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1.
Philos Trans R Soc Lond B Biol Sci ; 377(1853): 20210423, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35491589

RESUMO

Many environmental factors impact plant and pollinator communities. However, variation in soil moisture and how it mediates the plant-pollinator interactions has yet to be elucidated. We hypothesized that long-term variation in soil moisture can exert a strong selective pressure on the floral and vegetative traits of plants, leading to changes in pollinator visitation. We demonstrated that there are three phenotypic populations of Gentiana aristata in our study alpine region in the Qinghai-Tibetan Plateau that vary in floral colour and other traits. Pink (dry habitat) and blue (intermediate habitat) flower populations are visited primarily by bumblebees, and white (wet habitat) flower populations are visited by flies. These patterns of visitation are driven by vegetative and floral traits and are constant when non-endemic plants are placed in the intermediate habitats. Additionally, the floral communities in different habitats vary, with more insect-pollinated forbs in the dry and intermediate habitats versus the wet habitats. Through a common garden and reciprocal transplant experiment, we demonstrated that plant growth traits, pollinator attractiveness and seed production are highest when the plant population is raised in its endemic habitat. This suggests that these plant populations have evolved to pollinator communities associated with habitat differences. This article is part of the theme issue 'Natural processes influencing pollinator health: from chemistry to landscapes'.


Assuntos
Magnoliopsida , Animais , Flores , Plantas , Polinização , Solo
2.
Zootaxa ; 5123(1): 1-172, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35391141

RESUMO

We present a revision of the Clavatulidae gastropods of the Neogene of the Central and Eastern Paratethys seas. In total, 111 species level names have been used in the literature for Clavatulidae of the Paratethys Sea. After revision, we document 83 species. Seventeen genus-level groups are recognized, of which eleven are formally described. Six species-groups cannot be clearly placed in a certain Clavatulidae genus. The presence of Clavatula, Perrona, Pusionella, Scaevatula and Tomellana in the Paratethyan assemblages documents a biogeographic relationship with extant Clavatulidae faunas from the tropical eastern Atlantic. No Indo-West Pacific influences were observed, as Paratethyan species previously placed in Turricula, which belongs within the Clavatulidae, do not belong within that genus. The Langhian (middle Miocene) diversity of 62 species is comparable to the number of extant species recorded from West Africa (~65 species), but displays a much higher diversity at genus level. This high biodiversity in Paratethyan assemblages suggests that the Central Paratethys was a major center of radiation for clavatulid gastropods, which is also expressed by a high endemicity of 98.8%. In contrast, the clavatulid diversity in the Eastern Paratethys was very low and stratigraphically restricted to the early Miocene Sakaraulian. Granulatocincta nov. gen., Megaclavatula nov. gen., Neoperrona nov. gen., Olegia nov. gen., Striopusionella nov. gen. are established as new genera. Clavatula sorini nov. sp., Clavatula irisae nov. sp., Tomellana dulaii nov. sp., Tomellana aueri nov. sp., Granulatocincta callim nov. sp., Granulatocincta theoderichi nov. sp., Megaclavatula grunerti nov. sp., Megaclavatula pilleri nov. sp., Neoperrona zoltanorum nov. sp., Olegia mandici nov. sp., Perrona koeberli nov. sp., Perrona loetschi nov. sp., Pusionella hofmanni nov. sp. are described as new species from the Miocene Paratethys, and Clavatula ariejansseni nov. sp., Clavatula atatuerki nov. sp. and Granulatocincta pelliscrocodili nov. sp., are described from the eastern Proto-Mediterranean Karaman Basin of Turkey. Clavatula jarzynkae nov. nom., Perrona grossi nov. nom., Perrona ilonae nov. nom. and Perrona wanzenboecki nov. nom. are introduced as new names for Clavatula auingeri Finlay, 1927 [non Hilber, 1879], Pleurotoma (Clavatula) auingeri Hilber, 1879 [non Hoernes, 1875], Clavatula vindobonensis nodosa Csepreghy-Meznerics, 1954 [non Bellardi, 1847] and Pleurotoma concinna Handmann, 1883 [non Scacchi, 1836] respectively. Clavatula kowalewskii Bauk, 2003, Clavatula letksensis Csepreghy-Meznerics, 1953, Pleurotoma aculeatum Eichwald, 1830, Pleurotoma subscalaris Handmann, 1882 and Pleurotoma (Clavatula) reginae Hoernes Auinger, 1891 are treated as junior subjective synonyms of Pleurotoma (Clavatula) antoniae Hoernes Auinger, 1891, Perrona emmae (Hoernes Auinger, 1879), Pleurotoma laevigata Eichwald, 1830, Pleurotoma schreibersi Hrnes, 1854 and Pleurotoma (Clavatula) apolloniae Hoernes Auinger, 1891 respectively.


Assuntos
Gastrópodes , Magnoliopsida , Animais , Biodiversidade , Fósseis
3.
Genes (Basel) ; 13(4)2022 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-35456376

RESUMO

In angiosperms, huge advances in massive DNA sequencing technologies have impacted phylogenetic studies. Probe sets have been developed with the purpose of recovering hundreds of orthologous loci of targeted DNA sequences (TDS) across different plant lineages. We tested in silico the effectiveness of two universal probe sets in the whole available genomes of Caryophyllids, emphasizing phylogenetic issues in cacti species. A total of 870 TDS (517 TDS from Angiosperm v.1 and 353 from Angiosperms353) were individually tested in nine cacti species and Amaranthus hypochondriacus (external group) with ≥17 Gbp of available DNA data. The effectiveness was measured by the total number of orthologous loci recovered and their length, the percentage of loci discarded by paralogy, and the proportion of informative sites (PIS) in the alignments. The results showed that, on average, Angiosperms353 was better than Angiosperm v.1 for cacti species, since the former obtained an average of 275.6 loci that represent 123,687 bp, 2.48% of paralogous loci, and 4.32% of PIS in alignments, whereas the latter recovered 148.4 loci (37,683 bp), 10.38% of paralogous loci, and 3.49% of PIS. We recommend the use of predesigned universal probe sets for Caryophyllids, since these recover a high number of orthologous loci that resolve phylogenetic relationships.


Assuntos
Cactaceae , Magnoliopsida , Cactaceae/genética , Genoma , Magnoliopsida/genética , Filogenia , Análise de Sequência de DNA/métodos
4.
Genes (Basel) ; 13(4)2022 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-35456467

RESUMO

BACKGROUND: Nitraria sibirica Pall. is one of the pioneer tree species in saline-alkali areas due to its extreme salt tolerance. However, the lack of information on its genome limits the further exploration of the molecular mechanisms in N. sibirica under salt stress. METHODS: In this study, we used single-molecule real-time (SMRT) technology based on the PacBio Iso-Seq platform to obtain transcriptome data from N. sibirica under salt treatment for the first time, which is helpful for our in-depth analysis of the salt tolerance and molecular characteristics of N. sibirica. RESULTS: Our results suggested that a total of 234,508 circular consensus sequences (CCSs) with a mean read length of 2121 bp were obtained from the 19.26 Gb raw data. Furthermore, based on transcript cluster analysis, 93,713 consensus isoforms were obtained, including 92,116 high-quality isoforms. After removing redundant sequences, 49,240 non-redundant transcripts were obtained from high-quality isoforms. A total of 37,261 SSRs, 1816 LncRNAs and 47,314 CDSs, of which 40,160 carried complete ORFs, were obtained. Based on our transcriptome data, we also analyzed the coding genes of H+-PPase, and the results of both bioinformatics and functional analyses indicated that the gene prediction via full-length transcripts obtained by SMRT technology is reliable and effective. In summary, our research data obtained by SMRT technology provides more reliable and accurate information for the further analysis of the regulatory network and molecular mechanism of N. sibirica under salt stress.


Assuntos
Magnoliopsida , Plantas Tolerantes a Sal , Perfilação da Expressão Gênica/métodos , Magnoliopsida/genética , Isoformas de Proteínas/genética , Tolerância ao Sal , Plantas Tolerantes a Sal/genética
5.
Mol Biol Evol ; 39(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35383845

RESUMO

Whole-genome duplications (WGDs) are a prominent process of diversification in eukaryotes. The genetic and evolutionary forces that WGD imposes on cytoplasmic genomes are not well understood, despite the central role that cytonuclear interactions play in eukaryotic function and fitness. Cellular respiration and photosynthesis depend on successful interaction between the 3,000+ nuclear-encoded proteins destined for the mitochondria or plastids and the gene products of cytoplasmic genomes in multi-subunit complexes such as OXPHOS, organellar ribosomes, Photosystems I and II, and Rubisco. Allopolyploids are thus faced with the critical task of coordinating interactions between the nuclear and cytoplasmic genes that were inherited from different species. Because the cytoplasmic genomes share a more recent history of common descent with the maternal nuclear subgenome than the paternal subgenome, evolutionary "mismatches" between the paternal subgenome and the cytoplasmic genomes in allopolyploids might lead to the accelerated rates of evolution in the paternal homoeologs of allopolyploids, either through relaxed purifying selection or strong directional selection to rectify these mismatches. We report evidence from six independently formed allotetraploids that the subgenomes exhibit unequal rates of protein-sequence evolution, but we found no evidence that cytonuclear incompatibilities result in altered evolutionary trajectories of the paternal homoeologs of organelle-targeted genes. The analyses of gene content revealed mixed evidence for whether the organelle-targeted genes are lost more rapidly than the non-organelle-targeted genes. Together, these global analyses provide insights into the complex evolutionary dynamics of allopolyploids, showing that the allopolyploid subgenomes have separate evolutionary trajectories despite sharing the same nucleus, generation time, and ecological context.


Assuntos
Magnoliopsida , Núcleo Celular/genética , Evolução Molecular , Genoma de Planta , Magnoliopsida/genética , Plastídeos/genética , Poliploidia , Ribulose-Bifosfato Carboxilase/genética
6.
BMC Ecol Evol ; 22(1): 45, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35413792

RESUMO

BACKGROUND: Keel flowers are bilaterally symmetrical, pentamerous flowers with three different petal types and reproductive organs enclosed by keel petals; generally there is also connation of floral parts such as stamens and keel petals. In this study, the evolution of keel flowers within the order Fabales is explored to investigate whether the establishment of this flower type within one of the species-rich families, the Fabaceae (Leguminosae), preceded and could have influenced the evolution of keel flowers in the Polygalaceae. We conducted molecular dating, and ancestral area and ancestral state analyses for a phylogeny constructed for 678 taxa using published matK, rbcL and trnL plastid gene regions. RESULTS: We reveal the temporal and spatial origins of keel flowers and traits associated with pollinators, specifically floral symmetry, the presence or absence of a pentamerous corolla and three distinct petal types, the presence or absence of enclosed reproductive organs, androecium types, inflorescence types, inflorescence size, flower size, plant height and habit. Ancestral area reconstructions show that at the time keel flowers appeared in the Polygaleae, subfamily Papilionoideae of the Fabaceae was already distributed almost globally; at least eight clades of the Papilionoideae had keel flowers with a functional morphology broadly similar to the morphology of the first evolving Polygaleae flowers. CONCLUSIONS: The multiple origins of keel flowers within angiosperms likely represent convergence due to bee specialization, and therefore pollinator pressure. In the case of the Fabales, the first evolving keel flowers of Polygaleae have a functional morphology that corresponds with keel flowers of species of the Papilionoideae already present in the environment. These findings are consistent with the keel-flowered Polygaleae exploiting pollinators of keel-flowered Papilionoideae. The current study is the first to use ancestral reconstructions of traits associated with pollination to demonstrate that the multiple evolutionary origins of the keel flower pollinator syndrome in Fabales are consistent with, though do not prove, mimicry.


Assuntos
Fabaceae , Magnoliopsida , Animais , Abelhas , Fabaceae/anatomia & histologia , Flores/genética , Humanos , Filogenia , Polinização/genética
7.
Elife ; 112022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35416148

RESUMO

Worldwide, hoverflies (Syrphidae: Diptera) provide crucial ecosystem services such as pollination and biological pest control. Although many hoverfly species exhibit migratory behavior, the spatiotemporal facets of these movement dynamics, and their ecosystem services implications are poorly understood. In this study, we use long-term (16-year) trapping records, trajectory analysis, and intrinsic (i.e., isotope, genetic, pollen) markers to describe migration patterns of the hoverfly Episyrphus balteatus in northern China. Our work reveals how E. balteatus migrate northward during spring-summer and exhibits return (long-range) migration during autumn. The extensive genetic mixing and high genetic diversity of E. balteatus populations underscore its adaptive capacity to environmental disturbances, for example, climate change. Pollen markers and molecular gut analysis further illuminate how E. balteatus visits min. 1012 flowering plant species (39 orders) over space and time. By thus delineating E. balteatus transregional movements and pollination networks, we advance our understanding of its migration ecology and facilitate the design of targeted strategies to conserve and enhance its ecosystem services.


Assuntos
Dípteros , Magnoliopsida , Animais , Dípteros/genética , Ecossistema , Pólen , Polinização
8.
Int J Mol Sci ; 23(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35409113

RESUMO

In the course of evolution, both flowering plants and some gymnosperms have developed such an adaptation to winter and unfavorable living conditions as deciduousness. Of particular interest is Siberian larch (Larix sibirica Ledeb.), which is the only species in the pine family (Pinaceae) with a seasonal deciduousness. New generation sequencing technologies make it possible to study this phenomenon at the genomic level and to reveal the genetic mechanisms of leaf and needle aging in angiosperms and gymnosperms. Using a comparative analysis of the genomes of evergreen and deciduous trees, it was found that the genes that control EXORDIUM LIKE 2 (EXL2) and DORMANCY-ASSOCIATED PROTEIN 1 (DRM1) proteins are most represented in Siberian larch, while an excess of genes that control proteins acting as immune receptors were found in evergreens. Orthologs from the family of genes that control leucine-rich repeat receptor-like kinases (LRR-RLK) contributed mostly to the distinction between evergreens and deciduous plants.


Assuntos
Larix , Magnoliopsida , Traqueófitas , Florestas , Genômica , Larix/genética , Estações do Ano , Árvores/genética
9.
Mol Biol Evol ; 39(5)2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35438770

RESUMO

Land plants first evolved from freshwater algae, and flowering plants returned to water as early as the Cretaceous and multiple times subsequently. Alismatales is the largest clade of aquatic angiosperms including all marine angiosperms, as well as terrestrial plants. We used Alismatales to explore plant adaptations to aquatic environments by analyzing a data set that included 95 samples (89 Alismatales species) covering four genomes and 91 transcriptomes (59 generated in this study). To provide a basis for investigating adaptations, we assessed phylogenetic conflict and whole-genome duplication (WGD) events in Alismatales. We recovered a relationship for the three main clades in Alismatales as (Tofieldiaceae, Araceae) + core Alismatids. We also found phylogenetic conflict among the three main clades that was best explained by incomplete lineage sorting and introgression. Overall, we identified 18 putative WGD events across Alismatales. One of them occurred at the most recent common ancestor of core Alismatids, and three occurred at seagrass lineages. We also found that lineage and life-form were both important for different evolutionary patterns for the genes related to freshwater and marine adaptation. For example, several light- or ethylene-related genes were lost in the seagrass Zosteraceae, but are present in other seagrasses and freshwater species. Stomata-related genes were lost in both submersed freshwater species and seagrasses. Nicotianamine synthase genes, which are important in iron intake, expanded in both submersed freshwater species and seagrasses. Our results advance the understanding of the adaptation to aquatic environments and WGDs using phylogenomics.


Assuntos
Alismatales , Magnoliopsida , Adaptação Fisiológica/genética , Alismatales/genética , Evolução Biológica , Magnoliopsida/genética , Filogenia , Plantas
10.
Nat Plants ; 8(3): 194-195, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35241828
11.
Philos Trans R Soc Lond B Biol Sci ; 377(1850): 20210216, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35306891

RESUMO

Here, we review the literature on sexual lability in dioecious angiosperm species with well-studied sex chromosomes. We distinguish three types of departures from strict dioecy, concerning either a minority of flowers in some individuals (leakiness) or the entire individual, which can constantly be bisexual or change sex. We found that for only four of the 22 species studied, reports of lability are lacking. The occurrence of lability is only weakly related to sex chromosome characteristics (number of sex-linked genes, age of the non-recombining region). These results contradict the naive idea that lability is an indication of the absence or the recent evolution of sex chromosomes, and thereby contribute to a growing consensus that sex chromosomes do not necessarily fix sex determination once and for all. We discuss some implications of these findings for the evolution of sex chromosomes, and suggest that more species with well-characterized lability should be studied with genomic data and tools. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.


Assuntos
Magnoliopsida , Evolução Molecular , Flores/genética , Humanos , Magnoliopsida/genética , Cromossomos Sexuais/genética
12.
J Ethnopharmacol ; 292: 115187, 2022 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-35288287

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Warburgia (family Canellaceae) is widely distributed over Afrotropical and Neotropical realms. Traditionally, W. salutaris (G. Bertol.) Chiov., and other Warburgia species are used as anti-inflammatory, antimalarial, antimicrobial, and for wound healing, and treating several skin complaints as well. Specifically, different extracts from W. salutaris were reported to possess diuretic, anti-inflammatory, and cytotoxic effects. AIM OF THE STUDY: This work aimed to investigate the phytochemical composition of an aqueous extract from W. salutaris bark, and evaluate its antioxidant and anti-aging activities in silico, in vitro, and in vivo. MATERIALS AND METHODS: HPLC-PDA-MS/MS was used to investigate the phytochemical components of the extract. The antioxidant potential of the extract was evaluated in vitro using DPPH and FRAP assays. The Caenorhabditis elegans nematodes model was adopted to investigate the antioxidant and the anti-aging effects in vivo by determining the worms' survival rate, level of ROS, HSP16 expression, and nuclear translocation of the transcription factor DAF16. Molecular operating environment (MOE) software was utilized for in silico molecular docking of the extract's components into different enzymes involved in the aging process. Anti-collagenase, anti-elastase, anti-tyrosinase, and anti-hyaluronidase assays were used to evaluate the anti-aging effects in vitro. RESULTS: HPLC-MS analysis furnished 30 compounds, among them catechin, 11α-hydroxy muzigadiolide, mukaadial, pereniporin B, and 11α-hydroxycinnamosmolide. The major components of the extract showed appropriate fitting in the binding site of the target enzymes adopted in the study with considerable minimum free binding energy relative to the standard inhibitors. The extract showed substantial in vitro antioxidant activity in DPPH and FRAP assays and in vitro anti-aging assays against collagenase, elastase, tyrosinase, and hyaluronidase with comparable IC50 values to the reference standards. Moreover, it attenuated oxidative stress in vivo as it significantly increased the survival rate of ROS stressed C. elegans worms, decreased intracellular ROS, decreased the juglone-induced HSP16 expression and enhanced the nuclear localization of DAF16 in a dose-dependent manner. CONCLUSION: Our results support the traditional use of W. salutaris to counteract inflammation and oxidative stress associated with several pathological conditions. In addition, W. salutaris bark extract can be considered as a substantial source for bioactive metabolites with strong potential as anti-aging and antioxidant agents.


Assuntos
Antioxidantes , Magnoliopsida , Envelhecimento , Animais , Antioxidantes/uso terapêutico , Caenorhabditis elegans , Magnoliopsida/química , Simulação de Acoplamento Molecular , Compostos Fitoquímicos/farmacologia , Casca de Planta/química , Extratos Vegetais/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas em Tandem
13.
Nat Plants ; 8(3): 217-224, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35301445

RESUMO

In flowering plants, different lineages have independently transitioned from the ancestral hermaphroditic state into and out of various sexual systems1. Polyploidizations are often associated with this plasticity in sexual systems2,3. Persimmons (the genus Diospyros) have evolved dioecy via lineage-specific palaeoploidizations. More recently, hexaploid D. kaki has established monoecy and also exhibits reversions from male to hermaphrodite flowers in response to natural environmental signals (natural hermaphroditism, NH), or to artificial cytokinin treatment (artificial hermaphroditism, AH). We sought to identify the molecular pathways underlying these polyploid-specific reversions to hermaphroditism. Co-expression network analyses identified regulatory pathways specific to NH or AH transitions. Surprisingly, the two pathways appeared to be antagonistic, with abscisic acid and cytokinin signalling for NH and AH, respectively. Among the genes common to both pathways leading to hermaphroditic flowers, we identified a small-Myb RADIALIS-like gene, named DkRAD, which is specifically activated in hexaploid D. kaki. Consistently, ectopic overexpression of DkRAD in two model plants resulted in hypergrowth of the gynoecium. These results suggest that production of hermaphrodite flowers via polyploidization depends on DkRAD activation, which is not associated with a loss-of-function within the existing sex determination pathway, but rather represents a new path to (or reinvention of) hermaphroditism.


Assuntos
Diospyros , Transtornos do Desenvolvimento Sexual , Magnoliopsida , Diospyros/genética , Flores/genética , Poliploidia
14.
Phytochemistry ; 198: 113153, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35240134

RESUMO

From the leaves of Kenyan medicinal plant Bersama abyssinica Subspecies abyssinica, four previously undescribed compounds namely, three bufadienolides, 10ß-formylpaulliniogenin B, 10ß-formylpaulliniogenin A and 1ß-acetoxy-3ß,5ß-dihydroxy-15-methoxy-16,19-dioxobufa-14(15),20,22-trienolide, and a phenolic compound 2,6,4'-trihydroxybenzophenone-4-O-(6‴-cinnamoyl)-ß-D-glucoside were isolated together with four known compounds. The structural elucidation of the compounds was based on 1D and 2D NMR spectroscopy and HRMS data analyses. The relative configurations were defined by NOESY correlations. Cytotoxic activities on L929 and KB3.1 cell lines of the isolated compounds were investigated using MTT assay. The 1ß-acetoxy-3ß,5ß-dihydroxy-15-methoxy-16,19-dioxobufa-14(15),20,22-trienolide showed significant cytotoxic activity against KB3.1 cell lines with IC50 of 3.9 ± 0.99 µM.


Assuntos
Antineoplásicos , Bufanolídeos , Magnoliopsida , Plantas Medicinais , Bufanolídeos/análise , Bufanolídeos/química , Linhagem Celular Tumoral , Quênia , Magnoliopsida/química , Folhas de Planta/química
15.
Sci Rep ; 12(1): 5040, 2022 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-35322034

RESUMO

Early Cretaceous floras containing angiosperms were described from several geographic areas, nearly from the Arctic to the Antarctic, and are crucial to understand their evolution and radiation. However, most of these records come from northern mid-latitudes whereas those of lower paleolatitude areas, such as the Crato Fossil Lagerstätte in NE Brazil, are less studied. Here, we describe from this region of northern Gondwanan origin, two fossil-species of eudicots belonging to a new extinct genus Santaniella gen. nov. Together with several vegetative axes and leaves, anatomically well-preserved fruits with seeds and persistent perianth-like organs allowed us to reconstruct its potential affinities with ranunculids, and presumably Ranunculaceae. Previous records putatively assigned to Ranunculales are all from mid-latitudes, and their first unequivocal occurrence in a low-latitude area supports further the hypothesis of a widespread radiation of the earliest diverging eudicot lineage by this early age.


Assuntos
Fósseis , Magnoliopsida , Frutas , Folhas de Planta , Sementes
16.
Environ Entomol ; 51(2): 492-504, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35298611

RESUMO

Over the past century, habitat loss from agricultural intensification has contributed to pollinator decline. One way to mitigate the harmful effects of agricultural intensification is through the re-introduction of native flowering plants as border strips that provide supplemental floral and nesting resources to pollinators. However, border crop species vary in bloom period and flower densities, and are thus likely to attract different suites of pollinator species. Resulting differences in pollinator community composition are likely to affect their ability to provide pollination services to adjacent crop habitat. To address these issues, we implemented a two-year study on the impact of different flowering border crops on pollinator abundance, richness, and community composition. We also examined which crop features (bloom duration, number of flowers, floral area) were most likely to affect pollinator densities. We found that native flowering plant border crops of diverse prairie mix and monocultures of silflower (Silphium integrifolium Michx.) and cup plant (Silphium perfoliatum L.) attracted the highest abundance and species richness of bees and pollinator groups combined, while alfalfa (Medicago sativa L.) attracted the highest lepidopteran abundance and species richness. We also found a significant, positive relationship between pollinator abundance and floral resource amount and bloom duration. These findings offer valuable insight into the impacts of different land management strategies on different pollinator groups, and thus provide landowners with management options for attracting specific pollinator groups and species.


Assuntos
Magnoliopsida , Polinização , Agricultura/métodos , Animais , Abelhas , Produtos Agrícolas , Ecossistema , Flores , Medicago sativa
17.
Sci Rep ; 12(1): 4142, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35264735

RESUMO

The pollen and orbicule morphology of the Korean Piperales (Aristolochia, Asarum, Houttuynia, Piper, and Saururus) were investigated via scanning electron microscopy. Piperales pollen is a monad, its size ranging from very small to large (P = 7.78-51.4 µm, E = 6.68-43.1 µm), and having a mainly circular to sub-circular shape. The aperture type is constant in the genus [inaperturate (Aristolochia), tri to pentaporate (Asarum), and monosulcate (Houttuynia, Piper, and Saururus)]. There are four distinct types of exine ornamentation: Fossulate with perforate, microreticulate with gemmae, microperforate with granula, and microechinate. The orbicules (minute sporopollenin granules) were observed in all studied taxa and thus, may be a possible symplesiomorphic characteristic of Piperales. Further, the observed orbicule surface ornamentation was similar to pollen exine patterns, for example muri, gemmae, or granula. This resemblance between orbicule and pollen exine ornamentation may imply a similar biosynthesis pattern of sporopollenin of pollen exine and orbicules. The phenogram resulting from a cluster analysis using palynological characters was generally consistent with the known molecular phylogeny of Piperales. This initial study will help understand the palynological diversity and provide detailed information of pollen and orbicule characteristics in Piperales.


Assuntos
Aristolochia , Asarum , Magnoliopsida , Microscopia Eletrônica de Varredura , Filogenia , Pólen/anatomia & histologia , República da Coreia
18.
Am J Bot ; 109(4): 535-549, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35266560

RESUMO

PREMISE: Nonstructural carbohydrates (NSCs) play a key role in tree performance and functioning and are stored in radial and axial parenchyma (RAP) cells. Whether this relationship is altered among species and climates or is linked to functional traits describing xylem structure (wood density) and tree stature is not known. METHODS: In a systematic review, we collated data for NSC content and the proportion of RAP in stems for 68 tree species. To examine the relationships of NSCs and RAP with climatic factors and other functional traits, we also collected climatic data at each tree's location, as well as wood density and maximum height. A phylogenetic tree was constructed to examine the influence of species' evolutionary relationships on the associations among NSCs, RAP, and functional traits. RESULTS: Across all 68 tree species, NSCs were positively correlated with RAP and mean annual temperature, but relationships were only weakly significant in temperate species and angiosperms. When separating RAP into radial parenchyma (RP) and axial parenchyma (AP), both NSCs and wood density were positively correlated with RP but not with AP. Wood in taller trees was less dense and had lower RAP than in shorter trees, but height was not related to NSCs. CONCLUSIONS: In trees, NSCs are stored mostly in the RP fraction, which has a larger surface area in warmer climates. Additionally, NSCs were only weakly linked to wood density and tree height. Our analysis of evolutionary relationships demonstrated that RAP fractions and NSC content were always closely related across all 68 tree species, suggesting that RAP can act as a reliable proxy for potential NSC storage capacity in tree stems.


Assuntos
Magnoliopsida , Xilema , Carboidratos , Filogenia , Madeira
19.
Int J Mol Sci ; 23(6)2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35328537

RESUMO

Flowering is an important link in the life process of angiosperms, and it is also an important sign of the transformation of plants from vegetative to reproductive growth. Although the flowering regulation network of Arabidopsis is well-understood, there has been little research on the molecular mechanisms of perennial woody plant flower development regulation. Populus tomentosa is a unique Chinese poplar species with fast growth, strong ecological adaptability, and a long lifecycle. However, it has a long juvenile phase, which seriously affects its breeding process. Nuclear factor-Y (NF-Y) is an important type of transcription factor involved in the regulation of plant flowering. However, there are few reports on PtoNF-Y gene flowering regulation, and the members of the PtNF-YC subfamily are unknown. In this study, four key genes were cloned and analyzed for sequence characteristics, gene structure, genetic evolution, expression patterns, and subcellular localization. The plant expression vector was further constructed, and transgenic Arabidopsis and P. tomentosa plants were obtained through genetic transformation and a series of molecular tests. The flowering time and other growth characteristics were analyzed. Finally, the expression level of flowering genes was detected by quantitative PCR, the interaction between PtoNF-YC and PtoCOL proteins was measured using the yeast two-hybrid system to further explain the flowering regulation mechanism, and the molecular mechanisms by which PtNF-YC6 and PtNF-YC8 regulate poplar flowering were discussed. These results lay the foundation for elucidating the molecular regulation mechanism of PtoNF-YC in flowering and furthering the molecular design and breeding of poplar, while providing a reference for other flowering woody plants.


Assuntos
Arabidopsis , Magnoliopsida , Populus , Arabidopsis/metabolismo , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Magnoliopsida/genética , Filogenia , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Populus/metabolismo
20.
Philos Trans R Soc Lond B Biol Sci ; 377(1850): 20210228, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35306886

RESUMO

The genus Silene brings many opportunities for the study of various processes involved in the evolution of dioecy and young sex chromosomes. Here we focus on a dioecious clade in Silene subgenus Silene and closely related species. This study provides improved support for monophyly of this clade (based on inclusion of further dioecious species) and a new estimate of its age (ca 2.3 million years). We observed a rise in adaptive evolution in the autosomal and pseudoautosomal parts of the genome on the branch where dioecy originated. This increase is not a result of the accumulation of sexually antagonistic genes in the pseudoautosomal region. It is also not caused by the coevolution of genes acting in mitochondria (despite the possibility that dioecy along this branch could have evolved from a nucleo-cytoplasmic male sterility-based system). After considering other possibilities, the most parsimonious explanation for the increase seen in the number of positively selected codons is the adaptive evolution of genes involved in the adaptation of the autosomal part of the genome to dioecy, as described in Charnov's sex-allocation theory. As the observed coincidence cannot prove causality, studies in other dioecious clades are necessary to allow the formation of general conclusions. This article is part of the theme issue 'Sex determination and sex chromosome evolution in land plants'.


Assuntos
Magnoliopsida , Silene , Cromossomos de Plantas , Evolução Molecular , Cromossomos Sexuais , Silene/genética
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