Annals of botany最新文献

{"title":"Elevational variation in trichomes of the alpine subnival woolly plant Eriophyton wallichii: Abiotic and biotic correlates and impacts on other traits.","authors":"Yue-Wen Xu, Shuang Cun, Zhi-Long Ma, Run He, Hang Sun, Bo Song","doi":"10.1093/aob/mcaf071","DOIUrl":"https://doi.org/10.1093/aob/mcaf071","url":null,"abstract":"<p><strong>Background and aims: </strong>Research has extensively examined how adaptations to extreme environments shape the highly specialized phenotypes of alpine subnival plants; however, large-scale biogeographic patterns of these specialized plant phenotypes remain largely unexplored.</p><p><strong>Methods: </strong>This study investigated the elevational patterns of leaf trichome density in the alpine subnival woolly plant Eriophyton wallichii, alongside its abiotic and biotic correlates, as well as the effect of trichome variation on chemical defence and chlorophyll content. We sampled 11 populations of E. wallichii spanning an elevation range of 4000-4800 m a.s.l., covering most of this species' altitudinal distribution and exhibiting significant variation in abiotic conditions, plant traits, and leaf herbivory.</p><p><strong>Key results: </strong>Our results revealed significant variation in leaf trichome density among populations, with a notable increase at higher elevations. This elevational trend was strongly negatively associated with the mean temperature during the growing season and, to a lesser extent, positively associated with leaf herbivory. In contrast, precipitation and solar radiation during the growing season showed minimal influence on trichome variation. Interestingly, phenolic compound concentrations in leaves decreased with increasing trichome density, whereas leaf chlorophyll content remained unchanged.</p><p><strong>Conclusions: </strong>Our results indicate that adaptation to low temperatures is a key driver in the evolution of woolly plant phenotypes in alpine subnival environments, highlighting potential consequences for these adaptations under global climate change and species distribution shifts. Additionally, the trade-off between trichome density and chemical defences may have significant implications for plant survival strategies in resource-limited environments. Our data also suggest that biotic interactions, especially those involving herbivores, may play an important role in shaping the adaptive mechanisms of some alpine subnival plants.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143967554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular polymorphisms of the nuclear and chloroplast genomes among African melon germplasms reveal abundant and unique genetic diversity, especially in Sudan.","authors":"Odirichi Nnennaya Imoh, Gentaro Shigita, Mitsuhiro Sugiyama, Tran Phuong Dung, Katsunori Tanaka, Mami Takahashi, Kazusa Nishimura, Yuki Monden, Hidetaka Nishida, Mashaer Goda, Michel Pitrat, Kenji Kato","doi":"10.1093/aob/mcaf028","DOIUrl":"https://doi.org/10.1093/aob/mcaf028","url":null,"abstract":"<p><strong>Background and aims: </strong>Africa is rich in wild species of Cucumis and is considered one of the origins of melon. However, our knowledge of African melon is limited, and genetic studies using melon germplasms with wide geographical coverage are required. Here, we analyzed the genetic structure of African melons, with emphasis on Sudan.</p><p><strong>Methods: </strong>Ninety-seven accessions of African melon were examined along with 77 reference accessions representing Asian melon and major horticultural groups. Molecular polymorphisms in the nuclear and chloroplast genomes were investigated using 12 RAPD, 7 SSR, and 3 SNP markers. Horticultural traits, including seed size, were measured for 46 accessions, mainly from Sudan.</p><p><strong>Key results: </strong>African melons were divided into large and small seed-types based on seed length: large seed-type from Northern Africa and small seed-type from Western and Southern Africa. Both seed types are common in Sudan. Molecular genetic diversity in these geographical populations was as high as in India, the Asian center of melon domestication. Large seed-type from Northern Africa were assigned to Pop4 by structure analysis and had Ib cytoplasm in common with Cantalupensis, Inodorus, and Flexuosus. Small seed-types were highly diversified and geographically differentiated; specifically, Pop1 with Ia cytoplasm in Southern Africa and South Asia, Pop2 with Ia in East Asia, including Conomon and Makuwa, and Pop3 with Ia or Ic in Africa. Sudanese small seed-types were grouped in Pop3, while their cytoplasm type was the mixture of Ia and Ic. Sudanese Tibish had Ic cytoplasm that was unique in Africa, common in Western Africa and Sudan, and also found in wild or feral types.</p><p><strong>Conclusions: </strong>Melon of Ic lineage, including Tibish, originated from wild melon in the \"western Sudan region,\" and independently of melon with Ia or Ib cytoplasm that originated in Asia. This clearly indicates the polyphyletic origin of melon.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143967555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulation of calcium, callose synthesis, membrane permeability and pectin methyl-esterase activity affect cell wall composition and embryo yield during Brassica napus microspore embryogenesis.","authors":"Antonio Calabuig-Serna, Daniel Sancho-Oviedo, Alba Rivas-Sendra, Estefanía Mata-Nicolás, Paloma Arjona-Mudarra, Ricardo Mir, Jose María Seguí-Simarro","doi":"10.1093/aob/mcaf054","DOIUrl":"https://doi.org/10.1093/aob/mcaf054","url":null,"abstract":"<p><strong>Background and aims: </strong>Microspore embryogenesis is a convenient inducible system to study the changes associated to the developmental reprogramming of cells. In this work, Brassica napus microspore cultures were used to study the role in the embryogenic switch of callose and pectin cell wall composition, which depends on Ca2+ levels.</p><p><strong>Methods: </strong>We used different chemicals to modulate Ca2+, callose and pectin methyl-esterification, including Ca(NO3)2, InsP3, 2-deoxy-D-glucose, benzyl alcohol, chitosan, epigallocatechin gallate and pectin methyl-esterase. Ca2+distribution, callose and cellulose were imaged with FluoForte, aniline blue and Pontamine Fast Scarlett stainings, respectively, and observed with confocal microscopy.</p><p><strong>Key results: </strong>Inhibition of callose synthesis with 2-deoxy-D-glucose evidenced that callose is essential for induction of microspore embryogenesis. A moderate increase of Ca2+ levels with Ca(NO3)2 or InsP3 promoted increased callose synthesis and deposition in the cell wall. However, the use of benzyl alcohol and chitosan to permeabilize the plasma membrane and allow for Ca2+ influx was not positive, as this prevented embryo development by inducing callus formation. Benzyl alcohol did not affect callose and cellulose deposition, but chitosan induced the formation of callose plugs, similar to those formed in response to pathogen attack. Inhibition of pectin methyl-esterase (PME) activity with epigallocatechin gallate during the first 3 days of culture produced ~70% more embryos, but prolonged exposures were negative. Instead, increased PME activity during the first three days was not positive, but when applied for 7 days, embryos increased ~60%.</p><p><strong>Conclusions: </strong>Together, these results confirm the relevant role of calcium and callose during the first stages of microspore induction, and suggest that the levels of pectin methyl-esterification in the cell wall are dynamic, and different cell wall compositions are required during the different stages of microspore embryogenesis.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143974461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotypic integration of post-germination traits in Quercus suber: morphology is mediated by acorn mass and leaf physiology by populations' climate.","authors":"Eduardo Vicente, Marion Carme, Filipe Costa E Silva, Boutheina Stiti, Natalia Vizcaíno-Palomar, Marta Benito Garzón","doi":"10.1093/aob/mcaf068","DOIUrl":"https://doi.org/10.1093/aob/mcaf068","url":null,"abstract":"<p><strong>Background and aims: </strong>Assessing intra-specific trait covariation across populations is essential to understand species' adaptive responses to climatic variation. However, in tree species, this is understudied for early-life stages despite they are more vulnerable to environmental changes and that climatic adaptations can differ between tree ages. In this paper, we studied the integrated phenotype of Quercus suber during the months following germination. For that, we assessed the covariation of key traits involved in seedlings' water and C economies along a gradient of aridity at seed origin.</p><p><strong>Methods: </strong>We performed a provenance trial with 157 Q. suber seedlings originating from 7 different populations across the species distribution. The seedlings were germinated and grown during 4 months under common conditions. Acorn mass along with 11 above- and below-ground traits involved in water and C use were measured. They were organized in latent variables and their covariation with increasing aridity and temperatures was analyzed using structural equation modelling (SEM). Individual traits were also analyzed with linear mixed-effects models to account for maternal effects.</p><p><strong>Key results: </strong>Seedlings from arid populations displayed higher leaf evaporative surface coupled with greater root development. They also depicted greater stomatal size and chlorophyll content, strongly linked to traits conferring drought and heat tolerance (low SLA and high flavonoids). The development of above- and below-ground tissues responded mainly to acorn mass, whereas leaf physiology variations were associated to populations' climate.</p><p><strong>Conclusions: </strong>Surprisingly, dry-origin seedlings display a more acquisitive strategy at the whole-plant level compared with seedlings from mesic provenances. This allows a greater water and carbon uptake capacities following germination, which is critical for their survival during their first summer. Leaf physiology adjustments to populations' climate contrasts with observations by other studies addressing juvenile trees, highlighting Q. suber varying adaptive strategies at different ontogenic stages.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143974497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An updated phylogeny of Boraginales based on the Angiosperms353 probe set: a roadmap for understanding morphological evolution.","authors":"Maria-Anna Vasile, Tim Böhnert, Julius Jeiter, Domingos Cardoso, Peter W Moonlight, Maximilian Weigend","doi":"10.1093/aob/mcaf061","DOIUrl":"https://doi.org/10.1093/aob/mcaf061","url":null,"abstract":"<p><strong>Background and aims: </strong>Boraginales, a subcosmopolitan order with ~2,700 species in currently 11 families, has seen fluctuating classification at the family and generic levels. Gynoecium and fruit morphology have been pivotal in morphological classifications, but a systematic evaluation based on anatomical and ontogenetic data has not been attempted.</p><p><strong>Methods: </strong>We revisited the phylogenetic relationships in Boraginales by analysing 162 newly sequenced samples using the Angiosperms353 probe set, together with existing data from 88 samples. Our sampling covers >80% of the genera and all currently and previously recognized families. A morphological assessment of taxonomically important gynoecial and fruit characters was done to guide our proposed family-level classification.</p><p><strong>Key results: </strong>The phylogenies are largely consistent with previous phylogenetic studies, with better resolution overall and support from both data sets (exons, supercontigs) and all analyses implemented (coalescence, ASTRAL-Pro3, concatenation). The placement of Hydrophyllaceae as nested within Namaceae is a novel result, while the placement of the parasitic Lennoaceae as nested within Ehretiaceae is confirmed with maximum confidence. The placement of Codonaceae remains ambiguous: retrieved within the Boraginales I, as sister to the clade comprising Wellstediaceae and Boraginaceae based on exons, and as sister branch to all remaining Boraginales II based on supercontigs. We propose the recognition of a total of nine families in Boraginales. Tribal relationships in Boraginaceae subfam. Cynoglossoideae are fully resolved for the first time. Our data show that shifts in placentation and ovule number are instrumental for the arisal of complex internal ovary architectures.</p><p><strong>Conclusions: </strong>The results highlight the effectiveness of the Angiosperms353 probe set for understanding the evolutionary history of Boraginales and pave the way for resolving remaining unresolved nodes and taxonomic issues. Complex modifications of bicarpellate ovaries led to an extreme and lineage-specific diversification of fruits that likely played a crucial role in Boraginales macroevolution. Combining this highly resolved phylogeny with future critical morphological analyses promises a deep understanding of evolutionary trajectories in Boraginales.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143973594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Roots go through rapid hydraulic recovery following moderate water stress.","authors":"Feng-Ping Li, Jairo A Palta, Guang-Qian Yao, Yuan-Yuan Zeng, Min-Hui Bi, Xue-Qian Tian, Shi-Hua Qi, Lin Cai, Xiang-Wen Fang","doi":"10.1093/aob/mcaf060","DOIUrl":"https://doi.org/10.1093/aob/mcaf060","url":null,"abstract":"<p><strong>Background and aims: </strong>Plant dehydration and rehydration cycles are universal phenomena in natural environments, especially in arid environments. Once a moderate water stress is relieved, the plant hydraulic system can recover, but the recovery process across roots, stems and leaves remains unknown. We examined the recovery dynamics of plant hydraulics and photosynthetic activity following moderate water stress in one herbaceous plant (Glycine max) and one woody shrub (Caragana korshinskii).</p><p><strong>Methods: </strong>The research was conducted on pot-grown plants in a glasshouse and the recovery dynamics of the predawn leaf water potential (ψleaf), hydraulic conductance of the leaf (Kleaf), of stem (Kstem) and of root (Kroot), stomatal conductance (gs), leaf photosynthetic rate (An) and nonstructural carbohydrates (NSC) were monitored after the plants were released from a moderate water stress.</p><p><strong>Key results: </strong>Under moderate water stress with decreasing predawn ψleaf, Kleaf and Kroot in both species were more sensitive to water deficit than was Kstem, and the decrease in gs was faster than that in An, resulting in an increase in water use efficiency (WUEi); NSC decreased in leaves and stems but accumulated in roots. After rehydration, both species showed a faster recovery in Kroot and Kstem than in Kleaf, and a slower recovery in gs than in An, resulting in an increase in WUEi.</p><p><strong>Conclusions: </strong>The rapid recovery in Kroot contributes to plant recovery from water stress, and slow recovery in Kleaf limits stomatal reopening, thus reducing transpiration and maintaining high WUEi. These traits enable species to tolerate drought.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143810173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Longevity, Cryopreservation, and Propagation of Carnivorous Plants Seeds: Insights From 13 Species in Long-Term Ex situ Collections.","authors":"Daniel Ballesteros, Rachael M Davies, Jennifer L Peach, Valerie C Pence","doi":"10.1093/aob/mcaf058","DOIUrl":"https://doi.org/10.1093/aob/mcaf058","url":null,"abstract":"<p><strong>Background and aims: </strong>A quarter of the assessed carnivorous plants (CPs) are threatened with extinction, and the effectiveness of ex situ conservation initiatives must be evaluated to complement in situ conservation efforts. Conventional seed storage (e.g., 15% relative humidity, -20°C) is the most common and efficient strategy for plant ex situ conservation, but seeds of diverse CPs might be short-lived at these conditions. Thus, there is a need to empirically and comparatively assess their longevity and evaluate the success of alternative storage options.</p><p><strong>Methods: </strong>Diverse seed collections were used to assess longevity of seeds of thirteen CP species stored (some up to 30 years) at various storage conditions: ambient/uncontrolled, conventional, and cryogenic.</p><p><strong>Key results: </strong>The relative short longevity of CP seeds stored in ambient/uncontrolled and conventional conditions was confirmed for some taxa (e.g., Drosera rotundifolia L.). Nevertheless, despite this potential short longevity, seeds of 64% of accessions tested retained their initial viability for up to two decades when stored at conventional seed bank conditions. Only some accessions stored for longer times (> 25 years), showed significant signs of deterioration, with D. rotundifolia and D. anglica Huds. showing P50 values in the region of other taxa considered medium/short or short-lived at comparable cold/dry storage conditions. As an alternative (or complement) to conventional seed banking, cryogenic storage of dry seeds was able to preserve a high germination percentage of seeds of CPs stored up to two decades. Furthermore, seedlings obtained developed normally into healthy plants when monitored up to 1.5 years after germination.</p><p><strong>Conclusions: </strong>Despite the potential short lifespan of seeds of some CP taxa, this paper highlights and supports their routine dry storage in ex situ conservation programs to support in situ conservation initiatives.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143771103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using pedigree tracking of the ex situ metacollection of Amorphophallus titanum (Araceae) to identify challenges to maintaining genetic diversity in the botanical community.","authors":"O G Murrell, Z Diaz-Martin, K Havens, M Hughes, A Meyer, J Tutt, N Zerega, J B Fant","doi":"10.1093/aob/mcaf038","DOIUrl":"https://doi.org/10.1093/aob/mcaf038","url":null,"abstract":"<p><strong>Background and aims: </strong>Rapid global biodiversity loss emphasizes the need to employ strategies that conserve the long-term viability of ex situ plant collections. A pedigree-based management approach is an effective strategy to track genetic diversity of living collections; however, its implementation requires accession-level data for all individuals across all botanic garden collections. Here, we use historic accession records to construct a pedigree and test how effective current protocols have been in managing ex situ diversity.</p><p><strong>Methods: </strong>We selected the titan arum, Amorphophallus titanum (Araceae), for this study, as it is exceptional, endangered, and has been globally held in collections for nearly 150 years. A pedigree-based data management approach would benefit the ex situ conservation of many similar species. Using accession data from nearly 1200 individual plants from 111 institutions worldwide, we constructed a pedigree to track the history of this species in collections and evaluate how well genetic diversity has been maintained in the metacollection.</p><p><strong>Key results: </strong>We found that data and records for the ex situ metacollection of Amorphophallus titanum are severely lacking and are not standardized within the botanical community. Using the available data, we found that the metacollection is derived from few founders, material is rarely exchanged between institutions on different continents, and nearly a quarter of known crosses are between related individuals.</p><p><strong>Conclusions: </strong>Our work highlights the need for consistent, detailed record-keeping for effective implementation of an informed pedigree-based management approach and long-term maintenance of collections of endangered plant species in botanic gardens.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143771106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of climate extremes and grazing on functional traits of a grassland community: insights from a 20-year experiment.","authors":"Nicola Pavanetto, Enrico Tordoni, Francesco Petruzzellis, Simona Maccherini, Andrea Nardini, Eleonora Beccari, Carlo Ricotta, Duccio Rocchini, Luisa Conti, Emanuele Fanfarillo, Miris Castello, Giovanni Bacaro","doi":"10.1093/aob/mcaf059","DOIUrl":"https://doi.org/10.1093/aob/mcaf059","url":null,"abstract":"<p><strong>Background and aims: </strong>Climate change, particularly the increased frequency of extreme climatic events, poses significant challenges to the biodiversity and functionality of semi-natural grasslands. However, the response of plant functional traits of grassland communities to climate extremes is still an unresolved issue. Using data from a long-term experiment, we aimed to characterize the functional response of a grassland community to simultaneous long-term effects of grazing and climate extremes.</p><p><strong>Methods: </strong>For over a 20-year period, we monitored the species composition of grazed and ungrazed grassland plots. We measured functional traits defining the Leaf Economics Spectrum (LES) and the Hydraulic Safety-Efficiency (HSE) trade-offs, and we identified the temporal dynamics of single traits at the community level as well as the changes in functional strategies among grazed and ungrazed communities. Then, we assessed the role of climatic extremes in driving the changes in functional composition.</p><p><strong>Key results: </strong>Grazed plots, in the first few years, were dominated by fast-growing species with more acquisitive strategies compared to ungrazed plots. However, both communities showed a reorganization in the functional structure over time, pointing towards a selection of trait combinations favoring more conservative, stress-tolerant strategies. The joint effect of grazing and climate extremes significantly altered the functional composition of the grazed community, leading to a shift from species with grazing-tolerant traits to species with grazing-avoidant, and drought-tolerant, traits.</p><p><strong>Conclusions: </strong>We found that grazing pressure generally promoted functional diversity but led to rapid shifts in community composition when combined with prolonged drought events. In contrast, the ungrazed community, dominated by species with conservative resource-use strategies, showed more stable functional richness and divergence, as well as a reduced sensitivity to climatic extremes. These results underscore the importance of carefully evaluating grazing in the context of climate change, particularly to guide restoration and conservation efforts.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143771102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Geosiphon-Nostoc symbiosis: recent elaboration, or remnant of an enduring association?","authors":"Matthew P Nelsen, H T Lumbsch, C Kevin Boyce","doi":"10.1093/aob/mcaf057","DOIUrl":"https://doi.org/10.1093/aob/mcaf057","url":null,"abstract":"<p><strong>Background and aims: </strong>Fungal associations with photosynthetic microbes have regularly been invoked as precursors to the evolution of land plants and their mycorrhizal associations. The fungus Geosiphon pyriformis (Glomeromycotina) deviates from its arbuscular mycorrhizal (AM)-forming relatives through the presence of an intracellular symbiosis with Nostoc cyanobacteria, and is frequently viewed as the only extant representative of an ancient and formerly widespread association between fungi and cyanobacteria that occupied early terrestrial ecosystems. Here we add to growing evidence suggesting the Geosiphon-Nostoc-like associations are not ancestral to AM associations and did not occupy landscapes prior to the evolution of land plants. In addition, we discuss the underlying drivers contributing to the origination and persistence of this argument and discuss other ways in which Geosiphon has been misunderstood.</p><p><strong>Methods: </strong>We inferred timescaled phylogenies of Glomeromycotina and utilized ancestral state reconstruction to both evaluate the plausibility of a Geosiphon-like ancestral state, and highlight the additional complexity required to maintain support for a Geosiphon-like ancestral state.</p><p><strong>Key results: </strong>Our analyses overwhelmingly recovered the Geosiphon-like state as being derived from AM associations.</p><p><strong>Conclusions: </strong>Our work illustrates the diverse ways in which Geosiphon has been misunderstood and adds to a growing body of evidence suggesting the Geosiphon-like ecology is derived from AM-forming ancestors and did not occupy terrestrial ecosystems prior to the evolution of land plants. We conclude by discussing outstanding questions pertaining to the ecology and evolution of Glomeromycotina fungi.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143741814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}