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Rufus L Chaney - One of the best experts on this subject based on the ideXlab platform.

  • growth and metal accumulation of an Alyssum murale nickel hyperaccumulator ecotype co cropped with Alyssum montanum and perennial ryegrass in serpentine soil
    Frontiers in Plant Science, 2016
    Co-Authors: Rufus L Chaney
    Abstract:

    The genus Alyssum (Brassicaceae) contains Ni hyperaccumulators (50), many of which can achieve 30 g kg-1 Ni in dry leaf. Some Alyssum hyperaccumulators are viable candidates for commercial Ni phytoremediation and phytomining technologies. It is not known whether these species secrete organic and/or amino acids into the rhizosphere to solubilize Ni, or can make use of such acids within the soil to facilitate uptake. It has been hypothesized that in fields with mixed plant species, mobilization of metals by phytosiderophores secreted by Graminaceae plants could affect Alyssum Ni, Fe, Cu and Mn uptake. We co-cropped the Ni hyperaccumulator Alyssum murale, non-hyperaccumulator A. montanum and perennial ryegrass in a natural serpentine soil. All treatments had standard inorganic fertilization required for ryegrass growth and one treatment was compost amended. After 4 months A. murale leaves and stems contained 3600 mg kg-1 Ni which did not differ significantly with co-cropping. Overall Ni and Mn concentrations were significantly higher in A. murale than in A. montanum or L. perenne. Copper was not accumulated by either Alyssum species, but L. perenne accumulated up to 10 mg kg-1. A. montanum could not compete with either A. murale or ryegrass, and neither Alyssum species survived in the compost-amended soil. Co-cropping with ryegrass reduced Fe and Mn concentrations in A. murale but not to the extent of either increasing Ni uptake or affecting plant nutrition. The hypothesized Alyssum Ni accumulation in response to phytosiderophores secreted by co-cropped grass did not occur. Our data do not support increased mobilization of Mn by a phytosiderophore mechanism either, but the converse: mobilization of Mn by the Alyssum hyperaccumulator species significantly increased Mn levels in L. perenne. Tilling soil to maximize root penetration, adequate inorganic fertilization and appropriate plant densities are more important for developing efficient phytoremediation and phytomining approaches.

  • Xylem exudate composition and root-to-shoot nickel translocation in Alyssum species
    Plant and Soil, 2013
    Co-Authors: Tiziana Centofanti, Zehra Sayers, Maria Isabel Cabello-conejo, Petra Kidd, Naoko K. Nishizawa, Yusuke Kakei, Allen P. Davis, Richard C. Sicher, Rufus L Chaney
    Abstract:

    Aims An improved understanding of the Ni root-to-shoot translocation mechanism in hyperaccumulators is necessary to increase Ni uptake efficiency for phytoextraction technologies. It has been presumed that an important aspect of Ni translocation and storage involves chelation with organic ligands. It has been reported that exposing several Ni hyperaccumulator species of Alyssum to Ni elicited a large increase in the histidine level of the xylem sap. In later studies it was shown that as time progressed the histidine:Ni ratio dropped considerably. Moreover, previous studies analyzed the relationship between Ni and ligands in plants that were exposed to Ni only for a few hours and therefore obtained results that are unlikely to represent field soils where plants are at steady-state Ni uptake. The aim of this study was to understand the quantitative relationship between Ni and organic ligands in the xylem sap of various Alyssum genotypes or species that reached steady-state Ni uptake after being exposed to Ni in either nutrient solution or serpentine soil for up to 6 weeks. Methods Total Ni concentration, 17 amino acids, 9 organic acids, and nicotianamine were measured in xylem sap of 100-day old plants of Alyssum . Results Results showed that the concentration of Ni in xylem sap of various Alyssum genotypes was 10–100 fold higher than the concentration of histidine, malate, citrate, and nicotianamine, which were the predominant Ni ligands measured in the sap. Conclusion When the physiology of the whole plant is taken into account, our results indicate that the concentration of organic chelators is too low to account for the complexation of all the Ni present in the xylem sap of Alyssum at steady-state Ni hyperaccumulation, and suggest that most of the Ni in xylem sap of this species is present as the hydrated cation.

  • Xylem exudate composition and root-to-shoot nickel translocation in Alyssum species
    Plant and Soil, 2013
    Co-Authors: Tiziana Centofanti, Zehra Sayers, Maria Isabel Cabello-conejo, Petra Kidd, Naoko K. Nishizawa, Yusuke Kakei, Allen P. Davis, Richard C. Sicher, Rufus L Chaney
    Abstract:

    An improved understanding of the Ni root-to-shoot translocation mechanism in hyperaccumulators is necessary to increase Ni uptake efficiency for phytoextraction technologies. It has been presumed that an important aspect of Ni translocation and storage involves chelation with organic ligands. It has been reported that exposing several Ni hyperaccumulator species of Alyssum to Ni elicited a large increase in the histidine level of the xylem sap. In later studies it was shown that as time progressed the histidine:Ni ratio dropped considerably. Moreover, previous studies analyzed the relationship between Ni and ligands in plants that were exposed to Ni only for a few hours and therefore obtained results that are unlikely to represent field soils where plants are at steady-state Ni uptake. The aim of this study was to understand the quantitative relationship between Ni and organic ligands in the xylem sap of various Alyssum genotypes or species that reached steady-state Ni uptake after being exposed to Ni in either nutrient solution or serpentine soil for up to 6 weeks. Total Ni concentration, 17 amino acids, 9 organic acids, and nicotianamine were measured in xylem sap of 100-day old plants of Alyssum. Results showed that the concentration of Ni in xylem sap of various Alyssum genotypes was 10-100 fold higher than the concentration of histidine, malate, citrate, and nicotianamine, which were the predominant Ni ligands measured in the sap. When the physiology of the whole plant is taken into account, our results indicate that the concentration of organic chelators is too low to account for the complexation of all the Ni present in the xylem sap of Alyssum at steady-state Ni hyperaccumulation, and suggest that most of the Ni in xylem sap of this species is present as the hydrated cation

  • EVALUATION OF PLANT GROWTH REGULATORS TO INCREASE NICKEL PHYTOEXTRACTION BY Alyssum SPECIES
    International journal of phytoremediation, 2012
    Co-Authors: M. I. Cabello-conejo, Tiziana Centofanti, Petra S. Kidd, Ángeles Prieto-fernández, Rufus L Chaney
    Abstract:

    Recent studies have shown that application of phytohormones to shoots of Alyssum murale increased biomass production but did not increase Ni shoot concentration. Increased biomass and Ni phytoextraction efficiency is useful to achieve economically viable phytomining. The objective of this study was to evaluate the effect of two types of phytohormones on the Ni phytoextraction capacity of four Alyssum species. Two different commercially available phytohormones (Cytokin® and Promalin®) based on cytokinins and/or gibberellins were applied on shoot biomass of four Ni hyperaccumulating Alyssum species (A. corsicum, A. malacitanum, A. murale, and A. pintodasilvae). Cytokin was applied in two concentrations and promalin in one concentration. The application of phytohormones had no clear positive effect on biomass production, Ni accumulation and Ni phytoextraction efficiency in the studied Alyssum species. A. malacitanum was the only species in which a significantly negative effect of these treatments was observe...

  • Interaction of nickel and manganese in accumulation and localization in leaves of the Ni hyperaccumulators Alyssum murale and Alyssum corsicum
    Plant and Soil, 2009
    Co-Authors: C. Leigh Broadhurst, Timothy K Maugel, Eric F Erbe, Ryan V. Tappero, Donald L. Sparks, Rufus L Chaney
    Abstract:

    The genus Alyssum contains >50 Ni hyperaccumulator species; many can achieve >2.5% Ni in dry leaf. In soils with normal Mn levels, Alyssum trichome bases were previously observed to accumulate Ni and Mn to high levels. Here we report concentration and localization patterns in A. murale and A. corsicum grown in soils with nonphytotoxic factorial additions of Ni and Mn salts. Four leaf type subsets based on size and age accumulated Ni and Mn similarly. The greatest Mn accumulation (10 times control) was observed in A. corsicum with 40 mmol Mn kg^−1 and 40 mmol Ni kg^−1 added to potting soil. Whole leaf Ni concentrations decreased as Mn increased. Synchrotron X-ray fluorescence mapping of whole fresh leaves showed localized in distinct high-concentration Mn spots associated with trichomes, Ni and Mn distributions were strongly spatially correlated. Standard X-ray fluorescence point analysis/mapping of cryofractured and freeze-dried samples found that Ni and Mn were co-located and strongly concentrated only in trichome bases and in cells adjacent to trichomes. Nickel concentration was also strongly spatially correlated with sulfur. Results indicate that maximum Ni phytoextraction by Alyssum may be reduced in soils with higher phytoavailable Mn, and suggest that Ni hyperaccumulation in Alyssum species may have developed from a Mn handling system.

Alan J. M. Baker - One of the best experts on this subject based on the ideXlab platform.

  • simultaneous determination of organic acids and nitrate in xylem saps of the hyperaccumulator Alyssum murale by rp hplc after solid phase extraction with nanosized hydroxyapatite
    Journal of Chromatographic Science, 2010
    Co-Authors: Alan J. M. Baker, Wei Wei, Zhenggui Wei, Yaodong Wang, Haiyan Zhao
    Abstract:

    An analytical approach based on solid-phase extraction (SPE) with nanosized hydroxyapatite and reversed-phase high performance liquid chromatography (RP-HPLC) for the simultaneous determination of organic acids (oxalic, malic, malonic, citric, and fumaric) and nitrate in xylem saps of the hyperaccumulator Alyssum murale is presented in this study. The optimum experimental conditions for the separation and determination of organic acids and nitrate are studied. The interference from nitrate on oxalic acid in RP-HPLC is eliminated by SPE with nanosized hydroxyapatite, and the simultaneous determination of organic acids and nitrate is achieved by RP-HPLC at the optimum chromatographic conditions. The accuracy of the method is confirmed with an average recovery ranging between 95.2% and 99.8%, the relative standard deviations (RSD) are less than 2.0%. This method is successfully applied to determine the organic acids and nitrate in xylem saps of the hyperaccumulator Alyssum murale.

  • Effects of calcium on nickel tolerance and accumulation in Alyssum species and cabbage grown in nutrient solution
    Plant and Soil, 2008
    Co-Authors: Rufus L Chaney, Kuang-yu Chen, J. Scott Angle, Alan J. M. Baker
    Abstract:

    Nickel (Ni) phytoextraction using hyperaccumulator plant species to accumulate Ni from mineralized and contaminated soils rich in Ni is undergoing commercial development. Serpentinite derived soils have a very low ratio of Ca/Mg among soils due the nature of the parent rock. In crop plants, soil Ca reduces Ni uptake and phytotoxicity, so it is possible that the low Ca of serpentine soils could limit hyperaccumulator plant tolerance of serpentine soils used for commercial phytomining. In this study, we investigated the effects of varied Ca concentration in the presence of high Mg characteristic of serpentine soils on Ni uptake and tolerance by serpentine-endemic species Alyssum murale Waldst. et Kit. and A. pintodasilvae T.R. Dudley in comparison with cabbage (Brassica oleracea L. var. capita) in a nutrient solution study. The levels of Ca and Mg used were based on serpentine and normal soils, and Ni was based on achieving over 1% Ni in Alyssum shoots in preliminary tests. Varied solution concentrations of Ni (31.6–1,000 μM for Alyssum, 1.0–10 μM for cabbage) and Ca (0.128–5 mM) were used in a factorial experimental design; 2 mM Mg was used to mimic serpentine soils. Alyssum spp. showed much greater tolerance to high Ni, high Mg, and low Ca solution concentrations than cabbage. For Alyssum spp., Ni induced phytotoxicity was only apparent at 1,000 μM Ni with relatively low and high Ca/Mg quotient. In the 1,000 μM Ni treatment, shoot Ni concentrations ranged from 8.18 to 22.8 g kg−1 for A. murale and 7.60 to 16.0 g kg−1 for A. pintodasilvae. Normal solution Ca concentrations (0.8–2 mM) gave the best yield across all Ni treatments for the Alyssum species tested. It was clear that solution Ca levels affected shoot Ni concentration, shoot yield and Ni translocation from root to shoot, but the relation was non-linear, increasing with increasing Ca up to 2 mM Ca, then declining at the highest Ca. Our results indicate that Ca addition to high Mg serpentine soils with very low Ca/Mg ratio may reduce Ni phytotoxicity and improve annual Ni phytoextraction by Alyssum hyperaccumulator species. Removal of shoot biomass in phytomining will require Ca application to maintain full yield potential.

  • hyperaccumulation of nickel by two Alyssum species from the serpentine soils of iran
    Plant and Soil, 2007
    Co-Authors: Seyed Majid Ghaderian, Roger D Reeves, A Mohtadi, R Rahiminejad, Alan J. M. Baker
    Abstract:

    Serpentine soils, which contain relatively high concentrations of nickel and some other metals, are the preferred substrate for some plants, especially those that accumulate Ni in their tissues. In temperate regions more Ni-hyperaccumulator plants are found in Alyssum than in any other genus. In this study, serpentine soils of two areas (Marivan and Dizaj) in the west/northwest of Iran and also perennial Alyssum plants growing on these soils were analyzed for Ni and some other metals. The highest concentrations of total metals in the soils of these areas for Ni, Cr, Co and Mn were 1,350, 265, 94 and 1,150 μg g−1, respectively, while concentrations of Fe, Mg and Ca reached 3.55%, 16.8% and 0.585% respectively. The concentration of exchangeable Ni in these soils is up to 4.5 μg g−1. In this study two Alyssum species, A. inflatum and A. longistylum, have been collected from Marivan and Dizaj, respectively. Analysis of leaf dry matter shows that they can contain up to 3,700 and 8,100 μg Ni g−1, respectively. This is the first time that such high Ni concentrations have been found in these species. The concentrations of other metals determined in these species were in the normal range for serpentine plants, except for Ca, which was higher, up to 5.3% and 3.5%, respectively

  • Nickel and other metal uptake and accumulation by species of Alyssum (Brassicaceae) from the ultramafics of Iran
    Environmental pollution (Barking Essex : 1987), 2006
    Co-Authors: Seyed Majid Ghaderian, A Mohtadi, Mohammad Reza Rahiminejad, Alan J. M. Baker
    Abstract:

    Abstract Some plants growing on serpentine (ultramafic) soils are able to hyperaccumulate nickel in their above-ground parts. The genus Alyssum L. contains the greatest number of Ni-hyperaccumulator plants so far reported. There are substantial areas of serpentine soils at many locations in Iran. This paper presents the analyses for Ni, Cr, Mn, Fe, Mg and Ca in soils and Alyssum species from the ultramafics of west and northwest Iran. Soil analysis for total elements in these areas indicates that typical concentrations of Ni, Cr, Mn, Fe, Mg and Ca are up to about 1240, 365, 800, 51,150, 152,390 and 11,790 μg g−1, respectively. During this study, seven Alyssum species were collected. Analysis of leaf dry matter shows that Alyssum bracteatum can contain up to 2300 μg Ni g−1, while the other species contain much lower concentrations of Ni and other elements. A. bracteatum is endemic to Iran and the first Ni hyperaccumulator reported from this species.

  • free histidine as a metal chelator in plants that accumulate nickel
    Nature, 1996
    Co-Authors: Ute Kramer, Alan J. M. Baker, Janet D Cotterhowells, John M Charnock, Andrew J C Smith
    Abstract:

    A NUMBER of terrestrial plants accumulate large quantities of metals such as zinc, manganese, nickel, cobalt and copper in their shoots1. The largest group of these so-called 'metal hyperaccumulators' is found in the genus Alyssum, in which nickel concentrations can reach 3% of leaf dry biomass2,3. Apart from their intrinsic interest, plants exhibiting this trait could be of value in the decontamination of metal-polluted soils4–6. However, the biochemical basis of the capacity for metal accumulation has not been elucidated. Here we report that exposing hyperaccumu-lator species of Alyssum to nickel elicits a large and proportional increase in the levels of free histidine, which is shown to be coordinated with nickel in vivo. Moreover, supplying histidine to a non-accumulating species greatly increases both its nickel tolerance and capacity for nickel transport to the shoot, indicating that enhanced production of histidine is responsible for the nickel hyperaccumulation phenotype in Alyssum.

Stephen D. Wratten - One of the best experts on this subject based on the ideXlab platform.

  • Flowering Alyssum (Lobularia maritima) promote arthropod diversity and biological control of Myzus persicae
    Journal of Asia-Pacific Entomology, 2020
    Co-Authors: Sundar Tiwari, Sheela Sharma, Stephen D. Wratten
    Abstract:

    Abstract Radish, Raphanus sativus is an important vegetable crop worldwide. It is the second most important vegetable after cabbage and cauliflower in winter (January to March) in Nepal. This crop is damaged by various herbivores such as the green peach aphid, Myzus persicae, the soybean hairy caterpillar, Spilarctia casigneta and the flea beetle, Monolepta signata. Prophylactic pesticide use is a part of the common pest management practice in Nepal. The candidate floral plant, Alyssum, Lobularia maritima, was deployed in a radish field to improve pest biological control. Beneficial arthropods trapped such as Syrphidae, Coccinellidae, Carabidae, Staphylinidae, Formicidae, Lycosidae, Apidae and Ichneumonidae were significantly more abundant in flowering Alyssum plots than the control (non-flowering) plots. Flowering Alyssum in radish fields significantly increases the population of observed syrphids (larva and adult). Similarly observed ladybirds was slightly higher in flowering plot compared with control plot however that was not significant. These beneficial predators potentially increase the biological control of M. persicae. These results provide evidence of the Alyssum’s ability to increase the abundance of predators and support the suppression of M. persicae in radishes. This study is useful in developing an integrated pest management protocol by integrating flowering strips in radish fields. Habitat manipulation in radish fields by maintaining flower strips can improve pest biological control and support the provision of multiple ecosystem services that restore diminished ecosystem functions in agriculture.

  • host plant selection by the wheat bug nysius huttoni hemiptera lygaeidae on a range of potential trap plant species
    Journal of Economic Entomology, 2018
    Co-Authors: Sundar Tiwari, Nicholas M Dickinson, David J Saville, Stephen D. Wratten
    Abstract:

    The wheat bug, Nysius huttoni L. is an endemic New Zealand pest. The seedlings of forage brassicas are highly susceptible to direct feeding damage by this insect, and this can reduce plant establishment. Prophylactic use of pesticides is the usual practice for N. huttoni management. These practices have been linked to environmental pollution, biodiversity loss, and pollinator population declines in brassicas and other crops. Habitat management of the bug utilizing potential trap crops can be a better option for its management. A series of choice, no-choice, and paired-choice tests were conducted in a controlled-temperature room to evaluate the pest’s preferences on seedlings of eight plant species. Kale plants (Brassica oleracea) were used as a potentially susceptible control, and seven non-kale plants were compared with kale as potential trap-plant species. These were: Lobularia maritima (L.) Desvaux (Alyssum), Triticum aestivum L. (wheat), Phacelia tanacetifolia Bentham (phacelia), Fagopyrum esculentum Moench (buckwheat), Coriandrum sativum L. (coriander), Trifolium repens L. (white clover), and Medicago sativa L. (lucerne). In choice tests, wheat was the most suitable followed by Alyssum, buckwheat, and phacelia, all significantly more favored than kale. In no-choice tests, Alyssum was significantly more favored than kale and the other plant species except wheat and phacelia. First feeding damage was recorded on Alyssum in both the above test conditions. For paired-choice tests including kale, wheat, and Alyssum were significantly more suitable than brassica. These findings are important for developing agro-ecological management strategies. Alyssum followed by wheat were the most suitable trap plants for N. huttoni. These two plant species can be deployed in and around brassica fields either independently or as in a multiple trap-cropping system to reduce bug damage, minimizing or avoiding pesticides, and delivering a range of ecosystem services.

  • host plant selection by the wheat bug nysius huttoni hemiptera lygaeidae on a range of potential trap plant species
    New Zealand Plant Protection, 2017
    Co-Authors: Sundar Tiwari, Nicholas M Dickinson, David J Saville, Stephen D. Wratten
    Abstract:

    Nysius huttoni is an endemic New Zealand insect pest. Its feeding can seriously reduce crop establishment in forage brassicas. A series of choice, no-choice and paired-choice tests were conducted in a controlled- temperature room to evaluate the pest’s host preferences on seedlings of eight plant species: Lobularia maritima (Alyssum), Triticum aestivum (wheat), Phacelia tanacetifolia (phacelia), Fagopyrum esculentum (buckwheat), Coriandrum sativum (coriander), Trifolium repens (white clover) and Medicago sativa (alfalfa), and Brassica oleracea (kale) as a potentially susceptible control. In choice tests, wheat was the most preferred followed by Alyssum, buckwheat and phacelia, all being signi cantly more favoured than kale. Survival rate of wheat bugs over 120 h was: on phacelia (71.0%), clover (69.0%), Alyssum (48.0%) and wheat (47%), which were all signi cantly higher than on kale seedlings. Alyssum and wheat were more susceptible to N. huttoni feeding damage than were other tested plants. High survival rates were recorded in paired choice tests on kale and Alyssum (78.3%) compared with the other paired choice tests. The implications of these ndings are important for developing ecological management strategies in, or around, forage brassica elds.

  • floral nectar affects longevity of the aphid parasitoid aphidius ervi and its hyperparasitoid dendrocerus aphidum
    New Zealand Plant Protection, 2006
    Co-Authors: Salaheddin Araj, Stephen D. Wratten, Hannah L Buckley
    Abstract:

    In this study, the potential consequences of making a three- or four-trophic level system more complex by adding floral resources was studied in the laboratory for a range of plant nectar sources, the aphid parasitoid Aphidius ervi and its hyperparasitoid Dendrocerus aphidum. Parasitoids exposed to flowering buckwheat survived 4-5 times longer than those in the control (water only) and 3-4 times longer than those provided with phacelia, Alyssum or coriander. Hyperarasitoids provided with buckwheat survived 5–6 times longer than those in the control and 3-5 times longer than those on the other flowering plants. Buckwheat, phacelia, Alyssum and coriander can therefore enhance the ‘fitness’ of A. ervi without benefiting its aphid host, which does not feed on nectar. However, the ‘fitness’ of the hyperparasitoid may increase relatively more than that of the parasitoid, depending on the nectar source.

  • the effects of floral understoreys on parasitism of leafrollers lepidoptera tortricidae on apples in new zealand
    Agricultural and Forest Entomology, 2006
    Co-Authors: N A Irvin, S L Scarratt, R B Chapman, Stephen D. Wratten, Christopher M. Frampton, Jason M. Tylianakis
    Abstract:

    Field and laboratory experiments on the conservation biocontrol of lepidop- teran leafroller pests were carried out in apples at Lincoln, New Zealand. 2 Apple understoreys were planted with replicated treatments of Alyssum (Lobularia maritima), phacelia (Phacelia tanacetifolia) and buckwheat (Fagopyrum esculentum). 3 Rates of parasitism of experimentally released larvae of the light-brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), by Dolichogenidea tasmanica (Cameron) (Hymenoptera: Braconidae) were signifi- cantly lower in phacelia and control treatments, and leafroller pupae were significantly more abundant in controls than in buckwheat and Alyssum treatments. 4 Naturally occurring leafroller damage was up to 29% lower above all the floral understorey treatments compared with controls and there were more than twice as many D. tasmanica cocoons in the Alyssum and buckwheat treatments than in controls. 5 Suction sampling of the understoreys gave D. tasmanica adult densities that were significantly more abundant in Alyssum compared with other treatments. Numbers of Anacharis zealandica (Hymenoptera: Figitidae) (a parasitoid of larvae of the predatory brown lacewing) did not differ between treatments. 6 In the laboratory, flowering buckwheat and Alyssum enhanced D. tasmanica longevity by up to 78% compared with the control, and buckwheat also enhanced potential fecundity by 62%. 7 In choice experiments, leafroller larvae in the laboratory consumed more than three-fold more apple leaf material than they did of the three understorey species, although Alyssum increased leafroller fecundity and longevity. 8 The use of floral understoreys for conservation biocontrol of apple pests is discussed, along with the potential negative effects of some flowering species on pest populations and orchard agronomic practices.

Richard J. Roseberg - One of the best experts on this subject based on the ideXlab platform.

  • The effect of pH on metal accumulation in two Alyssum species.
    Journal of environmental quality, 2004
    Co-Authors: Urszula Kukier, Rufus L Chaney, J. Scott Angle, Carinne A. Peters, Richard J. Roseberg
    Abstract:

    Nickel phytoextraction using hyperaccumulator plants offers a potential for profit while decontaminating soils. Although soil pH is considered a key factor in metal uptake by crops, little is known about soil pH effects on metal uptake by hyperaccumulator plants. Two Ni and Co hyperaccumulators, Alyssum murale and A. corsicum, were grown in Quarry muck (Terric Haplohemist) and Welland (Typic Epiaquoll) soils contaminated by a Ni refinery in Port Colborne, Ontario, Canada, and in the serpentine Brockman soil (Typic Xerochrepts) from Oregon, USA. Soils were acidified and limed to cover pH from strongly acidic to mildly alkaline. Alyssum grown in both industrially contaminated soils exhibited increased Ni concentration in shoots as soil pH increased despite a decrease in water-soluble soil Ni, opposite to that seen with agricultural crop plants. A small decrease in Alyssum shoot Ni concentration as soil pH increased was observed in the serpentine soil. The highest fraction of total soil Ni was phytoextracted from Quarry muck (6.3%), followed by Welland (4.7%), and Brockman (0.84%). Maximum Ni phytoextraction was achieved at pH 7.3, 7.7, and 6.4 in the Quarry, Welland, and Brockman soils, respectively. Cobalt concentrations in shoots increased with soil pH increase in the Quarry muck, but decreased in the Welland soil. Plants extracted 1.71, 0.83, and 0.05% of the total soil Co from Welland, Quarry, and Brockman, respectively. The differences in uptake pattern of Ni and Co by Alyssum from different soils and pH were probably related to the differences in organic matter and iron contents of the soils.

Nermin Orcan - One of the best experts on this subject based on the ideXlab platform.