Carlos A Ordóñez-Parra, Natália F Medeiros, Roberta L C Dayrell, Soizig Le Stradic, Daniel Negreiros, Tatiana Cornelissen, Fernando A O Silveira
Background and aims: Rock outcrop vegetation is distributed worldwide and hosts a diverse and unique flora that evolved under harsh environmental conditions. Unfortunately, seed ecology in such ecosystems has received little attention, especially regarding seed traits, germination responses to abiotic factors and the potential role of phylogenetic relatedness on such features Here, we provide the first quantitative and phylogenetically-informed synthesis of the seed functional ecology of Brazilian rock outcrop vegetation, with a particular focus on quartzitic and ironstone campo rupestre.
Methods: Using a database of functional trait data, we calculated the phylogenetic signal of seven seed traits for 371 taxa and tested whether they varied among growth forms, geographic distribution, and microhabitats. We also conducted meta-analyses that included 4,252 germination records for 102 taxa to assess the effects of light, temperature, and fire-related cues on the germination of campo rupestre species and explored how the aforementioned ecological groups and seed traits modulate germination responses.
Key results: All traits and germination responses showed a moderate-to-strong phylogenetic signal. Campo rupestre species responded positively to light and had maximum germination between 20-25 ºC. The effect of temperatures beyond this range was moderated by growth form, species geographic distribution, and microhabitat. Seeds exposed to heat shocks above 80 °C lost viability, but smoke accelerated germination. We found a moderating effect of seed mass for in responses to light and heat shocks, with larger, dormant seeds tolerating heat better but less sensitive to light. Species from xeric habitats evolved phenological strategies to synchronise germination during periods of increased soil water availability.
Conclusions: Phylogenetic relatedness plays a major role in shaping seed ecology of Brazilian rock outcrop vegetation. Nevertheless, seed traits and germination responses varied significantly between growth forms, species geographic distribution and microhabitats, providing support to the regeneration niche hypothesis and the role of functional traits in shaping germination in these ecosystems.
背景和目的:岩石露头植被分布于世界各地,拥有在严酷环境条件下进化出的多样而独特的植物区系。遗憾的是,这类生态系统中的种子生态学很少受到关注,尤其是在种子性状、萌发对非生物性因素的反应以及系统发育相关性对这些特征的潜在作用等方面。在此,我们首次对巴西岩石露头植被的种子功能生态学进行了定量和系统发育信息综合分析,并特别关注石英岩和铁岩露头植被:方法:我们利用功能性状数据数据库,计算了 371 个类群的七种种子性状的系统发育信号,并测试了这些性状在生长形式、地理分布和微生境之间是否存在差异。我们还对102个类群的4252条萌发记录进行了荟萃分析,以评估光照、温度和与火有关的线索对莰烯物种萌发的影响,并探讨上述生态类群和种子性状如何调节萌发反应:主要结果:所有性状和萌发反应都显示出中等至强烈的系统发育信号。Campo rupestre物种对光照有积极反应,在20-25 ºC之间萌发率最高。温度超过这一范围时,生长形式、物种地理分布和微生境对其影响有所缓和。种子暴露在 80 °C 以上的热冲击下会失去活力,但烟雾会加速发芽。我们发现种子质量对光和热冲击的反应有调节作用,较大的休眠种子对热的耐受性较好,但对光的敏感性较低。干旱栖息地的物种进化出了物候学策略,以便在土壤水分供应增加的时期同步萌发:结论:系统发育的亲缘关系在巴西岩石露头植被种子生态学的形成过程中发挥了重要作用。然而,不同生长形式、物种地理分布和微生境之间的种子特征和萌发反应差异很大,这为再生生态位假说和功能特征在这些生态系统中影响萌发的作用提供了支持。
{"title":"Seed functional ecology in Brazilian rock outcrop vegetation: an integrative synthesis.","authors":"Carlos A Ordóñez-Parra, Natália F Medeiros, Roberta L C Dayrell, Soizig Le Stradic, Daniel Negreiros, Tatiana Cornelissen, Fernando A O Silveira","doi":"10.1093/aob/mcae160","DOIUrl":"https://doi.org/10.1093/aob/mcae160","url":null,"abstract":"<p><strong>Background and aims: </strong>Rock outcrop vegetation is distributed worldwide and hosts a diverse and unique flora that evolved under harsh environmental conditions. Unfortunately, seed ecology in such ecosystems has received little attention, especially regarding seed traits, germination responses to abiotic factors and the potential role of phylogenetic relatedness on such features Here, we provide the first quantitative and phylogenetically-informed synthesis of the seed functional ecology of Brazilian rock outcrop vegetation, with a particular focus on quartzitic and ironstone campo rupestre.</p><p><strong>Methods: </strong>Using a database of functional trait data, we calculated the phylogenetic signal of seven seed traits for 371 taxa and tested whether they varied among growth forms, geographic distribution, and microhabitats. We also conducted meta-analyses that included 4,252 germination records for 102 taxa to assess the effects of light, temperature, and fire-related cues on the germination of campo rupestre species and explored how the aforementioned ecological groups and seed traits modulate germination responses.</p><p><strong>Key results: </strong>All traits and germination responses showed a moderate-to-strong phylogenetic signal. Campo rupestre species responded positively to light and had maximum germination between 20-25 ºC. The effect of temperatures beyond this range was moderated by growth form, species geographic distribution, and microhabitat. Seeds exposed to heat shocks above 80 °C lost viability, but smoke accelerated germination. We found a moderating effect of seed mass for in responses to light and heat shocks, with larger, dormant seeds tolerating heat better but less sensitive to light. Species from xeric habitats evolved phenological strategies to synchronise germination during periods of increased soil water availability.</p><p><strong>Conclusions: </strong>Phylogenetic relatedness plays a major role in shaping seed ecology of Brazilian rock outcrop vegetation. Nevertheless, seed traits and germination responses varied significantly between growth forms, species geographic distribution and microhabitats, providing support to the regeneration niche hypothesis and the role of functional traits in shaping germination in these ecosystems.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142153016","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}
Background and aims: A hierarchical micro-topography of ridges and steps renders the trap rim of carnivorous Nepenthes pitcher plants unusually wettable, and slippery for insects when wet. This complex three-dimensional epidermis structure forms, hidden from plain sight, inside the still-closed developing pitcher bud. Here, we reveal the sequence of epidermal patterning events that shape the trap rim. By linking this sequence to externally visible markers of bud development, we provide a framework for targeting individual stages of surface development in future studies.
Methods: We used cryo-scanning electron microscopy to investigate the detailed morphogenesis and epidermal patterning of the Nepenthes x hookeriana pitcher rim. In addition, we collected morphometric and qualitative data from developing pitcher traps including those sampled for microscopy.
Key results: We identified three consecutive patterning events. First, strictly oriented cell divisions resulted in radially aligned rows of cells and established a macroscopic ridge-and-groove pattern. Next, conical papillate cells formed, and papillae elongated towards the trap interior, increasingly overlapping adjacent cells and eventually forming continuous microscopic ridges. In between these ridges, the flattened papillae formed acutely angled arched steps. Finally, the cells elongated radially, thereby establishing the convex collar shape of the rim. This general sequence of surface development also showed a spatial progression from the outer to the inner trap rim edge, with several consecutive developmental stages co-occurring at any given time.
Conclusions: We demonstrate that the complex surface microtopography of the Nepenthes pitcher rim develops by sequentially combining widespread, evolutionarily conserved epidermal patterning processes in a new way. This makes the Nepenthes trap rim an excellent model for studying epidermal patterning mechanisms in leaves.
背景和目的:由脊和阶梯组成的分层微地形使食肉莲属投手植物的诱捕器边缘异常湿润,潮湿时对昆虫来说很滑。这种复杂的三维表皮结构隐藏在仍处于闭合状态的发育中的投手芽内。在这里,我们揭示了形成陷阱边缘的表皮模式化事件序列。通过将这一序列与芽发育的外部可见标记联系起来,我们提供了一个框架,以便在未来的研究中瞄准表面发育的各个阶段:方法:我们利用低温扫描电子显微镜研究了尼泊尔麝香草(Nepenthes x hookeriana)捕虫圈的详细形态发生和表皮图案。此外,我们还收集了发育中的蝮蛇诱捕器(包括显微镜取样的诱捕器)的形态计量和定性数据:我们发现了三个连续的模式化事件。首先,严格定向的细胞分裂产生了径向排列的细胞行,并形成了宏观的脊沟图案。接着,锥形乳头状细胞形成,乳头向捕获器内部伸长,越来越多地与相邻细胞重叠,最终形成连续的微观脊。在这些脊之间,扁平的乳头形成尖角弧形台阶。最后,细胞径向拉长,从而形成凸领状的边缘。这种表面发育的一般顺序还显示出从外侧到内侧陷阱边缘的空间进展,在任何给定时间内都会同时出现几个连续的发育阶段:结论:我们的研究表明,尼泊金吸虫诱捕器边缘复杂的表面微形貌是通过以一种新的方式将广泛存在且在进化过程中得到保护的表皮模式化过程按顺序结合起来而形成的。这使得景天科捕虫栅成为研究叶片表皮图案机制的绝佳模型。
{"title":"Carnivorous Nepenthes pitcher plants combine common developmental processes to make a complex epidermal trapping surface.","authors":"Oona C Lessware, Judith M Mantell, Ulrike Bauer","doi":"10.1093/aob/mcae147","DOIUrl":"https://doi.org/10.1093/aob/mcae147","url":null,"abstract":"<p><strong>Background and aims: </strong>A hierarchical micro-topography of ridges and steps renders the trap rim of carnivorous Nepenthes pitcher plants unusually wettable, and slippery for insects when wet. This complex three-dimensional epidermis structure forms, hidden from plain sight, inside the still-closed developing pitcher bud. Here, we reveal the sequence of epidermal patterning events that shape the trap rim. By linking this sequence to externally visible markers of bud development, we provide a framework for targeting individual stages of surface development in future studies.</p><p><strong>Methods: </strong>We used cryo-scanning electron microscopy to investigate the detailed morphogenesis and epidermal patterning of the Nepenthes x hookeriana pitcher rim. In addition, we collected morphometric and qualitative data from developing pitcher traps including those sampled for microscopy.</p><p><strong>Key results: </strong>We identified three consecutive patterning events. First, strictly oriented cell divisions resulted in radially aligned rows of cells and established a macroscopic ridge-and-groove pattern. Next, conical papillate cells formed, and papillae elongated towards the trap interior, increasingly overlapping adjacent cells and eventually forming continuous microscopic ridges. In between these ridges, the flattened papillae formed acutely angled arched steps. Finally, the cells elongated radially, thereby establishing the convex collar shape of the rim. This general sequence of surface development also showed a spatial progression from the outer to the inner trap rim edge, with several consecutive developmental stages co-occurring at any given time.</p><p><strong>Conclusions: </strong>We demonstrate that the complex surface microtopography of the Nepenthes pitcher rim develops by sequentially combining widespread, evolutionarily conserved epidermal patterning processes in a new way. This makes the Nepenthes trap rim an excellent model for studying epidermal patterning mechanisms in leaves.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142139069","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}
Background and aims: Absorptive root traits play important roles in acquisition of water and nutrients from soil by plants. Despite numerous reports on the changes in species dominance under long-term drought in grassland community, few studies have specifically investigated absorptive root traits of these dominant species in grasslands, especially in the alpine grasslands.
Methods: Here, two grass species (Leymus secalinus and Stipa purpurea) differing in their responses to drought were selected from an alpine steppe. A series of absorptive root traits were examined under drought in a 3-year glasshouse experiment.
Key results: We found that drought had no effects on root morphological and architectural traits, whereas root physiological traits and rooting depth differed in their responses to drought. Specifically, drought significantly reduced root respiration and enhanced organ carbon (C) exudation rate, carboxylate exudation rate, acid phosphatase activity and rooting depth of L. secalinus. Particularly, L. secalinus released more citrate into the rhizosphere under drought than S. purpurea. In contrast, these root traits of S. purpurea remained relatively unchanged in response to the drought. These differential responses would render L. secalinus more competitive in acquisition of nutrients and water, thus contributing to its dominance in the community under drought. Moreover, root respiration was negatively correlated with organic C exudation rate, carboxylate exudation rate and acid phosphatase activity, indicating a tradeoff between root respiration and root exudates to acquire nutrients and water by optimizing C allocation under drought. Additionally, all root traits exhibited two independent dimensions in root economic space (RES) for both species under drought.
Conclusions: These results indicate that the plant species with great capacity to acquire water and nutrients in soil by optimizing C allocation under drought will be dominant in the community of the alpine grasslands. These findings provide an important insight into species re-ordering under drought on the Tibetan Plateau.
{"title":"Two grasses differ in their absorptive root physiological traits and rooting depth under drought in an alpine steppe.","authors":"Zhi Zheng, Yurui Zhang, Ziyue Li, Feifei Dong, Lijuan Chen","doi":"10.1093/aob/mcae151","DOIUrl":"https://doi.org/10.1093/aob/mcae151","url":null,"abstract":"<p><strong>Background and aims: </strong>Absorptive root traits play important roles in acquisition of water and nutrients from soil by plants. Despite numerous reports on the changes in species dominance under long-term drought in grassland community, few studies have specifically investigated absorptive root traits of these dominant species in grasslands, especially in the alpine grasslands.</p><p><strong>Methods: </strong>Here, two grass species (Leymus secalinus and Stipa purpurea) differing in their responses to drought were selected from an alpine steppe. A series of absorptive root traits were examined under drought in a 3-year glasshouse experiment.</p><p><strong>Key results: </strong>We found that drought had no effects on root morphological and architectural traits, whereas root physiological traits and rooting depth differed in their responses to drought. Specifically, drought significantly reduced root respiration and enhanced organ carbon (C) exudation rate, carboxylate exudation rate, acid phosphatase activity and rooting depth of L. secalinus. Particularly, L. secalinus released more citrate into the rhizosphere under drought than S. purpurea. In contrast, these root traits of S. purpurea remained relatively unchanged in response to the drought. These differential responses would render L. secalinus more competitive in acquisition of nutrients and water, thus contributing to its dominance in the community under drought. Moreover, root respiration was negatively correlated with organic C exudation rate, carboxylate exudation rate and acid phosphatase activity, indicating a tradeoff between root respiration and root exudates to acquire nutrients and water by optimizing C allocation under drought. Additionally, all root traits exhibited two independent dimensions in root economic space (RES) for both species under drought.</p><p><strong>Conclusions: </strong>These results indicate that the plant species with great capacity to acquire water and nutrients in soil by optimizing C allocation under drought will be dominant in the community of the alpine grasslands. These findings provide an important insight into species re-ordering under drought on the Tibetan Plateau.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142124608","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}
Zhixia Sun, Lihua Yang, Hanghui Kong, Ming Kang, Jing Wang
Background and aims: Subtropical China is dominated by evergreen broad-leaved forests (EBLFs) and is acknowledged as a critical region for its high floristic richness and endemism. Understanding of evolutionary mechanisms of such global biodiversity hotspots comes almost exclusively from long-lived tree species. Herbaceous plants represent critical biodiversity components in forests, however, the diversification history of understory herbs in subtropical EBLFs remain poorly understood. Here, we investigated the phylogeographic patterns and demographic history of Oreocharis auricula, a widespread perennial herb endemic to the EBLFs of subtropical China.
Methods: Both cpDNA sequences and single-copy nuclear genes were used to investigate the genetic variation among 657 individuals from 68 populations. Evidences from molecular dating, demographic history construction, and species distribution modeling were also combined to infer the phylogeography and evolutionary history of O. auricula.
Key results: Strong phylogeographic signals have been congruently observed using nuclear and plastid DNA markers, with the diversification patterns generally consistent with the recognized floristic subdivisions of subtropical China. Notably, we revealed an important phylogeographic barrier along the Nanling mountain range, which is also around a climatic transition at 24-26°N latitude in subtropical China, separating the south monsoon subtropical EBLFs from the mid-subtropical EBLFs. Demographic expansion and significant niche divergence were detected among the extant lineages, which may have diverged during the early Pleistocene.
Conclusions: The inherent characteristics of understory herbs with limited dispersal and short generation time intensify the genetic divergence response of O. auricula to abiotic forces, contributing to the profound phylogeographic imprints of mountains and climate in such herbaceous flora. To further substantiate the generality of the identified patterns, it is paramount to extend phylogeographic investigations to other understory herbaceous taxa in subtropical China. These results have expanded our understanding of the diversification processes of subtropical forests in China.
{"title":"Phylogeographic patterns match the floristic subdivisions: The diversification history of a widespread herb in subtropical China.","authors":"Zhixia Sun, Lihua Yang, Hanghui Kong, Ming Kang, Jing Wang","doi":"10.1093/aob/mcae157","DOIUrl":"https://doi.org/10.1093/aob/mcae157","url":null,"abstract":"<p><strong>Background and aims: </strong>Subtropical China is dominated by evergreen broad-leaved forests (EBLFs) and is acknowledged as a critical region for its high floristic richness and endemism. Understanding of evolutionary mechanisms of such global biodiversity hotspots comes almost exclusively from long-lived tree species. Herbaceous plants represent critical biodiversity components in forests, however, the diversification history of understory herbs in subtropical EBLFs remain poorly understood. Here, we investigated the phylogeographic patterns and demographic history of Oreocharis auricula, a widespread perennial herb endemic to the EBLFs of subtropical China.</p><p><strong>Methods: </strong>Both cpDNA sequences and single-copy nuclear genes were used to investigate the genetic variation among 657 individuals from 68 populations. Evidences from molecular dating, demographic history construction, and species distribution modeling were also combined to infer the phylogeography and evolutionary history of O. auricula.</p><p><strong>Key results: </strong>Strong phylogeographic signals have been congruently observed using nuclear and plastid DNA markers, with the diversification patterns generally consistent with the recognized floristic subdivisions of subtropical China. Notably, we revealed an important phylogeographic barrier along the Nanling mountain range, which is also around a climatic transition at 24-26°N latitude in subtropical China, separating the south monsoon subtropical EBLFs from the mid-subtropical EBLFs. Demographic expansion and significant niche divergence were detected among the extant lineages, which may have diverged during the early Pleistocene.</p><p><strong>Conclusions: </strong>The inherent characteristics of understory herbs with limited dispersal and short generation time intensify the genetic divergence response of O. auricula to abiotic forces, contributing to the profound phylogeographic imprints of mountains and climate in such herbaceous flora. To further substantiate the generality of the identified patterns, it is paramount to extend phylogeographic investigations to other understory herbaceous taxa in subtropical China. These results have expanded our understanding of the diversification processes of subtropical forests in China.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142124607","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}
Hanna Makowski, Emily Scott, Keric Lamb, Laura F Galloway
Background and aims: Secondary pollen-presentation, the relocation of pollen from the anthers to elsewhere on the flower, has evolved multiple times across many plant families. While hypotheses suggest it evolved to promote outcrossing, a byproduct of relocation may be protection of pollen from loss due to abiotic factors. In Campanulaceae pollen is presented on pollen-collecting hairs along the style and the hairs retract over time and release pollen for transfer. Campanulaceae taxa vary in the degree to which pollen is exposed to environmental factors due to variation in the corolla shape and size. We tested the protective function of pollen-collecting hairs by assessing whether there was a tradeoff between the protection provided by the corolla and the pollen-collecting hairs.
Methods: We used phylogenetic comparative methods to test for associations between pollen-collecting hair length, floral shape and size metrics, and pollen exposure traits across 39 species.
Results: We anticipated longer pollen-collecting hairs in taxa with more exposed pollen presentation but found there was no relationship between estimates of pollen exposure and pollen-collecting hair length. However, pollen-collecting hair length scaled allometrically with floral size, and variation in pollen-collecting hairs, as well as most floral traits, was phylogenetically structured.
Conclusions: These results indicate that variation in pollen exposure across species does not structure variation in the pollen-collecting hairs, rather hair length scales allometrically and is phylogenetically constrained, therefore pollen-collecting hairs are unlikely to facilitate protection from environmental pressures.
{"title":"Compensating for the corolla? Pollen exposure is not associated with pollen collecting hair length.","authors":"Hanna Makowski, Emily Scott, Keric Lamb, Laura F Galloway","doi":"10.1093/aob/mcae139","DOIUrl":"https://doi.org/10.1093/aob/mcae139","url":null,"abstract":"<p><strong>Background and aims: </strong>Secondary pollen-presentation, the relocation of pollen from the anthers to elsewhere on the flower, has evolved multiple times across many plant families. While hypotheses suggest it evolved to promote outcrossing, a byproduct of relocation may be protection of pollen from loss due to abiotic factors. In Campanulaceae pollen is presented on pollen-collecting hairs along the style and the hairs retract over time and release pollen for transfer. Campanulaceae taxa vary in the degree to which pollen is exposed to environmental factors due to variation in the corolla shape and size. We tested the protective function of pollen-collecting hairs by assessing whether there was a tradeoff between the protection provided by the corolla and the pollen-collecting hairs.</p><p><strong>Methods: </strong>We used phylogenetic comparative methods to test for associations between pollen-collecting hair length, floral shape and size metrics, and pollen exposure traits across 39 species.</p><p><strong>Results: </strong>We anticipated longer pollen-collecting hairs in taxa with more exposed pollen presentation but found there was no relationship between estimates of pollen exposure and pollen-collecting hair length. However, pollen-collecting hair length scaled allometrically with floral size, and variation in pollen-collecting hairs, as well as most floral traits, was phylogenetically structured.</p><p><strong>Conclusions: </strong>These results indicate that variation in pollen exposure across species does not structure variation in the pollen-collecting hairs, rather hair length scales allometrically and is phylogenetically constrained, therefore pollen-collecting hairs are unlikely to facilitate protection from environmental pressures.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142124606","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}
I Gélvez-Zúñiga, M Beirão, S Novais, J C Santiago, G W Fernandes
Background and aims: Flower-visitor interactions comprise a continuum of behaviors, from mutualistic partners to antagonistic visitors. Despite being relatively frequent in natural communities, florivory remains unexplored, especially when comprising abiotic factors, spatio-temporal variations and global environmental changes. Here, we addressed the variation of florivory driven by changes in elevation and temporal flower availability. We expect decreased floral resources as elevation increases -due to environmental constraints- which may affect plant-florivore interactions. Yet, if floral resources decrease but florivores remain constant, then we may expect an increase in florivory with increasing elevation in the community.
Methods: The flowering phenology of plant individuals was recorded in the Neotropical campo rupestre vegetation, in southeastern Brazil. Damages by florivores were recorded in plots at elevations ranging from 823 to 1411 m using two response variables as a proxy for florivory: the proportion of attacked flowers per plant and the proportion of petal removal on single flowers.
Key results: Flower attack increased with elevation and damages were intensified in species with longer flowering periods. Conversely, longer flowering periods resulted in higher levels of petal removal when decreasing elevation. The temporal availability of flowers affected florivory, with the proportion of attacked flowers being more intense when there are less flowered individuals in the community. Petal removal on single flowers was intensified in plots with a larger number of individuals flowering, and with more species co-flowering.
Conclusions: This study brings one of the broadest records of a commonly neglected interaction of insects feeding on floral structures, quantifying the combined effect of floral display and availability along an elevation gradient in a highly biodiverse mountaintop community. These findings contribute to filling in the gap in the understanding of florivory dynamics, focusing on a tropical mountaintop scenario facing imminent environmental changes and excessive natural resource exploitation.
{"title":"Floral resource availability declines and florivory increases along an elevation gradient in a highly biodiverse community.","authors":"I Gélvez-Zúñiga, M Beirão, S Novais, J C Santiago, G W Fernandes","doi":"10.1093/aob/mcae155","DOIUrl":"https://doi.org/10.1093/aob/mcae155","url":null,"abstract":"<p><strong>Background and aims: </strong>Flower-visitor interactions comprise a continuum of behaviors, from mutualistic partners to antagonistic visitors. Despite being relatively frequent in natural communities, florivory remains unexplored, especially when comprising abiotic factors, spatio-temporal variations and global environmental changes. Here, we addressed the variation of florivory driven by changes in elevation and temporal flower availability. We expect decreased floral resources as elevation increases -due to environmental constraints- which may affect plant-florivore interactions. Yet, if floral resources decrease but florivores remain constant, then we may expect an increase in florivory with increasing elevation in the community.</p><p><strong>Methods: </strong>The flowering phenology of plant individuals was recorded in the Neotropical campo rupestre vegetation, in southeastern Brazil. Damages by florivores were recorded in plots at elevations ranging from 823 to 1411 m using two response variables as a proxy for florivory: the proportion of attacked flowers per plant and the proportion of petal removal on single flowers.</p><p><strong>Key results: </strong>Flower attack increased with elevation and damages were intensified in species with longer flowering periods. Conversely, longer flowering periods resulted in higher levels of petal removal when decreasing elevation. The temporal availability of flowers affected florivory, with the proportion of attacked flowers being more intense when there are less flowered individuals in the community. Petal removal on single flowers was intensified in plots with a larger number of individuals flowering, and with more species co-flowering.</p><p><strong>Conclusions: </strong>This study brings one of the broadest records of a commonly neglected interaction of insects feeding on floral structures, quantifying the combined effect of floral display and availability along an elevation gradient in a highly biodiverse mountaintop community. These findings contribute to filling in the gap in the understanding of florivory dynamics, focusing on a tropical mountaintop scenario facing imminent environmental changes and excessive natural resource exploitation.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142118840","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}
Nian Zhou, Ke Miao, Luxiao Hou, Haiyang Liu, Jiahui Chen, Yunheng Ji
Background and aims: Previous phylogenetic studies on the pharmaceutically significant genus Paris (Melanthiaceae) have consistently revealed substantial cytonuclear discordance, yet the underlying mechanism responsible for this phenomenon remains elusive. This study aims to reconstruct a robust nuclear backbone phylogeny and elucidate the potential evolutionarily complex events contributing to previously observed cytonuclear discordance within Paris.
Methods: Based on a comprehensive set of nuclear low-copy orthologous genes obtained from transcriptomic data, the intrageneric phylogeny of Paris, along with its phylogenetic relationships to allied genera were inferred, using coalescent and concatenated approaches. The analysis of gene tree discordance and reticulate evolution, in conjunction with an incomplete lineage sorting (ILS) simulation, was conducted to explore potential hybridization and ILS events in the evolutionary history of Paris and assess their contribution to the discordance of gene trees.
Key results: The nuclear phylogeny unequivocally confirmed the monophyly of Paris and its sister relationship with Trillium, while widespread incongruences in gene trees were observed at the majority of internal nodes within Paris. The reticulate evolution analysis identified five instances of hybridization events in Paris, indicating that hybridization events might have recurrently occurred throughout the evolutionary history of Paris. In contrast, the ILS simulations revealed that only two internal nodes within sect. Euthyra experienced ILS events.
Conclusions: Our data suggest that the previously observed cytonuclear discordance in the phylogeny of Paris can primarily be attributed to recurrent hybridization events, with secondary contributions from infrequent ILS events. The recurrent hybridization events in the evolutionary history of Paris not only drove lineage diversification and speciation but also facilitated morphological innovation, and enhanced ecological adaptability. Therefore, artificial hybridization has great potential for breeding medicinal Paris species. These findings significantly contribute to our comprehensive understanding of the evolutionary complexity of this pharmaceutically significant plant lineage, thereby facilitating effective exploration and conservation efforts.
背景和目的:以前对具有重要药用价值的巴黎属(Melanthiaceae)进行的系统发育研究一直揭示了大量的胞核不一致性,但造成这种现象的潜在机制仍然难以捉摸。本研究旨在重建一个强大的核骨干系统发育,并阐明导致之前观察到的巴黎属细胞核不一致的潜在复杂进化事件:方法:基于从转录组数据中获得的一整套核低拷贝直向同源基因,利用聚合和连接方法推断了巴黎属的属内系统发育及其与同属的系统发育关系。结合不完全世系分类(ILS)模拟,对基因树的不一致性和网状进化进行了分析,以探索巴黎属进化史中潜在的杂交和 ILS 事件,并评估它们对基因树不一致性的影响:主要结果:核系统进化明确证实了巴黎树的单系性及其与三叶草的姊妹关系,而在巴黎树的大部分内部节点上观察到了基因树的广泛不一致性。网状进化分析在巴黎中发现了五次杂交事件,表明杂交事件可能在巴黎的整个进化历史中反复发生。与此相反,ILS模拟显示,在Euthyra科中只有两个内部节点经历了ILS事件。结论:我们的数据表明,之前观察到的巴黎龙系统发育中的细胞核不一致性主要归因于反复发生的杂交事件,其次才是不经常发生的 ILS 事件。巴黎鱼进化史中反复发生的杂交事件不仅推动了鱼系的多样化和物种的分化,还促进了形态创新,增强了生态适应性。因此,人工杂交在培育药用巴黎树种方面具有巨大潜力。这些发现大大有助于我们全面了解这一具有重要药用价值的植物品系的进化复杂性,从而促进有效的探索和保护工作。
{"title":"Phylotranscriptomic analyses reveal the evolutionary complexity of Paris L. (Melanthiaceae), a morphologically distinctive genus with significant pharmaceutical importance.","authors":"Nian Zhou, Ke Miao, Luxiao Hou, Haiyang Liu, Jiahui Chen, Yunheng Ji","doi":"10.1093/aob/mcae156","DOIUrl":"https://doi.org/10.1093/aob/mcae156","url":null,"abstract":"<p><strong>Background and aims: </strong>Previous phylogenetic studies on the pharmaceutically significant genus Paris (Melanthiaceae) have consistently revealed substantial cytonuclear discordance, yet the underlying mechanism responsible for this phenomenon remains elusive. This study aims to reconstruct a robust nuclear backbone phylogeny and elucidate the potential evolutionarily complex events contributing to previously observed cytonuclear discordance within Paris.</p><p><strong>Methods: </strong>Based on a comprehensive set of nuclear low-copy orthologous genes obtained from transcriptomic data, the intrageneric phylogeny of Paris, along with its phylogenetic relationships to allied genera were inferred, using coalescent and concatenated approaches. The analysis of gene tree discordance and reticulate evolution, in conjunction with an incomplete lineage sorting (ILS) simulation, was conducted to explore potential hybridization and ILS events in the evolutionary history of Paris and assess their contribution to the discordance of gene trees.</p><p><strong>Key results: </strong>The nuclear phylogeny unequivocally confirmed the monophyly of Paris and its sister relationship with Trillium, while widespread incongruences in gene trees were observed at the majority of internal nodes within Paris. The reticulate evolution analysis identified five instances of hybridization events in Paris, indicating that hybridization events might have recurrently occurred throughout the evolutionary history of Paris. In contrast, the ILS simulations revealed that only two internal nodes within sect. Euthyra experienced ILS events.</p><p><strong>Conclusions: </strong>Our data suggest that the previously observed cytonuclear discordance in the phylogeny of Paris can primarily be attributed to recurrent hybridization events, with secondary contributions from infrequent ILS events. The recurrent hybridization events in the evolutionary history of Paris not only drove lineage diversification and speciation but also facilitated morphological innovation, and enhanced ecological adaptability. Therefore, artificial hybridization has great potential for breeding medicinal Paris species. These findings significantly contribute to our comprehensive understanding of the evolutionary complexity of this pharmaceutically significant plant lineage, thereby facilitating effective exploration and conservation efforts.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103742","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}
Xu Liu, J Theo M Elzenga, Jan Henk Venema, Kira J Tiedge
Background: With soil salinity levels rising at an alarming rate, accelerated by climate change and human interventions, there is a growing need for crop varieties that can grow on saline soils. Alfalfa (Medicago sativa) is a cool-season perennial leguminous crop, commonly grown as forage, biofuel feedstock, and soil conditioner. It demonstrates significant potential for agricultural circularity and sustainability, for example by fixing nitrogen, sequestering carbon, and improving soil structures. Although alfalfa is traditionally regarded as moderately salt-tolerant species, modern alfalfa varieties display specific salt-tolerance mechanisms, which could be used to pave alfalfa's role as a leading crop able to grow on saline soils.
Scope: Alfalfa's salt tolerance underlies a large variety of cascading biochemical and physiological mechanisms. These are partly enabled by alfalfa's complex genome structure and out-crossing nature, which on the other hand entail impediments for molecular and genetic studies. This review first summarizes the general effects of salinity on plants and the broad-ranging mechanisms for dealing with salt-induced osmotic stress, ion toxicity, and secondary stress. Secondly, we address defensive and adaptive strategies that have been described for alfalfa, such as the plasticity of alfalfa's root system, hormonal crosstalk for maintaining ion homeostasis, spatiotemporal specialized metabolite profiles, and the protection of alfalfa-rhizobia associations. Finally, bottlenecks for research of the physiological and molecular salt-stress responses as well as biotechnology-driven improvements of salt tolerance are identified and discussed.
Conclusion: Understanding morpho-anatomical, physiological, and molecular responses to salinity is essential for the improvement of alfalfa and other crops in saline land reclamation. This review identifies potential breeding targets for enhancing alfalfa performance stability and general crop robustness for rising salt levels as well as to promote alfalfa applications in saline land management.
{"title":"Thriving in a salty future: morpho-anatomical, physiological, and molecular adaptations to salt stress in alfalfa (Medicago sativa L.) and other crops.","authors":"Xu Liu, J Theo M Elzenga, Jan Henk Venema, Kira J Tiedge","doi":"10.1093/aob/mcae152","DOIUrl":"https://doi.org/10.1093/aob/mcae152","url":null,"abstract":"<p><strong>Background: </strong>With soil salinity levels rising at an alarming rate, accelerated by climate change and human interventions, there is a growing need for crop varieties that can grow on saline soils. Alfalfa (Medicago sativa) is a cool-season perennial leguminous crop, commonly grown as forage, biofuel feedstock, and soil conditioner. It demonstrates significant potential for agricultural circularity and sustainability, for example by fixing nitrogen, sequestering carbon, and improving soil structures. Although alfalfa is traditionally regarded as moderately salt-tolerant species, modern alfalfa varieties display specific salt-tolerance mechanisms, which could be used to pave alfalfa's role as a leading crop able to grow on saline soils.</p><p><strong>Scope: </strong>Alfalfa's salt tolerance underlies a large variety of cascading biochemical and physiological mechanisms. These are partly enabled by alfalfa's complex genome structure and out-crossing nature, which on the other hand entail impediments for molecular and genetic studies. This review first summarizes the general effects of salinity on plants and the broad-ranging mechanisms for dealing with salt-induced osmotic stress, ion toxicity, and secondary stress. Secondly, we address defensive and adaptive strategies that have been described for alfalfa, such as the plasticity of alfalfa's root system, hormonal crosstalk for maintaining ion homeostasis, spatiotemporal specialized metabolite profiles, and the protection of alfalfa-rhizobia associations. Finally, bottlenecks for research of the physiological and molecular salt-stress responses as well as biotechnology-driven improvements of salt tolerance are identified and discussed.</p><p><strong>Conclusion: </strong>Understanding morpho-anatomical, physiological, and molecular responses to salinity is essential for the improvement of alfalfa and other crops in saline land reclamation. This review identifies potential breeding targets for enhancing alfalfa performance stability and general crop robustness for rising salt levels as well as to promote alfalfa applications in saline land management.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103745","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}
Ana Gálvez-Galván, Manuel A Garrido-Ramos, Pilar Prieto
Background and aims: Durum wheat, Triticum turgidum, and bread wheat, Triticum aestivum, are two allopolyploid species of very recent origin that have been subjected to intense selection programs during the thousands of years they have been cultivated. In this paper, we study the durum wheat satellitome and establish a comparative analysis with the previously published bread wheat satellitome.
Methods: We revealed the durum wheat satellitome using the satMiner protocol which is based on consecutive rounds of clustering of Illumina reads by RepeatExplorer2, and estimated abundance and variation for each identified satDNA with RepeatMasker v4.0.5. We have also performed a deep satDNA families characterization including chromosomal location by Fluorescence In Situ Hybridization (FISH) in durum wheat and its comparison with FISH patterns in bread wheat. Basic Local Alignment Search Tool (BLAST®) was used for trailing each satDNA in the assembly of durum wheat genome through NCBI's Genome Data Viewer (GDW) and the genome assemblies of both species were compared. Sequence divergence and consensus turnover rate (CTR) between homologous satDNA families of durum and bread wheat were estimated using MEGA11.
Key results: This study reveals that in an exceedingly short period, significant qualitative and quantitative changes have occurred in the set of satellite DNAs (satDNAs) of both species, with expansions/contractions of the number of repeats and the loci per satellite, different in each species, and a high rate of sequence change for most of these satellites, in addition to the emergence/loss of satDNAs not shared between the two species analysed. These evolutionary changes in satDNA are common between species but what is truly remarkable and novel about this study is that these processes have taken place in less than the last ~8000 years separating the two species, indicating an accelerated evolution of their satDNAs.
Conclusions: These results, together with the relationship of many of these satellites with transposable elements and the polymorphisms they generate at the level of centromeres and subtelomeric regions of their chromosomes, are analysed and discussed in the context of the evolutionary origin of these species and the selection pressure exerted by man throughout the history of their cultivation.
{"title":"The highly dynamic satellitomes of cultivated wheat species.","authors":"Ana Gálvez-Galván, Manuel A Garrido-Ramos, Pilar Prieto","doi":"10.1093/aob/mcae132","DOIUrl":"https://doi.org/10.1093/aob/mcae132","url":null,"abstract":"<p><strong>Background and aims: </strong>Durum wheat, Triticum turgidum, and bread wheat, Triticum aestivum, are two allopolyploid species of very recent origin that have been subjected to intense selection programs during the thousands of years they have been cultivated. In this paper, we study the durum wheat satellitome and establish a comparative analysis with the previously published bread wheat satellitome.</p><p><strong>Methods: </strong>We revealed the durum wheat satellitome using the satMiner protocol which is based on consecutive rounds of clustering of Illumina reads by RepeatExplorer2, and estimated abundance and variation for each identified satDNA with RepeatMasker v4.0.5. We have also performed a deep satDNA families characterization including chromosomal location by Fluorescence In Situ Hybridization (FISH) in durum wheat and its comparison with FISH patterns in bread wheat. Basic Local Alignment Search Tool (BLAST®) was used for trailing each satDNA in the assembly of durum wheat genome through NCBI's Genome Data Viewer (GDW) and the genome assemblies of both species were compared. Sequence divergence and consensus turnover rate (CTR) between homologous satDNA families of durum and bread wheat were estimated using MEGA11.</p><p><strong>Key results: </strong>This study reveals that in an exceedingly short period, significant qualitative and quantitative changes have occurred in the set of satellite DNAs (satDNAs) of both species, with expansions/contractions of the number of repeats and the loci per satellite, different in each species, and a high rate of sequence change for most of these satellites, in addition to the emergence/loss of satDNAs not shared between the two species analysed. These evolutionary changes in satDNA are common between species but what is truly remarkable and novel about this study is that these processes have taken place in less than the last ~8000 years separating the two species, indicating an accelerated evolution of their satDNAs.</p><p><strong>Conclusions: </strong>These results, together with the relationship of many of these satellites with transposable elements and the polymorphisms they generate at the level of centromeres and subtelomeric regions of their chromosomes, are analysed and discussed in the context of the evolutionary origin of these species and the selection pressure exerted by man throughout the history of their cultivation.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103744","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}
Background and aims: Each branch internode, and the organs growing on it, can be seen as a single morphological phytomer subunit, made of structurally and functionally interrelated components. However, allometric relationships between anatomy and morphology of these subunits remain unclear, particularly in the axial context. This study aims to address this knowledge gap, by measuring morpho-anatomical parameters and their allometric relationships along grapevine shoots.
Methods: To facilitate comparison, shoot length was normalized and a relative position index was calculated for each internode, ranging from 0 at the base to 1 at the apex. Scaling relationships between morpho-anatomical parameters along the axis were developed and validated by statistical modeling.
Key results: Most morpho-anatomical parameters displayed an axial behaviour of increasing then decreasing in size from base to apex, with the exception of shoot diameter and shoot vessel density. Relative position index of 0.2 acted as the data turning point for most variables analysed. During the first phase (relative position index below 0.2), the phytomer organs traits are uncoupled and show weak allometric correlation, and during the second phase the traits are strongly allometrically related.
Conclusions: Our findings suggest that allometric relationships along grapevine shoots are not constant- they exhibit a bimodal pattern, possibly influenced by seasonal temperatures. This work could aid managing productivity shifts in agricultural and natural systems under global climate change and add to basic knowledge of differentiation and development of growth units in plants.
{"title":"Bimodal pattern of allometric scaling along grapevine shoots.","authors":"Alaa Haj-Yahya, Yonatan Sorek, Uri Hochberg, Noa Ohana-Levi, Yotam Zait, Ilana Shtein","doi":"10.1093/aob/mcae146","DOIUrl":"https://doi.org/10.1093/aob/mcae146","url":null,"abstract":"<p><strong>Background and aims: </strong>Each branch internode, and the organs growing on it, can be seen as a single morphological phytomer subunit, made of structurally and functionally interrelated components. However, allometric relationships between anatomy and morphology of these subunits remain unclear, particularly in the axial context. This study aims to address this knowledge gap, by measuring morpho-anatomical parameters and their allometric relationships along grapevine shoots.</p><p><strong>Methods: </strong>To facilitate comparison, shoot length was normalized and a relative position index was calculated for each internode, ranging from 0 at the base to 1 at the apex. Scaling relationships between morpho-anatomical parameters along the axis were developed and validated by statistical modeling.</p><p><strong>Key results: </strong>Most morpho-anatomical parameters displayed an axial behaviour of increasing then decreasing in size from base to apex, with the exception of shoot diameter and shoot vessel density. Relative position index of 0.2 acted as the data turning point for most variables analysed. During the first phase (relative position index below 0.2), the phytomer organs traits are uncoupled and show weak allometric correlation, and during the second phase the traits are strongly allometrically related.</p><p><strong>Conclusions: </strong>Our findings suggest that allometric relationships along grapevine shoots are not constant- they exhibit a bimodal pattern, possibly influenced by seasonal temperatures. This work could aid managing productivity shifts in agricultural and natural systems under global climate change and add to basic knowledge of differentiation and development of growth units in plants.</p>","PeriodicalId":8023,"journal":{"name":"Annals of botany","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142103739","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}