Bin Liao

Sun Yat-Sen University, Shengcheng, Guangdong, China

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Publications (34)92.79 Total impact

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    ABSTRACT: Cysteine (Cys)-rich proteins (CRPs) are frequently associated with plant defense and stress resistance. Viola baoshanensis is a cadmium (Cd) hyper-accumulating plant whose CRPs-based defense systems are so far poorly understood. Next generation sequencing (NGS) techniques and a specialist searching tool, CrpExcel, were employed for identifying CRPs in V. baoshanensis. The transcriptome sequences of V. baoshanensis were assembled primarily from 454FLX/Hiseq2000 reads of plant cDNA sequencing libraries. CrpExcel was then used to search the ORFs and 9687 CRPs were identified, and included zinc finger (ZF) proteins, lipid transfer proteins, thaumatins and cyclotide precursors. Real-time PCR results showed that all CRP genes tested are constitutively expressed, but the genes of defensive peptides showed greater up-regulated expression than those of ZF-proteins in Cd- and/or wounding (Wd) treatments of V. baoshanensis seedlings. The NGS-derived sequences of cyclotide precursor genes were verified by RT-PCR and ABI3730 sequencing studies, and 32 novel cyclotides were identified in V. baoshanensis. In general, the metal-binding sites of ZF-containing CRPs also represented the potential vulnerable targets of toxic metals. This study provides broad insights into CRPs-based defense systems and stress-vulnerable targets in V. baoshanensis. It now brings the number of cyclotide sequences in V. baoshanensis to 53 and based on projections from this work, the number of cyclotides in the Violaceae is now conservatively estimated to be >30000. Copyright © 2015 Elsevier GmbH. All rights reserved.
    Journal of Plant Physiology 04/2015; 178(2015):17-26. DOI:10.1016/j.jplph.2015.01.017 · 2.77 Impact Factor
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    ABSTRACT: A total of 455 agricultural soil samples from four nonferrous mines/smelting sites in Shaoguan City, China, were investigated for concentrations of 10 heavy metals (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, and Zn). The mean concentrations of the metals were 72.4, 5.16, 13.3, 54.8, 84.5, 1.52, 425, 28.2, 529, and 722 mg kg−1, respectively. The values for As, Cd, Hg, Pb, and Zn were more than 8 and 1.5 times higher than their background values in this region and the limit values of Grade II soil quality standard in China, respectively. Estimated ecological risks based on contamination factors and potential ecological risk factors were also high or very high for As, Cd, Hg, and Pb. Multivariate analysis (Pearson's correlation analysis, hierarchical cluster analysis, and principal component analysis) strongly implied three distinct groups; i.e., As/Cu/Hg/Zn, Co/Cr/Mn/Ni, and Cd/Pb. Local anomalies for As, Cu, Hg, and Zn by a probably anthropogenic source (identified as mining activity), Co, Cr, Mn, and Ni by natural contribution, and a mixed source for Cd and Pb, were identified. This is one of the few studies with a focus on potential sources of heavy metals in agricultural topsoil around mining/smelting sites, providing evidence for establishing priorities in the reduction of ecological risks posed by heavy metals in Southern China and elsewhere.
    Soil and Sediment Contamination 01/2015; 24(1). DOI:10.1080/15320383.2014.914152 · 0.58 Impact Factor
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    ABSTRACT: Main conclusion Two high-throughput tools harvest hundreds of novel cyclotides and analogues in plants. Cyclotides are gene-encoded backbone-cyclized polypeptides displaying a diverse range of bioactivities associated with plant defense. However, genome-scale or database-scale evaluations of cyclotides have been rare so far. Here, a novel time-efficient Perl program, CyPerl, was developed for searching cyclotides from predicted ORFs of 34 available plant genomes and existing plant protein sequences from Genbank databases. CyPerl-isolated sequences were further analyzed by removing repeats, evaluating their cysteine-distributed regions (CDRs) and comparing with CyBase-collected cyclotides in a user-friendly Excel (Microsoft Office) template, CyExcel. After genome-screening, 186 ORFs containing 145 unique cyclotide analogues were identified by CyPerl and CyExcel from 30 plant genomes tested from 10 plant families. Phaseolus vulgaris and Zea mays were the richest two species containing cyclotide analogues in the plants tested. After screening protein databases, 266 unique cyclotides and analogues were identified from seven plant families. By merging with 288 unique CyBase-listed cyclotides, 510 unique cyclotides and analogues were obtained from 13 plant families. In total, seven novel plant families containing cyclotide analogues and 202 novel cyclotide analogues were identified in this study. This study has established two Blast-independent tools for screening cyclotides from plant genomes and protein databases, and has also significantly widened the plant distribution and sequence diversity of cyclotides and their analogues.
    Planta 12/2014; DOI:10.1007/s00425-014-2229-5 · 3.38 Impact Factor
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    ABSTRACT: Analysis of the phylogenetic structure of biological communities by examining the extent to which community members are more closely related (phylogenetically clustered) or less closely related (phylogenetically overdispersed) than expected by chance has recently been proven to be a promising approach to gain insight into the factors governing the community assembly. However, to date there aren't any studies that have quantitatively examined the community structure of soil nematodes in a phylogenetic framework, despite their crucial roles in soil food webs and nutrient cycling processes. Here, we explored the phylogenetic structures of soil nematode communities along a successional gradient in an unreclaimed copper (Cu) mine tailings site to reveal the potential determinants of the soil nematode community assembly. Unexpectedly, we found little evidence that the phylogenetic distance of the co-occurring soil nematodes increased along this gradient. In contrast, phylogenetic structures of the soil nematode communities along the gradient appeared to show a weak tendency toward clustering (i.e. nematodes tend to co-occur with other closely related nematodes more often than expected by chance). On the other hand, when different soil nematode groups characterized by feeding habits were taken into account separately, we unveiled contrasting phylogenetic community structures: bacterial-feeding (BF), plant-feeding (PF), and omnivore-predator (OP) nematode communities tended to be phylogenetically clustered; whereas, fungal-feeding (FF) nematode communities exhibited a tendency toward phylogenetic overdispersion. Moreover, the net relatedness indices of nematode communities characterized by different feeding habits were shown to be correlated with distinct soil chemical properties (such as diethylene triamine pentaacetic acid extractable Cu for BF and cation exchange capacity for FF), indicating that the assembly processes of these communities were not neutral and might have been largely driven by the respective soil chemical properties. Collectively, our results provided novel insight into the factors driving the assembly of soil nematode communities, highlighting the potential for future studies on nematodes to benefit from a community phylogenetics approach.
    Soil Biology and Biochemistry 10/2014; 77:179–186. DOI:10.1016/j.soilbio.2014.06.007 · 4.41 Impact Factor
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    ABSTRACT: In Arabidopsis thaliana, acyl-CoA-binding proteins (ACBPs) are encoded by a family of six genes (ACBP1 to ACBP6), and are essential for diverse cellular activities. Recent investigations suggest that the membrane-anchored ACBPs are involved in oxygen sensing by sequestration of group VII ethylene-responsive factors under normoxia. Here, we demonstrate the involvement of Arabidopsis ACBP3 in hypoxic tolerance. ACBP3 transcription was remarkably induced following submergence under both dark (DS) and light (LS) conditions. ACBP3-overexpressors (ACBP3-OEs) showed hypersensitivity to DS, LS and ethanolic stresses, with reduced transcription of hypoxia-responsive genes as well as accumulation of hydrogen peroxide in the rosettes. In contrast, suppression of ACBP3 in ACBP3-KOs enhanced plant tolerance to DS, LS and ethanol treatments. By analyses of double combinations of OE-1 with npr1-5, coi1-2, ein3-1 as well as ctr1-1 mutants, we observed that the attenuated hypoxic tolerance in ACBP3-OEs was dependent on NPR1- and CTR1-mediated signaling pathways. Lipid profiling revealed that both the total amounts and very-long-chain species of phosphatidylserine (C42:2- and C42:3-PS) and glucosylinositolphosphorylceramides (C22:0-, C22:1-, C24:0-, C24:1-, and C26:1-GIPC) were significantly lower in ACBP3-OEs but increased in ACBP3-KOs upon LS exposure. By microscale thermophoresis analysis, the recombinant ACBP3 protein bound VLC acyl-CoA esters with high affinities in vitro. Further, a knockout mutant of MYB30, a master regulator of very-long-chain fatty acid (VLCFA) biosynthesis, exhibited enhanced sensitivities to LS and ethanolic stresses, phenotypes that were ameliorated by ACBP3-RNAi. Taken together, these findings suggest that Arabidopsis ACBP3 participates in plant response to hypoxia by modulating VLCFA metabolism.This article is protected by copyright. All rights reserved.
    The Plant Journal 10/2014; 81(1). DOI:10.1111/tpj.12692 · 6.82 Impact Factor
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    ABSTRACT: The oxidative dissolution of sulfide minerals (principally pyrite) is responsible for the majority of acid metalliferous drainage from mine sites, which represents a significant environmental problem worldwide. Understanding the complex biogeochemical processes governing natural pyrite oxidation is critical to not only solving this problem but also the industrial bioleaching of sulfide minerals. To this end, we conducted a simulated experiment of natural pyrite oxidative dissolution. Pyrosequencing analysis of microbial community revealed a distinct succession across three stages. At the early stage, a newly proposed genus, Tumebacillus (which can use sodium thiosulfate and sulfite as the sole electron donors), dominated the microbial community. At the mid-stage, Alicyclobacillus (the fifth most abundant genus at the early stage), became the most dominant genus, whilst Tumebacillus was still ranked as the second most abundant. At the final stage, the microbial community was dominated by Ferroplasma (the tenth most abundant genus at the early stage). Our geochemical and mineralogical analyses indicated that exchangeable heavy metals increased as the oxidation progressed and that some secondary sulfate minerals (including jarosite and magnesiocopiapite) were formed at the final stage of the oxidation sequence. Additionally, we propose a comprehensive model of biogeochemical processes governing the oxidation of sulfide minerals.
    Environmental Science & Technology 04/2014; 48(10). DOI:10.1021/es500154z · 5.48 Impact Factor
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    ABSTRACT: Background and Aims In plants, hyperaccumulation of metals and metalloids is considered to be a positively selected trait for defense against herbivory and parasitism. However, few investigations have been performed on the patterns of molecular polymorphism of genes putatively related to the hyperaccumulation phenotype. Methods We explored the genetic polymorphism of 32 accessions across China of the arsenic (As)-hyperaccumulator fern Pteris vittata. Nineteen loci, 9 of which code for proteins putatively involved in As hyperaccumulation, were sequenced. Results A relatively high polymorphism was detected in genes putatively related to As accumulation. No evidence for positive selection was present at any of the investigated loci. Mantel’s test performed on genetic distances versus geographical, soil As concentration, translocation and bioaccumulation factor distances showed a partial geographical clustering of populations but no correlation between genetic distances and edaphic or hyperaccumulation parameters. Conclusions Our study suggest that constitutive As hyperaccumulation in P. vittata, though variable between accessions, did not produce detectable signatures on protein coding sequences of gene putatively related to As hyperaccumulation. These data may be in agreement with an ancient origin of the hyperaccumulation phenotype and, at least for the protein sequence, a relaxation of selective pressure on genes implied in this trait.
    Plant and Soil 12/2013; 373(1-2). DOI:10.1007/s11104-013-1810-1 · 3.24 Impact Factor
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    ABSTRACT: The effect of indigenous arbuscular mycorrhizal (AM) fungi on lead (Pb) and cadmium (Cd) uptake by the hyperaccumulator plant Viola baoshanensis was studied in greenhouse pot experiments. Seedlings of V. baoshanensis inoculated without or with indigenous AM fungi were grown in paddy soil with the addition of Pb at 0, 500, 1000 and 1500 mg kg(-1), or of Cd at 0, 50,100, 200 mg kg(-1), or in mine soil with the addition of phosphorus at 0, 50, 250, 500 mg kg(-1). AM colonization increased shoot biomass at low phosphorus levels, and this beneficial effect was diminished or reversed by high phosphorus availability. AM colonization decreased shoot Cd concentrations regardless of the availability of Cd and phosphorus, but the mechanisms involved varied with Cd availability. At low Cd bioavailability, reduced Cd uptake was due to decreased Cd translocation from the roots to the shoots, whereas that was attributed to reduced root uptake at high Cd bioavailability. In contrast, the effect of AM colonization on shoot Pb varied with the availability of phosphorous and Pb. Our results show that the interactions between V. baoshanensis and indigenous AM fungi were modified by the availability of Pb, Cd and phosphorus.
    Journal of Environmental Monitoring 08/2012; 14(9):2497-504. DOI:10.1039/c2em30333g · 2.09 Impact Factor
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    ABSTRACT: BACKGROUND: Patterns of genetic divergence between populations of facultative metallophytes have been investigated extensively. However, most previous investigations have focused on a single plant species making it unclear if genetic divergence shows common patterns or, conversely, is species-specific. The herbs Rumex acetosa L. and Commelina communis L. are two pseudo-metallophytes thriving in both normal and cupriferous soils along the middle and lower reaches of the Yangtze River in China. Their non-metallicolous and metallicolous populations are often sympatric thus providing an ideal opportunity for comparative estimation of genetic structures and divergence under the selective pressure derived from copper toxicity. RESULTS: In the present study, patterns of genetic divergence of R. acetosa and C. communis, including metal tolerance, genetic structure and genetic relationships between populations, were investigated and compared using hydroponic experiments, AFLP, ISSR and chloroplast genetic markers. Our results show a significant reduction in genetic diversity in metallicolous populations of C. communis but not in R. acetosa. Moreover, genetic differentiation is less in R. acetosa than in C. communis, the latter species also shows a clustering of its metallicolous populations. CONCLUSIONS: We propose that the genetic divergences apparent in R. acetosa and C. communis, and the contrasting responses of the two species to copper contamination, might be attributed to the differences in their intrinsic physiological and ecological properties. No simple and generalised conclusions on genetic divergence in pseudo-metallophytes can thus be drawn.
    BMC Evolutionary Biology 06/2012; 12(1):84. DOI:10.1186/1471-2148-12-84 · 3.41 Impact Factor
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    ABSTRACT: • Arsenic (As) contamination of rice (Oryza sativa) is a worldwide concern and elucidating the molecular mechanisms of As accumulation in rice may provide promising solutions to the problem. Previous studies using microarray techniques to investigate transcriptional regulation of plant responses to As stress have identified numerous differentially expressed genes. However, little is known about the metabolic and regulatory network remodelings, or their interactions with microRNA (miRNA) in plants upon As(III) exposure. • We used Illumina sequencing to acquire global transcriptome alterations and miRNA regulation in rice under As(III) treatments of varying lengths of time and dosages. • We found that the response of roots was more distinct when the dosage was varied, whereas that of shoots was more distinct when the treatment time was varied. In particular, the genes involved in heavy metal transportation, jasmonate (JA) biosynthesis and signaling, and lipid metabolism were closely related to responses of rice under As(III) stress. Furthermore, we discovered 36 new As(III)-responsive miRNAs, 14 of which were likely involved in regulating gene expression in transportation, signaling, and metabolism. • Our findings highlight the significance of JA signaling and lipid metabolism in response to As(III) stress and their regulation by miRNA, which provides a foundation for subsequent functional research.
    New Phytologist 04/2012; 195(1):97-112. DOI:10.1111/j.1469-8137.2012.04154.x · 6.55 Impact Factor
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    ABSTRACT: Averrhoa carambola L., a high-biomass tropical tree, has recently been shown to be a strong accumulator of cadmium (Cd) and has great potential for Cd phytoextraction. In the present study, field studies and a controlled-environment experiment were combined to establish the extent of variation in Cd tolerance and accumulation at the cultivar level using 14 to 19 cultivars of A. carambola. The results indicated that all cultivars tested could accumulate Cd at high but different levels, and that Cd tolerance also varied greatly between these cultivars. It is confirmed that the high Cd tolerance and accumulation capacity are species-level and constitutional traits in A. carambola. However, no correlation was detected between tolerance index and accumulation of Cd in different cultivars, suggesting that the two traits are independent in this woody Cd accumulator. More importantly, cultivar Wuchuan Sweet (WCT) was shown to have the highest Cd-extraction potential; it yielded a high shoot biomass of 30 t ha(-1) in 230 d, and extracted 330 g ha(-1) Cd in the aerial tissues grown in Cd-contaminated field soil, which accounted for 12.8% of the total soil Cd in the top 20 cm of the soil profile.
    Journal of Environmental Monitoring 06/2011; 13(6):1723-9. DOI:10.1039/c1em10054h · 2.09 Impact Factor
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    ABSTRACT: Previous studies have shown that the application of soil amendments is efficient in reducing acidity and heavy metal bioavailability in mine soils. However, it remains a challenge for environmentalists to predict accurately and control economically the re-acidification in re-vegetated mine soils. In this study, net acid generation (NAG) test and bioassay technique were employed to assess the effectiveness of the amendments [including lime, N-P-K (nitrogen, phosphorous and potassium) fertilizer, phosphate and river sediment] on re-acidification and heavy metal immobilization in an extremely acid (pH < 3) mine soil. Our results suggested that NAG test was a rapid and accurate approach to assess the effectiveness of the amendments on re-acidification potential of the mine soil. Interestingly, it was found that phosphate and river sediment played quite specific roles in preventing the re-acidification in the mine soil. In addition, the results also indicated that the addition of 25 t ha(-1) lime combined with river sediment (30%) might be an economical method to successfully control the acidification and re-acidification in the extremely acid mine soil, allowing the re-establishment of the plants. Collectively, our results implied that the combined use of NAG test and bioassay assessment was effective in evaluating a reclamation strategy for extremely acidic mine soils.
    Journal of Environmental Monitoring 05/2011; 13(7):1876-83. DOI:10.1039/c1em10028a · 2.09 Impact Factor
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    ABSTRACT: Cadmium (Cd) accumulation by terrestrial higher plants is an intriguing phenomenon that may be exploited for phytoextraction of Cd-contaminated soils. Characterizing the physiological processes responsible for elevated concentrations of Cd in shoots is a first step towards a comprehensive understanding of the mechanisms underlying Cd accumulation in plants and may eventually improve the efficiency of phytoextraction. Woody species that can accumulate Cd have been recently recommended as good candidates for phytoextraction of Cd-contaminated soils. However, little is known about the mechanisms of Cd accumulation by woody species. In an attempt to understand the physiological processes contributing to Cd accumulation in woody species, Cd uptake and translocation by a novel tropical Cd-accumulating tree, star fruit (Averrhoa carambola) were characterized and compared with those of a non-Cd-accumulating tree (Clausena lansium). Our results showed that A. carambola had higher Cd uptake and root-to-shoot translocation efficiencies than C. lansium, which might account for its greater Cd-accumulating capacity. Furthermore, Cd accumulation by A. carambola was not significantly affected by zinc (Zn), whereas Zn accumulation was greatly lowered by Cd. This phenomenon could not be fully explained by a simple competition between Cd2+ and Zn2+, implying the existence of a transport system with a preference for Cd over Zn. Collectively, our results indicate that A. carambola has noteworthy physiological traits associated with accumulation of Cd to high levels.
    Environmental and Experimental Botany 02/2011; 71(3):352-358. DOI:10.1016/j.envexpbot.2011.02.001 · 3.00 Impact Factor
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    ABSTRACT: Viola baoshanensis is one of the most rare cadmium (Cd) hyperaccumulators, however, it is hard to propagate. Micropropagation has been applied to solve the problems with propagation of a few heavy metal hyperaccumulators. Therefore there is a high likelihood that micropropagation may offer a suitable method for large-scale propagation of V. baoshanensis To test this hypothesis, three types of explants were used for shoot regeneration and various combinations of four plant growth regulators were used to improve shoot regeneration efficiency from leaflet of V. baoshanensis. Best shoot regeneration efficiency was obtained by incubating leaflet in a 1/2 MS medium supplemented with 2.5 oM BA + 2.5 microM IBA, therein shoot regeneration rate was 70.9% and the number of shoots formation per explant was 22.4. Rooting was achieved from almost all regenerated shoot growing on 1/2 MS medium without plant growth regulator. Micropropagated seedlings were acclimatized under greenhouse conditions and 95% of them survived and showed no visible morphological variation compared to their donor plant. Furthermore, there were no significant differences between regenerated and seed-germinated V. baoshanensis in Cd tolerance and accumulation. These results suggested that an efficient and rapid micropropogation system was successfully developed for V. baoshanensis.
    International Journal of Phytoremediation 09/2010; 12(8):761-71. DOI:10.1080/15226510903390486 · 1.47 Impact Factor
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    ABSTRACT: Chinese Brake fern (Pteris vittata) is the first identified and well-known arsenic-hyperaccumulator. It is widely distributed in areas of temperate zone as diploid and of subtropics-tropics zone as tetraploid. Screening 60 individuals from Southern China, eight polymorphic microsatellite markers were developed for the first time by employing fast isolation by AFLP of sequences containing repeats protocol (FIASCO). The number of alleles for each marker ranged from two to seven and one to four bands per individual. Furthermore, five of the loci possess more than two alleles per individual. The results suggested these microsatellite markers provide a useful tool for studying the ongoing genetic variability of this specie as well as mating systems.
    Conservation Genetics Resources 09/2010; 2(S1):65-67. DOI:10.1007/s12686-009-9169-6 · 1.14 Impact Factor
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    ABSTRACT: Viola baoshanensis has been identified as a Cd-hyperaccumulator, however, its ability to accumulate Pb or Zn is less certain. Therefore, this study focused on determining whether or not V. baoshanensis can accumulate Pb or Zn, by means of field survey, hydroponic and pot experiments. In addition, we also tried to obtain further information on the Cd hyperaccumulating characteristics of this species. Under field conditions, V. baoshanensis accumulated on average 1090 mg Cd kg(-1), 1902 mg Pb kg(-1) and 3428 mg Zn kg(-1) in its shoots, respectively. In hydroponic and pot experiments, V. baoshanensis showed high tolerance to Cd, Pb, and Zn, as well as the ability to accumulate exceptionally high concentrations of the three elements in its shoots (> 2% Cd, > 1% Pb, and > 0.5% Zn on a dry matter basis). These results, taken together, suggested that V. baoshanensis is not only a Cd-hyperaccumulator, but also a strong accumulator of Pb and Zn.
    International Journal of Phytoremediation 08/2010; 12(6):574-85. DOI:10.1080/15226510903353195 · 1.47 Impact Factor
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    ABSTRACT: A revegetation program was established at an extreme acidic and metal-toxic pyrite/copper mine wasteland in Guangdong Province, PR China using a combination of four native grass species and one non-native woody species. It was continued and monitored for 2 y. The emphasis was on acidification, metal mobility and nutrient accumulation in the soil-plant system. Our results showed the following: (i) the acid-forming potential of the mine soils decreased steadily with time, which might be due to plant root-induced changes inhibiting the oxidization of sulphide minerals; (ii) heavy metal extractability (diethylene-triamine-pentaacetic acid-extractable Pb and Zn) in the soils increased with time despite an increase in soil pH, which might be attributed to soil disturbance and plant rhizospheric processes, as well as a consequence of the enhanced metal accumulation in plants over time; and (iii) the vegetation cover increased rapidly with time, and plant development accelerated the accumulation of major nutrients (organic matter, total and ammonium-N, and available P and K). The 2-y field experiment demonstrates that direct seeding/planting of native plant species in combination with lime and manure amelioration is a practical approach to the initial establishment of a self-sustaining vegetation cover on this metalliferous and sulphide-bearing mine wasteland. However, heavy metal accumulation in the soil-plant system should be of great concern, and long-term monitoring of ecological risk must be an integral part of such a restoration scheme.
    Chemosphere 08/2010; 80(8):852-9. DOI:10.1016/j.chemosphere.2010.05.055 · 3.50 Impact Factor
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    ABSTRACT: Averrhoa carambola is a high-biomass tropical tree that has been I identified as a Cd accumulator. In the present study, field survey, pot, and hydroponic experiments were conducted to investigate the variation of Cd tolerance and accumulation in cultivars of A carambola as well as its potential for phytoextraction. In the field survey, it was found that concentrations of Cd in aerial tissues of A carambola varied greatly among sites and cultivars The Cd bioconcentration factors (BCFs) and Cd removals by the field-grown A carambola differed significantly among sites but not among cultivars. Nonetheless, all four carambola cultivars investigated were able to accumulate considerably high concentrations of Cd in their shoots, which indicated that the 4-yr-old carambola stands could remove 0 3 to 51 8% of the total Cd content its the top 20-cm sod layer. When cultured in Cd-spiked soils, the carambola cultivar Hua-Di always showed higher Cd tolerance than the other cultivars; however, this tendency was not confirmed by hydroponic experiment. The Cd BCFs of cultivar Thailand grown in sods with 6 and 12 mg Cd kg were highest among cultivars, whereas this trend was reversed at 120 mg Cd kg(-1) treatment Nevertheless, the pot- and hydroponics-grown carambola cultivars generally showed higher capacities to tolerate and accumulate Cc!, compared with the control species The present results indicate that a strong ability to tolerate and accumulate Cd seems to be a trait at the species level in A carambola, although some degree of variances in both Cd tolerance and accumulation exists among cultivars
    Journal of Environmental Quality 07/2010; 39(4). DOI:10.2134/jeq2009.0195 · 2.35 Impact Factor
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    ABSTRACT: Peanut (Arachis hypogaea) allergy is one of the most serious food allergies. Peanut seed protein, Ara h 3, is considered to be one of the most important peanut allergens. Little is known about the temporal and spatial regulation mechanism of Ara h 3 during seed development. In this study, chromatin structure of the Ara h 3 promoter was analyzed to examine its transcriptional regulation. Analysis of transgenic plants of Arabidopsis thaliana expressing Arah3: GUS showed that the Ara h 3 promoter could efficiently direct the seed-specific expression of the GUS reporter gene. Chromatin immunoprecipitation revealed that nucleosomes were depleted at the core promoter of the Ara h 3 upon full activation in the late stage of embryo maturation, which was accompanied by a dramatic decrease of histone acetylation. However, in the early stage of embryo maturation, histone H3 hyperacetylation at the core promoter of Ara h 3 was detected. A decrease of histone H3-K9 dimethylation levels at core promoter of Ara h 3 was also observed with concomitant repression of Ara h 3 in the vegetative tissues. Our results suggest that the histone modification status of Ara h 3 undergoes targeted changes including the increase of histone H3 acetylation and decrease of histone H3-K9 dimethylation in early maturation embryos. In addition, the loss of histone H3 from the proximal promoter of Ara h 3 is associated with its high expression during late embryo maturation.
    Planta 02/2010; 231(5):1049-60. DOI:10.1007/s00425-010-1111-3 · 3.38 Impact Factor
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    ABSTRACT: Averrhoa carambola is a high-biomass tropical tree that has been identified as a Cd accumulator. In the present study, field survey, pot, and hydroponic experiments were conducted to investigate the variation of Cd tolerance and accumulation in cultivars of A. carambola as well as its potential for phytoextraction. In the field survey, it was found that concentrations of Cd in aerial tissues of A. carambola varied greatly among sites and cultivars. The Cd bioconcentration factors (BCFs) and Cd removals by the field-grown A. carambola differed significantly among sites but not among cultivars. Nonetheless, all four carambola cultivars investigated were able to accumulate considerably high concentrations of Cd in their shoots, which indicated that the 4-yr-old carambola stands could remove 0.3 to 51.8% of the total Cd content in the top 20-cm soil layer. When cultured in Cd-spiked soils, the carambola cultivar Hua-Di always showed higher Cd tolerance than the other cultivars; however, this tendency was not confirmed by hydroponic experiment. The Cd BCFs of cultivar Thailand grown in soils with 6 and 12 mg Cd kg(-1) were highest among cultivars, whereas this trend was reversed at 120 mg Cd kg(-1) treatment. Nevertheless, the pot- and hydroponics-grown carambola cultivars generally showed higher capacities to tolerate and accumulate Cd, compared with the control species. The present results indicate that a strong ability to tolerate and accumulate Cd seems to be a trait at the species level in A. carambola, although some degree of variances in both Cd tolerance and accumulation exists among cultivars.
    Journal of Environmental Quality 01/2010; 39(4):1262-8. · 2.35 Impact Factor

Publication Stats

213 Citations
92.79 Total Impact Points

Institutions

  • 2006–2015
    • Sun Yat-Sen University
      • • School of Life Sciences
      • • State Key Laboratory of Biocontrol
      • • Key Laboratory of Gene Engineering of the Ministry of Education
      Shengcheng, Guangdong, China