st
14 - 16 June 2005 Pisa, Italy
Hosted by ISE-CNR - the National Research Council of Italy, Pisa, Italy
Plant uptake/exclusion and translocation of nutrients and contaminants
Session 1 (report by N. Lepp)
This session consisted of 4 oral presentations, each of 20 minutes duration.
1) Fangjie ZHAO (UK)
Phytoextraction of metals from contaminated soils: fact or fiction?
This presentation reviewed the current status of phytoextraction as a viable technology for removing metals from polluted soils. The significant increase in peer-reviewed publications dealing with phytoextraction was noted and a useful definition of the process was given. The requirements for a viable phytoextractor were discussed; a requirement for hyperaccumulation was considered of primary importance, but this was only considered useful for treating soils with moderate levels of metal contamination. It was also noted that Biological Concentration Factors (BCF’s) decreased as soil metal concentrations increased, indicating that plants did not possess the capacity for exponential metal uptake. The lack of a Cu hyperaccumulator was noted and the effect of me tal toxicity on BCF’s was carefully considered. Two widely cited publications on Pb hyperaccumulation were critically discussed; it was concluded that both were flawed and bore little relevance to real world situations. Problems relating to chelate-enhanced phytoextraction were also mentioned. It was concluded that phytoextraction may be applicable as a method for ‘polishing’ soils that just exceed statutory limits, but the technology had not been reliably demonstrated under field scale conditions. However, the associated phenomenon of hyperaccumulation was a biological problem well worth continuing investigation.
2) Simona Di GREGORIO (Italy)
Potential of application of non-ionic surfactants and plant growth promoting rhizobacteria on EDTA-assisted lead phytoextraction.
The effects of EDTA on roots were discussed and the low mobility of PbEDTA in plants was noted. Experiments were described where the aim was to

increase plant biomass by treatment with growth promoting rhizobacteria
(PGPR) (promote root growth by suppression of ethylene production) and to enhance mobility of PbEDTA by addition of a surfactant to Pb contaminated soil. A single growth promoting PGPR isolate was found and used in subsequent experiments. Microcosms were established with plants growing in Pb contaminated substrate with or without PGPR. EDTA and surfactants were added and plant Pb uptake measured. EDTA treatment increased Pb mobility, but this was not enhanced by the presence of a surfactant. EDTA reduced plant biomass production, but the presence of PGPR increased plant biomass in the presence of EDTA. Plants grown in this combination had a higher Pb content (μg g dry wt basis).
3) Morten LARSEN (Denmark)
Plant uptake of Iron cyanide complexes
This study looked at plant uptake of man-made Fe-cyanide complexes, produced during the manufacture of coal gas. These complexes break down to release ferri- and ferro-cyanides and free CN, the latter can be readily taken up by plants or may migrate to ground water. Uptake of the Fe complexes and CN was investigated using Willow ( Salix ) cuttings. Plants were grown in solution culture and any phytotoxic effects were assessed on the basis of changes in transpiration rate. There was no phytotoxicity observed.
Ferricyanide was the main species in solution and free CN decreased irrespective of the presence or absence of trees. Cyanide accumulated in roots and uptake was reduced in the presence of nitrate. Cyanide was not toxic to Salix and the transpiration-driven movement of CN into roots may prevent movement of CN to groundwater. This is currently being investigated in a field trial at the site of a former gas works.
4) Barbara IRTELLI (Italy)
Uptake kinetics of copper in Brassica carinata and role of amino acids in xylem sap transport.
This presentation reported on the use of a non-phytotoxic biodegradable chelating agent (EDDS) as a potential additive for chelate-assisted phytoextraction. This molecule degrades in soil within 28 days and has good stability constants with Cd, Cu, Pb and Zn. Brassica carinata was used as a test plant to investigate the effect of EDDS on Cu uptake in excised roots and whole plants. Uptake kinetics of Cu by excised roots changed in the presence of EDDS; in the absence of EDDS, uptake was biphasic, but when CuEEDS was present, Cu uptake could be described by simple Michaelis-Menten kinetics. This uptake pattern was evident across a range of CuEDDS concentrations, indicating that a different transporter was used for the Cu complex as opposed to free Cu ions. Copper forms complexes with amino acids in the xylem. Addition of Cu to nutrient solution resulted in an increase in total amino acids in xylem sap. Specific increases in glycine and aspartate were noted, but proline was considered to be the most important Cu-binding amino acid.

There was a lively question session following these presentations. One important point raised was the relationship of proline levels in plants to all forms of abiotic stress, which may have a bearing on the role of this amino acid in Cu binding.
Session 2 (report by R. Paul)
The session included three very different presentations, illustrating the wide range of subjects concerned by plant uptake/exclusion and translocation of nutrients and contaminants.
Chris Collins raised the question: “is it possible to predict the best plants for the phytoremediation”? How to choose the best plants from among several hundred thousand species? What could be the best basis for selection
(classical systematics, molecular based phylogenies, plant uptake analysis, and prediction tests.)?
Responses will also depend on what aspect of phytoremediation is to be considered: tolerance, uptake, and degradation, bioaccumulation in whole plants or just in edible parts.
Dieter Ernst discussed ascorbate promotion of emission of mercury vapour from barley grown in hydroponics. A model of phytoreduction of mercury in leaves was also proposed.
This work represents a theoretical contribution to our knowledge of the mercury cycle. No suggestions were made on how the phenomenon could be either increased or reduced. Several questions were asked about what would happen in vivo, with non-sterile substrates (soil direct volatilization without plant transfer?) and about BCF and accumulation sites in plants, but the study of these aspects were not the aims of the experiment.
Erika Nehnevajova’s presentation was, in contrast, based on extensive field experimentation. Sunflower mutants and cultivars were tested for their heavy metal bioaccumulation potential. High Cd, Zn, and Pb BCF’s were evident in some cases.
Cultivars seem to be more interesting to evaluate for phytoextraction potential than mutants, in the latter, increased BCF is often associated with decreased biomass production, at least for the first generation M1.
General discussion (report by P. Castro and G. Arapis)
During this session various presentations underlined the importance of the following scientific aspects, for which more discussion has been opened:
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Influence of Bioconcentration Factors (BCF) on phytoremediation technologies.

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Influence of plant biomass on the efficacy of phytotechnologies.
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How much BCF is dependent on the soil type, contaminant (concentration and chemical speciation), plant species and rhizosphere activity?
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At plant level: Better understanding of the translocation mechanism needed.
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How Laboratory studies will be extended to Field experiments and applications.
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What is the effect of multiple stressors in diverse ecosystems, including different environmental and agronomic conditions during a whole year?
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What is the role of plants tolerance and phytotoxicity?
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How we will apply EDTA and chelators from pot experiments to the field and to large areas.
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How to avoid underground water contamination.
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How to maintain soil fertility.
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How to minimize alteration of ecosystems and impact on the rhizosphere, when Microbial Ecology knowledge and techniques are used.
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How molecular based phylogenies can help for the selection of plants
(group-order-family, genus, species), in order to be used in phytotechnologies.
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Acceptability of GMO use in the environment.
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Acceptability of use of chemical mutagens (i.e. EMS) and of various mutant generations in phytotechnologies.
Some comments were made concerning the necessity to:
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Prevent soil quality, avoiding its contamination, before the development of rehabilitation phytotechnologies.
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Participate actively in the scientific aspects concerning the new EU Soil
Directive, for a sustainable land management.
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Promote the use of plants with low Transfer Factors, in order to improve food safety.
Exploiti ng the “-omics” approaches in phytotechnologies
Session 1 (report by A.R. Memon)
The applications of genomics, proteomics and metabolomics in the area of plant phytotechnologies have significant impact on European and international goals in environmental cleanup. No single plant displays all the necessary traits for efficient remediation of polluted soils and waters. Therefore,

developing new strategies to enhance the accumulation and tolerance of plants to toxic metals are necessary for delivering the long-term promise of phytotechnologies to promote sustainable land use and improve food safety.
The first session of Working Group 2 comprised four oral presentations.
Robert Edwards presented the data on applications for herbicide safeners in phytoremediation which were known long time ago to enhance the selectivity of herbicides in cereals. It has been shown that this enhancement includes a subtle re-programming of plant secondary metabolism and is not specific to cereal crops but can also be observed in other plants. The safener response in induction of detoxifying proteins and changes in secondary metabolism are plant species specific.
In the second presentation (Gabor Gullner), the detoxification mechanism of herbicides in wild type hybrid and transgenic poplar lines was described. The inducibility of ascorbate peroxidase (APOX) and glutathione-S- transferase
(GST) did not differ significantly between transgenic and wild type poplar lines but the exogenous sucrose supply enhanced the activities of both enzymes when poplar leaf discs were treated with paraquat and acetochlor herbicides.
Pierre Goloubinoff presented a multipurpose phyto-biological test for environmental stresses and organic pollutants using recombinant moss
Physcomitrella patens.
The objective of this research was to develop a range of sensitive plant biosensors that will be able to report mild changes in the plant cell homeostasis resulting from exposure to specific organic and chemical pollutants.
Glutathione and the enzymes in this pathway play a very important role in detoxifying metals in plants. Fabio Nocito showed that Cd exposure induces sulphate uptake in both maize and Indian mustard mainly up-regulating specific sulphate transporter genes. These data and the results of other groups clearly indicate the importance of glutathione and the enzymes in this pathway especially phytochelatin synthase in metal tolerance in plants.
Session 2 (report by D.M. Antosiewicz)
The discussion was focused on different approaches to find the molecular basis for metal hyperaccumulation and homeostasis.
It was agreed that the application of a variety of methods used for the identification of new genes involved in the process of metal hypertolerance / hyperaccumulation leads not only to overlaps (identification of the same genes) but also to cloning new sequences e.g. of unknown function, to be established in the course of a further study. Results overlap to a certain degree, but are also complementary. The comparison of the results indicates certain overlap, but also new sequences of unknown function detected.

When Gene Chips method is used e.g. Arabidopsis Gene Chips for comparative studies with A. thaliana and A. halleri roots, it is not known how higher level should be considered as significant difference that could indicate a possible role of the gene product in metal hyperaccumulation / homeostasis.
It is necessary to be aware that it could be very high, however, also a small increase may account for the change in the phenotype.
It has been pointed out that it is necessary to look not only for the transcript abundance but also for negative effects e.g. for down-regulated genes. Thus the important direction for future studies would be the detailed analysis of changes in the promoter sequence and function. Thus not only new genes should be identified but also those belonging to the same family; changed transcription profiles do suggest probable different regulation related to the plant response to the presence of metals in the environment; e.g. QTL elements enable to find both new genes and regulatory elements.
It was stressed out during the discussion that a plant response to metal ions depends on its age, therefore it is critical to consider the age when results are compared.
General discussion (report by N. Verbruggen and R. Carpena)

Robert Edwards presented the very interesting use of safeners to increase germination and growth of plants on oil-contaminated sites. Safeners seem to be able to transiently boost detoxification pathways, in particular in roots
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Gabor Gullner presented the use of transgenic gamma- ECS overexpressing transgenic lines of poplar to increase GST activity and possibly phytoremediation efficiency.
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Pierre Goloubinoff introduced Physcomittrella patens as a pollution biosensor. His project includes the use of Physcomittrella chip to identify specifically induced genes/ promoters. The activity of the promoters, that would be used to express a reporter gene, would be the key elements in the monitoring of simple and multiple pollutions. There was some expressed concern about the specificity of the response.
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Fabio Francesco Nocito highlighted the effect of the plant sulphate nutrition on the Cd and Zn tolerance
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Michael Weber, Adrian Craciun and Glenda Willems presented 3 talks on the use of hyperaccumulators as models to identify genes involved in heavy metal tolerance and accumulation in particular for Zn and Cd.
Comparison was systematically done with close non accumulator, nontolerant species. Genes involved in chelator biosynthesis (nicotianamine), in heavy metal transport, which are directly related to heavy metal

homeostasis have been identified and characterized. However the largest variation in expression between the hyperaccumulator Arabidopsis halleri and the non accumulator Arabidopsis petraea or A. thaliana , was for the class of genes involved in general metabolism. The structures of promoters of the genes which are constitutively overexpressed in hyperaccumulators seem different. Some of the transcriptomic studies were further confirmed at the metabolomic level. Three QTL were identified for Cd and Zn tolerance, with equal contribution (and without epistatic interaction), and which explain 50% of the tolerance characters.
This suggests the remaining 50% may be related to the large adaptation of metabolism. The identified QTL will help to reveal the” master genes” and the mystery of hyperaccumulation. The ”master genes” could also be transferred to higher biomass plants with a potential for phytoremediation of Zn/Cd polluted soils.
 Finally Sébastien Thomine presented the characterization of NRAMPs
(Natural Resistance Associated Macrophage Proteins), which are transporters of iron but also of Zn, Mn and Cd. In A. thaliana NRAMP3 and
4 are involved in the remobilisation from the vacuole. In Cd/Zn hyperaccumulators, those genes are overexpressed.
The open final discussion addressed the use of transgenic plants for the depollution of soils, which is still very controversial in Europe but in progress in the United States, the difficult transfer of knowledge from the lab to the field, the need of complementary physiological experiments.
Improving nutritional quality and safety of food crops
Session 1 (report by A. Cortes Lucas)
Interest in food crops’ element (metal) accumulation derives from two main worries: deficiency and toxicity.
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Approaches to control element deficiency in food go from food fortification and supplementation, to direct element addition to soils/plants, passing through plant genotypes’ improvement, or fertilizers enrichment. Legal, economical or ecological constraints vary from one country to another, from one case to another.
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Zinc and selenium deficiencies in human nutrition related with food crops have been pointed out.
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Approaches to reduce metal accumulation in food crops include soil element bioaccesibility management or plant genetic control.

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In any case, it is important to take into account interactions between elements, and site specific factors, and to understand the different mechanisms that are involved in the different steps of element translocation: soil-root, root-shoot and shoot-grain or edible part, with identification of functions and validation at the physiological level.
Session 2 (report by F. Laturnus)
Artak Ghandilyan reported the use of Quantitative Trait Loci (QTL) analysis as an unbiased method to identify genes controlling the uptake of minerals, such as Zn and Fe, by crops. As the lack of bioavailable Zn and Fe in human food can lead to human malnutrition, knowledge on processes controlling the uptake and distribution will improve food quality and human health. During the presentation and the following discussion it was highlighted that with the QTL method certain candidate genes improving the metal uptake have been identified in certain parts of the plant.
Pat Harvey presented a talk on PAHs with focus on food quality and food safety. The talk differs from the one announced and presented in the book of abstract. Pat emphasised that food safety and food quality are important focus in the new COST Action 859, and that future studies should be directed on transportation processes and kinetics ("where the compounds are going") to better evaluate necessary steps to increase/ensure food quality and safety.
As an example, Pat showed that although PAHs are mainly accumulated in the roots not in the shoots, could the formation of reactive compounds during the degradation of PAHs reduce food quality. In the following discussion,
Steve McGrath mentioned that already plenty of literature/studies are available on the uptake of organic contaminants by plants and referred to studies on PAHs done by his own group. Pat responded by highlighting that studies are available but information on the fate of these compounds in the plants is still lacking.
Piet Seuntjens described a project to develop a chain model of the fate and transfer of Cadmium combining all input and output pathways at a farm level.
The model includes transfer to vegetable food and feed, to meat, diary products and poultry, using equations based on critical review of available scientific literature. The results showed a large Cadmium input from the atmosphere and a less input from manure and phosphate fertiliser. Most
Cadmium will remain in soil, while small parts are transferred to crops and animals. However, data are still scarce on the actual Cadmium concentrations in food, and on the transfer of Cadmium between atmosphere - soil - plants.
The discussion focussed on the problem on how to avoid the Cadmium uptake from soil (through increasing soil pH, which will reduce the bio concentration factor - BCF), and on how reliable the present model is, i.e. level of confidence in prediction (to increase reliability, the model parameters need further optimisation).

General discussion (report by A.F. Lopez-Millan and S. Gawronski)
The COST Action 859 to some extend emerged and partly relates to the achievements of the former COST Action 837 therefore, it seams reasonable shortly memorize it. The COST Action 837 was dedicated to phytoremediation and in majority the research and discussions were concentrated on the plant species recommended for this technology.
In the present COST Action we are and will focus on developing our knowledge on using plant traits to improve quality and safety of food. As we have seen during this workshop participants concentrate on molecular level of species responses, and mechanisms of element uptake. In this morning session special attention was paid to several aspects of zinc and selenium as highly valuable micronutrients both for plants and for man. It was underlined that increasing zinc content in plant tissues, desired from human nutritional point of view, require also simultaneous maintaining other elements on proper level as well as organic compounds for example glutathione. High concentration of glutathione, on the other hand, might result in increased tolerance of other toxic elements, the presence of which in plant material should be avoided.
Selenium is an example of another essential microelement for which the demand is fairly constant and the range between being essential and toxic is rather narrow.
For recommendation of functional food not only cultivars with high content of these elements but also customs and preference of consumers must be taken into consideration such as species easy to eat at a proper amount to ensure diet requirements for example: cherry tomato or bean pods and so on.
Genomics enter to this study with wide application from molecular markers for low-Cd accumulation to identification of Qualitative Trait Loci (QTL) responsible for mineral nutrients homeostasis.
Much less advanced are studies with organic pollutants for example polyaromatic hydrocarbons (PAHs), which as we know lowers food quality.
Therefore further studies on decontamination or elimination PAHs from the plant material are required
Our basic knowledge in phytotechnologies increased in the last few years significantly, but we need to extend the effort of all members of this COST
Action for developing new phytotechnology and application in practice focusing on the topics of this COST Action.
Integration and application of phytotechnologies
Session 1 (report by S. Trapp and R. Haberl)

Speaker 1: André Gerth, Bioplanta Leipzig
Constructed wetlands - results and development in recent 10 years
Content: Several examples of constructed wetlands application
Discussion
Question: "What is the role of plants in the system, are they needed?"
Answer: "Plants are needed for shading, against clogging (providing long-term permeability), and the removal of bacteria is better."
Addition reporter: rhizosphere effect, oxygen transport to the rhizosphere, uptake of nutrients.
Question: "If constructed wetlands are built in developing countries, e.g., in
South America, is there not the risk of mosquito development?"
Answer: "This is an important issue that is often raised. Our wetland is in a semi-arid area, and there are no mosquito populations in this area. Besides, sewage treatment plants are at least 500 m distance of populated areas, and mosquitoes do rarely fly that distance."
Comment from reporter and audience: "Wetlands can be designed and constructed in a Mosquito adverse manner (no open water surfaces, i.e. dense vegetation), alternation of deep and shallow zones). Fish can be used to control mosquito development."
Speaker 2: Tomas Vanek, Prague, vice-chairman of Cost 859
Phytoremediation of explosives
Content: Uptake, degradation and distribution of TNT, PETN, NG in plants in the frame of phytoremediation of sites contaminated by ammunition factories.
Discussion
Question: "What is the fate of the N (in TNT)?"
Answer: "We made 14C autoradiography. Most labelled C (TNT or metabolites) remained in roots. But we have not analyzed the chemical form.
TNT can also be attached to the cell wall."
Question: "You talk about plants. Are you sure that it is not microorganisms that degrade the TNT?
”
Answer: "In the laboratory tests, we worked with sterile plants, so we can be sure that the degradation was by plants. In the field, we did not investigate this."
Speaker 3: Jan Bocian, Poland.
The economic analysis of phytotechnology application (willow-coppice vegetation filter) for conversion of water pollutants into energetic resources at the local scale - alternatives for the conventional sewage treatment.
Content: Application of willow coppice vegetation for modernization of 2 existing sewage treatment plants including an economic analysis.

Discussion
Question: "In your presentation, you calculate w ith 72 000 € income per year from wood production. On which area do you expect this?"
Answer: "40 hectare"
Comment from chairman: "Is this not high, compared to the approx. 500 € per year and hectare income that you can gain from conventional agriculture?"
Comment from audience: "The price for wood chips in Italy is now 1/2 the price for oil, so it becomes more and more attractive to use it for burning."
Question: "In your calculation you have a price drop after 3 years where does that stem from?"
Answer: "Initially, there are maintenance costs, which reduce after some time."
Speaker 4: Tanja Barac (now Hasselt University, Belgium)
Use of poplar trees and their associated microorganisms for remediation of a
BTEX contaminated groundwater.
Content: New results from endophytic bacteria and the Ford Ghenk plume phytoremediation study
Discussion
Question: "Was this technique used at the Ford site, i.e. was it legal to set free genetically modified bacteria?"
Answer: "At the field site, only naturally enriching endophytic bacteria occurred. The tests with modified bacteria were done only in the lab. But the technique does not need GMO bacteria, the endophytes can also be selected and breaded without.
Question: "Is there a transfer of plasmid DNA to the plants?"
Answer: "No, only to other endophytic bacteria."
Question: "If I understand it right, you can bring in bacterial DNA into trees without gene manipulation. Can there all bacterial DNA be used?"
Answer: "In principle, yes."
Comment: "Wow. This seems a very powerful technique."
Answer: "Yes."
Session 2 (report by J. Verkleij)
The session included four short lectures of 20 minutes and 19 posters, which were presented and discussed.
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In the discussion of Steven Rock’s presentation (USA) it was emphasized that the actual experience on large scale projects was more developed in the USA, but that Europe was ahead in the genetic research, particularly with respect to phytoextraction technologies. It should be recommendable

to have more interactions between these two approaches. Furthermore it was advised with respect to phytoextraction technologies not only to focus on the shoot part, but also to take care of the roots, which in many cases represent a much higher biomass product. There is a need to determine the optimum harvest time for plants in view of a more efficient phytoextraction of metals.
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The study presented by Nick Lepp (UK) was a nice example of natural attenuation: a former industrial waste site, contaminated with arsenic, was covered by a naturally-regenerated birch woodland and none of the foliar arsenic content exceeded concentrations higher than 1 mg/g DW. It was observed that re-vegetation of contaminated soils did not increase mobility of heavy metals, but actually limited the environmental mobility of As.
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The presentation of Valerie Bert (FR) dealt with the assessment of phytostabilisation efficiency of a heavily metal contaminated sediment using biological and physicochemical tools. In general basic slag was the most efficient additive to reduce the Zn and Cd plant-available fractions and concentrations in plant aerial parts. It was discussed whether the relatively high total Cu content in the soil solution after the phytostabilisation treatment was due to the lower pH or that the plantavailable fraction was still low and therefore non-toxic.
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The phytostabilisation of a Chromium-Copper-Arsenate (CCA) contaminated area was discussed in the paper by Michel Mench (FR).
Based on chemical data and soil ecotoxicity tests (radish, lettuce, earthworms and slugs), some soils within the site could be classified as highly ecotoxic. Due to a combination of soil amendments (iron grit and beringite, iron grit and sepiolite or iron grit) the soil ecotoxicity was strongly reduced and plant biomass and Rhizobium nodules were restored. These results should give further perspectives to investigate the responses of As- and metal tolerant plant species on a number of contaminated soils at a
European experimental site. In this way environmental risk assessment and soil remediation could be studied by scientists from all over Europe using innovative (bio) tests and biotechnology tools
General discussion (report by M. Greger)
Of the phytotechnology and applications discussed, soil remediation and wastewater treatments were the most commonly studied.
Soil remediation:
Phytostabilisation seems to be the working method as well as phytodegradation. Heavy metal extraction seems to have a bottleneck in the transfer problem of metals to shoot, probably the reason for shortage of industrial scale examples. However, as discussed below, this may be the case in high and moderate contaminated soil but not necessary at light metal contamination.
It was shown that a high soil contamination by toxic elements not necessarily means a problem, since plants can exclude elements at such sites, thus

having a low accumulation. Thus, such soils can be covered by plants by using phytostabilisation or assisted phytostabilisation.
Wastewater treatment:
This method is more advanced in full scales and treatment of domestic, industrial and more examples exist. Both microbes and plants are likely to be working in this treatment.
In the case of domestic wastewater it is necessary if using the water for field irrigation, to not forget about the hygienic part.
An economic approach where Salix is used in wastewater treatment was discussed. One has calculated that after some years there is an increasing economic aspect in the cultivation of this plant due to the bioenergy production. However, the calculation can be too optimistic since the energy fuel price is not stable in the future.
From this other comments came up.
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It is important to consider the economic part in phytoremediation.
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We know that wetland treatments are working and it is no longer necessary to investigate the processes, but instead look at the outcome and other qualities of it.
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It was also stated that we should look at the societies demand and what is really important for the society and not only what is of academic interest.
Meaning that still try to work on the phytoextraction possibilities where it could be used such as in light contaminated paddy field for rice cultivation
(or light contaminated agricultural soil for wheat production) since there are Cd contamination of rice (and wheat). Phytoextraction is truly working on light metal contaminated soil (shown for Salix).
Part 1: Emerging countries (report by C. Finnegan)
Trees, industrial crops, grass and legume based phytotechnologies to promote sustainable land use.
M.N.V. Prasad presented a talk on the use of phytotechnologies to promote sustainable land use in India. India comprises 15 agroclimatic zones and 12 ecoregions and it has 47,000 plant species. For a population of 1000 million,
55% of land is classed as arable. Soil conservation and restoration of degraded soils is the most serious environmental concern in India. Research has been carried out into the use of trees and grass, grown together, for the prevention of soil and nutrient loss from land-use systems. Agricultural

production of food products in contaminated areas is of human health concern, and so production of industrial crops not used for food production may be an alternative. An integrated approach may be used to remediate polluted soils for sustainable development. In discussion, it was suggested that while Vetiver is known to remove pesticides from contaminated soil, the removal of metals is a more controversial issue. The research carried out has been for biosorption and not accumulation of metals. The root mass, as a powder, may be used as a biofiltre. The point was then made that the use of trees for phytoremediation may not be effective, since the roots of trees can reach uncontaminated parts of soil and will therefore not improve soil quality.
It was also suggested that both Prosopis and Leucaena are not liked by cattle, are anti-nutritional, and will only be eaten in the absence of any alternative.
The role of phytotechnologies in the remediation of contaminated environment in Uzbekistan.
D. Egamberdiyeva presented a talk on the need for phytotechnologies to improve the quality of the natural environment in Uzbekistan. Uzbekistan has been an independent country since 1991. The country has traditionally been a very large producer of cotton, and the amount of irrigated land there is increasing. The key environmental problems in Uzbekistan include salinisation and degradation of land, an insufficient supply of drinking water, scarcity and pollution of water, air pollution in cities, accumulation of solid waste, contamination of food products, desertification and loss of biodiversity, soil erosion, and soil pollution with pesticides, herbicides and heavy metals.
Some initial research has been carried out into the levels of contaminants present in plants grown in industrially contaminated areas. In discussion, the point was raised that there are many possibilities for phytoremediation field experiments in Uzbekistan. Since there is no money available, collaborators are needed, to provide funding and expertise to Uzbekistan phytoremediation research. Although farmers now care about soil contamination, there is no information available to them.
Preliminary assessment potential for phytoremediation in Ukraine.
Lidiya Moklyachuk presented a talk on the possibilities for the use of phytoremediation of contaminated areas in Ukraine. The soil pollutants of most concern in the Ukraine are radionuclides from the Chernobyl accident, heavy metals from industry and persistent pesticides from abandoned pesticide storage warehouses. Radioactive contamination of the environment remains one of the most menacing legacies of the Chernobyl Nuclear Power
Plant accident in 1986. In the Ukraine alone more than 4.6 billion hectare of agricultural lands and forests have been exposed to radioactive pollution. All over the Ukraine, warehouses stored large quantities of pesticides, including many organochlorine pesticides. There is a substantial public health risk from poisoning of surface water and groundwater, and pesticide residues suspended in air, and there is an immediate need for remediation of soil in these areas. In discussion it was suggested that we should consider the
Chinese strategy, whereby crops grown for biomass production are used

simultaneously for phytoextraction. Farmers need to continue production and remediation. In the Ukraine, a different strategy may be needed, combining phytoremediation and phytoextraction, for contaminated areas.
Final Remarks
In the final discussion, it was confirmed that all speakers in this session have been accepted as members of COST 859. More collaboration is needed between COST members and emerging countries.
Part 2: Improving plants performance (report by J. Truu)
 Session first presentation was given by Dr. T. Kömives about the use of transgenic poplars with elevated glutathione content in phytoremediation.
Main outcome of the study was the finding that transgenic poplars with higher sulphydryl content were more suitable for contaminated soils than wild type poplars. He pointed that the field application of transgenic plants is dependent on legislation. During discussion it was suggested to use in practical phytoremediation unfertile transgenic plants.

Next presentation by Dr. A. Sirko showed that increased concentration of glutathione and phytochelatins in plant tissues did not lead to increased cadmium accumulation in the shoots. Questions about the effect of higher and lower concentration of Cd on accumulation were discussed, and it was proposed to use lead in further experiments.
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Plant intraspecific and metal specific variation was considered in the presentation of Dr. H. Schat. High level of variation was recorded, which was considered as excellent opportunity for further genetic and physiological dissection of hyperaccumulation traits.
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Candidate genes involved in zinc accumulation were revealed in study by
Dr. I. Talke and co-workers. They also studied gene copy numbers and promoter activity of candidate genes. Questions were asked about how Zn concentration in roots may be related to culture conditions and what kind of disinfection method to apply in such type of research.

Talk given by Dr. H. Morikawa showed that nitrogen dioxide at an ambient level exerted a multifunctional effect on plant growth, uptake of nutrients, and metabolism. During discussion comments about earlier experiments of same kind were made. Reply to question about in which form fixed NO
2
is present in plant, was that 7% in amino acids. There were also questions about nitrate reductase status in plant leaves and what processes in plants were enhanced by NO
2
.
Final discussion of the Workshop (report by M.P. Bernal and T. Vanek)
Dr. Vanek after acknowledging Dr. Barbafieri a nd Dr. Schwitzguébel for the excellent organisation, invited the WG leaders to summarise the contributions in this workshop.

Dr. Golan, in the name of the WG1 leaders, summarised the oral and poster contributions, indicating the balance existing with the presentations of the other WGs. He indicated the opportunity to focus on the dual aspect of phytoremediation fact/fiction, and pointed out the potential to go a long way, and the necessity to distinguish between the mechanisms of metal absorption and transport and the application of such mechanisms under real conditions.
Finally, the need to integrate the terms availability/ bioavailability/ extractability in relation to the metal forms absorbed in the soil, rhizosphere, and compartmentation in soil/plant system, etc, which was suggested as an idea for a future workshop theme.
Dr. Schroeder, as WG2 leader, indicated the 9 oral contributions on the subject. He stated the necessity of marrying the “omics” with the technology, as the work only involves model plants and model pollutants. The research on this subject has to meet the “real life” situation.
Dr. Harvey described the WG3 as a young group in this COST Action with respect to the previous Action 837. She considered it necessary to prepare the background t o decrease the “awful” compounds and increase the “good” nutritionally valuable compounds in the foodstuffs, using cellular location, bioavailability in soil and the availability for humans in the foodstuffs. We also need to know what is going on in vegetable food by progressing in mapping metal concentrations, ion chelators, and improvement of plant performance.
The increased focus on understanding distribution, leading to suggestions and advice, was also highlighted. She finally gave thanks to all contributors.
Dr. Bert, as one of the WG4 leaders, indicated the necessity to link mechanisms and demonstration projects. With respect to wetlands, there is a lot of information available and so demonstration projects are common in different countries. However, more demonstration projects on soil and sediments contamination are needed, as well as in risk assessment. Another aspect to be taken into account is the effect of phytotechnology in the ecosystem.
The usefulness of the links between the USA and Europe were pointed out by
Dr. Vanek, inviting Dr. Rock to give his opinion. He indicated that useful tools need to focus on a specific target. If there is a good plant for a purpose, try to obtain the adequate benefit. For instance, if we have a good plant for metal accumulation in the root we have to think about harvesting the roots instead of trying to improve the transport. We need to be more efficient with the tools we have now. In general, we move in common areas in the different countries.
Dr. Bernal finally pointed out that during the conference a lot was heard about
“omics” but very little about field phytoremediation experiment under real conditions, although there were several poster contributions. She highlighted the necessity to make the effort to integrate the laboratory genomic research into solving the real problems of soil contamination and rehabilitation.
The session was closed by Dr. Vanek giving thanks to Dr. Barbafieri for the excellent organisation and Dr. Schwitzguébel for the management of the workshop. Dr Barbafieri also acknowledged all participants for their contributions.