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1.
Sci Total Environ ; 735: 139537, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32485454

RESUMO

While changing climatic conditions may directly impact species distribution ranges, indirect effects related to altered biotic interactions may exacerbate range shifts. This situation fully applies to epiphytic lichens that are sensitive to climatic factors and strongly depend on substrate occurrence and features for their dispersal and establishment. In this work, we modelled the climatic suitability across Italy under current and future climate of the forest species Lobaria pulmonaria, the lung lichen. Comparatively, we modelled the suitability of its main tree species in Italy, as well as that of the alien tree Robinia pseudoacacia, black locust, whose spread may cause the decline of many forest lichen species. Our results support the view that climate change may cause range shifts of epiphytes by altering the spatial pattern of their climatic suitability (direct effect) and simultaneously causing range shifts of their host-tree species (indirect effect). This phenomenon seems to be emphasized by the invasion of alien trees, as in the case of black locust, that may replace native host tree species. Results indicate that a reduction of the habitat suitability of the lung lichen across Italy should be expected in the face of climate change and that this is coupled with a loss of suitable substrate. This situation seems to be determined by two main processes that act simultaneously: 1) a partial reduction of the spatial overlap between the climatic niche of the lung lichen and that of its host tree species, and 2) the invasion of native woods by black locust. The case of lung lichen and black locust in Italy highlights that epiphytes are prone to both direct and indirect effects of climate change. The invasion of alien trees may have consequences that are still poorly evaluated for epiphytes.


Assuntos
Líquens , Robinia , Mudança Climática , Ecossistema , Itália , Árvores
2.
Sci Total Environ ; 727: 138739, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32498192

RESUMO

Whether or not the completely destroyed ecosystem would follow a succession trajectory towards the surrounding forest ecosystem after restoration remains debatable. Here, a comprehensive dataset of thirty-five ecosystem functions were measured on five reclaimed opencast coal mine forest plots (two Robinia pseudoacacia - Pinus tabuliformis mixed forests with different technosol conditions: RPT and RPM; one R. pseudoacacia - Ulmus pumila - Ailanthus altissima mixed forest: RUA; one Picea meyeri - Picea wilsonii - Hippophae rhamnoides mixed forest: PPH; one R. pseudoacacia monoculture forest: RM) and one natural forest plot (Populus simonii monoculture forest: PM) in Pingshuo opencast coal mine, Shanxi Province, China. These functions were employed to examine the reclamation effects among plots in terms of four management scenarios (i.e., biomass productivity, carbon sequestration, general biodiversity conservation and nutrient accumulation) and to determine the affinities between reclaimed ecosystem and its native counterpart according to Bray Curtis Distance Algorithm. The results showed that after 20-23 years of succession, thirty-five ecosystem functions differed among plots and eight highest ecosystem functions were found in RPT and RPM (P < 0.05). In scenarios of biomass productivity, carbon sequestration, general biodiversity conservation and nutrient accumulation scenarios, RPM scored 0.645, 0.470, 0.467 and 0.578, respectively. Accordingly, RPT scored 0.458, 0.447, 0.405 and 0.515, respectively. Consequently, RPT and RPM had the highest scores in the four management objectives compared to other plots. With regard to the ecosystem affinities, RPT was analogous to RPM. Similarly, RUA and PPH resembled PM and RM, respectively. Overall, the pioneer tree species determined the reclamation quality in the dump in the long term, which could be referred as the "trigger effect" in the succession trajectory in reclaimed ecosystem, and the reclaimed coal mine ecosystem diverged from the surrounding ecosystem and reached a new self-sustaining state after 20-23 years of succession.


Assuntos
Ecossistema , Robinia , China , Carvão Mineral , Mineração , Solo , Fatores de Tempo , Árvores
3.
J Environ Manage ; 268: 110558, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32383654

RESUMO

Afforestation has been proven to have enormous potential for carbon (C) sequestration; however, the dynamics of aggregate-associated organic carbon (OC) following afforestation and their contribution to changes in bulk soil OC are not well understood in regions with serious soil erosion. Therefore, we investigated the dynamics of OC associated with aggregates along a Robinia pseudoacacia (RP) afforestation chronosequence in the Loess Plateau. Soil aggregate size distribution and OC dynamics in bulk soil were analyzed 10, 18, 28, and 42 years after RP afforestation at depths of 0-20 cm and 20-40 cm. Results showed that total macroaggregates (>0.25 mm), mean weight diameter, and geometric mean diameter increased significantly with stand age, after 42 years of afforestation, increased by 433.5%, 437.2%, 302.1% in the 0-20 cm depth, respectively, while microaggregate amounts decreased by 52.9%, and the proportions of silt + clay fraction showed no obvious changes. Long-term afforestation increased OC content and stock, both in bulk soil (245.6% and 222.9% in the 0-20 cm depth, respectively) and soil aggregates. The improvement of soil structure and enrichment of OC stocks were greater at the 0-20 cm depth than the 20-40 cm depth. In addition, small macroaggregates (2-0.25 mm) contained the highest OC content and microaggregates (<0.025 mm) had the highest OC stocks regardless of soil depth and stand age. Across the afforestation chronosequence, OC content and stock in bulk soil positively correlated with large macroaggregate (>2 mm) amounts and small macroaggregate (2-0.25 mm) associated OC dynamics (P < 0.01). These results indicated that changes in bulk soil OC dynamics mainly depend on changes in the proportion of large macroaggregates and in the OC dynamics associated with small macroaggregates after RP afforestation.


Assuntos
Robinia , Carbono , Sequestro de Carbono , China , Solo
4.
Sci Total Environ ; 732: 139273, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32428772

RESUMO

Global warming may influence the bioavailability and mobility of heavy metals by stimulating or inhibiting plant growth, thereby influencing rhizosphere soil chemistry and microbial characteristics. Black locust has been widely planted in China as a promising species for afforestation programs, farmland shelterbelt projects, and soil restoration in mined areas because of its rapid growth and adaptability to environmental stressors. Here, we examined soil bacterial community structure and predicted bacterial metabolic function in the rhizosphere of black locust exposed to elevated temperature (+1.99 °C) and Pb for 4 years. Elevated temperature significantly (p < 0.05) reduced total carbon (TC), total nitrogen (TN), and total sulfur (TS) contents in above-ground parts but increased TC and TN contents in roots and seedling height under Pb exposure. Elevated temperature significantly (p < 0.05) increased Pb availability and raised pH, TC, TN, TS and water-soluble organic carbon (WSOC) contents, and the C:H ratio in rhizosphere soils under Pb exposure. The interactive effects between Pb and temperature on pH, TC, TH, TS, WSOC, and the C:H ratio were significant (p < 0.05). Elevated temperature significantly (p < 0.05) reduced the diversity and the richness of bacterial community, altered genus-level bacterial community composition, and improved (p < 0.05) the relative abundances of some bacteria involving in terpenoids and polyketides and xenobiotics biodegradation metabolism under Pb exposure. Canonical correspondence analysis indicated that pH, WSOC, C:N ratio, and soluble Pb were significant (p < 0.05) factors on the relative abundance of bacterial genera, such as Ochrobactrum and Sphingomnas. Overall, long-term elevated temperature resulted in changes in rhizosphere soil characteristics and Pb availability, thus affecting the bacterial community structure and metabolic functional groups. The conclusion helps us understand the response mechanism of soil bacteria in the rhizosphere to heavy metals under global warming scenarios.


Assuntos
Robinia , China , Rizosfera , Plântula , Solo , Microbiologia do Solo , Poluentes do Solo , Temperatura
5.
Ecotoxicol Environ Saf ; 197: 110563, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32278824

RESUMO

Sodium sulfide (Na2S) is usually used as an amendment in industrial sewage treatment. To evaluate the effects of Na2S on the growth of Robinia pseudoacacia (black locust), heavy metal immobilization, and soil microbial activity, the R. pseudoacacia biomass and nutrient content and the soil heavy metal bioavailability, enzyme activity, and arbuscular mycorrhizal (AM) fungal community were measured by a single-factor pot experiment. The Pb-Zn-contaminated soil was collected from a Pb-Zn mine that had been remediated by R. pseudoacacia for five years. Three pollution levels (unpolluted, mildly polluted, and severely polluted) were evaluated by the pollution load index. Na2S application increased the shoot biomass under severe and mild contamination. In soil, Na2S application decreased the bioavailable Pb and Zn contents under severe and mild contamination, which resulted in a decrease in the Pb and Zn content in R. pseudoacacia. However, Na2S application did not affect the total Pb content per plant and enhanced the total Zn content per plant because of the higher biomass of the plants under Na2S application. Increased phosphatase activity and increased available phosphorous content may promote the uptake of phosphorus in R. pseudoacacia. Moreover, Na2S application is beneficial to the diversity of AM fungi under mild and severe pollution. Overall, Na2S application has great potential for enhancing soil heavy metal immobilization, enhancing soil microbial activity, and improving the growth of R. pseudoacacia in polluted soils. Therefore, Na2S is suitable for use in Pb-Zn remediation to ameliorate environmental heavy metal pollution.


Assuntos
Metais Pesados/farmacocinética , Robinia/crescimento & desenvolvimento , Microbiologia do Solo , Poluentes do Solo/farmacocinética , Sulfetos/farmacologia , Biodegradação Ambiental , Disponibilidade Biológica , Biomassa , Chumbo/farmacocinética , Micorrizas/classificação , Micorrizas/efeitos dos fármacos , Fósforo/metabolismo , Robinia/efeitos dos fármacos , Robinia/metabolismo , Robinia/microbiologia , Zinco/farmacocinética
6.
Sci Total Environ ; 723: 138079, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32222506

RESUMO

There are a large number of abandoned mining areas in China, where external-soil spray seeding is a common technique used to assist with the restoration of these areas. However, the soil component of external-soil spray seeding is deficient, and they are prone to collapse, which complicates ecological restoration. In this study, we added a mineral-solubilizing microbial strain to an external-soil spray seeding substrate in Robinia pseudoacacia and Lespedeza bicolor pots, which were monitored from December 2018 to November 2019. We investigated their root growth and root tensile properties, as well as root-reinforced soil shear strength. The results revealed that the addition of the microbial strain in the substrate improved root growth of Robinia pseudoacacia. The root-reinforced soil shear strength, tensile force and strength were also strengthened by the added microbial strain. Although the growth rate of Robinia pseudoacacia was faster than that of Lespedeza bicolor, the shear strength of the root-reinforced Robinia pseudoacacia soil was lower than that of the Lespedeza bicolor root-reinforced soil of the same diameter. Finally, compared with the cohesion, the change in the friction angle is relatively small, and differences in cohesion resulted in shear strength changes under the same treatment. Our results suggested that the addition of a mineral-solubilizing microbial strain to the external-soil spray seeding substrate could help plants strengthen the soil and positively enhance its effects. These results might also enrich the existing data on the effects of mineral-solubilizing microbial strains on plant roots, while guiding further studies toward improving the efficacy of external-soil spray seeding technologies.


Assuntos
Robinia , Solo , China , Minerais , Raízes de Plantas , Microbiologia do Solo
7.
Sci Total Environ ; 703: 135613, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-31761359

RESUMO

As the driver of plantation ecosystem function, microorganisms can decompose plant residues and soil organic matter. To identify dynamics of microbial communities in litter and soil and its influence by vegetation and soil at regional scales, the plantations of Robinia pseudoacacia at different successional stages (13, 19, 29, and 44 y) was selected on the Loess Plateau. High-throughput sequencing of the 16S rRNA gene was used to examine bacterial communities in litter and soil, and changes in vegetation, litter, and soil characteristics were analyzed. With increase of stand age, coverage and biomass of understory vegetation increased significantly and peaked at 44-y. Concentrations of carbon (C), nitrogen (N), and phosphorus (P) in litter and soil increased significantly, whereas pH values decreased significantly. Composition and diversity of bacterial communities in litter and soil were significantly different. Diversity and richness of litter bacterial communities were higher than that of soils. Relative abundances of Actinobacteria and Proteobacteria in litter were higher than that in soil; relative abundance of Acidobacteria exhibited the reverse trend. The diversity and richness index of vegetation significantly affected that of litter bacterial communities. Soil C/P significantly affected the Simpson and Shannon index of soil bacterial communities. The C/P and pH of litter and soil were significantly correlated with bacterial composition, primarily including Actinobacteria, Acidobacteria, and Gemmatimonadetes. Diversity of litter bacterial communities was more sensitive to the diversity and richness of vegetation flora than that of soil in the succession of R. pseudoacacia. Canopy density, vegetation, and litter and soil nutrients might directly or indirectly affect bacterial communities. Carbon, phosphorus, and pH may be critical factors influencing the composition of bacterial communities in litter and soil.


Assuntos
Robinia/metabolismo , Microbiologia do Solo , Bactérias , Biomassa , Carbono , Florestas , Nitrogênio , Fósforo , Solo/química
8.
Sci Total Environ ; 704: 135243, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31787305

RESUMO

Overexploitation of iron mining in China has caused serious environmental pollution. Therefore, establishing a stable ecological restoration with vegetation in mining areas has gradually aroused people's awareness and obtained extensive concerns. This study aimed to evaluate vegetation restoration with Robinia pseudoacacia (RP), Acer mono (AM) and Pinus koraiensis (PK) in iron mining compared with unrestored area, to investigate the soil environment factors and microbial communities, and to better understand the correlations between soil environment factors and soil microbial communities. Vegetation restoration could reduce soil pH and alleviate soil alkaline, and remarkably increase soil nutrients, especially in RP site. Analysis of 16S rRNA and ITS rRNA gene sequences provided a total of 645,004 and 906, 276 valid sequences clustered into 7091 OTUs and 1689 OTUs at a 0.03 genetic distance for bacteria and fungi, respectively. The predominant bacterial and fungal phyla were Actinobacteria and Ascomycota in studied sites, respectively. Additionally, revegetation significantly increased the relative abundances of Proteobacteria, Gemmatimonadetes, Bacteroidetes and Patescibacteria, and decreased the relative abundance of Actinobacteria. Robinia pseudoacacia harbored the highest soil fungal community diversity, and bacterial Simpson index and Shannon index. Vegetation restoration with RP could clearly shifted soil communities compared to AM and PK. Along with the restoration of vegetation, the remarkable abiotic changes were the accumulation of total C, total N, total P, available P, available N and available K and the decreasing of soil pH, which were the most important factors affecting soil microbial communities. Our results addressed that Robinia pseudoacacia was the best preferable species than AM and PK in improving soil nutrients, soil community diversity and structure in Fe mining, providing a helpful guideline for selection of tree species.


Assuntos
Monitoramento Ambiental , Recuperação e Remediação Ambiental , Microbiota , Microbiologia do Solo , Bactérias , China , Florestas , Fungos , Ferro , Mineração , Pinus , Proteobactérias , Robinia , Solo/química , Árvores
9.
Sci Total Environ ; 707: 134857, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31881519

RESUMO

Knowledge of the species composition of invaded vegetation helps to evaluate an ecological impact of aliens and design an optimal management strategy. We link a new vegetation analysis of a large dataset to the invasion history, ecology and management of Robinia pseudoacacia stands across Southern Europe and provide a map illustrating Robinia distribution. Finally, we compare detected relationships with Central Europe. We show that regional differences in Robinia invasion, distribution, habitats and management are driven both by local natural conditions (climate and soil properties, low competitive ability with native trees) and socioeconomic factors (traditional land-use). Based on the classification of 467 phytosociological relevés we distinguished five broad vegetation types reflecting an oceanity-continentality gradient. The stands were heterogeneous and included 824 taxa, with only 5.8% occurring in more than 10% of samples, representing mainly hemerobic generalists of mesophilous, nutrient-rich and semi-shady habitats. The most common were dry ruderal stands invading human-made habitats. Among native communities, disturbed mesic and alluvial forests were often invaded throughout the area, while dry forests and scrub dominated in Balkan countries. Continuous, long-term and large-scale cultivation represent a crucial factor driving Robinia invasions in natural habitats. Its invasion should be mitigated by suitable management taking into account adjacent habitats and changing cultivation practices to select for native species. Robinia invasion has a comparable pattern in Central and Southern Europe, but there is a substantial difference in management and utilization causing heterogeneity of many South-European stands.


Assuntos
Robinia , Europa (Continente) , Florestas , Árvores
10.
Ying Yong Sheng Tai Xue Bao ; 30(11): 3646-3652, 2019 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-31833676

RESUMO

We explored the distribution characteristics and influencing factors of understory species in Robinia pseudoacacia plantation in Wuqi, Ansai, Mizhi, Yichuan and other places, in combination with niche breadth, soil, altitude and other environmental factors. We analyzed the response mechanism of species distribution to environmental factor to provide a scientific basis for the mana-gement of R. pseudoacacia plantation in loess hilly region. The results showed that the broadly distributed understory species in R. pseudoacacia plantation were Setaria viridis, Heteropappus altaicus, Artemisia scoparia, Poa sphondylodes, Artemisia leucophylla, Ixeris sonchifolia, and Incarvillea sinensis. With the increasing rehabilitationage, the dominant understory species distribution followed the order: Artemisia capillaries → P. sphondylodes → A. scoparia → others (Rubia cordifolia, Rosa rubus and so on) → A. leucophylla → S. viridis. Results from principal component analysis showed that soil total phosphorus (25.6%), altitude (20.3%) and soil total nitrogen (19.3%) were the key factors influencing understory species distribution in R. pseudoacacia plantation. Soil organic carbon content, soil total nitrogen content, soil total phosphorus content, soil water content and the number of understory species distribution in R. pseudoacacia plantation were generally positively correlated with the degree of correlation varying across different species. There was no correlation between the slope aspect and the understory species distribution in R. pseudoacacia plantation. In conclusion, topography and soil factors played important roles in driving understory species distribution. The steeper the slope, the higher the altitude, the fewer understory species in R. pseudoacacia plantation. Understory species distribution was mainly affected by soil total phosphorus content and altitude. The understory species distribution reflected the differences of soil nutrient status, which had a certain guiding role in the management of R. pseudoacacia plantation.


Assuntos
Robinia , Carbono , China , Nitrogênio , Solo
11.
Huan Jing Ke Xue ; 40(6): 2904-2911, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854685

RESUMO

With the aim of studying the effects of different vegetation zones on soil aggregate stability and its stoichiometric characteristics, the soils under Robinia pseudoacacia plantations located within different vegetation zones on the Loess Plateau were selected as the research object. Indicators including the content, stoichiometry, and stability of different aggregate fractions were analyzed. The results showed that the content of >2 mm and 0.25-2 mm, the mean diameter (EMWD), and the geometric mean diameter (EGMD) of aggregate fractions were in the order of forest zone > forest-steppe zone > grassland zone. However, the stability proxies of aggregate fractions across the three vegetation zones indicated that the content and erodibility (K factor) of 0.053-0.25 mm exhibited an opposite trend. The overall trend of the soil organic carbon and total nitrogen of aggregate fractions among the three vegetation zones was that the forest zone significantly overtopped the forest-steppe zone and grassland zone, while the content of total phosphorus showed no significant differences among the three vegetation zones. Additionally, the content of soil organic carbon and total nitrogen of < 0.053 mm and 0.25-2 mm was the highest among the different fractions in the grassland zone, while that of 0.053-0.25 mm and 0.25-2 mm was the highest in the forest-steppe zone. In contrast, there were no significant differences in the content of organic carbon and total nitrogen in the forest zone among the different aggregate fractions. The total phosphorus content topped in < 0.053 mm fractions in the grassland zone and the forest-steppe zone, while that in the forest zone had no significant differences among the different aggregate fractions. Besides, the C:N ratios of < 0.053 mm and 0.053-0.25 mm in the steppe zone and the forest-steppe zone were higher than that in the forest zone, while that of 0.25-2 mm and >2 mm had insignificant differences among the three vegetation zones. The C:P and N:P ratios of fractions in the forest zone were significantly higher than that in the forest-steppe zone and steppe zone. Overall, the stability and stoichiometry of soil aggregate fractions exhibited relatively significant differences among the three vegetation zones. Additionally, the stability, soil organic carbon, and total nitrogen content of aggregate fractions in the forest zone were generally higher than those in the forest-steppe zone and grassland zone.


Assuntos
Florestas , Robinia , Solo/química , Carbono/análise , China , Nitrogênio/análise , Fósforo/análise
12.
In Vivo ; 33(6): 1901-1910, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31662518

RESUMO

BACKGROUND/AIM: Interleukin (IL)-1ß is a pro-inflammatory cytokine that has recently been established as a stimulator of angiogenesis via regulation of proangiogenic factor expression in the tumor microenvironment. This study aimed to demonstrate the inhibitory effects of Robinia pseudoacacia leaf extract (RP) on IL-1ß-mediated tumor angiogenesis. MATERIALS AND METHODS: Secreted embryonic alkaline phosphatase (SEAP) reporter gene assay, ex vivo and in vitro tube formation assay, western blot, and quantitative PCR were used to analyze the inhibitory effect of RP on IL-1ß-mediated angiogenesis. RESULTS: RP inhibited secretion of SEAP, blocked IL-1ß signaling, and inhibited IL-1ß-mediated angiogenesis in ex vivo and in vitro assays. RP inhibited nuclear translocation of NF-ĸB by suppressing phosphorylation of IL-1ß signaling protein kinases and inhibited mRNA expression of IL-1ß-induced pro-angiogenic factors including VEGFA, FGF2, ICAM1, CXCL8, and IL6. CONCLUSION: RP suppressed IL-1ß-mediated angiogenesis and, thus, could be a promising agent in anticancer therapy.


Assuntos
Interleucina-1beta/metabolismo , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Extratos Vegetais/farmacologia , Folhas de Planta/química , Robinia/química , Animais , Citocinas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neoplasias/metabolismo , Neovascularização Patológica/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
13.
Exp Appl Acarol ; 79(1): 1-19, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31552561

RESUMO

Leaf-dwelling mites often prefer to feed on young leaves and also are more likely to inhabit the abaxial leaf side. The aim of our study was to examine whether leaf age may affect production and distribution of eggs on black locust leaves by females of Aculops allotrichus. The eriophyoids were tested for 2.5 days on 'trimmed' compound leaves (with only two opposite leaflets left), which were maintained in vials filled with water. For the experiments we used leaves of three categories: (1) the 'youngest', in which both halves of the adaxial side of leaflets still adhered to each other (and usually remained folded for the next few hours), (2) 'young' with already unfolded leaflets, and (3) 'mature' with fully expanded leaflets. The tested females laid significantly more eggs on developing leaves than on 'mature' ones, although they deposited the highest number of eggs on the 'young' leaves. The distribution of eggs on adaxial or abaxial leaf sides also depended on leaf age. On the 'youngest' leaves, eriophyoids placed similar numbers of eggs on both sides of a blade. However, the older the leaf, the more willingly females deposited eggs on the abaxial side. Our biochemical and morphometrical analyses of black locust leaves indicated significant changes in the contents of nutrients and phenols within leaf tissue, and in the density of trichomes and thickness of the outer epidermal cell walls, correlated with leaf age. Their possible effects on the production and distribution of eggs on leaves by A. allotrichus are discussed.


Assuntos
Cadeia Alimentar , Ácaros/fisiologia , Oviposição , Robinia , Animais , Feminino , Folhas de Planta
14.
Planta ; 250(6): 1897-1910, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31485773

RESUMO

MAIN CONCLUSION: A homologue of the ribosomal protein L22e, Rpf84, regulates root nodule symbiosis by mediating the infection process of rhizobia and preventing bacteroids from degradation in Robinia pseudoacacia. Ribosomal proteins (RPs) are known to have extraribosomal functions, including developmental regulation and stress responses; however, the effects of RPs on symbiotic nodulation of legumes are still unclear. Ribosomal protein 22 of the large 60S subunit (RPL22), a non-typical RP that is only found in eukaryotes, has been shown to function as a tumour suppressor in animals. Here, a homologue of RPL22, Rpf84, was identified from the leguminous tree R. pseudoacacia. Subcellular localization assays showed that Rpf84 was expressed in the cytoplasm and nucleus. Knockdown of Rpf84 by RNA interference (RNAi) technology impaired the infection process and nodule development. Compared with the control, root and stem length, dry weight and nodule number per plant were drastically decreased in Rpf84-RNAi plants. The numbers of root hair curlings, infection threads and nodule primordia were also significantly reduced. Ultrastructure analyses showed that Rpf84-RNAi nodules contained fewer infected cells with fewer bacteria. In particular, remarkable deformation of bacteroids and fusion of multiple symbiosomes occurred in infected cells. By contrast, overexpression of Rpf84 promoted nodulation, and the overexpression nodules maintained a larger infection/differentiation region and had more infected cells filled with bacteroids than the control at 45 days post inoculation, suggesting a retarded ageing process in nodules. These results indicate for the first time that RP regulates the symbiotic nodulation of legumes and that RPL22 may function in initiating the invasion of rhizobia and preventing bacteroids from degradation in R. pseudoacacia.


Assuntos
Genes de Plantas/genética , Proteínas de Plantas/genética , Nodulação/genética , Subunidades Ribossômicas Maiores/genética , Robinia/genética , Clonagem Molecular , Genes de Plantas/fisiologia , Proteínas de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Subunidades Ribossômicas Maiores/fisiologia , Robinia/crescimento & desenvolvimento , Robinia/fisiologia , Nódulos Radiculares de Plantas/crescimento & desenvolvimento , Nódulos Radiculares de Plantas/metabolismo , Simbiose/genética , Transcriptoma
15.
Biomed Pharmacother ; 118: 109335, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31452513

RESUMO

In this study, we aimed to evaluate the antiviral effect of total flavonoids extracted from Robinia pseudoacacia cv. idaho (RPTF) in vivo and its toxicity on rats with oral gavage. RPTF was prepared by percolation with 70% ethanol for 24 h and its antiviral effect on different kinds of viruses was evaluated in vitro by MTT staining. The long-term toxicity of RPTF on rats was evaluated through the detection of general behavior, body weight, food intake and related organ tissue sections of experimental animals. We found that RPTF produced significantly inhibitory effects on HSV-1 and EV-71 viruses with the therapeutic index TI values 113.8 and 46.2, respectively. Moreover, toxicity evaluation in vivo showed no significantly adverse effects in rats, indicating that RPTF was safe in use. In conclusion, we demonstrated that RPTF, natural compounds in the Chinese traditional medicine, could act as promising and effective antiviral therapeutics with relative safety in use.


Assuntos
Antivirais/farmacologia , Antivirais/toxicidade , Flavonoides/farmacologia , Flavonoides/toxicidade , Robinia/química , Testes de Toxicidade , Animais , Antivirais/isolamento & purificação , Peso Corporal/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Feminino , Flavonoides/isolamento & purificação , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Ratos Wistar
16.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2607-2613, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418184

RESUMO

Using Granier-type thermal dissipation probes (TDP), we measured stem xylem sap flow of the natural dominant species Quercus liaotungensis and a reforestation species Robinia pseudoacacia from July to September in 2016 in the semiarid loess hilly region. Meteorological factors and soil water content were simultaneously monitored during the study period. Using cross-correlation analysis, time lag between diurnal patterns of sap flux density and vapor pressure deficit (VPD) was quantitatively estimated. Differences in the time lag between the two species and possible influence by different diameter classes and soil water contents were analyzed. The results showed that the diurnal courses of sap flux density were similar to those of meteorological factors, with daily peaks ear-lier than VPD. The peak of VPD lagged behind the sap flux densities of Q. liaotungensis and R. pseudoacacia 118.2 min and 39.5 min, respectively. The peak of PAR lagged behind the sap flux density of Q. liaotungensis 12.4 min, but was 68.5 min ahead of that for R. pseudoacacia. Time lag between sap flux density and VPD significantly varied between tree species and was affected by soil water content. Those during higher soil water content period were about 32.2 min and 68.2 min longer than those during the period with lower soil water content for the two species, respectively. There was no correlation between time lag and tree diameter classes. The time lag between VPD and sap flux density for R. pseudoacacia was about 21.4 min longer in smaller diameter trees than in larger trees, which was significantly different under the lower soil water content. Our results suggested that the time lag effect between VPD and sap flux densities in the two species reflected their sensitivities to driving factors of transpiration, and that higher soil water content was favorable to sap flux density reaching its peak early. The lower soil water content might lead to lower sensitivity of the trees to meteorological factors. R. pseudoacacia was more sensitive to changes of soil water content.


Assuntos
Transpiração Vegetal/fisiologia , Quercus/fisiologia , Robinia/fisiologia , China , Solo/química , Árvores , Água/análise
17.
Int J Biol Macromol ; 140: 311-322, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31408656

RESUMO

Lignin streams produced in biorefineries are commonly used to obtain energy. In order to increase the competitiveness of this industry, new lignin valorization routes are necessary, for which a depth characterization of this biological macromolecule is essential. In this context, this study analyzed lignin streams of Robinia pseudoacacia L. generated during organosolv and acid hydrolysis pre-treatments and during the subsequent enzymatic hydrolysis. These lignins included dissolved lignins from pre-treatment liquors and saccharification lignins from pre-treated materials. Chemical composition and structural features were analyzed by analytical standard methods and Fourier Transform Infrared spectroscopy (FTIR), size exclusion chromatography (SEC), 13C solid state nuclear magnetic resonance (13C NMR) and 1H-13C two-dimensional nuclear magnetic resonance (2D NMR); while thermal characterization included thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). In general, all studied lignins contained a predominance of ß-O-4' aryl ether linkages, followed by resinol (ß-ß') and phenylcoumaran (ß-5'), with a predominance of syringyl over guaiacyl and hydroxyphenyl units. Nevertheless, the dissolved lignins revealed a removal of linkages, especially ß-O-4', leading to an enrichment of phenolic groups. Moreover, high thermal stability and good thermoplasticity were characteristics of these lignins. Contrary, the saccharification lignins exhibited a more intact structure, but with an important remaining carbohydrates content.


Assuntos
Lignina/química , Robinia/química , Ácidos , Cromatografia em Gel , Hidrólise , Espectroscopia de Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
18.
J Chem Ecol ; 45(8): 657-666, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31407199

RESUMO

The box tree moth, Cydalima perspectalis, is an invasive pest in Europe causing damage on Buxus species. In this study, we aimed to develop a "bisexual" lure to attract both female and male moths. Based on a previous screening bioassay we tested methyl salicylate, phenylacetaldehyde and eugenol as potential attractants in different combinations. The trapping results showed that both binary and ternary blends attracted male and female moths. Catches with these blends were comparable to catches with the synthetic pheromone. Subsequently we carried out single sensillum recordings, which proved the peripheral detection of the above-mentioned compounds on male and female antennae. To identify synergistic flower volatiles, which can be also attractive and can increase the trap capture, we collected flower headspace volatiles from 12 different flowering plant species. Several components of the floral scents evoked good responses from antennae of both females and males in gas chromatography-electroantennographic detection. The most active components were tentatively identified by gas chromatography coupled mass spectrometry as benzaldehyde, cis-ß-ocimene, (±)-linalool and phenethyl alcohol. These selected compounds in combination did not increase significantly the trap capture compared to the methyl salicylate- phenyacetaldehyde blend. Based on these results we discovered the first attractive blend, which was able to attract both adult male and female C. perspectalis in field conditions. These results will yield a good basis for the optimization and development of a practically usable bisexual lure against this invasive pest.


Assuntos
Comportamento Animal/efeitos dos fármacos , Mariposas/fisiologia , Feromônios/farmacologia , Monoterpenos Acíclicos , Animais , Eugenol/química , Eugenol/farmacologia , Feminino , Flores/química , Flores/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Controle de Insetos , Masculino , Monoterpenos/química , Monoterpenos/farmacologia , Feromônios/análise , Robinia/química , Robinia/metabolismo , Rosa/química , Rosa/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/farmacologia
19.
Sci Total Environ ; 687: 1164-1175, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31412452

RESUMO

Biological homogenization is a process of biodiversity loss driven by the introduction and invasion of widespread species and the extinction of specialized, endemic species. This process has accelerated in recent years due to intensive human activities. We focused our study on large areas of forest vegetation that have not yet been intensively studied. Forest management, especially the planting of alien trees, could play a key role in the homogenization process because alien trees can act as habitat 'transformers' influencing vegetation through creating different environmental conditions. Several types of native forests (hardwood floodplain forests, oak forests, and oak-hornbeam forests) have in many regions been replaced by Robinia pseudoacacia plantations. The huge diversity of native broadleaved deciduous forests in the Pannonian and Carpathian regions, with many local differences and considerable geographical variability, could be exposed to the homogenization process due to the planting of Robinia pseudoacacia. We used 282 paired plots of Robinia pseudoacacia-dominated forests and native forests with a distance of 50-250 m among them under the same environmental conditions to avoid the influence of the variability of local environmental conditions on the forest undergrowth. We found out that the replacement of native forests by plantations of Robinia pseudoacacia plays a crucial role in the homogenization process in forest vegetation by unifying microenvironmental conditions of stands and removing the geographically specified variability of plant communities from previous four classes to single one. The replacement reduced total species pool from 422 to 372 species and supported the occurrence of widespread, generalist plant species in the undergrowth.


Assuntos
Florestas , Robinia/crescimento & desenvolvimento , Biodiversidade , Ecossistema , Europa (Continente) , Agricultura Florestal , Espécies Introduzidas , Plantas , Solo , Árvores
20.
Tree Physiol ; 39(9): 1533-1550, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31274160

RESUMO

Rhizobia and legume plants are famous mutualistic symbiosis partners who provide nitrogen nutrition to the natural environment. Rhizobial type III secretion systems (T3SSs) deliver effectors that manipulate the metabolism of eukaryotic host cells. Mesorhizobium amorphae CCNWGS0123 (GS0123) contains two T3SS gene clusters, T3SS-I and T3SS-II. T3SS-I contains all the basal components for an integrated T3SS, and the expression of T3SS-I genes is up-regulated in the presence of flavonoids. In contrast, T3SS-II lacks the primary extracellular elements of T3SSs, and the expression of T3SS-II genes is down-regulated in the presence of flavonoids. Inoculation tests on Robinia pseudoacacia displayed considerable differences in gene expression patterns and levels among roots inoculated with GS0123 and T3SS-deficient mutant (GS0123ΔrhcN1 (GS0123ΔT1), GS0123ΔrhcN2 (GS0123ΔT2) and GS0123ΔrhcN1ΔrhcN2 (GS0123ΔS)). Compared with the GS0123-inoculated plants, GS0123ΔT1-inoculated roots formed very few infection threads and effective nodules, while GS0123ΔT2-inoculated roots formed a little fewer infection threads and effective nodules with increased numbers of bacteroids enclosed in one symbiosome. Moreover, almost no infection threads or effective nodules were observed in GS0123ΔS-inoculated roots. In addition to evaluations of plant immunity signals, we observed that the coexistence of T3SS-I and T3SS-II promoted infection by suppressing host defense response in the reactive oxygen species defense response pathway. Future studies should focus on identifying rhizobial T3SS effectors and their host target proteins.


Assuntos
Mesorhizobium , Robinia , Simbiose , Sistemas de Secreção Tipo III
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