Tree physiology最新文献

{"title":"The aridity influence on oxygen isotopes recorded in tree rings.","authors":"Kinzie Bailey, Paul Szejner, Brandon Strange, Rhiannon Nabours, Russell K Monson, Jia Hu","doi":"10.1093/treephys/tpaf044","DOIUrl":"https://doi.org/10.1093/treephys/tpaf044","url":null,"abstract":"<p><p>The stable isotopes of oxygen in wood cellulose (δ18Ocell) have been widely used to reconstruct historical source water use in trees or changes in atmospheric humidity. However, in many cases, the δ18O of source water use is assumed to reflect that of precipitation, which is often not the case in semi-arid to arid ecosystems where trees use deeper and older water from previous precipitation events (or even groundwater). Furthermore, the degree to which δ18Ocell reflects source water and atmospheric aridity depends on pex, normally defined as the proportion of oxygen atoms that exchange between isotopically enriched carbohydrates from the leaf and unenriched xylem water during cellulose synthesis. Many studies treat pex as a constant. However, pex can only be estimated with direct measurements of δ18Ocell and the δ18O of tree source water and sucrose. Additionally, other physiological mechanisms (e.g. photosynthate translocation) can alter the isotopic signal before cellulose is produced. Thus, determining this \"apparent pex\" (apex; which includes photosynthate translocation plus the exchange of oxygen atoms during cellulose synthesis), can be difficult. In this study, we collected δ18O of xylem water and δ18O of wood cellulose from seven stands of Ponderosa pine situated at the northern boundary of the North American Monsoon climate system to assess how potential variability in apex influenced how source water and aridity were recorded in δ18Ocell. We compared measured and modeled values of δ18Ocell and found that more arid sites under-represented the vapor pressure deficit signal in cellulose while wetter sites over-represented the vapor pressure deficit signal in cellulose. We also found that apex varied as a function of site aridity, where low precipitation and high vapor pressure deficit led to high apex, while high precipitation and low vapor pressure deficit led to low apex. Future studies can use our emerging understanding of the aridity-apex relationship in different portions of the annual ring to better disentangle the source water and VPD signals in cellulose, particularly for regions such as the North American Monsoon region.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796447","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 physiological and endophytic microbial community characteristics and interactions of different scions grafted onto Malus sieversii.","authors":"Huanhuan Zhang, Dongdong Yao, Hossam Salah Mahmoud Ali, Guangxin Zhang, Xujiao Li, Jingshan Xi, Yingchi Liang, Li Shao, Fengyun Zhao, Songlin Yu, Kun Yu","doi":"10.1093/treephys/tpaf042","DOIUrl":"https://doi.org/10.1093/treephys/tpaf042","url":null,"abstract":"<p><p>Endophytic microbial communities in scion leaves substantially impact the growth efficiency of apple trees (Malus × domestica Borkh.); however, the underlying mechanisms remain underexplored. Herein, we grafted three varieties-Malus sieversii, Hanfu, and Fuji-onto M. sieversii rootstocks and employed high-throughput sequencing technology to investigate how physiological traits of scion leaves influence endophytic microbiota and apple tree growth. Compared to the M. sieversii scion, the aboveground (+49.28%) and root (+62.77%) biomass of juvenile trees grafted with the Hanfu scion significantly increased, with the net photosynthetic rate and stomatal conductance rising by 20.40% and 42.26%, respectively. Additionally, the leaves of the Hanfu scion exhibited a significant increase in sucrose synthase activity and carbon accumulation compared to the M. sieversii and Fuji scions, while the carbon content and carbon-to-nitrogen ratio significantly decreased. Furthermore, through 16S rDNA and ITS high-throughput sequencing, we found that the diversity and abundance of endophytic bacteria and fungi in the leaves of the Hanfu scion were higher than in the M. sieversii and Fuji scions. Hanfu scion leaves were predominantly enriched with the phyla Firmicutes and Ascomycota and the genus Salinicoccus. A close association was observed between leaf endophytic bacterial and fungal communities and physiological traits, with particularly significant correlations in the fungal communities. Parameters such as leaf intercellular carbon dioxide concentration, chlorophyll b content, carbon-to-nitrogen ratio, and carbon accumulation were implicated in enriching dominant endophytic microbial phyla and genera. Through partial least squares structural equation models, we confirmed that leaf photosynthetic properties and carbon and nitrogen metabolism significantly affect leaf carbon and nitrogen accumulation through the regulation of endophytic fungal diversity, thereby affecting apple tree growth. In conclusion, the interaction between leaf physiological properties of different scion varieties and the diversity and composition of endophytic microbial communities influences apple tree growth.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796442","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":"Increasing air-filled vessels has little influence on vulnerability to drought-induced embolism in two species with long maximum xylem vessel length but low vessel connectivity.","authors":"Chris M Smith-Martin, Kate M Johnson, Shelley Urquhart, Madeline R Carins-Murphy, Celia M Rodriguez-Dominguez, Christopher Lucani, Déborah Corso, Brendan Choat, Alice Gauthey, Laura Victoria Perez-Martinez, Scott A M McAdam, Leland K Werden, Timothy J Brodribb","doi":"10.1093/treephys/tpaf041","DOIUrl":"https://doi.org/10.1093/treephys/tpaf041","url":null,"abstract":"<p><p>Perennial woody plants accumulate native xylem embolisms over time. However, whether this makes the water transport system more vulnerable to drought-induced dysfunction as the percentage of gas-filled vessels increases is unclear. We tested whether increasing the proportion of open (air-filled) vessels changes the overall embolism vulnerability in stems of angiosperm species with long maximum vessel lengths but relatively low vessel connectivity. Using optical vulnerability curves, we measured xylem vulnerability of 57 branches ranging in length from ~ 10 to over 300 cm, from two adult trees (Acacia mearnsii and Eucalyptus globulus) known to have long maximum vessel length (> 75 cm) but low vessel connectivity. The fraction of open vessels at different branch lengths was estimated by staining open vessels under suction and with X-ray micro-computed tomography (μCT). To relate this to native field conditions, the percentage of pre-existing native embolisms was measured with μCT on a different set of branches. Our results show that even when a large proportion (> 25%) of open (air-filled) vessels are present, the xylem-embolism thresholds (water potential at 12% (P12), 50% (P50), and 88% (P88) embolized xylem area) resemble those of branches with no open vessels. Scanning of native embolism with μCT revealed 10% (E. globulus) and 20% (A. mearnsii) native embolism under natural conditions. We conclude that even when approximately one-quarter of vessels are air-filled, there is no discernable effect on the overall xylem vulnerability of stem segments with long vessels and low vessel connectivity. Xylem vulnerability to embolism among all the branches measured from each of the two trees was relatively homogeneous with a ~ 10-20% variation. Our findings also suggest that the presence of pre-existing native embolisms, at the percentages observed in the field (<25%), would not increase vulnerability to xylem embolism in these species with largely isolated individual xylem vessels.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143796438","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":"Phosphorus deficiency suppresses the trans-zeatin riboside accumulation by up-regulating CeIPT5, promoting root elongation and phosphorus absorption efficiency of Casuarina equisetifolia.","authors":"Lijuan Jiang, Hua Yang, Yunshuang Du, Zhaoliang Zheng, Shanshan Ding, Xinyan Zhang, Xingliang Yao, Gongfu Ye, Jun Su, Jian Li","doi":"10.1093/treephys/tpaf038","DOIUrl":"https://doi.org/10.1093/treephys/tpaf038","url":null,"abstract":"<p><p>Phosphorus (P) deficiency is critical to the renewal barrier of she-oak (Casuarina equisetifolia), an important tree species used for coastal protection. However, the response of she-oak to P deficiency remains unclear. In this study, we compared the phenotypes of two she-oak cultivars, the P deficiency-sensitive 'Chihu219' and the insensitive 'Chihu397', and found that P deficiency significantly increased root growth, P concentration and P absorption efficiency (PAE) in Chihu219, but not in Chihu397. We also analyzed the transcriptome and metabolome of these cultivars under different P conditions and showed that trans-zeatin riboside (tZR) levels were highly suppressed by P deficiency in Chihu219, but not in Chihu397. Furthermore, exogenous tZR suppressed both root P concentration and PAE while promoting phosphorus use efficiency (PUE). We also identified CeIPT5 (isopentenyltransferase 5) as a key regulatory gene of tZR biosynthesis and found that its expression was more highly induced by P deficiency in Chihu219 than in Chihu397. We also showed that overexpression of CeIPT5 in insensitive she-oak lines reduced tZR concentration and increased root P concentration compared to the vector control. Taken together, P deficiency can greatly reduce tZR accumulation in P deficiency-insensitive she-oak at least by activating the tZR accumulation regulatory gene, CeIPT5, thereby promoting root elongation and P concentration. This study not only provides a genetic basis for enhancing PAE in woody plants, but also establishes a theoretical basis for optimizing root structure and improving nutrient utilization efficiency, thereby promoting sustainable forestry development.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143754518","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":"Correction to: Transcriptomic analysis reveals potential roles of polyamine and proline metabolism in waterlogged peach roots inoculated with Funneliformis mosseae and Serendipita indica.","authors":"","doi":"10.1093/treephys/tpaf040","DOIUrl":"https://doi.org/10.1093/treephys/tpaf040","url":null,"abstract":"","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":"45 4","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143744039","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":"Fine root respiration in Quercus rubra (L.) aligns with the economics trade-offs in bi-dimensional root trait space.","authors":"E L Shedd, M A Cavaleri, C Külheim, A J Burton","doi":"10.1093/treephys/tpaf024","DOIUrl":"10.1093/treephys/tpaf024","url":null,"abstract":"<p><p>Plant economic theory argues that growth strategies maximize either the rate or longevity of return per resource investment in a unidimensional trade-off. Belowground trade-offs may not mimic those aboveground due to soil resource heterogeneity, different physical constraints imposed by the shape of roots compared with leaves and fungal symbioses, and often multiple dimensions of variation are found. Root respiration represents a substantial carbon flux out of forest ecosystems, but its placement in these trade-offs is unclear, and its incorporation into carbon cycle models is limited by available data. Most research on root traits has focused on interspecific variability, but here, we investigated whether trade-offs among one species' populations align with those between species by sampling Quercus rubra (L.) populations along a Midwest, USA latitudinal gradient. Across populations, we assessed whether fine root traits follow uni- or multidimensional trade-offs and how these axes relate to root respiration. Respiration rates, morphological traits and root nitrogen were measured on excised fine roots at 14 sites, spanning a wide variety of environmental conditions, and then analyzed for trade-off axes. We uncovered substantial root trait variation among Q. rubra populations that aligned with two distinct trade-offs, one between branching intensity (BI) and average diameter and a second with root tissue density on one end and specific root length, root nitrogen concentration and root specific respiration (RSR) on the other. Reliance on ectomycorrhizal fungi, which colonize root tips, may be a possible explanation for the first axis, with higher BI representing more collaboration. Along the latter axis, RSR increased with root nitrogen concentration and decreased with root tissue density. These results support a similar bidimensional trait space between Q. rubra populations to that between species, with an economics trade-off that might be a useful predictor of the fine root respiration carbon flux.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143450389","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":"Estimation of mesophyll conductance in Ginkgo biloba from the PSII redox state using a machine learning approach.","authors":"Jimei Han, Lehao Li, Xin Yang, Zihan Wei, Xina Su, Fuliang Cao, Yuxuan Meng, Yang Wu, Tingting Dai, Guibin Wang","doi":"10.1093/treephys/tpaf021","DOIUrl":"10.1093/treephys/tpaf021","url":null,"abstract":"<p><p>Mesophyll conductance (gm) has been proved to be one of the important factors limiting photosynthesis and thus affects the estimation of plant productivity and terrestrial carbon balance. However, beyond the leaf scale, gm is usually assumed to be infinite because of the unavailability of the estimating technology. In this study, we first verified the important role of gm on photosynthesis by utilizing a wide range of ginkgo (Ginkgo biloba L.) families. Then, the dataset was adopted to establish a random forest-based gm estimation approach with the drivers being selected under the guidance of several mechanistic models (e.g. Farquhar, von Caemmerer, Berry model, the mechanistic light reaction model of photosynthesis). This model exhibited high predictive accuracy, utilizing both the measured fraction of open reaction centers in PSII (qL) (R2 = 0.71, RMSE = 0.008) and the estimated qL (R2 = 0.70, RMSE = 0.008) as inputs. Since qL, a key physiological driver in the model, can be obtained from chlorophyll fluorescence of PSII (SIFPSII) using the open-closed (OC) redox model of photosynthetic electron transport, this leaf-scale model could potentially be applied beyond the leaf scale, provided that environmental data are available. Direct measurements also confirmed the close relationship between qL and gm under ambient CO2 concentration and saturated light conditions. Our findings pave the way for additional attempts to estimate gm across a variety of scales.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143743919","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":"How phenology interacts with frost tolerance in Southeastern Himalayan Rhododendron species.","authors":"Hongyan Jin, Xiaoqing Yin, Yue Qi, Jurriaan M de Vos, Hang Sun, Christian Körner, Yang Yang","doi":"10.1093/treephys/tpaf036","DOIUrl":"https://doi.org/10.1093/treephys/tpaf036","url":null,"abstract":"<p><p>The frost resistance of new foliage and flowers and their relationship with the phenology of leaf-out and flowering are essential for explaining plant species distribution in seasonally cold climates. In this study, we performed a congeneric, elevational comparison of phenology with frost resistance in evergreen Rhododendron species in the Southeastern Himalayas. A comparison of the microclimate with long-term meteorological records of low temperature extremes permitted the calculation of a realistic, long-term margin of safety for 12 Rhododendron species. Surprisingly, frost resistance and phenological events were matching for leaf-out time (not flowering) in higher elevation species only. Flower-leaf sequence (FLS) and frost resistance were linked for species at higher elevation and the earliest flowering species at lower elevation only. Despite a selection of FLS by elevation, flowers (including petals, filaments, and ovaries) were still prone to frost damage during the early growing season at both lower and higher elevations, while new leaves were generally safe on long-term scales, regardless of phenology and elevation. In contrast to lower montane elevation, where severe frost is rare in spring, treeline elevation species maintain safety margins over centennial time-scales by adjusting leaf-out phenology. Our data show an evolutionary priority of leaf survival over flower survival. Both, physiological acclimation and phylogenetic components contribute to these adjustments. Rare extreme frost events restrict the upper range limit of the examined Rhododendron species by affecting new foliage. It is essential to know the actual temperature extremes at organ level rather than relying on weather station records.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143721602","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":"Physiological and Molecular Responses of Poplar to Salt Stress and Functional Analysis of PagGRXC9 to Salt Tolerance.","authors":"Jiechen Wang, Changjun Ding, Congcong Cui, Jiaqi Song, Guangxin Ji, Nan Sun, Siyue Qi, Jie Li, Zhiru Xu, Huihui Zhang","doi":"10.1093/treephys/tpaf039","DOIUrl":"https://doi.org/10.1093/treephys/tpaf039","url":null,"abstract":"<p><p>Soil salinization is increasingly recognized as a critical environmental challenge that significantly threatens plant survival and agricultural productivity. To elucidate the mechanism of salt resistance in poplar，physiological and transcriptomic analysis were conducted on 84 K poplar (Populus alba × P. glandulosa) under varying salt concentrations (0, 100, 200, and 300 mM NaCl). As salt levels increased, observable damage to poplar progressively intensified. Differentially expressed genes (DEGs) under salt stress were primarily enriched in photosynthesis, redox activity, and glutathione metabolism pathways. Salt stress reduced chlorophyll content and net photosynthetic rate, accompanied by the downregulation of photosynthesis-related genes. 300 mM NaCl significantly inhibited the photochemical activity of photosystems. The higher photochemical activity under 100 and 200 mM NaCl was attributed to the activated PGR5-CEF photoprotective mechanism. However, the NDH-CEF was inhibited under all salt levels. Salt stress led to the ROS accumulation, activating the ASA-GSH cycle and antioxidant enzymes to mitigate oxidative damage. Weighted gene co-expression network analysis (WGCNA) showed that five photosynthesis-related hub genes (e.g., FNR and TPI) were down-regulated and nine antioxidant-related hub genes (e.g., GRX, GPX, and GST) were up-regulated under salt stress condition. PagGRXC9 encodes glutaredoxin and was found to be differentially expressed during the salt stress condition. Functional studies showed that overexpressing PagGRXC9 enhanced salt tolerance in yeast, and in poplar, it improved growth, FV/FM, NPQ values, and resistance to H2O2-induced oxidative stress under salt stress. This study constructed the photosynthetic and antioxidant response network for salt stress in poplar, revealing that PagGRXC9 enhances salt tolerance by reducing photoinhibition and increasing antioxidant capacity. These findings provide valuable insights for breeding salt-tolerant forest trees.</p>","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143721622","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":"Dendrometers -What are they good for?","authors":"Sanna Sevanto","doi":"10.1093/treephys/tpaf035","DOIUrl":"https://doi.org/10.1093/treephys/tpaf035","url":null,"abstract":"","PeriodicalId":23286,"journal":{"name":"Tree physiology","volume":" ","pages":""},"PeriodicalIF":3.5,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143721599","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}