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1.
Rev Environ Contam Toxicol ; 249: 1-27, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30725190

RESUMO

Metals are major abiotic stressors of many organisms, but their toxicity in plants is not as studied as in microorganisms and animals. Likewise, research in plant responses to metal contamination is sketchy. Candidate genes associated with metal resistance in plants have been recently discovered and characterized. Some mechanisms of plant adaptation to metal stressors have been now decrypted. New knowledge on microbial reaction to metal contamination and the relationship between bacterial, archaeal, and fungal resistance to metals has broadened our understanding of metal homeostasis in living organisms. Recent reviews on metal toxicity and resistance mechanisms focused only on the role of transcriptomics, proteomics, metabolomics, and ionomics. This review is a critical analysis of key findings on physiological and genetic processes in plants and microorganisms in responses to soil metal contaminations.


Assuntos
Adaptação Fisiológica/fisiologia , Ecossistema , Metais/toxicidade , Plantas , Microbiologia do Solo , Poluentes do Solo/toxicidade , Animais , Fungos , Metais Pesados , Solo
2.
Rev Environ Contam Toxicol ; 249: 71-131, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30806802

RESUMO

Environmental contamination due to heavy metals (HMs) is of serious ecotoxicological concern worldwide because of their increasing use at industries. Due to non-biodegradable and persistent nature, HMs cause serious soil/water pollution and severe health hazards in living beings upon exposure. HMs can be genotoxic, carcinogenic, mutagenic, and teratogenic in nature even at low concentration. They may also act as endocrine disruptors and induce developmental as well as neurological disorders, and thus, their removal from our natural environment is crucial for the rehabilitation of contaminated sites. To cope with HM pollution, phytoremediation has emerged as a low-cost and eco-sustainable solution to conventional physicochemical cleanup methods that require high capital investment and labor alter soil properties and disturb soil microflora. Phytoremediation is a green technology wherein plants and associated microbes are used to remediate HM-contaminated sites to safeguard the environment and protect public health. Hence, in view of the above, the present paper aims to examine the feasibility of phytoremediation as a sustainable remediation technology for the management of metal-contaminated sites. Therefore, this paper provides an in-depth review on both the conventional and novel phytoremediation approaches; evaluates their efficacy to remove toxic metals from our natural environment; explores current scientific progresses, field experiences, and sustainability issues; and revises world over trends in phytoremediation research for its wider recognition and public acceptance as a sustainable remediation technology for the management of contaminated sites in the twenty-first century.


Assuntos
Biodegradação Ambiental , Metais Pesados , Poluentes do Solo , Plantas , Solo
3.
Rev Environ Contam Toxicol ; 249: 153-197, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30900073

RESUMO

Lead (Pb) is an extremely toxic metal for all living forms including plants. It enters plants through roots from soil or soil solution. It is considered as one of the most eminent examples of anthropogenic environmental pollutant added in environment through mining and smelting of lead ores, coal burning, waste from battery industries, leaded paints, metal plating, and automobile exhaust. Uptake of Pb in plants is a nonselective process and is driven by H+/ATPases. Translocation of Pb metal ions occurs by apoplastic movement resulting in deposition of metal ions in the endodermis and is further transported by symplastic movement. Plants exposed to high concentration of Pb show toxic symptoms due to the overproduction of reactive oxygen species (ROS) through Fenton-Haber-Weiss reaction. ROS include superoxide anion, hydroxyl radical, and hydrogen peroxide, which reach to macro- and micro-cellular levels in the plant cells and cause oxidative damage. Plant growth and plethora of biochemical and physiological attributes including plant growth, water status, photosynthetic efficiency, antioxidative defense system, phenolic compounds, metal chelators, osmolytes, and redox status are adversely influenced by Pb toxicity. Plants respond to toxic levels of Pb in varied ways such as restricted uptake of metal, chelation of metal ions to the root endodermis, enhancement in activity of antioxidative defense, alteration in metal transporters expression, and involvement of plant growth regulators.


Assuntos
Chumbo/toxicidade , Fenômenos Fisiológicos Vegetais , Plantas/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes , Espécies Reativas de Oxigênio
4.
Water Res ; 168: 115153, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655441

RESUMO

A suite of biomarkers, including amino acids, pigments, and lignin phenols coupled with high resolution mass spectrometry were used to evaluate differences in the sources and fate of organic matter (OM) in Everglades treatment wetlands as a model for OM cycling in shallow water wetlands. Five components of the system (water column particulate matter, vertical traps, flocculent material, periphyton, and surface soil) were assessed for OM transformations down-profile (i.e. water column to soil) and between treatment cells dominated by emergent aquatic vegetation (EAV) and submerged aquatic vegetation (SAV), with comparisons to reference sites within the remnant Everglades. We found that OM cycling is fundamentally different between EAV and SAV wetlands, and that SAV wetlands have some shared characteristics with similar habitats in the remnant Everglades. Other than locations densely populated by Typha spp., water column particulate organic C was predominantly derived from microbial/cryptomonad sources, rather than macroscopic sources (vascular plants and algal mats). Bacterial amino acid biomarkers were positively correlated with amino acid degradation indices and organic P (Po), respectively suggesting that microbial abundance is associated with less degraded OM, and that further investigation into relationships between microbial biomass and Po is warranted. Overall, this multi-biomarker approach can elucidate the relative degradation of OM pools, identify sources of OM, and highlight the importance of water column processes in shallow water wetlands.


Assuntos
Purificação da Água , Áreas Alagadas , Biomarcadores , Plantas , Solo
5.
Oecologia ; 191(4): 1015-1024, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31667602

RESUMO

Plant species can be characterized by different growth strategies related to their inherent growth and recovery rates, which shape their responses to stress and disturbance. Ecosystem engineering, however, offers an alternative way to cope with stress: modifying the environment may reduce stress levels. Using an experimental study on two seagrass species with contrasting traits, the slow-growing Zostera marina vs. the fast-growing Zostera japonica, we explored how growth strategies versus ecosystem engineering may affect their resistance to stress (i.e. addition of organic material) and recovery from disturbance (i.e. removal of above-ground biomass). Ecosystem engineering was assessed by measuring sulphide levels in the sediment porewater, as seagrass plants can keep sulphide levels low by aerating the rhizosphere. Consistent with predictions, we observed that the fast-growing species had a high capacity to recover from disturbance. It was also more resistant to stress and still able to maintain high standing stock with increasing stress levels because of its ecosystem engineering capacity. The slow-growing species was not able to maintain its standing stock under stress, which we ascribe to a weak capacity for ecosystem engineering regarding this particular stress. Overall, our study suggests that the combination of low-cost investment in tissues with ecosystem engineering to alleviate stress creates a new path in the growth trade-off between investment in strong tissues or fast growth. It does so by being both fast in recovery and more resistant. As such low-cost ecosystem engineering may occur in more species, we argue that it should be considered in assessing plant resilience.


Assuntos
Ecossistema , Zosteraceae , Biomassa , Plantas
6.
Oecologia ; 191(4): 873-886, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31676969

RESUMO

An animal's diet contributes to its survival and reproduction. Variation in diet can alter the structure of community-level consumer-resource networks, with implications for ecological function. However, much remains unknown about the underlying drivers of diet breadth. Here we use a network approach to understand how consumer diet changes in response to local and landscape context and how these patterns compare between closely-related consumer species. We conducted field surveys to build 36 quantitative plant-pollinator networks using observation-based and pollen-based records of visitation across the gulf-coast cotton growing region of Texas, US. We focused on two key cotton pollinator species in the region: the social European honey bee, Apis mellifera, and the solitary native long-horned bee, Melissodes tepaneca. We demonstrate that diet breadth is highly context-dependent. Specifically, local factors better explain patterns of diet than regional factors for both species, but A. mellifera and M. tepaneca respond to local factors with contrasting patterns. Despite being collected directly from cotton blooms, both species exhibit significant preferences for non-cotton pollen, indicating a propensity to spend substantial effort foraging on remnant vegetation despite the rarity of these patches in the intensely managed cotton agroecosystem. Overall, our results demonstrate that diet is highly context- and species-dependent and thus an understanding of both factors is key for evaluating the conservation of important cotton pollinators.


Assuntos
Pólen , Polinização , Animais , Abelhas , Dieta , Plantas , Texas
7.
Zootaxa ; 4652(1): zootaxa.4652.1.10, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31716890

RESUMO

The genus Rubrocuneocoris Schuh is recognized from Vietnam for the first time, with a new species, R. vietnamensis n. sp.  The new species is described and documented with images of the habitus and male genitalic structures. Male and female genitalic structures are described for R. albescens Yasunaga. Species of Rubrocuneocoris described from Taiwan are herein transferred to Atractotomoidea Yasunaga and the following new combinations are accordingly proposed: Atractotomoidea falcis (Lin 2006) n. comb., A. maculosus (Lin 2006) n. comb., A. nodus (Lin 2006) n. comb., and A. trifidus (Lin 2006) n. comb. A revised checklist of Rubrocuneocoris is presented.


Assuntos
Heterópteros , Distribuição Animal , Animais , Feminino , Masculino , Plantas , Taiwan , Vietnã
8.
Science ; 366(6467): 805-806, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31727820
9.
Zootaxa ; 4614(3): zootaxa.4614.3.5, 2019 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-31716369

RESUMO

Six valid species of Pseudodineura are now recognised as occurring in the West Palaearctic, and the only described species of the related genus Endophytus. Larvae of all species are leaf-miners in Ranunculaceae. An identification key to adults is provided, followed by species commentaries which include summarised data on taxonomy, larval host plants, and distribution, with particular reference to Sweden. Whereas identification of some specimens using morphological characters may not be possible, each species apparently has a distinct COI barcode sequence. Pseudodineura heringi (Enslin, 1921) is a new junior synonym of P. parvula (Klug, 1816). Pseudodineura mocsaryi Zombori, 1976 and P. scaligera Zombori, 1979 are new junior synonyms of P. clematidisrectae Hering, 1935. Lectotypes are designated for: Dolerus minutus Hartig, 1837, Pelmatopus clematidis Hering, 1932, P. enslini Hering, 1923, P. heringi Enslin, 1921, and P. mentiens var. konowi Enslin, 1921.


Assuntos
Himenópteros , Animais , Larva , Plantas , Suécia
10.
Zootaxa ; 4668(1): zootaxa.4668.1.1, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31716636

RESUMO

Taxonomy of the Texas representatives of the genus Xanthonia Baly, 1863 (Coleoptera: Chrysomelidae: Eumolpinae) is reviewed. A total of 12 species are recognized in Texas, including seven that are described as new: X. hirsuta Weisman, X. marquai Riley Quinn, X. nitida Weisman, X. parva Riley Quinn, X. picturata Weisman Riley, X. querci Weisman, and X. texana Weisman. A key to the species recorded from Texas is given together with habitus and male genitalia figures, plant associations, and Texas range maps. Adult seasonality and plant preference data are graphically presented for abundant central Texas species. Previous Texas records of X. striata Staines Weisman are based on misidentifications of X. angulata Staines Weisman.


Assuntos
Besouros , Animais , Genitália Masculina , Masculino , Plantas , Texas
11.
Zootaxa ; 4691(2): zootaxa.4691.2.10, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31719409

RESUMO

Because the generic name Elliotia proposed by us (Stiles et al. 2017a) was found to be preoccupied, we herein rename this genus, including a detailed diagnosis; the generic circumscription and type species remain unchanged. This change does not affect the generic reorganization of the Trochilini presented by Stiles et al. (2017a).


Assuntos
Plantas
12.
Zootaxa ; 4686(2): zootaxa.4686.2.3, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31719488

RESUMO

The genus Meganola Dyar, 1898 is reviewed for Korea, with 12 species, including the new species, Meganola parki Oh Cha, sp. n. Illustrations of adults and genitalia of all the Korean species are provided, with a key to species of Meganola based on the external morphology and male genitalia. All known host plants are provided, some of them newly recorded.


Assuntos
Lepidópteros , Mariposas , Animais , Genitália , Masculino , Plantas , República da Coreia
13.
Science ; 366(6465): 568-569, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31672879
14.
J Environ Qual ; 48(5): 1300-1313, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31589737

RESUMO

The development of highly concentrated phosphorus (P) fertilizers, such as triple superphosphate, by the Tennessee Valley Authority helped mark the beginning of a revolution in the way we manage food crop nutrition. Since then, scientists, with the help of farmers, have made great advancements in the understanding of P fate and transport across many environments but largely have failed to produce a new generation of products and/or application techniques that are widely accepted and that vastly improve plant acquisition efficiency. Under certain conditions, important advancements have been made. For example, applying liquid formulations of phosphates in lieu of dry granules in some highly calcareous soils has dramatically reduced precipitation as sparingly soluble calcium phosphate minerals, but other attempts, such as the co-application of humic substances, sorption to layered double hydroxides, or use of nanoparticles, have not generated the kind of results necessary to continue economically increasing crop yields without further environmental cost. New sources of fertility will need to be affordable to produce, transport, and furnish P to soil solution in a manner well synchronized with crop demand. This paper provides a review of recent literature on cutting-edge phosphorus fertilizer technology. The goal is that this synthesis will be used as a starting point from which a larger discussion on responsible nutrient management and increased P use efficiency research can be built.


Assuntos
Fertilizantes , Fósforo , Fosfatos , Plantas , Solo
15.
Anal Bioanal Chem ; 411(27): 7281-7291, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31608426

RESUMO

The composition of Atlantic salmon feed has changed considerably over the last two decades from being marine-based (fishmeal and fish oil) to mainly containing plant ingredients. Consequently, concern related to traditional persistent contaminants typically associated with fish-based feed has been replaced by other potential contaminants not previously associated with salmon farming. This is the case for many pesticides, which are used worldwide to increase food production, and may be present in plant ingredients. Earlier studies have identified two organophosphorus pesticides, chlorpyrifos-methyl and pirimiphos-methyl, in plant ingredients used for aquafeed production. In the present study, we developed a reliable and sensitive analytical method, based on liquid chromatography coupled to tandem mass spectrometry, for the determination of these pesticides and their main metabolites in warm water (zebrafish) and cold water (Atlantic salmon) species, where possible differences in metabolites could be expected. The method was tested in whole zebrafish and in different salmon tissues, such as muscle, bile, kidney, fat, and liver. The final objective of this work was to assess kinetics of chlorpyrifos-methyl and pirimiphos-methyl and their main metabolites in fish tissue, in order to fill the knowledge gaps on these metabolites in fish tissues when fed over prolonged time.


Assuntos
Ração Animal/análise , Clorpirifos/análogos & derivados , Compostos Organotiofosforados/análise , Praguicidas/análise , Salmão/metabolismo , Peixe-Zebra/metabolismo , Animais , Clorpirifos/análise , Clorpirifos/metabolismo , Cromatografia Líquida de Alta Pressão , Pesqueiros , Limite de Detecção , Compostos Organotiofosforados/metabolismo , Praguicidas/metabolismo , Plantas/química , Alimentos Marinhos/análise , Espectrometria de Massas em Tandem
16.
Plant Dis ; 103(12): 3101-3107, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31613192

RESUMO

Phytophthora cinnamomi is an ecologically and agriculturally significant plant pathogen. Early and accurate detection of P. cinnamomi is paramount to disease prevention and management. In this study, a loop-mediated isothermal amplification (LAMP) assay utilizing a new target gene Pcinn100006 identified from genomic sequence data was developed and evaluated for the detection of P. cinnamomi. This Pcinn100006 LAMP assay was found highly specific to P. cinnamomi. All 10 tested isolates of P. cinnamomi yielded positive results, whereas 50 isolates belonging to 16 other Phytophthora species, Globisporangium ultimum, and 14 fungal species lacked detection. This assay was 10 times more sensitive (100 pg in a 25-µl reaction mixture) than a conventional PCR assay (2 ng in a 50-µl reaction mixture) for detecting the genomic DNA of P. cinnamomi. In addition, it detected P. cinnamomi from artificially inoculated leaves of Cedrus deodara. Moreover, detection rates of P. cinnamomi using environmental DNAs extracted from 13 naturally infested rhizosphere samples were 100% in the Pcinn100006 LAMP assay versus 46% in the conventional PCR assay. Considering its higher accuracy and shorter time span, this Pcinn100006 LAMP assay is a promising diagnostic tool to replace conventional PCR-based and culture-dependent assays for screening of P. cinnamomi in regions at risk of infection or contamination.


Assuntos
Agricultura , Genoma de Protozoário , Técnicas de Amplificação de Ácido Nucleico , Phytophthora , Agricultura/métodos , Phytophthora/genética , Doenças das Plantas/parasitologia , Plantas , Rizosfera , Sensibilidade e Especificidade
17.
Oecologia ; 191(3): 493-504, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31571041

RESUMO

Climate change is causing species with non-overlapping ranges to come in contact, and a key challenge is to predict the consequences of such species re-shuffling. Experiments on plants have focused largely on novel competitive interactions; other species interactions, such as plant-microbe symbioses, while less studied, may also influence plant responses to climate change. In this greenhouse study, we evaluated interactions between soil microbes and alpine-restricted plant species, simulating a warming scenario in which low-elevation microbes migrate upslope into the distribution of alpine plants. We examined three alpine grasses from the Rocky Mountains, CO, USA (Poa alpina, Festuca brachyphylla, and Elymus scribneri). We used soil inocula from within (resident) or below (novel) the plants' current elevation range and examined responses in plant biomass, plant traits, and fungal colonization of roots. Resident soil inocula from the species' home range decreased biomass to a greater extent than novel soil inocula. The depressed growth in resident soils suggested that these soils harbor more carbon-demanding microbes, as plant biomass generally declined with greater fungal colonization of roots, especially in resident soil inocula. Although plant traits did not respond to the provenance of soil inocula, specific leaf area declined and root:shoot ratio increased when soil inocula were sterilized, indicating microbial mediation of plant trait expression. Contrary to current predictions, our findings suggest that if upwardly migrating microbes were to displace current soil microbes, alpine plants may benefit from this warming-induced microbial re-shuffling.


Assuntos
Microbiologia do Solo , Solo , Biomassa , Carbono , Plantas
18.
J Environ Manage ; 252: 109644, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605911

RESUMO

The National Seed Strategy for Rehabilitation and Restoration aims to increase the use of native seeds in rehabilitation and restoration projects. This requires the development of a native seed supply industry. This paper examines the challenge of developing native seed supply for Bureau of Land Management (BLM) land holdings in the Colorado Plateau, USA. On the demand side of the market, native seed requirements are linked to events that trigger the need for restoration, such as wildfires, which are highly variable. The variability of demand is moderated somewhat by fire management and seed acquisition policies, but remains high. Acquisitions of native seeds are typically smaller in quantity and more variable than acquisitions of non-native seeds. Prices of native seeds are typically higher and more variable than prices of non-native seeds, while the price elasticity of demand for native seeds is typically lower than for non-native seeds. The variability of demand for native seeds has discouraged development of a native seed supply industry. We find that adoption of policies to stabilize demand, supported by contracts with growers, could help to encourage the emergence of a strong field-grown native seed sector in the Colorado Plateau.


Assuntos
Conservação dos Recursos Naturais , Sementes , Colorado , Plantas
19.
Postepy Biochem ; 65(2): 109-117, 2019 06 06.
Artigo em Polonês | MEDLINE | ID: mdl-31642649

RESUMO

Cytokinins are a group of plant hormones which play an important role in plant growth and development. They produce various effects when applied to intact plants. They particularly stimulate protein synthesis and participate in cell cycle control. First discovered cytokinin was N6-furfuryladenine (kinetin). It is a strong inhibitor of proteins and nucleic acids oxidation in vitro and in vivo. Both kinetin and its ribosides (N6-furfuryladenosine, kinetin riboside) as natural compounds occur in the milk of coconuts on the nanomole level. Kinetin riboside selectively inhibits the proliferation of cancer cells and induce their apoptosis. This review focuses on the kinetin riboside occurrence, and primarily on its metabolism, and biological activity.


Assuntos
Cinetina/metabolismo , Cinetina/farmacologia , Reguladores de Crescimento de Planta/metabolismo , Reguladores de Crescimento de Planta/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Plantas/efeitos dos fármacos
20.
Sci Total Environ ; 693: 133647, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31635014

RESUMO

Boreal wetlands are at risk of degradation from anthropogenic activities including oil sands energy extraction. Despite efforts to monitor the impacts of oil sands energy extraction-related activities on wetland ecology, few studies examine the impacts of diverse human development types on wetland plant communities. Here, we sought to quantify the effects of human development in the Athabasca, Peace River, and Cold Lake Oil Sands Regions in Alberta, Canada, and to examine its impact on wetland plant community composition. Across the region, we found that total development and development related to energy and mining were both low; ~80% of the study area was undeveloped. Despite the low spatial extent, total anthropogenic development was negatively correlated with site-level conservatism (a metric of plant tolerance to environmental perturbation) in all five wetland classes examined. This suggests that wetlands surrounded by human development are inhabited by generalist species that are tolerant of environmental disturbance. Moreover, distinct floristic groups within each wetland class could be distinguished based on their total developed area, providing additional evidence that human development affects plant composition and diversity, despite its limited extent in the study area. In contrast to total development, energy and mining development had an inconsistent or no detectable impact on wetland plant community composition at the regional level, likely because although oils sands surface mining is intensive, it is spatially restricted to a small area within the oil sands region. Our findings show that wetland plant communities in the oil sands region are impacted by multiple types of human land use concurrently; further research should aim to evaluate both the distinct impacts of different land use types using gradients of development intensity, as well as the cumulative impacts of multiple land use types happening concurrently.


Assuntos
Monitoramento Ambiental , Campos de Petróleo e Gás , Plantas , Poluentes Químicos da Água/análise , Áreas Alagadas , Alberta , Humanos , Mineração
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