA) stabilizes the interaction between DIL9 and HOS15, leading to ABA-induced proteasomal degradation of DIL9 by HOS15. Genetic analysis revealed that DIL9 functions downstream to HOS15 and that the drought tolerance of <i>hos15-2</i> plants was impaired in <i>dil9/hos15</i> double mutants.</li>\u0000 \u0000 <li>Notably, DIL9 is directly associated with the promoter regions of <i>ABF</i> transcription factors and facilitates their expression, which is pivotal in enhancing ABA-dependent drought tolerance.</li>\u0000 \u0000 <li>Collectively, these findings demonstrate that HOS15 consistently degrades DIL9 under normal condition, while stress (drought/ABA) promotes the DIL9 activity for binding to the promoter regions of <i>ABFs</i> and positively regulates their expression in response to dehydration.</li>\u0000 </ul>\u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"245 6","pages":"2553-2568"},"PeriodicalIF":8.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143069090","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":"Leaf carbon monoxide emissions under different drought, heat, and light conditions in the field","authors":"Jonathan D. Muller,&nbsp;Rafat Qubaja,&nbsp;Eugene Koh,&nbsp;Rafael Stern,&nbsp;Yasmin L. Bohak,&nbsp;Fyodor Tatarinov,&nbsp;Eyal Rotenberg,&nbsp;Dan Yakir","doi":"10.1111/nph.20424","DOIUrl":"10.1111/nph.20424","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 </p><ul>\u0000 \u0000 <li>Carbon monoxide (CO) is known primarily as a globally emitted by-product of incomplete combustion from the industry and biomass burning. However, CO is also produced in living plants and acts as a stress-signalling molecule in animals and plants. While CO emissions from soil and litter decomposition have been studied, research on the CO flux from living vegetation is scarce, particularly under field conditions.</li>\u0000 \u0000 <li>Here, we present a year-long field study on the effects of light, heat, and seasonal drought on leaf CO production and flux using automated twig chambers on mature <i>Pinus halepensis</i> trees grown under summer-droughted and nondroughted (irrigated) conditions.</li>\u0000 \u0000 <li>We found CO buildup in drought-stressed tree leaves, with emissions linked to the heat-controlled biogenic production of CO rather than to photodegradation. In irrigated trees, CO fluxes occurred through open stomata, whereas in droughted trees, CO buildup overcame stomatal closure to result in a flux.</li>\u0000 \u0000 <li>The results support the role of CO in heat stress response and the likely mitigation of damage induced by reactive oxygen species. We highlight the need for further research into the mechanistic basis for CO flux from living plants.</li>\u0000 </ul>\u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"245 6","pages":"2439-2450"},"PeriodicalIF":8.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143069122","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":"GS2 cooperates with IPA1 to control panicle architecture","authors":"Yueying Wang,&nbsp;Yang Lv,&nbsp;Yi Wen,&nbsp;Junge Wang,&nbsp;Peng Hu,&nbsp;Kaixiong Wu,&nbsp;Bingze Chai,&nbsp;Shuxian Gan,&nbsp;Jialong Liu,&nbsp;Yue Wu,&nbsp;Lixin Zhu,&nbsp;Nannan Dong,&nbsp;Yiqing Tan,&nbsp;Hao Wu,&nbsp;Guangheng Zhang,&nbsp;Li Zhu,&nbsp;Deyong Ren,&nbsp;Qiang Zhang,&nbsp;Yuexing Wang,&nbsp;Qian Qian,&nbsp;Jiang Hu","doi":"10.1111/nph.20412","DOIUrl":"10.1111/nph.20412","url":null,"abstract":"<p>\u0000 </p>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"245 6","pages":"2726-2743"},"PeriodicalIF":8.3,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.20412","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143069075","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":"An OsRPP13 protein contributes to rice resistance against herbivorous insects","authors":"Feilong Ma,&nbsp;Jiaoyang Chen,&nbsp;Zhipeng Lu,&nbsp;Zhuo Wang,&nbsp;Feixiang Ma,&nbsp;Siqi Zhao,&nbsp;Denan Wu,&nbsp;Xianhe Guo,&nbsp;Man Qi,&nbsp;Gongyi Song,&nbsp;Jiaran Zhao,&nbsp;Mengtian Wen,&nbsp;Yuan Wang,&nbsp;Meng Zhang,&nbsp;Yiting Guo,&nbsp;Xinyuan Xiao,&nbsp;Yilian Zhou,&nbsp;Xinyao Xu,&nbsp;Jiaqi Zhang,&nbsp;Qinzheng Wang,&nbsp;Zhihuan Tao,&nbsp;Bo Sun,&nbsp;Su Chen","doi":"10.1111/nph.20427","DOIUrl":"10.1111/nph.20427","url":null,"abstract":"&lt;p&gt;Rice (&lt;i&gt;Oryza sativa&lt;/i&gt;) is one of the world's most vital crops. Rice production faces significant threats from insect pests such as the brown planthopper (&lt;i&gt;Nilaparvata lugens&lt;/i&gt;, BPH) and the striped stem borer (&lt;i&gt;Chilo suppressalis&lt;/i&gt;, SSB) (Deng &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2024&lt;/span&gt;; Kuai &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2024&lt;/span&gt;). The piercing-sucking insect BPH directly damages rice plants by extracting phloem sap and transmitting various viral diseases. In field settings, severe BPH outbreaks can lead to complete crop desiccation, resulting in ‘hopperburn’. The chewing insect SSB feeds on newly formed tillers and stems, causing ‘dead hearts’ and ‘white heads’. R proteins such as BPH14, BPH9, and OsLRR2 play a critical role in insect resistance (Guo &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2023&lt;/span&gt;). While several R genes conferring BPH resistance have been cloned, there are no rice germplasms resistant to SSB. This study identifies a novel R gene, &lt;i&gt;OsRPP13&lt;/i&gt;, that positively regulates rice resistance to BPH by regulating flavonoids and hydrogen peroxide levels. Additionally, the resulting increase in jasmonic acid (JA) positively contributes to resistance against SSB. These findings provide valuable insights into the mechanisms underlying insect resistance conferred by R genes and present a potential avenue for breeding insect-resistant rice cultivars.&lt;/p&gt;&lt;p&gt;In this study, we first analyzed the expression profile of &lt;i&gt;OsRPP13&lt;/i&gt; through quantitative reverse transcription polymerase chain reaction assays. Primers refer to Supporting Information Table S1. Various tissues including the leaf blade, stem, root, and leaf sheath were analyzed, revealing that &lt;i&gt;OsRPP13&lt;/i&gt; was mainly expressed in the leaf sheath, which is the primary location for BPH feeding (Fig. 1a). A further analysis unveiled drastic changes in &lt;i&gt;OsRPP13&lt;/i&gt; expression following BPH and SSB infestation (Fig. 1b), suggesting the gene's vital role in the interaction between rice and herbivorous insects. Subcellular localization analysis showed that OsRPP13–YFP fusion protein both in the cytoplasm and in the nucleus of rice protoplasts (Fig. S1). Then, we utilized agrobacterium-mediated plant transformation and CRISPR-Cas9 technology to create transgenic &lt;i&gt;OsRPP13&lt;/i&gt; plants. Two &lt;i&gt;OsRPP13&lt;/i&gt; overexpression lines (OsRPP13OE) (Fig. 1c) and two &lt;i&gt;OsRPP13&lt;/i&gt; knockout lines (OsRPP13KO), which have a one-base insertion and a two-base deletion, respectively (Fig. 1d), were selected to investigate the impact on rice resistance to BPH and SSB. We employed various methods to characterize the phenotypic response of &lt;i&gt;OsRPP13&lt;/i&gt; transgenic plants to BPH infestation. While OsRPP13OE lines exhibited a significantly enhanced resistance (Fig. 1e), &lt;i&gt;OsRPP13&lt;/i&gt; knockout lines were more susceptible to BPH than the wild-type (WT) (Fig. 1f). Compared with the WT, rice seeding rates were significantly enhanced in OsRPP13OE plants, but decreased in OsRPP13KO plants (Fig. S2). To determine the effects of &lt;","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"246 1","pages":"28-32"},"PeriodicalIF":8.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.20427","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143056345","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":"Phylogenetic and biochemical drivers of plant species variation in organic compound hydrogen stable isotopes: novel mechanistic constraints","authors":"Jochem Baan,&nbsp;Meisha Holloway-Phillips,&nbsp;Daniel B. Nelson,&nbsp;Jurriaan M. de Vos,&nbsp;Ansgar Kahmen","doi":"10.1111/nph.20430","DOIUrl":"10.1111/nph.20430","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 \u0000 </p><ul>\u0000 \u0000 \u0000 <li>Significant variation in plant organic compound hydrogen stable isotope (δ²H) values among species from a single location suggests species biochemistry diversity as a key driver. However, the biochemical mechanisms and the biological relevance behind this species-specific δ²H variation remain unclear.</li>\u0000 \u0000 \u0000 <li>We analyzed δ²H values of cellulose and <i>n</i>-alkanes across 179 eudicot species in a botanical garden sampled in 2019, and cellulose, <i>n</i>-alkanes, fatty acids and phytol δ²H values from 56 eudicot species sampled in 2020. We utilized the observed species variation in δ²H values to determine phylogenetic structure and mechanistic constraints for biochemical ²H-fractionation.</li>\u0000 \u0000 \u0000 <li>A strong phylogenetic signal in lipid compound δ²H values implies that the drivers of species variation in lipid δ²H values are evolutionarily conserved. By contrast, species variation in cellulose δ²H values was not strongly linked to phylogeny. Generally low-explanatory power of relationships between δ²H values of different compounds (<i>R</i>² &lt; 0.26) implies nonubiquitous drivers of species variation in plant organic compound δ²H values.</li>\u0000 \u0000 \u0000 <li>Historically, variable biochemical ²H-fractionation was often attributed to δ²H values of H incorporated from NADPH. Instead, the results from this study suggest that species variation in biochemical ²H-fractionation largely occurs independently within biosynthetic pathways. For lipids, these mechanisms appear strongly linked to evolutionary history.</li>\u0000 </ul>\u0000 \u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"246 1","pages":"113-130"},"PeriodicalIF":8.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143056346","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":"Blocking constitutive autophagy rescues the loss of acquired heat resistance in Arabidopsis fes1a","authors":"Xuezhi Li,&nbsp;Tong Su,&nbsp;Xiaofeng Wang,&nbsp;Yan Liu,&nbsp;Jingjing Ge,&nbsp;Panfei Huo,&nbsp;Yiwu Zhao,&nbsp;Tongtong Wang,&nbsp;Hongbin Yu,&nbsp;Meijie Duan,&nbsp;Yuebin Jia,&nbsp;Xianpeng Yang,&nbsp;Pingping Wang,&nbsp;Qingqiu Gong,&nbsp;Jian Liu,&nbsp;Changle Ma","doi":"10.1111/nph.20393","DOIUrl":"10.1111/nph.20393","url":null,"abstract":"<div>\u0000 \u0000 <p>\u0000 </p><ul>\u0000 \u0000 <li>High temperature is one of several major abiotic stresses that can cause substantial loss of crop yields. Heat shock proteins (HSPs) are key components of heat stress resistance. Mutation of FES1A, an auxiliary molecular chaperone of HSP70, leads to defective acquired thermotolerance. Autophagy is a positive regulator of basal thermotolerance and a negative regulator of heat stress memory, but its function in acquired thermotolerance is unclear.</li>\u0000 \u0000 <li>We found that blocking constitutive autophagy rescued the heat sensitivity of <i>fes1a</i> in <i>Arabidopsis thaliana</i>. Immunoblot and proteomic analyses showed that the rescue was not due to increased HSP levels. Instead, proteomic analysis and confocal microscopy studies revealed that knocking out the core autophagy-related (<i>ATG</i>) genes leads to accumulation of peroxisomes, thus upregulating the metabolic pathways within the peroxisomes.</li>\u0000 \u0000 <li>Accumulation of peroxisomes promotes both reactive oxygen species scavenging and indole-3-acetic acid (IAA) production in <i>atg7 fes1a</i>. Overexpression of ABCD1/PXA1/CTS, a peroxisomal ATP-binding cassette transporter, in <i>atg7 fes1a</i> leads to abnormal peroxisomal function and subsequently thermosensitivity. Moreover, we found that exogenous application of indole-3-butyric acid, IAA or naphthalene-1-acetic acid rescued <i>fes1a</i> heat sensitivity.</li>\u0000 \u0000 <li>We propose that autophagy is detrimental to the survival of the <i>fes1a</i> mutant, which has acquired thermosensitivity.</li>\u0000 </ul>\u0000 </div>","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"245 6","pages":"2569-2583"},"PeriodicalIF":8.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143057034","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":"Rigorous mathematical modeling and physiological experimentation reveal that Ralstonia wilt pathogens consume an in planta diet of amino acids with a dash of sugar","authors":"Corri D. Hamilton,&nbsp;Tiffany M. Lowe-Power","doi":"10.1111/nph.20417","DOIUrl":"10.1111/nph.20417","url":null,"abstract":"&lt;p&gt;How does &lt;i&gt;Ralstonia&lt;/i&gt; acquire sufficient carbon for its massive &lt;i&gt;in planta&lt;/i&gt; reproduction? To answer questions such as this, bacteriologists typically turn to our favorite approaches, bioassays with metabolic mutants, comparative genomics, gene expression analysis, and occasionally, chemistry, if we must. Molecular genetics provide evidence that sugars (primarily sucrose and glucose) partially support &lt;i&gt;Ralstonia&lt;/i&gt;'s growth &lt;i&gt;in planta&lt;/i&gt; (Jacobs &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2012&lt;/span&gt;; Lowe-Power &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2018a&lt;/span&gt;; Gerlin &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2021&lt;/span&gt;; Hamilton &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2021&lt;/span&gt;). However, these mutants still wilt plants at nearly wild-type rates. Could amino acids and organic acids be the missing factor? Genetically blocking amino acid and organic acid assimilation is more complex than sugar assimilation, leaving the role of alternative carbon sources untested.&lt;/p&gt;&lt;p&gt;To solve this mystery, Caroline Baroukh &lt;i&gt;et al&lt;/i&gt;. at the Laboratoire des Interactions Plantes Microorganismes (LIPME) part of the National Research Institute for Agriculture, Food and the Environment (INRAE), Toulouse, France, have adopted a strategic, stepwise approach integrating quantitative physiology and modeling (Fig. 1). Gerlin &lt;i&gt;et al&lt;/i&gt;. (&lt;span&gt;2021&lt;/span&gt;) precisely quantified the physiological variables of bacterial wilt disease, measuring concentrations of dozens of metabolites over an 8-day infection course using nuclear magnetic resonance (NMR) metabolomics. They found that tomato xylem sap contains &lt;i&gt;c&lt;/i&gt;. 7–11 mM carbon and 2–4 mM organic nitrogen, with many amino acids more abundant than sugars. Notably, glutamine is present at &lt;i&gt;c&lt;/i&gt;. 3.3 mM &lt;i&gt;in planta&lt;/i&gt; and decreases during infection. Baroukh &lt;i&gt;et al&lt;/i&gt;. then investigated &lt;i&gt;Ralstonia&lt;/i&gt;'s trophic preferences for the putative xylem sap carbon sources (Baroukh &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2022&lt;/span&gt;). Unlike typical bacteriologists who investigate nutrient utilization solely with bacterial growth assays in minimal media, Baroukh &lt;i&gt;et al&lt;/i&gt;. continued using NMR metabolomics to analyze the rate at which &lt;i&gt;Ralstonia&lt;/i&gt; assimilated each nutrient from culture media, both individually and in pairs. Here, they discovered that &lt;i&gt;Ralstonia&lt;/i&gt; simultaneously assimilates distinct carbon sources, lacking the ‘catabolite repression’ mechanism sometimes seen in bacteria. Thus, &lt;i&gt;Ralstonia&lt;/i&gt; are flexible heterotrophs – not picky eaters.&lt;/p&gt;&lt;p&gt;A key innovation of the 2024 study in &lt;i&gt;New Phytologist&lt;/i&gt; is the development of a synthetic xylem-mimicking medium (XMM) that mirrors the carbon composition of tomato xylem sap (Baroukh &lt;i&gt;et al&lt;/i&gt;., &lt;span&gt;2025&lt;/span&gt;). XMM allows for highly controlled studies of bacterial behavior in conditions similar to those in the xylem. Remarkably, the authors show that the complexity of tomato xylem sap can be simulated with just 13 substrates, including glutamine, asparagine, sucrose, and glucose. XMM supported bacterial growth simila","PeriodicalId":214,"journal":{"name":"New Phytologist","volume":"246 1","pages":"5-7"},"PeriodicalIF":8.3,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/nph.20417","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143056343","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}