Botanical Studies最新文献

{"title":"Correction: Chromosome number variation and phylogenetic divergence of East Asian Cirsium sect. Onotrophe subsect. Nipponocirsium (Compositae), with a new species from Taiwan.","authors":"Chih-Yi Chang, Pei-Chun Liao, Hsy-Yu Tzeng, Junko Kusumi, Zhi-Hui Su, Yen-Hsueh Tseng","doi":"10.1186/s40529-025-00458-y","DOIUrl":"10.1186/s40529-025-00458-y","url":null,"abstract":"","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"12"},"PeriodicalIF":3.4,"publicationDate":"2025-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950611/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143717945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leaf dry mass per unit area and leaf pigments underlying the higher stomatal conductance of deciduous species relative to evergreen species in Dendrobium.","authors":"Feng-Ping Zhang, Xiao-Di Zhao, Li-Jun Han, Han-Run Li","doi":"10.1186/s40529-025-00457-z","DOIUrl":"10.1186/s40529-025-00457-z","url":null,"abstract":"<p><strong>Background: </strong>Leaf stomatal conductance is an important indicator of photosynthetic capacity. However, stomatal conductance is poorly quantified and rarely explored in the context of the leaf functional traits for epiphytes, particularly when it comes to herbaceous species with different leaf habits (deciduous vs. deciduous species). Here, we investigated leaf stomatal conductance, leaf dry mass per unit area, leaf thickness, stomatal density, abaxial epidermal cell size and pigment contents in 23 Dendrobium evergreen and deciduous species from a greenhouse. Our main objectives were to compare differences in all measured traits between evergreen and deciduous species, and to determine the relationships of leaf stomatal conductance with leaf functional traits and leaf pigments.</p><p><strong>Results: </strong>The results showed that the evergreen species of Dendrobium had thicker leaves and higher leaf dry mass per unit area, whereas deciduous species had higher leaf stomatal conductance and higher leaf chlorophyll contents. Leaf stomatal conductance had a negative correlation with leaf thickness, and dry mass per unit area, but a positive correlation with leaf pigment contents. There was a negative correlation between pigment contents and leaf dry mass per unit area.</p><p><strong>Conclusion: </strong>The results reveal the clear differences in leaf stomatal conductance, leaf functional traits and leaf pigments between deciduous and evergreen Dendrobium species, with the form groups showing trait values indicative of less investments in structural components and of more investments in photosynthetic carbon gain. Furthermore, leaf dry mass per unit area and leaf pigments play an important role in shaping leaf stomatal conductance.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"11"},"PeriodicalIF":3.4,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11930909/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143691029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biogeographic patterns and evolutionary history of Elatostema (Urticaceae).","authors":"Yu-Hsin Tseng, Alex K Monro, Jer-Ming Hu","doi":"10.1186/s40529-025-00456-0","DOIUrl":"10.1186/s40529-025-00456-0","url":null,"abstract":"<p><strong>Background: </strong>The paleotropics, home to half of Earth's rainforests, exhibit remarkable biodiversity and complex biogeographic patterns. Understanding the intercontinental distribution of plant taxa between Africa and Asia in this region is crucial for resolving longstanding debates on plant evolution and dispersal mechanisms. This study investigates the genus Elatostema, a widely distributed taxon found in subtropical and tropical Africa, Asia, and Australasia, aiming to elucidate the factors shaping its modern tropical disjunctions and evolutionary history.</p><p><strong>Result: </strong>Using molecular dating and ancestral area reconstruction, we reconstructed the historical biogeographic pattern of Elatostema. Our results indicated that the genus originated in tropical Asia during the Eocene, likely associated with boreotropical floras. The evolutionary history of Elatostema involved multiple intercontinental dispersal events, including two independent colonizations of Africa from Asia. Diversification within the core Elatostema clade was primarily driven by events in Asia and Oceania, with key factors contributing to this diversification including reciprocal dispersal between Malesia and Australasia, eastward island hopping and karstification in China. Furthermore, a geographical phylogenetic structure was observed within the core Elatostema clade, possibly due to limited seed and pollen dispersal.</p><p><strong>Conclusions: </strong>The present study provides the first comprehensive insights into the biogeography and evolution of Elatostema. The presence of numerous narrowly distributed endemics, relatively few widespread species, and geographical structures within Elatostema suggest that limited gene flow may be a crucial factor in speciation and evolutionary processes, similar to other species-rich genera.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"10"},"PeriodicalIF":3.4,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11923331/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143662593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of arbuscular mycorrhizal fungi in drought-resilient soybeans (Glycine max L.): unraveling the morphological, physio-biochemical traits, and expression of polyamine biosynthesis genes.","authors":"Elham R S Soliman, Reda E Abdelhameed, Rabab A Metwally","doi":"10.1186/s40529-025-00455-1","DOIUrl":"10.1186/s40529-025-00455-1","url":null,"abstract":"<p><strong>Background: </strong>Drought stress is a catastrophic abiotic stressor that impedes the worldwide output of commodities and the development of plants. The Utilizing biological antioxidant stimulators, Arbuscular mycorrhizal fungi (AMF) are one example increased the plants' ability to withstand the effects of drought. The symbiotic response of soybean (Glycine max L.) to AMF inoculation was assessed in the experiment presented herewith at different watering regimes (field capacity of 25, 50, and 90%). The vegetative, physio-biochemical traits, and regulation of genes involved in polyamine synthesis in G. max plants were evaluated.</p><p><strong>Results: </strong>The results obtained suggested that AMF inoculation has an advantage over plants that were non-inoculated in terms of their growth and all assessed criteria, which responded to drought stress by showing slower development. It is evident that the gas exchange parameters of the soybean plant were substantially reduced by 36.79 (photosynthetic rate; A), 60.59 (transpiration rate; E), and 53.50% (stomatal conductance gs), respectively, under severe stress of drought in comparison to control; non-stressed treatment. However, the AMF inoculation resulted in a 40.87, 29.89, and 33.65% increase in A, E, and gs levels, respectively, in extremely drought-stressful circumstances, when in contrast to non-AMF one that was grown under well-watered conditions. The drought level was inversely proportional to mycorrhizal colonization. The total antioxidant capacity, protein, and proline contents were all enhanced by AMF inoculation, while the malondialdehyde and hydrogen peroxide contents were decreased. Polyamine biosynthesis genes expression; Ornithine decarboxylase (ODC2), Spermidine synthase (SPDS) and Spermine synthase (SpS) were upregulated in drought and to even higher level in AMF's mild drought inoculated plants' shoots. This implies that AMF plays apart in the enhanced survival of soybean plants stressed by drought and reduced plant membranes damage by limiting the excessive production of oxidative stress generators; ROS.</p><p><strong>Conclusions: </strong>In summary, the present investigation demonstrates that inoculation of AMF may be a supportable and environmentally advantageous method for improving the physio-biochemical traits, plant growth, and polyamine biosynthesis genes of soybean plants in the incident of limited water availability.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"9"},"PeriodicalIF":3.4,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11914442/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143647123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chromosome number variation and phylogenetic divergence of East Asian Cirsium sect. Onotrophe subsect. Nipponocirsium (Compositae), with a new species from Taiwan.","authors":"Chih-Yi Chang, Pei-Chun Liao, Hsy-Yu Tzeng, Junko Kusumi, Zhi-Hui Su, Yen-Hsueh Tseng","doi":"10.1186/s40529-025-00454-2","DOIUrl":"10.1186/s40529-025-00454-2","url":null,"abstract":"<p><strong>Background: </strong>This study explored chromosome number variation, phylogenetic divergence, and mechanisms underlying speciation in East Asian thistle Cirsium Mill. sect. Onotrophe (Cass.) DC. subsect. Nipponocirsium Kitam. (Compositae). The study focused on the newly identified species from Taiwan: Cirsium pengii Y.H. Tseng, P.C. Liao & Chih Y. Chang. Utilizing phylotranscriptomic data to reconstruct evolutionary relationships between the Taiwanese and Japanese taxa of Cirsium subsect. Nipponocirsium as well as their divergence times and chromosomal characteristics. Additionally, the chromosome number, morphology, and pollen morphology of the unknown Cirsium taxon are compared with other known subsect. Nipponocirsium taxa from Taiwan.</p><p><strong>Results: </strong>Phylotranscriptomic analysis reveals a division within subsect. Nipponocirsium into Japanese and Taiwanese clades. In the Taiwanese clade, C. pengii is basal, while C. tatakaense remains monophyletic with other Taiwanese species despite higher genetic diversity. The prevalent chromosome number in this subsection is tetraploid (2n = 4x = 68), common in Japanese taxa, while Taiwanese members have 2n = 4x = 64. Notably, C. pengii has a diploid number (2n = 32), indicating descending dysploidy followed by polyploidization in Taiwan. This polyploidization, driven by glaciations, likely shaped the evolution of Nipponocirsium. Divergence time estimates suggest the separation of Japanese and Taiwanese clades around 0.74 million years ago (Myr) during glacial periods. Cirsium pengii diverged around 0.47 Myr, while tetraploid species C. kawakamii and C. tatakaense diverged around 0.35 Myr. These species likely evolved in separate refugia, with distinct species boundaries confirmed through species delimitation analysis, karyotype, morphology, and pollen morphology comparisons.</p><p><strong>Conclusions: </strong>These findings enhance our understanding of chromosomal evolution and speciation within subsect. Nipponocirsium and underscore the importance of integrating transcriptomic data in phylogenetic studies. This study provides a comprehensive framework for further investigations into the genetic diversity and adaptive mechanisms of this ecologically vital group.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"8"},"PeriodicalIF":3.4,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11828781/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143424952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A plant endophytic bacterium Burkholderia seminalis strain 869T2 increases plant growth under salt stress by affecting several phytohormone response pathways.","authors":"Hau-Hsuan Hwang, Yu-Ting Huang, Pei-Ru Chien, Fan-Chen Huang, Chih-Lin Wu, Liang-Yu Chen, Shih-Hsun Walter Hung, I-Chun Pan, Chieh-Chen Huang","doi":"10.1186/s40529-025-00453-3","DOIUrl":"10.1186/s40529-025-00453-3","url":null,"abstract":"<p><strong>Background: </strong>Due to global warming and gradual climate change, plants are subjected to a wide range of environmental stresses, adversely affecting plant growth and production worldwide. Plants have developed various mechanisms to overpower these abiotic stresses, including salt stress, drought, and high light intensity. Apart from their own defense strategies, plants can get help from the beneficial endophytic bacteria inside host plants and assist them in enduring severe growth conditions. A previously isolated plant endophytic bacteria, Burkholderia seminalis 869T2, from vetiver grass can produce auxin, synthesize siderophore, and solubilize phosphate. The B. seminalis 869T2 can colonize inside host plants and increase the growth of bananas, Arabidopsis, and several leafy vegetables.</p><p><strong>Results: </strong>We further demonstrated that different growth parameters of Arabidopsis and pak choi plants were significantly increased after inoculating the B. seminalis 869T2 under normal, salt, and drought stress conditions compared to the mock-inoculated plants. Both transcriptome analysis and quantitative real-time PCR results showed that expression levels of genes related to phytohormone signal transduction pathways, including auxin, gibberellin, cytokinin, and abscisic acid were altered in Arabidopsis plants after inoculated with the strain 869T2 under salt stress, in comparison to the mock-inoculated control with salt treatments. Furthermore, the accumulation levels of hydrogen peroxide (H₂O₂), electrolyte leakage (EL), and malondialdehyde (MDA) were lower in the 869T2-inoculated Arabidopsis and pak choi plants than in control plants under salt and drought stresses.</p><p><strong>Conclusions: </strong>The plant endophytic bacterium strain B. seminalis 869T2 may affect various phytohormone responses and reduce oxidative stress damage to increase salt and drought stress tolerances of host plants.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"7"},"PeriodicalIF":3.4,"publicationDate":"2025-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11794907/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143188382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing water status in rice plants in water-deficient environments using thermal imaging.","authors":"Chin-Ying Yang, Yan-Ci Zhang, Ya-Ling Hou","doi":"10.1186/s40529-025-00452-4","DOIUrl":"10.1186/s40529-025-00452-4","url":null,"abstract":"<p><strong>Background: </strong>Rice is a staple food for the global population. However, extreme weather events threaten the stability of the water supply for agriculture, posing a critical challenge to the stability of the food supply. The use of technology to assess the water status of rice plants enables the precise management of agricultural water resources.</p><p><strong>Results: </strong>The results of this study reveal that rice-producing regions with more severe drought have higher ion leakage rates, lower Soil Plant Analysis Development (SPAD) meter values, and reduced total chlorophyll content in plants. Although no significant differences were observed in red-green-blue (RGB) images, physiological parameters and canopy temperature differed significantly from conventional farming when infrared thermography was used to capture rice plants in the early stages of drought. The Crop Water Stress Index (CWSI), calculated from canopy temperature and atmospheric temperature, indicated a high correlation between access to water for rice plants and their physiological parameters. Regression analysis using CWSI and plant water status yielded a corrected coefficient of determination of 0.86.</p><p><strong>Conclusion: </strong>Our study demonstrate that infrared thermography can effectively detect early signs of water stress in rice, aiding farmers in irrigation planning and enabling precise management and optimal utilization of water resources.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"6"},"PeriodicalIF":3.4,"publicationDate":"2025-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11769923/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143036532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transcriptomic and enzymatic analysis of peroxidase families at the early growth stage of halophyte ice plant (Mesembryanthemum crystallinum L.) under salt stress.","authors":"Li-Ching Hsieh, Chia-Che Lee, Kai-Fu Zhang, Hui-Hsien Chang, Cheng-Hsun Li, Hsuan-Jung Huang, Hungchen Emilie Yen","doi":"10.1186/s40529-024-00450-y","DOIUrl":"10.1186/s40529-024-00450-y","url":null,"abstract":"<p><p>Ice plant (Mesembryanthemum crystallinum L.) is a halophyte and an inducible CAM plant. Ice plant seedlings display moderate salt tolerance, with root growth unaffected by 200 mM NaCl treatments, though hypocotyl elongation is hindered in salt-stressed etiolated seedlings. Superoxide anion accumulation was prominent in cotyledons and primary leaves but decreased in root tissues over time, with no significant effect from salt treatment. Hydrogen peroxide levels initially surged in both control and salt-treated seedlings, with higher and more persistent accumulation in the salt-treated seedlings. The activities of H₂O₂-scavenging ascorbate-glutathione cycle enzymes ascorbate peroxidase (APX), monodehydroascorbate reductase, and dehydroascorbate reductase increased, while guaiacol-dependent peroxidase activity decreased and catalase activity showed no change, indicating APX activity as the primary response to salt stress. Salt-induced APX activities were detected mainly in the microsomal fraction for light-grown seedlings and the cytosolic fraction for etiolated seedlings, highlighting plastids as the primary site of ROS accumulation under salt stress. An RNA-seq analysis of etiolated seedlings revealed about 8% unigenes showing more than a four-fold change in expression after a 6-h 200 mM NaCl treatment. GO enrichment analysis indicated that differentially expressed genes (DEGs) with increased transcript abundance were associated with ion transport, antioxidant activity, and stress responses, while DEGs with decreased transcript abundance were linked to metabolic and biosynthesis processes such as ribosomal protein synthesis and cell wall formation. This indicates that salt stress hinders growth but enhances ion homeostasis and stress response mechanisms. The expression of all eight APX genes were induced by a 48-hour salt treatment, with varying expression patterns. For class III peroxidase family, 14 out of 53 identified unigenes qualified as DEGs. The time-course expression patterns revealed that the transcript levels of McPrx4.1, McPrx12.1, and McPrx12.3 increased, while McPrx60.3 decreased. These findings highlight the distinct roles of class III peroxidases in balancing plant growth and stress responses, advancing our understanding of the mechanisms behind salt tolerance in halophytes. This study comprehensively analyzed changes in gene expression, antioxidant enzyme activity, and ROS accumulation in ice plant seedlings. Unveiling these responses will advance our understanding of the growth-stress balance in the intrinsic salt tolerance in halophytes.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"5"},"PeriodicalIF":3.4,"publicationDate":"2025-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11751343/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143000278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Xylaria iriomotensis sp. nov. from termite nests and notes on X. angulosa.","authors":"Izumi Okane, Huei-Mei Hsieh, Yu-Ming Ju, Chun-Ru Lin, Chun-Yun Huang, I-Ching Kuan","doi":"10.1186/s40529-024-00447-7","DOIUrl":"10.1186/s40529-024-00447-7","url":null,"abstract":"<p><strong>Background: </strong>Fungus gardens of the termite Odontotermes formosanus, excavated from Iriomote Island, Okinawa Prefecture, Japan, were subsequently incubated under laboratory conditions. A Xylaria species emerging from these fungus gardens was initially identified as X. angulosa, a species originally described from North Sulawesi, Indonesia. The Iriomote fungus is now described as a distinct species, X. iriomotensis.</p><p><strong>Results: </strong>Xylaria iriomotensis is peculiar in producing the teleomorph in culture but lacking an anamorph. Cultures of X. angulosa were obtained from two Taiwan specimens, which agree with the holotype from BO and the isotypes from NY and WSP in their stromata being repeatedly dichotomously branched and possessing a black core. In contrast to X. iriomotensis, X. angulosa does not form the teleomorph in culture but a typical Xylaria anamorph with conidiophores densely arranged in palisades. The ITS sequence obtained from the WSP isotype shared high similarities with those two Taiwan specimens as well as an Indian specimen, reconfirming the latter three specimens as X. angulosa. These four specimens shared 98.28-99.66% similarities at ITS sequences among themselves but only 84.25-85.01% similarities with X. iriomotensis. Molecular phylogenetic studies based on sequences of multiple protein-coding loci indicate that, while X. iriomotensis is grouped with three soil-dwelling species of the X. guepini cluster, X. angulosa belongs to the X. nigripes cluster, which includes all known species capable of producing massive sclerotia.</p><p><strong>Conclusion: </strong>Xylaria iriomotensis has the teleomorph known only in culture, remaining to be rediscovered in its natural habitat where the stromatal morphology may be somewhat varied. The geographic distribution of X. angulosa, previously known only in Indonesia, has been expanded to Taiwan and India. Xylaria angulosa grouping with the X. nigripes cluster in our phylogenetic analyses indicates its potential to form massive sclerotia within termite nests.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"4"},"PeriodicalIF":3.4,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11748714/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143000279","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activation of endogenous tolerance to bleaching stress by high salinity in cloned endosymbiotic dinoflagellates from corals.","authors":"Ching-Nen Nathan Chen, Tze Ching Yong, Jih-Terng Wang","doi":"10.1186/s40529-025-00451-5","DOIUrl":"10.1186/s40529-025-00451-5","url":null,"abstract":"<p><strong>Background: </strong>Large-scale coral bleaching events have become increasingly frequent in recent years. This process occurs when corals are exposed to high temperatures and intense light stress, leading to an overproduction of reactive oxygen species (ROS) by their endosymbiotic dinoflagellates. The ROS buildup prompts corals to expel these symbiotic microalgae, resulting in the corals' discoloration. Reducing ROS production and enhancing detoxification processes in these microalgae are crucial to prevent the collapse of coral reef ecosystems. However, research into the cell physiology and genetics of coral symbiotic dinoflagellates has been hindered by challenges associated with cloning these microalgae.</p><p><strong>Results: </strong>A procedure for cloning coral symbiotic dinoflagellates was developed in this study. Several species of coral symbionts were successfully cloned, with two of them further characterized. Experiments with the two species isolated from Turbinaria sp. showed that damage from light intensity at 340 μmol photons/m²/s was more severe than from high temperature at 36 °C. Additionally, preincubation in high salinity conditions activated their endogenous tolerance to bleaching stress. Pretreatment at 50 ppt salinity reduced the percentage of cells stained for ROS by 59% and 64% in the two species under bleaching stress compared to those incubated at 30 ppt. Furthermore, their Fv'/Fm' during the recovery period showed a significant improvement compared to the controls.</p><p><strong>Conclusions: </strong>These findings suggest that intense light plays a more important role than high temperatures in coral bleaching by enhancing ROS generation in the symbiotic dinoflagellates. The findings also suggest the genomes of coral symbiotic dinoflagellates have undergone evolutionary processes to develop mechanisms, regulated by gene expression, to mitigate damages caused by high temperature and high light stress. Understanding this gene expression regulation could contribute to strengthening corals' resilience against the impact of global climate change.</p>","PeriodicalId":9185,"journal":{"name":"Botanical Studies","volume":"66 1","pages":"3"},"PeriodicalIF":3.4,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11735819/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142982687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}