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Helene Frerot - One of the best experts on this subject based on the ideXlab platform.
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Evolutionary dynamics of quantitative variation in an adaptive trait at the regional scale: The case of zinc Hyperaccumulation in Arabidopsis halleri.
Molecular ecology, 2018Co-Authors: Alicja Babst-kostecka, Henk Schat, Pierre Saumitou-laprade, Krystyna Grodzińska, Angélique Bourceaux, Maxime Pauwels, Helene FrerotAbstract:Metal Hyperaccumulation in plants is an ecological trait whose biological significance remains debated, in particular because the selective pressures that govern its evolutionary dynamics are complex. One of the possible causes of quantitative variation in Hyperaccumulation may be local adaptation to metalliferous soils. Here, we explored the population genetic structure of Arabidopsis halleri at fourteen metalliferous and nonmetalliferous sampling sites in southern Poland. The results were integrated with a quantitative assessment of variation in zinc Hyperaccumulation to trace local adaptation. We identified a clear hierarchical structure with two distinct genetic groups at the upper level of clustering. Interestingly, these groups corresponded to different geographic subregions, rather than to ecological types (i.e., metallicolous vs. nonmetallicolous). Also, approximate Bayesian computation analyses suggested that the current distribution of A. halleri in southern Poland could be relictual as a result of habitat fragmentation caused by climatic shifts during the Holocene, rather than due to recent colonization of industrially polluted sites. In addition, we find evidence that some nonmetallicolous lowland populations may have actually derived from metallicolous populations. Meanwhile, the distribution of quantitative variation in zinc Hyperaccumulation did separate metallicolous and nonmetallicolous accessions, indicating more recent adaptive evolution and diversifying selection between metalliferous and nonmetalliferous habitats. This suggests that zinc Hyperaccumulation evolves both ways-towards higher levels at nonmetalliferous sites and lower levels at metalliferous sites. Our results open a new perspective on possible evolutionary relationships between A. halleri edaphic types that may inspire future genetic studies of quantitative variation in metal Hyperaccumulation.
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Habitat heterogeneity in the pseudometallophyte Arabidopsis halleri and its structuring effect on natural variation of zinc and cadmium Hyperaccumulation
Plant and Soil, 2017Co-Authors: Helene Frerot, Pierre Saumitou-laprade, Nina-coralie Hautekèete, Isabelle Decombeix, Marie-hélène Bouchet, Anne Créach, Yves Piquot, Maxime PauwelsAbstract:Arabidopsis halleri is a pseudometallophyte plant model hyperaccumulating zinc and cadmium. This study investigates which abiotic parameters may cause phenotypic divergence among accessions for Hyperaccumulation traits. We studied 23 sites from a mining and industrial area in Italian Alps. Sites were characterized for altitude, topographic data, absolute humidity, and accompanying flora. Plant-soil couples were also sampled to measure shoot metal concentrations and soil elemental concentrations, particles size distribution, and pH. Using PLSR analyses, we investigated whether the natural variation in Hyperaccumulation abilities could be explained by variation of abiotic parameters. Habitats heterogeneity was high, distinguishing metalliferous and non-metalliferous sites. However, heterogeneity was also observed for soil metal concentrations, particles size distribution and altitude, particularly among metalliferous habitats. This result was supported by floristic data. Soil zinc and cadmium concentrations showed the most contrasting effects on phenotypic divergence between metalliferous and non-metalliferous habitats. However, except for cadmium-related traits in non-metalliferous habitats, other abiotic parameters may affect the variation of zinc or cadmium Hyperaccumulation within each habitat type. The classical dichotomous distinction between metalliferous and non-metalliferous habitats may hide the ecological diversity existing within each category for abiotic parameters. This study reveals abiotic parameters that may shape the natural variation of Hyperaccumulation abilities.
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genetic architecture of zinc Hyperaccumulation in arabidopsis halleri the essential role of qtl environment interactions
New Phytologist, 2010Co-Authors: Helene Frerot, Nathalie Verbruggen, Michel-pierre Faucon, G. Willems, C. Godé, A. Courseaux, A. Darracq, Pierre SaumitoulapradeAbstract:Summary •This study sought to determine the main genomic regions that control zinc (Zn) Hyperaccumulation in Arabidopsis halleri and to examine genotype × environment effects on phenotypic variance. To do so, quantitative trait loci (QTLs) were mapped using an interspecific A. halleri × Arabidopsis lyrata petraea F2 population. •The F2 progeny as well as representatives of the parental populations were cultivated on soils at two different Zn concentrations. A linkage map was constructed using 70 markers. •In both low and high pollution treatments, zinc Hyperaccumulation showed high broad-sense heritability (81.9 and 74.7%, respectively). Five significant QTLs were detected: two QTLs specific to the low pollution treatment (chromosomes 1 and 4), and three QTLs identified at both treatments (chromosomes 3, 6 and 7). These QTLs explained 50.1 and 36.5% of the phenotypic variance in low and high pollution treatments, respectively. Two QTLs identified at both treatments (chromosomes 3 and 6) showed significant QTL × environment interactions. •The QTL on chromosome 3 largely colocalized with a major QTL previously identified for Zn and cadmium (Cd) tolerance. This suggests that Zn tolerance and Hyperaccumulation share, at least partially, a common genetic basis and may have simultaneously evolved on heavy metal-contaminated soils.
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Zinc tolerance and Hyperaccumulation in F-1 and F-2 offspring from intra and interecotype crosses of Thlaspi caerulescens
New Phytologist, 2005Co-Authors: Helene Frerot, C Lefebvre, Christian Collin, Christophe Petit, A. Dos Santos, Josep EscarreAbstract:The relationship between zinc (Zn) tolerance and Hyperaccumulation in Thlaspi caerulescens was investigated from F-1 and F-2 crosses within and among metallicolous and nonmetallicolous Mediterranean populations. F-1 offspring were grown on increasingly Zn-enriched soils to test Zn enrichment effects, and many families of F-2 offspring were grown on a Zn-rich soil. Tolerance of F-1 offspring depended on stress intensity. Tolerance of interecotype crosses was intermediate between that of the intraecotype crosses. No difference in Zn accumulation appeared among the F-1 offspring from the three crosses involving metallicolous parents. Otherwise, none of these offspring exceeded the Zn Hyperaccumulation threshold (10 000 mg kg(-1)), unlike the nonmetallicolous ones. The latter also showed the highest mortality. In some F-2 families from interecotype crosses, Hyperaccumulation values exceeded 15 000 mg kg(-1) in nontolerant offspring, whereas tolerant offspring displayed lower values (c. 10 000 mg kg(-1)). There was no difference between tolerant and nontolerant offspring when they showed low Hyperaccumulation. Therefore, the relationship between tolerance and Hyperaccumulation in F-1 and F-2 crosses depended on the Hyperaccumulation level of plants.
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zinc tolerance and Hyperaccumulation in f1 and f2 offspring from intra and interecotype crosses of thlaspi caerulescens
New Phytologist, 2004Co-Authors: Helene Frerot, C Lefebvre, Christian Collin, Dos A Santos, Christophe Petit, Josep EscarreAbstract:Summary • The relationship between zinc (Zn) tolerance and Hyperaccumulation in Thlaspi caerulescens was investigated from F1 and F2 crosses within and among metallicolous and nonmetallicolous Mediterranean populations. • F1 offspring were grown on increasingly Zn-enriched soils to test Zn enrichment effects, and many families of F2 offspring were grown on a Zn-rich soil. • Tolerance of F1 offspring depended on stress intensity. Tolerance of interecotype crosses was intermediate between that of the intraecotype crosses. No difference in Zn accumulation appeared among the F1 offspring from the three crosses involving metallicolous parents. Otherwise, none of these offspring exceeded the Zn Hyperaccumulation threshold (10 000 mg kg−1), unlike the nonmetallicolous ones. The latter also showed the highest mortality. In some F2 families from interecotype crosses, Hyperaccumulation values exceeded 15 000 mg kg−1 in nontolerant offspring, whereas tolerant offspring displayed lower values (c. 10 000 mg kg−1). There was no difference between tolerant and nontolerant offspring when they showed low Hyperaccumulation. • Therefore, the relationship between tolerance and Hyperaccumulation in F1 and F2 crosses depended on the Hyperaccumulation level of plants.
David E. Salt - One of the best experts on this subject based on the ideXlab platform.
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reciprocal grafting separates the roles of the root and shoot in zinc Hyperaccumulation in thlaspi caerulescens
New Phytologist, 2009Co-Authors: Marcelo De Almeida Guimaraes, Jean Louis Gustin, David E. SaltAbstract:Summary • The extreme phenotype of zinc (Zn) Hyperaccumulation, which is found in several Brassicaceae species, is determined by mechanisms that promote elevated Zn tolerance and high Zn accumulation in shoots. • We used reciprocal grafting between a Zn hyperaccumulator, Thlaspi caerulescens, and a Zn nonaccumulator, Thlaspi perfoliatum, to determine the relative importance of roots and shoots in Zn Hyperaccumulation and hypertolerance. • Leaves from plants with a T. perfoliatum rootstock and a T. caerulescens shoot scion did not hyperaccumulate Zn, whereas plants with a T. caerulescens rootstock and a T. perfoliatum shoot scion did hyperaccumulate Zn. However, although leaves from plants with a T. caerulescens rootstock and a T. perfoliatum shoot scion hyperaccumulated Zn, at high Zn loads these leaves showed significant symptoms of Zn toxicity, unlike leaves of self grafted T. caerulescens. • Hyperaccumulation of Zn in leaves of the hyperaccumulator T. caerulescens is pri-marily dictated by root processes. Further, the mechanisms controlling Zn hypertolerance in the hyperaccumulator T. caerulescens are driven primarily by shoot processes.
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Genetic and Molecular Dissection of Arsenic Hyperaccumulation in the fern Pteris vittata.
2008Co-Authors: Jo Ann Banks, David E. SaltAbstract:Pteris vittata is a fern that is extraordinary in its ability to tolerate hyperaccumulate high levels of arsenic (As). The goals of the proposed research, to identify the genes that are necessary for As Hyperaccumulation in P. vittata using molecular and genetic approaches and to understand the physiology of arsenic uptake and distribution in the living plant, were accomplished during the funding period. The genes that have been identified may ultimately enable the engineering or selection of other plants capable of As Hyperaccumulation. This is important for the phytoremediation of arsenic-contaminated soils in areas where P. vittata cannot grow.
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Assessment of plants from the Brassicaceae family as genetic models for the study of nickel and zinc Hyperaccumulation
The New phytologist, 2006Co-Authors: Wendy Ann Peer, Roger D Reeves, John L Freeman, Brett Lahner, Mehrzad Mahmoudian, Elizabeth L. Richards, Angus S. Murphy, David E. SaltAbstract:We report on the second phase of a programme to select a relative of Arabidopsis thaliana for use in large-scale molecular genetic studies of nickel (Ni) and zinc (Zn) Hyperaccumulation. We also report on the relatedness among Thlaspi caerulescens accessions and the utility of using O-acetyl-L-serine as a marker for Ni and Zn Hyperaccumulation potential. Twenty-seven new accessions of metal-accumulating species collected in the Czech Republic, France, Greece, Italy, Slovenia and the USA during Spring-Summer 2002 were evaluated. The criteria established for selection were Hyperaccumulation of metals (Ni and Zn); compact growth habit; reasonable time to flowering; production of > or = 1000 seeds per plant; self-fertility; compact diploid genome; high sequence similarity to A. thaliana; > or = 0.1% transformation efficiency with easy selection. We conclude that the best candidate identified in the first phase was the best candidate overall: T. caerulescens accession St Felix de Pallieres.
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constitutively elevated salicylic acid signals glutathione mediated nickel tolerance in thlaspi nickel hyperaccumulators
Plant Physiology, 2005Co-Authors: John L Freeman, Amber Hopf, Daniel Garcia, David E. SaltAbstract:Progress is being made in understanding the biochemical and molecular basis of nickel (Ni)/zinc (Zn) Hyperaccumulation in Thlaspi; however, the molecular signaling pathways that control these mechanisms are not understood. We observed that elevated concentrations of salicylic acid (SA), a molecule known to be involved in signaling induced pathogen defense responses in plants, is a strong predictor of Ni Hyperaccumulation in the six diverse Thlaspi species investigated, including the hyperaccumulators Thlaspi goesingense, Thlaspi rosulare, Thlaspi oxyceras, and Thlaspi caerulescens and the nonaccumulators Thlaspi arvense and Thlaspi perfoliatum. Furthermore, the SA metabolites phenylalanine, cinnamic acid, salicyloyl-glucose, and catechol are also elevated in the hyperaccumulator T. goesingense when compared to the nonaccumulators Arabidopsis (Arabidopsis thaliana) and T. arvense. Elevation of free SA levels in Arabidopsis, both genetically and by exogenous feeding, enhances the specific activity of serine acetyltransferase, leading to elevated glutathione and increased Ni resistance. Such SA-mediated Ni resistance in Arabidopsis phenocopies the glutathione-based Ni tolerance previously observed in Thlaspi, suggesting a biochemical linkage between SA and Ni tolerance in this genus. Intriguingly, the hyperaccumulator T. goesingense also shows enhanced sensitivity to the pathogen powdery mildew (Erysiphe cruciferarum) and fails to induce SA biosynthesis after infection. Nickel Hyperaccumulation reverses this pathogen hypersensitivity, suggesting that the interaction between pathogen resistance and Ni tolerance and Hyperaccumulation may have played a critical role in the evolution of metal Hyperaccumulation in the Thlaspi genus.
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arsenic Hyperaccumulation in gametophytes of pteris vittata a new model system for analysis of arsenic Hyperaccumulation
Plant Physiology, 2004Co-Authors: Luke Gumaelius, David E. Salt, Brett Lahner, Jo Ann BanksAbstract:The sporophyte of the fern Pteris vittata is known to hyperaccumulate arsenic (As) in its fronds to .1% of its dry weight. Hyperaccumulation of As by plants has been identified as a valuable trait for the development of a practical phytoremediation processes for removal of this potentially toxic trace element from the environment. However, because the sporophyte of P. vittata is a slow growing perennial plant, with a large genome and no developed genetics tools, it is not ideal for investigations into the basic mechanisms underlying As Hyperaccumulation in plants. However, like other homosporous ferns, P. vittata produces and releases abundant haploid spores from the parent sporophyte plant which upon germination develop as free-living, autotrophic haploid gametophyte consisting of a small (,1 mm) single-layered sheet of cells. Its small size, rapid growth rate, ease of culture, and haploid genome make the gametophyte a potentially ideal system for the application of both forward and reverse genetics for the study of As Hyperaccumulation. Here we report that gametophytes of P. vittata hyperaccumulate As in a similar manner to that previously observed in the sporophyte. Gametophytes are able to grow normally in medium containing 20 mM arsenate and accumulate .2.5% of their dry weight as As. This contrasts with gametophytes of the related nonaccumulating fern Ceratopteris richardii, which die at even low (0.1 mM) As concentrations. Interestingly, gametophytes of the related As accumulator Pityrogramma calomelanos appear to tolerate and accumulate As to intermediate levels compared to P. vittata and C. richardii. Analysis of gametophyte populations from 40 different P. vittata sporophyte plants collected at different sites in Florida also revealed the existence of natural variability in As tolerance but not accumulation. Such observations should open the door to the application of new and powerful genetic tools for the dissection of the molecular mechanisms involved in As Hyperaccumulation in P. vittata using gametophytes as an easily manipulated model system.
Henk Schat - One of the best experts on this subject based on the ideXlab platform.
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Evolutionary dynamics of quantitative variation in an adaptive trait at the regional scale: The case of zinc Hyperaccumulation in Arabidopsis halleri.
Molecular ecology, 2018Co-Authors: Alicja Babst-kostecka, Henk Schat, Pierre Saumitou-laprade, Krystyna Grodzińska, Angélique Bourceaux, Maxime Pauwels, Helene FrerotAbstract:Metal Hyperaccumulation in plants is an ecological trait whose biological significance remains debated, in particular because the selective pressures that govern its evolutionary dynamics are complex. One of the possible causes of quantitative variation in Hyperaccumulation may be local adaptation to metalliferous soils. Here, we explored the population genetic structure of Arabidopsis halleri at fourteen metalliferous and nonmetalliferous sampling sites in southern Poland. The results were integrated with a quantitative assessment of variation in zinc Hyperaccumulation to trace local adaptation. We identified a clear hierarchical structure with two distinct genetic groups at the upper level of clustering. Interestingly, these groups corresponded to different geographic subregions, rather than to ecological types (i.e., metallicolous vs. nonmetallicolous). Also, approximate Bayesian computation analyses suggested that the current distribution of A. halleri in southern Poland could be relictual as a result of habitat fragmentation caused by climatic shifts during the Holocene, rather than due to recent colonization of industrially polluted sites. In addition, we find evidence that some nonmetallicolous lowland populations may have actually derived from metallicolous populations. Meanwhile, the distribution of quantitative variation in zinc Hyperaccumulation did separate metallicolous and nonmetallicolous accessions, indicating more recent adaptive evolution and diversifying selection between metalliferous and nonmetalliferous habitats. This suggests that zinc Hyperaccumulation evolves both ways-towards higher levels at nonmetalliferous sites and lower levels at metalliferous sites. Our results open a new perspective on possible evolutionary relationships between A. halleri edaphic types that may inspire future genetic studies of quantitative variation in metal Hyperaccumulation.
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Hyperaccumulation of thallium is population-specific and uncorrelated with caesium accumulation in the thallium hyperaccumulator, Biscutella laevigata
Plant and Soil, 2012Co-Authors: Filip Pošćić, Luca Marchiol, Henk SchatAbstract:Aims Thallium Hyperaccumulation has previously been observed in the field but there are no laboratory confirmations for Biscutella laevigata. Tolerance and accumulation of thallium and its chemical analogue caesium were compared in one non-metallicolous and three metallicolous (calamine) populations of the candidate Tl hyperaccumulator species, B. laevigata. Methods Tolerance and accumulation were evaluated in hydroponics. Moreover, Tl and Cs accumulation were measured at different K concentrations in the nutrient solution. Seedlings were also grown in Tl contaminated calamine soil. Results Estimated from their root growth response, all the calamine populations showed hypertolerance to Tl, although to very different degrees. Foliar Tl Hyperaccumulation from hydroponics and soil was apparent in two populations. In one of them, it was a highaffinity phenomenon, but it was only apparent at high Tl exposure levels, and not associated with enhanced root-to-shoot translocation in the other one. There was no considerable inter-population variation in Cs tolerance and accumulation, except that one population showed a relatively low Cs retention in its roots under low exposure. Conclusions Tl Hyperaccumulation and hypertolerance are population-specific traits in B. laevigata. Cs accumulation and tolerance are less variable and largely uncorrelated with Tl accumulation and tolerance
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Molecular mechanisms of metal Hyperaccumulation in plants
New Phytologist, 2009Co-Authors: Nathalie Verbruggen, Cedric Hermans, Henk SchatAbstract:Contents\n\n* Summary 759\n* I. Hyperaccumulation: the phenomenon 759\n* II. Macroevolution of Hyperaccumulation 760\n* III. Microevolution of Hyperaccumulation: variation within hyperaccumulator species 760\n* IV. Genetic analysis of trace metal accumulation and tolerance 761\n* V. Mechanisms of trace metal accumulation 762\n* VI. General discussion and research perspectives 769\n* Acknowledgements 772\n* References 772\nSummary\nMetal hyperaccumulator plants accumulate and detoxify extraordinarily high concentrations of metal ions in their shoots. Metal Hyperaccumulation is a fascinating phenomenon, which has interested scientists for over a century. Hyperaccumulators constitute an exceptional biological material for understanding mechanisms regulating plant metal homeostasis as well as plant adaptation to extreme metallic environments. Our understanding of metal Hyperaccumulation physiology has recently increased as a result of the development of molecular tools. This review presents key aspects of our current understanding of plant metal – in particular cadmium (Cd), nickel (Ni) and zinc (Zn) – Hyperaccumulation.
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intraspecific variation of metal preference patterns for Hyperaccumulation in thlaspi caerulescens evidence from binary metal exposures
Plant and Soil, 2008Co-Authors: Ana G L Assuncao, Wilma Ten M Bookum, Riet Vooijs, Petra M Bleeker, Henk SchatAbstract:Metal preferences with regard to accumulation were compared between populations of the heavy metal hyperaccumulator Thlaspi caerulescens, originating from calamine, serpentine and non-metalliferous soils. Plants were exposed for 3 weeks to factorial combinations of concentrations of different metals in binary mixture in hydroponics. The nature and degree of the interactions varied significantly between populations. In the calamine, non-Cd/Ni-hyperaccumulating population, La Calamine, there were no one-sided or mutual antagonistic interactions among the metals with regard to their accumulation in the plant. In three other populations capable of Cd and Ni Hyperaccumulation, from calamine, serpentine and non-metalliferous soil respectively, there were one-sided or mutual antagonistic interactions between Cd and Zn, Cd and Ni, and Ni and Zn, possibly resulting from competition for transporters involved in uptake or plant-internal transport. Significant synergistic interactions, probably resulting from regulation of transporter expression, were also found, particularly in the La Calamine population. All the populations seemed to express a more or less Zn-specific high-affinity system. The serpentine and the non-metallicolous populations seemed to posses low-affinity systems with a preference for Cd and Zn over Ni, one of which may be responsible for the Ni Hyperaccumulation of the serpentine population in its natural environment. The calamine population from Ganges also seemed to express a strongly Cd-specific high-affinity system which is in part responsible for the Cd-Hyperaccumulation phenotype exhibited by this population in its natural environment.
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thlaspi caerulescens an attractive model species to study heavy metal Hyperaccumulation in plants
New Phytologist, 2003Co-Authors: Adaildo Gomes D'assunção, Henk Schat, Mark G. M. AartsAbstract:Studying heavy metal Hyperaccumulation is becoming more and more interesting for ecological, evolutionary, nutritional, and environmental reasons. One model species, especially in the era of high throughput genomics, transcriptomics, proteomics and metabolomics technologies, would be very advantageous. Although there are several hyperaccumulator species known, there is no single model species yet. The Zn, Cd and Ni hyperaccumulator species Thlaspi caerulescens has been studied to a great extent, especially for Zn and Cd Hyperaccumulation and tolerance. Its physiological, morphological and genetic characteristics, and its close relationship to Arabidopsis thaliana, the general plant reference species, make it an excellent candidate to be the plant heavy metal Hyperaccumulation model species.
Antony Van Der Ent - One of the best experts on this subject based on the ideXlab platform.
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Blepharidium guatemalense, an obligate nickel hyperaccumulator plant from non-ultramafic soils in Mexico
Chemoecology, 2021Co-Authors: Dulce Montserrat Navarrete Gutiérrez, Antony Van Der Ent, A. Joseph Pollard, Michel Cathelineau, Marie-noëlle Pons, Jesús A. Cuevas Sánchez, Guillaume EchevarriaAbstract:Nickel Hyperaccumulation in Blepharidium guatemalense Standl. (Rubiaceae) was found in the tropical forests of south-eastern Mexico. This study aimed to document the geographic extent of nickel Hyperaccumulation in this species, to understand its process of Hyperaccumulation and to explore nickel distribution within the tissues of this plant. To accomplish these objectives, a complete non-destructive elemental screening of herbarium specimens was performed with a hand-held X-ray fluorescence spectrometer. Besides, rhizosphere soils and plant tissues were collected in Mexico and analyzed for physical–chemical parameters. Finally, elemental distribution maps of nickel and other elements in plant tissues were obtained by X-ray fluorescence spectroscopy and microscopy. This study revealed that Blepharidium guatemalense is distributed throughout Chiapas, Tabasco and Campeche, reaching the maximum nickel concentration in leaves (4.3 wt%) followed by roots and seeds (2.0 wt%) and bark (1.8 wt%). Simultaneous Hyperaccumulation of cobalt and nickel was found in 15% of the herbarium specimens. Blepharidium guatemalense has uncommon re-distribution mechanisms via phloem since this tissue is the highest nickel-enriched from all parts of the plant (from roots to leaves). A high total nickel (mean of 610 µg g^−1) was found in rhizosphere soils even though no evidence of ophiolite emplacement in that area has been reported. Blepharidium guatemalense represents the first hypernickelophore (> 1 wt% Ni) to be reported as growing in soils that are neither ultramafic nor enriched by anthropogenic pollutants.
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Novel Insights Into the Hyperaccumulation Syndrome in Pycnandra (Sapotaceae)
Frontiers in plant science, 2020Co-Authors: Sandrine Isnard, Guillaume Echevarria, Bruno Fogliani, Laurent L'huillier, Adrian L. D. Paul, Jérôme Munzinger, Peter D. Erskine, Vidiro Gei, Tanguy Jaffré, Antony Van Der EntAbstract:The discovery of nickel Hyperaccumulation, in Pycnandra acuminata, was the start of a global quest in this fascinating phenomenon. Despite recent advances in the physiology and molecular genetics of Hyperaccumulation, the mechanisms and tolerance of Ni accumulation in the most extreme example reported to date, P. acuminata, remains enigmatic. We conducted a hydroponic experiment to establish Ni tolerance levels and translocation patterns in roots and shoots of P. acuminata, and analyzed elemental partitioning to gain insights into Ni regulation. We combined a phylogeny and foliar Ni concentrations to assess the incidence of Hyperaccumulation within the genus Pycnandra. Hydroponic dosing experiments revealed that P. acuminata can resist extreme Ni concentrations in solution (up to 3,000 µM), and dosing at 100 µM Ni was beneficial to growth. All plant parts were highly enriched in Ni, but the latex had extreme Ni concentrations (124,000 µg g-1). Hyperaccumulation evolved independently in only two subgenera and five species of the genus Pycnandra. The extremely high level of Ni tolerance is posited to derive from the unique properties of laticifers. The evolutionary and ecological significance of Ni Hyperaccumulation in Pycnandra is discussed in light of these findings. We suggest that Ni-rich laticifers might be more widespread in the plant kingdom and that more investigation is warranted.
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Phylogenetic and geographic distribution of nickel Hyperaccumulation in neotropical Psychotria
American Journal of Botany, 2019Co-Authors: Grace Mccartha, Charlotte Taylor, Antony Van Der Ent, Guillaume Echevarria, Dulce Navarrete Gutiérrez, A. Joseph PollardAbstract:Premise Hyperaccumulation of heavy metals in plants has never been documented from Central America or Mexico. Psychotria grandis, P. costivenia, and P. glomerata (Rubiaceae) have been reported to hyperaccumulate nickel in the Greater Antilles, but they also occur widely across the neotropics. The goals of this research were to investigate the geographic distribution of Hyperaccumulation in these species and explore the phylogenetic distribution of Hyperaccumulation in this clade by testing related species. Methods Portable x‐ray fluorescence (XRF) spectroscopy was used to analyze 565 specimens representing eight species of Psychotria from the Missouri Botanical Garden herbarium. Results Nickel Hyperaccumulation was found in specimens of Psychotria costivenia ranging from Mexico to Costa Rica and in specimens of P. grandis from Guatemala to Ecuador and Venezuela. Among related species, nickel Hyperaccumulation is reported for the first time in P. lorenciana and P. papantlensis, but no evidence of Hyperaccumulation was found in P. clivorum, P. flava, or P. pleuropoda. Previous reports of Hyperaccumulation in P. glomerata appear to be erroneous, resulting from taxonomic synonymy and specimen misidentification. Conclusions Hyperaccumulation of nickel by Psychotria is now known to occur widely from southern Mexico through Central America to northwestern South America, including some areas not known to have ultramafic soils. Novel aspects of this research include the successful prediction of new hyperaccumulator species based on molecular phylogeny, use of XRF technology to nondestructively obtain elemental data from herbarium specimens, and documentation of previously unknown areas of ultramafic or nickel‐rich soil based on such data.
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Copper and cobalt accumulation in plants: a critical assessment of the current status of knowledge
New Phytologist, 2017Co-Authors: Bastien Lange, Nathalie Verbruggen, Antony Van Der Ent, Guillaume Echevarria, Alan John Martin Baker, Grégory Mahy, François Malaisse, Pierre Meerts, Olivier Pourret, Michel-pierre FauconAbstract:This review synthesizes contemporary understanding of Cu-Co tolerance and accumulation in plants. Accumulation of foliar Cu and Co to >300 μg g-1 is exceptionally rare globally, and known principally from the Copperbelt of Central Africa. Cobalt accumulation is also observed in a limited number of Ni hyperaccumulator plants occurring on ultramafic soils around the world. None of the putative Cu or Co hyperaccumulator plants appears to comply with the fundamental principle of Hyperaccumulation as foliar Cu-Co accumulation is strongly dose-dependent. Abnormally high plant-tissue Cu concentration occurs only when plants areexposed to high soil Cu concentrations with a low shoot translocation factor. Most Cu tolerant plants are Excluders sensu Baker and therefore setting threshold values for Cu Hyperaccumulation is not informative. Abnormal accumulation of Co occurs under similar circumstances in the Copperbelt of the DR Congo, however, Co tolerant plants behave physiologically as Indicators sensu Baker and sporadically coincides with Ni Hyperaccumulation on ultramafic soils. Practical application of Cu-Co accumulator plants in phytomining is limited due to their dose-dependent accumulation characteristics, although for Co trials may be warranted on highly Co-contaminated minerals wastes because it its high metal value.
Josep Escarre - One of the best experts on this subject based on the ideXlab platform.
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Zinc tolerance and Hyperaccumulation in F-1 and F-2 offspring from intra and interecotype crosses of Thlaspi caerulescens
New Phytologist, 2005Co-Authors: Helene Frerot, C Lefebvre, Christian Collin, Christophe Petit, A. Dos Santos, Josep EscarreAbstract:The relationship between zinc (Zn) tolerance and Hyperaccumulation in Thlaspi caerulescens was investigated from F-1 and F-2 crosses within and among metallicolous and nonmetallicolous Mediterranean populations. F-1 offspring were grown on increasingly Zn-enriched soils to test Zn enrichment effects, and many families of F-2 offspring were grown on a Zn-rich soil. Tolerance of F-1 offspring depended on stress intensity. Tolerance of interecotype crosses was intermediate between that of the intraecotype crosses. No difference in Zn accumulation appeared among the F-1 offspring from the three crosses involving metallicolous parents. Otherwise, none of these offspring exceeded the Zn Hyperaccumulation threshold (10 000 mg kg(-1)), unlike the nonmetallicolous ones. The latter also showed the highest mortality. In some F-2 families from interecotype crosses, Hyperaccumulation values exceeded 15 000 mg kg(-1) in nontolerant offspring, whereas tolerant offspring displayed lower values (c. 10 000 mg kg(-1)). There was no difference between tolerant and nontolerant offspring when they showed low Hyperaccumulation. Therefore, the relationship between tolerance and Hyperaccumulation in F-1 and F-2 crosses depended on the Hyperaccumulation level of plants.
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zinc tolerance and Hyperaccumulation in f1 and f2 offspring from intra and interecotype crosses of thlaspi caerulescens
New Phytologist, 2004Co-Authors: Helene Frerot, C Lefebvre, Christian Collin, Dos A Santos, Christophe Petit, Josep EscarreAbstract:Summary • The relationship between zinc (Zn) tolerance and Hyperaccumulation in Thlaspi caerulescens was investigated from F1 and F2 crosses within and among metallicolous and nonmetallicolous Mediterranean populations. • F1 offspring were grown on increasingly Zn-enriched soils to test Zn enrichment effects, and many families of F2 offspring were grown on a Zn-rich soil. • Tolerance of F1 offspring depended on stress intensity. Tolerance of interecotype crosses was intermediate between that of the intraecotype crosses. No difference in Zn accumulation appeared among the F1 offspring from the three crosses involving metallicolous parents. Otherwise, none of these offspring exceeded the Zn Hyperaccumulation threshold (10 000 mg kg−1), unlike the nonmetallicolous ones. The latter also showed the highest mortality. In some F2 families from interecotype crosses, Hyperaccumulation values exceeded 15 000 mg kg−1 in nontolerant offspring, whereas tolerant offspring displayed lower values (c. 10 000 mg kg−1). There was no difference between tolerant and nontolerant offspring when they showed low Hyperaccumulation. • Therefore, the relationship between tolerance and Hyperaccumulation in F1 and F2 crosses depended on the Hyperaccumulation level of plants.
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Zinc and cadmium accumulation in controlled crosses between metallicolous and nonmetallicolous populations of Thlaspi caerulescens (Brassicaceae)
New Phytologist, 2003Co-Authors: Helene Frerot, C Lefebvre, Christophe Petit, W. Gruber, C. Collin, Josep EscarreAbstract:# Growth and heavy metal (Zn and Cd) Hyperaccumulation were investigated in metallicolous and nonmetallicolous Mediterranean populations of Thlaspi caerulescens (Brassicaceae), and in offspring from controlled crosses between these populations. # • Seeds for the growth and crossing experiments were collected from a number of sites varying in heavy metal contamination. Tissue Zn and Cd content was determined by atomic absorption spectrophotometry. # • Offspring from crosses between nonmetallicolous populations had the highest Zn concentration (c. 30 000 µg g−1), compared with 20 000 µg g−1 for the nonmetallicolous parents. The metallicolous parents and the other crosses had only 10 000 µg g−1. Offspring from crosses including a nonmetallicolous parent still had a significantly higher Zn uptake than the metallicolous parents. A trend towards a higher Cd uptake was observed in offspring from crosses with a metallicolous parent. # • We suggest that the most probable hypothesis is that the differences in Zn Hyperaccumulation between crosses could be explained by a monogenic system with two alleles. The dominant allele would restrict Zn Hyperaccumulation at 10 000 µg g−1 whereas the recessive allele would be responsible for a two to three-fold increase in Zn Hyperaccumulation. Alternatively, the existence of modifier genes could explain the differences between offspring from crosses between nonmetallicolous populations and their respective field parents. The results suggest that plant breeding applied to this species could help to improve Zn phytoextraction.
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zinc and cadmium accumulation in controlled crosses between metallicolous and nonmetallicolous populations of thlaspi caerulescens brassicaceae
New Phytologist, 2003Co-Authors: Helene Frerot, C Lefebvre, Christian Collin, Christophe Petit, W. Gruber, Josep EscarreAbstract:Growth and heavy metal (Zn and Cd) Hyperaccumulation were investigated in metallicolous and nonmetallicolous Mediterranean populations of Thlaspi caerulescens (Brassicaceae), and in offspring from controlled crosses between these populations. Seeds for the growth and crossing experiments were collected from a number of sites varying in heavy metal contamination. Tissue Zn and Cd content was determined by atomic absorption spectrophotometry. Offspring from crosses between nonmetallicolous populations had the highest Zn concentration (c. 30 000 μg g -1), compared with 20 000 μg g -1 for the nonmetallicolous parents. The metallicolous parents and the other crosses had only 10 000 μg g -1. Offspring from crosses including a nonmetallicolous parent still had a significantly higher Zn uptake than the metallicolous parents. A trend towards a higher Cd uptake was observed in offspring from crosses with a metallicolous parent. We suggest that the most probable hypothesis is that the differences in Zn Hyperaccumulation between crosses could be explained by a monogenic system with two alleles. The dominant allele would restrict Zn Hyperaccumulation at 10 000 μg g -1 whereas the recessive allele would be responsible for a two to three-fold increase in Zn Hyperaccumulation. Alternatively, the existence of modifier genes could explain the differences between offspring from crosses between nonmetallicolous populations and their respective field parents. The results suggest that plant breeding applied to this species could help to improve Zn phytoextraction. © New Phytologist (2003).
