Antony Van der Ent

Wageningen University & Research | WUR · Laboratory of Genetics

Crotalaria is a genus of ~600 species of legumes predominantly found in (sub)tropical regions of Africa and Australia. Crotalaria novae‐hollandiae from Australia is a polymetallic zinc (Zn)‐cadmium(Cd)‐copper(Cu) hyperaccumulator, but only when growing in metalliferous soils. This study aimed to test metal tolerance in Australian Crotalaria species...

Accurately determining the elemental composition of plant tissues is essential for physiological studies on plant stress, including salinity tolerance. However, high-throughput routine analysis of light elements (range of sodium to calcium) in plant samples is challenging due to the need for complete sample dissolution and expensive inductively cou...

The 10th International Conference on Serpentine Ecology was held in Nancy, France on June 12–16, 2023. The main goals of the conference were to create a platform for the exchange of ideas and experiences and to promote scientific dialogue among scientists from numerous fields who share expertise in the study of ultramafic habitats worldwide. The pr...

We assessed the effects of soil type on the concentrations of seven elements (calcium, potassium, sulfur, phosphorus, iron, manganese, zinc) in plants using x‐ray fluorescence (XRF) analysis and plant specimens collected from calcareous and ultramafic soil areas, and ‘general soils’ (other types of soil represented by Brown Forest soils and Andosol...

Background and aims Odontarrhena chalcidica is a well-known nickel hyperaccumulator which also take up zinc efficiently, but little is known regarding its zinc uptake mechanisms. Therefore, this study compared the uptake kinetics of zinc and nickel. Methods Plants were cultivated under various metals (nickel, zinc, cobalt and iron) concentrations...

The discovery of the nickel-rich latex of the New Caledonian endemic tree Pycnandra acuminata introduced the term 'hyperaccumulator' and gave rise to a new field of research. This then instigated a global quest for these unusual hyperaccumulator plants, even while the underlying mechanisms of nickel acquisition, transport, and internal elemental di...

Thallium is the most toxic element known to mankind and an emerging environmental contaminant of concern. Thallium is not only toxic, but also economically valuable, and therefore novel methods for extraction from contaminated land or wastes are desirable, including phytomining using hyperaccumulator plants. Facultative hyperaccumulation is a ra...

Background and aims Thallium (Tl) is extremely toxic to all lifeforms and an emerging pollutant. Plants in the Brassicaceae family, including edible crops, have an enhanced capacity for Tl accumulation, even from soils with low thallium concentration. The most extreme Tl hyperaccumulator is Biscutella laevigata, capable of attaining >32,000 μg Tl g...

Nickel is a crucial metal widely used in various industrial applications, such as lithium‐ion batteries and stainless‐steel production. The increasing demand for nickel and resource depletion challenges highlight the need for sustainable extraction methods. Agromining employs hyperaccumulator plants to extract nickel from soils that are either cont...

The 10th International Conference on Serpentine Ecology was held in Nancy, France on 12-16 June, 2023. As a major international scientific forum in the field of serpentine (ultramafic) ecology, this conference brings together botanists , zoologists, microbiologists, physiologists, geneticists, geologists, soil scientists , and other applied special...

Research on metal hyperaccumulating plants has concentrated on New Caledonia, Brazil, Cuba, the Mediterranean basin, and southeastern Asia, while other regions remain under studied. This work used a systematic approach in the targeted search for new hyperaccumulators in Mesoamerica, with a focus on characterizing nickel (Ni) hyperaccumulation in si...

Andosols are characterized by relatively high sulfur concentrations, but also by their low phosphorus availability for crops and vegetables. We assessed the effect of soil type on the concentrations of sulfur and phosphorus in plants using handheld X-ray fluorescence (XRF) analysis on herbarium specimens collected from Andosols and non-volcanic soi...

The use of x‐ray fluorescence (XRF) instruments for metallome analysis of herbarium specimens to discover hyperaccumulator plant species has gained popularity, but a growing concern arises about intercomparability from the use of different instrument makes and models. Therefore, this study aimed to assess the performance and comparability of the re...

Background and Aims The tropical shrub Coelospermum decipiens (Rubiaceae) is an extreme selenium (Se) hyperaccumulator, reported to accumulate up to 1140 µg Se g−1 when found growing on soils with levels of Se below the limit of detection (i.e. <0.01 mg Se kg−1) leading to a bioconcentration factor of >100 000. Methods Coelospermum decipiens plant...

Background and aims The nickel hyperaccumulator Bornmuellera emarginata (Brassicaceae) is a species adapted to thrive on naturally nickel-enriched ultramafic soils in the Balkans and a promising candidate for use in nickel agromining. The main aim of this study was to provide insight into the physiological mechanisms of nickel hyperaccumulation in...

Until 2019, there were no published reports of trace element hyperaccumulation in the plants of Central America or Mexico. Recent reports, based mostly on measurement of herbarium specimens using x‐ray fluorescence (XRF) spectroscopy, have begun to identify hyperaccumulators of nickel (Ni) in this region. The most extensive deposits of Ni‐rich ultr...

Background and Aims Indonesia is one of the most biodiverse regions in the world, but only a few metal hyperaccumulator plants have been reported from this vast country. This study aimed to discover rare earth element (REE) hyperaccumulator plants on Bangka Island, an area known to have REE enriched soils associated with tin placer deposits. Metho...

Self-sustaining vegetation in metal-contaminated areas is essential for rebuilding the ecological resilience and community stability in degraded lands. Metal-tolerant plants originating from contaminated post-mining areas may hold the key to successful plant establishment and growth. Yet, little is known about the impact of metal toxicity on reprod...

Noccaea praecox and Noccaea caerulescens (Brassicaceae) are nickel and zinc hyperaccumulators, native to Europe. To date, most studies have focused on metal accumulation in the leaves, whereas the distribution of metals in the inflorescences of hyperaccumulator plants remains largely unexplored, but of great interest in the context of adaptation to...

The global energy transition from fossil fuels to renewable sources poses substantial challenges to increase metal production, including industry-critical rare earth elements (REEs). Environmental and social concerns obfuscate the production of these 'green' metals and only ~1% of REE demand is met from recycling. This work highlights the potential...

Background and aims The Richmond District of Queensland (Australia) hosts seleniferous soils and is the habitat of selenium (Se) hyperaccumulator plants. These soils are also naturally enriched in vanadium (V) and molybdenum (Mo). This study aimed to survey soils and plants of the Richmond area with a focus on the Se hyperaccumulator Neptunia ample...

Background and aims Nickel (Ni) deficiency has been reported to occur in soybean (Glycine max) grown on leached tropical soils in Brazil. We aimed to determine whether an internal or external Ni supply can compensate for low Ni within the seed by assessing whether the amount of Ni in the seed whether the foliar-application of aqueous NiSO4 influenc...

Odontarrhena muralis (Brassicaceae) is a nickel hyperaccumulator species from the Balkans used as a “metal crop” in nickel phytomining. This study aimed to determine the elemental distribution, focusing on nickel, in fresh-hydrated plant tissue (stems, leaves and inflorescences), to clarify where nickel is localized at the tissue and cellular scale...

Background When studying metallophytes and hyperaccumulator plants, it is often desired to assess the level of tolerance of a specific trace metal/metalloid in a putative tolerant species, to determine root and shoot accumulation of the trace metal/metalloid of interest, or to establish whether a trace metal/metalloid has an essential function. The...

Toxic metals and metalloids, especially from anthropogenic sources, now pollute substantial areas of our planet. Phytoextraction is a proven technology with the potential to reduce metal/metalloid pollution, and where financially viable, recover valuable metals (‘phytomining’). Toward these aims, there has been a surge of publications over the last...

This cover in Environmental Science & Technology is out now. It shows thallium distribution (green) in a leaf of Brassica oleracea: some varieties have an extraordinary capacity to accumulate thallium from low concentrations in soil or nutrient solution.

X-ray fluorescence spectroscopy (XRF) is a relatively new method for non-destructive elemental analysis of herbarium material that meets the scientific interest in being capable of discovering new hyperaccumulator plant species. Since the genus Noccaea (Brassicaceae family) is known to be one of the most numerous in term of the hyperaccumulator pla...

Context Rare earth elements (REEs) are increasingly crucial for modern technologies. Plants could be used as a biogeochemical pathfinder and a tool to extract REEs from deposits. However, a paucity of information on suitable plants for these tasks exists. Methods We aimed to discover new REE (hyper)accumulating plant species by performing an X-ray...

The known manganese (Mn) hyperaccumulator Gossia bidwillii, and G. acmenoides unknown to hyperaccumulate Mn are tree species native to subtropical eastern Australia, where they co-occur on Mn-rich soils. Here, we investigate Mn accumulation and distribution in G. acmenoides collected from its natural habitat, and propagated G. bidwillii plants in a...

Extraction and processing of disseminated metalliferous ores, porphyry copper in particular, results in significant tonnages of waste and can cause severe disturbances and contamination in natural ecosystems. This is particularly important in semi-arid climates where natural soils are often deprived of organic matter and nutrients. This study was c...

An increasing number of studies have shown how feedback interactions between plants and soil can influence primary and secondary succession. However, very little is known about the patterns and mechanisms of such plant–soil feedbacks on stressed mine tailings ecosystem, which can be severely contaminated by a range of toxic elements. In a two‐phase...

The biogeochemical cycling of mercury (Hg) is an important topic of study due to the health implications of the release of this toxic element in the environment. Tropical ecosystems have been understudied, and examining elevational gradients can provide insights into mechanisms controlling soil Hg concentrations. The aim of this study was to determ...

The abandoned Allchar Mine in the Republic of North Macedonia is a globally unique deposit with historical tailings from processing ore containing extremely toxic metal(loid)s concentrations, with up to 76.1 g kg−1 and 6.5 g kg−1 of As and Tl, respectively. Five pseudo-metallophyte species which naturally colonise the Allchar tailings were sampled:...

The abandoned Allchar Mine in the Republic of North Macedonia is a globally unique deposit with the highest known grades of thallium (Tl) and arsenic (As) mineralisation. We aimed to determine the distribution of As and Tl in whole dehydrated shoots of the three Viola taxa using synchrotron μXRF analysis. Additionally, soil and plant organ samples...

Extraction and processing of metalliferous ores can cause severe disturbances and contamination in natural ecosystems but little known about such effects for copper mines in semi-arid areas of southwest Asia. This study was conducted on seven sites around Sungun Copper Mine area, northwest Iran. Electrical Conductivity (EC), pH, nitrogen, phosphoro...

Background and aims Hyperaccumulation is generally defined as plants exhibiting concentrations of metal(loid)s in their shoots at least an order of magnitude higher than that found in ‘normal’ plants, but this notional threshold appears to have limited statistical underpinning. The advent of massive (handheld) X-ray fluorescence datasets of herbari...

Background and aims An innovative approach “Herbarium Ionomics” used a handheld X-ray fluorescence (XRF) device to non-destructively extract quantitative elemental data (i.e. , the metallome) from herbarium specimens. This has led to the discovery of numerous hyperaccumulator plants. Once a new hyperaccumulator is identified through XRF screening,...

Background and aims: Selenium hyperaccumulator species are of primary interest for studying the evolution of hyperaccumulation and biofortification as selenium is an essential element in human nutrition. We aimed to determine whether the distributions of selenium in Astragalus bisulcatus, Stanleya pinnata and Neptunia amplexicaulis are similar or...

Synchrotron-based micro-X-ray fluorescence analysis (µXRF) is a non-destructive and highly sensitive technique. However, element mapping of rare earth elements (REEs) under standard conditions requires care, since energy-dispersive detectors are not able to differentiate accurately between REEs L-shell X-ray emission lines overlapping with K-shell...

Pityrogramma calomelanos and Pteris vittata are cosmopolitan fern species that are the strongest known arsenic (As) hyperaccumulators, with potential to be used in the remediation of arsenic-contaminated mine tailings. However, it is currently unknown what chemical processes lead to uptake of As in the roots. This information is critical to identif...

Aims Phosphorus (P) deficiency-induced mobilization of rare earth elements (REEs) in the rhizosphere contributes to REE accumulation in the hyperaccumulator Phytolacca americana, but a lack of in situ methods for visualization of the root-soil interface limits our understanding of the underlying processes. Methods Diffusive gradients in thin-films...

Main conclusion The VNIR reflectance spectra of nickel hyperaccumulator plant leaves have spectral variations due to high nickel concentrations and this property could potentially be used for discovery of these plants. Abstract Hyperaccumulator plants accumulate high concentrations of certain metals, including manganese, cobalt, or nickel. Of the...

Context Fewer than 10 plant species from Australia were known to hyperaccumulate metal(loid)s, despite metal-rich soils being widespread in Australia. By measuring herbarium specimens with non-destructive portable X-ray fluorescence spectroscopy (XRF) instrumentation their metal(loid)s concentrations can be determined, providing information that co...

Background and aims Hyperaccumulator plants exhibit extreme ecophysiological characteristics, which make them suited for phytoremediation. Understanding their ecological strategies might help identify the species and functions to be favored in phytoremediation, restoration, and conservation projects for metalliferous sites. Methods Here, we identi...

Rare earth elements (REEs) are critical for numerous modern technologies, and demand is increasing globally; however, production steps are resource-intensive and environmentally damaging. Some plant species are able to hyperaccumulate REEs, and understanding the biology behind this phenomenon could play a pivotal role in developing more environment...

X-ray Fluorescence Spectroscopy (XRF) is a non-destructive analytical technique that has recently been developed as a tool for high throughput screening for the discovery of trace element hyperaccumulator species in herbarium collections. Herbarium XRF analysis was undertaken of representatives of the Brassicaceae family in the two herbaria in Belg...

Context Root foraging by hyperaccumulator plants in response to patchily distributed metals has been observed in several obligate hyperaccumulators, but it is not known whether facultative hyperaccumulators respond similarly. Aims This study investigated the root-growth behaviour in the leguminous zinc (Zn) hyperaccumulator Crotalaria novae-holland...

Lithium (Li), gallium (Ga) and indium (In) are industry-critical metals, with no known plant species that (hyper)accumulate these metals to any substantial degree. We hypothesised that sodium (Na) hyperaccumulators (i.e., halophytes) may accumulate Li, whilst aluminium (Al) hyperaccumulators may accumulate Ga and In, based on the chemical similarit...

Dicranopteris linearis is the best-known hyperaccumulator species of rare earth elements (REEs) and silicon (Si), capable of dealing with toxic level of REEs. Hence, this study aimed to clarify how D. linearis leaves cope with excessive REE stress, and whether Si plays a role in REE detoxification. The results show that lanthanum (La – as a represe...

Background: “Herbarium X-ray Fluorescence (XRF) Ionomics” is a new quantitative approach for extracting the elemental concentrations from herbarium specimens using handheld XRF devices. These instruments are principally designed for dense sample material of infinite thickness (such as rock or soil powder), and their built-in algorithms and factory...

Background and aims Proteaceae species strongly acidify their rhizosphere to increase soil phosphorus (P) availability, which also inadvertently increases the availability of other elements, such as manganese and rare earth elements (REE). This study aimed to investigate REE (hyper) accumulation in the Proteaceae genus Helicia from Queensland, Aust...

Neptunia amplexicaulis is an herbaceous legume endemic to the Richmond area in central Queensland, Australia and is one of the strongest known Selenium hyperaccumulators on earth, showing significant potential to be utilised in Se phytoextraction applications. Here a protocol was established for in vitro micropropagation of Se hyperaccumulator N. a...

Main conclusion Micro-analytical techniques to untangle Se distribution and chemical speciation in plants coupled with molecular biology analysis enable the deciphering of metabolic pathways responsible for Se tolerance and accumulation. Abstract Selenium (Se) is not essential for plants and is toxic at high concentrations. However, Se hyperaccumu...

The 10th International Conference on Serpentine Ecology will take place in Nancy, France on 12–16 June 2023. It is the major international scientific forum for anyone interested in all aspects of serpentine (ultramafic) ecosystems worldwide. Please visit the conference website: https://icse2023.sciencesconf.org/

Background and aims: While isotopic enrichment of nitrogen ( 15N) and carbon ( 13C) is often used to determine whether carnivorous plant species capture and assimilate nutrients from supplemental sources such as invertebrate prey or mammal excreta (heterotrophic nutrition), little is known about how successful the different strategies deployed by...

Hyperaccumulator plants are able to tolerate extremely high concentrations of metals/metalloids in the soil in which they grow and to accumulate high concentrations in their shoots. To date, a total of 31 hyperaccumulator plant species have been identified in the Balkans, the centre of diversity and speciation in the European flora which is parti...

The increasing demand for Rare Earth Elements (REEs) and the depletion of mineral resources motivates sustainable strategies for REE recovery from alternative unconventional sources, such as REE hyperaccumulator. The greatest impediment to REE agromining is the difficulty in the separation of REEs and other elements from the harvested biomass (bio-...

Visualising the endogenous distribution of elements within plant organs affords key insights in the regulation of trace elements in plants. Hyperaccumulators have extreme metal(loid) concentrations in their tissues which make them useful models for studying metal(loid) homeostasis in plants. X-ray based methods allow for the non-destructive analysi...

Purpose Thallium (Tl) is one of the most toxic elements known and its contamination is an emerging environmental issue associated with base metal (zinc-lead) mining wastes. This study investigated the nature of Tl tolerance and accumulation in Silene latifolia, which has so far only been reported from field-collected samples. Methods Silene latifol...

Context. Hyperaccumulator plants are of considerable interest for their extreme physiology. Stackhousia tryonii is a nickel (Ni) hyperaccumulator plant endemic to ultramafic outcrops in Queensland (Australia) capable of attaining up to 41 300 μg g −1 foliar Ni. Aims. This study sought to elucidate the distribution of Ni in S. tryonii by using synch...

Purpose The increasing volumes of mine tailings that are being generated globally because of the rise in metal demand, whilst ore-grades continue to decline, call for novel sustainable management options. Phytoextraction using hyperaccumulator plant species may be one of such strategies to deal with these large volumes of contaminated materials. Ho...

The profiles of trace and major elements in three Odontarrhena species from the ultramafics of Western Iran (O. callichroa, O. penjwinensis and O. inflata) were evaluated to provide detailed information on their soil-plant relationships and potentials for agromining. The mean concentrations of Ni in leaf dry matter of these three species were 877,...

Aims Rare earth elements (REEs) and normalized REE patterns determined in plant and soil samples represent powerful tools to trace biogeochemical processes during weathering, soil genesis and processes in the rhizosphere, and thus publications reporting REE concentrations and normalized REE patterns in soil systems and plants are rapidly increasing...