IMPORTANT LEGAL NOTICE - The information on this site is subject to a disclaimer and a copyright notice
Banner Research
English
 
  European Commission   > Research > GMO
 
EC-sponsored Research on Safety of Genetically Modified Organisms - A Review of Results
imageIntroductionimage Research areasimage Plant microbesimage Project 08
Graphic element Graphic element Graphic element

 
 button Introduction
image
 button Foreword
image
 button Research areas
imageimageimage Plants
imageimageimage Plant  microbes
imageimageimage Biocontrol
imageimageimage Food
imageimageimage Bioremediation
imageimageimage Tools
imageimageimage Fish
imageimageimage Vaccines
image
 button Index of participants
image
image IMPACT I and IMPACT II: Interactions between Microbial Inoculants and Resident Populations in the Rhizosphere of Agronomically Important Crops in Typical Soils

ECO-SAFE: Ecological and Environmental Biosafety Assessment of Novel Plant and Microbial Biotechnology Products

Background and objectives

Certain micro-organisms found in the rhizosphere are known to improve soil fertility and consequently plant health and growth. These micro-organisms supply nutrients to plants by degrading organic matter, convert atmospheric nitrogen into a usable form, protect plants from disease, and stimulate plant growth directly through the production of phytostimulating compounds. Modern European agriculture has relied extensively on the use of agri-chemicals, i.e. fertilisers, fungicides and pesticides, to increase crop yields. Although these have helped to improve crop yields there are environmental concerns regarding their use and application. Given these concerns, the increased use of micro-organisms is now seen as an advantageous alternative to chemical treatments and will contribute substantially to the goal of environmentally friendly, sustainable agriculture.

  Root nodules formed on the root system of a soybean plant. Nitrogen-fixing root nodule bacteria (Bradyrhizobium) present inside the nodule provide valuable organic nitrogen to the host plant, which promotes plant growth. image Root nodules formed on the root system of a soybean plant. Nitrogen-fixing root nodule bacteria (Bradyrhizobium) present inside the nodule provide valuable organic nitrogen to the host plant, which promotes plant growth.

The objective of the first project was to study the ecological interactions between commercially important GMOs and indigenous species of the rhizosphere of key European food crops. We aimed to develop microbial inoculants, that can effectively compete with agri-chemicals, for use as biocontrol agents, biofertilizers and phytostimulators and to assess the impact of new inoculants on indigenous bacterial, fungal and microfauna populations in soils. The second project, which has recently started, aims to construct strains that produce phytohormones and to test their impact and efficacy in field studies. Secondly, it will study the effect of signalling in the rhizosphere to gain an understanding of microbial communication.
Top

  Mycorrhizal fungi colonise the root systems of many plants and aid in the uptake of nutrients by the plant, thereby improving plant growth and overall health. image Mycorrhizal fungi colonise the root systems of many plants and aid in the uptake of nutrients by the plant, thereby improving plant growth and overall health.
image
  Scanning electron micrograph demonstrating the colonisation of wheat roots by strains of Azospirillium... a bacterial inoculant that acts as a phytostimulator. image Scanning electron micrograph demonstrating the colonisation of wheat roots by strains of Azospirillium... a bacterial inoculant that acts as a phytostimulator.


Approach and methodology


These projects used biotechnological techniques to improve the performance of microbial inoculants. We developed modified biocontrol agents, phytostimulators and biofertilizers and conducted field trials to assess their efficacy and impact on the soil ecosystem. We also evaluated the use of agricultural crops modified to produce anti-fungal proteins for plant disease control. The safety of modified bacterial inoculants and plants was examined in both laboratory and field conditions. We also developed consensus methods to measure biological perturbations in the soil ecosystem, whether such perturbations result from agricultural practice (e.g. fungicides), microbial inoculants or plants with modified agronomic traits.

  Azospirillum induces the proliferation of plant root hairs which can result in improved nutrient uptake. image Azospirillum induces the proliferation of plant root hairs which can result in improved nutrient uptake.


Main findings and outcome

We assessed modified biological control agents, phytostimulators and biofertilizers in laboratory, microcosm (greenhouse) and field trials. The inoculation of seeds with modified microbial inoculants does not adversely affect the indigenous bacterial, fungal and Arbuscular Mycorrhizal (AM) fungal populations. In addition, soil enzyme activities (used as a measurement of perturbations in the soil ecosystem) were not significantly affected by modified strains compared with wild-type inoculants. Furthermore, we demonstrated that simply growing a plant or using established farming practices, had a far greater impact on the soil microflora than inoculation with microbial inoculants. For example, the biodiversity of AM fungi in agricultural sites was significantly lower than in a nearby woodland site indicating that crop plants can select certain groups of AM fungi. Inoculation of plants with biocontrol agents did not affect AM fungal biodiversity. Similarly, AM fungi were not deterred from colonising roots of plants modified to produce anti-fungal proteins. A field trial conducted with GM plants demonstrated that the impact on indigenous microbial activity, measured by soil enzyme activities, was not attributable to plant modification, but was significantly affected by environmental variation (e.g. soil moisture content) and plant variety (i.e. different wild-type cultivars). The data accumulated during these projects strongly suggests that the genetically modified plants and microbial inoculants investigated do not have a negative impact on the indigenous microbial population and consequently have the potential to contribute to environmentally friendly agricultural practices.
Top

 

Activity 1.3.2 - Impact of wild type and GM biofertilizers and biopesticides on AM fungi.

Most PGPRs form a biofilm on the AM fungal surface (result of IMPACT I).

image    
   
image  
     
image    
     
image    


Conclusions

These projects have provided important biosafety information about the release of GMOs. We tested a number of GM microbial inoculants with relevance for environmentally friendly food production under commercial field conditions in a number of European countries. Data from field experiments indicate that there are no significant detrimental effects associated with the use of wild-type or genetically modified microbial inoculants on crop yield, soil biomass, soil fertility and selected soil micro-organisms, including taxonomically similar strains and beneficial soil micro-organisms.


Adhesion to mycorrhizal roots and AM fungal hyphae of WT bacteria and EPS-deficient mutants of A. brasilense.

image    
     
image    
     
image    
     

 

Major publications

Helgason T., Daniell T.J., Husband R., Fitter A.H. and Young J.P.W., “Ploughing up the wood-wide web”.
Nature, 394, 1998, p. 431.

Bekri M.A., Desair J., Proost P., Searle-van Leeuwen M., Vanderleyden J. and Vande Broek A., “Azospirillum irakanse produces a novel type of pectate lyase”.
J. Bacteriol, 181, 1999, pp. 2440-2447.

Barea J.M., Andrade G., Bianciotto V., Dowling D., Lohrke S., Bonfante P., O’Gara F. and Azcon-Aguilar C., “Impact on arbuscular mycorrhiza formation of Pseudomonas strains used as inoculants for biocontrol of soil-borne fungal plant pathogens”.
Appl. Environ. Microbiol., 64 (6), 1998, pp. 2304-2307.

Brito B., Martínez M., Fernández D., Rey L., Cabrera E., Palacios J.M., Imperial J. and Ruiz-Argüeso T., “Hydrogenase genes from Rhizobium leguminosarum bv. viciae are controlled by the nitrogen fixation regulatory protein NifA”, Proceedings of the National Academy of Sciences, USA, 1997, 94, pp. 6019-6024.

Chin-A-Woeng T.F.C., Bloemberg G.V., van der Bij A.J., van der Drift K.M.G.M, Schripsema J., Kroon B., Scheffer R.J., Keel C., Bakker P.A.H.M., Tichy H.V., de Bruijn F.J., Thomas-Oates and Lugtenberg E.J.J., “Biocontrol by phenazine-1-carboxamide-producing Pseudomonas chlororaphis PCL1391 of tomato root rot caused by Fusarium oxysporum f.sp. radicis lycopersici”.
Mol. Plant-Microbe Inter., 11, 1998, pp. 1069-1077.
image imageimage image
imageResearch project
 
Contract number
BIO2-CT93-0053
BIO4-CT96-0027
QLK3-2000-01759

Overall period
September 1993 –
December 2002

Coordinator
F. O’Gara
University College Cork (IE)

Project website address
http://www.ucc.ie/biomerit/
ecosafe.htm
image


Partners


IMPACT I and IMPACT II

B.J.J. Lugtenberg

Leiden University (NL)

J-M. Barea Navarro
CSIC
Estación Experimental del Zaidín
Granada (ES)

P. Bonfante
Università di Torino (IT)

G. Défago
Swiss Federal Institute of Technology
Zurich (CH)

V. Grogan, J. Broderick
Irish Sugar plc.
Carlow (IE)

D. Haas
Université de Lausanne (CH)

J.M. Lynch
University of Surrey (UK)

M.P. Nuti
Università di Pisa (IT)

J. Olivares
CSIC
Estación Experimental del Zaídin
Granada (ES)

U. Peruch
Agronomica S.r.l. Consortile
Ravenna (IT)

A. Pühler
Universität Bielefeld (DE)

T. Ruiz-Argueso
Universidad Politecnica de Madrid (ES)

R.A. Scheffer
Novartis Seeds B.V.
Enkhuizen (NL)

R. Simon
TÜV Energie- und Systemtechnik GmbH
Freiberg (DE)

J. Vanderleyden
Katholieke Universiteit Leuven
Heverlee (BE)

P. Young
University of York (UK)

S. Casella
Università degli Studi di Padova (IT)

A. Greenland
Zeneca Agrochemicals
Bracknell (UK)


ECO-SAFE

B.J.J. Lugtenberg

Leiden University (NL)

J-M. Barea Navarro
CSIC
Estación Experimental del Zaidín
Granada (ES)

G. Défago
Swiss Federal Institute of Technology
Zurich (CH)

J. Broderick
Irish Sugar plc.
Carlow (IE)

D. Haas
Université de Lausanne (CH)

M.P. Nuti
Università di Pisa (IT)

T. Ruiz-Argueso
Universidad Politecnica de Madrid (ES)

J. Vanderleyden
Katholieke Universiteit Leuven
Heverlee (BE)

P. Young
University of York (UK)

Y. Dessaux
CNRS, Institut des Sciences Végétales
Gif-sur-Yvette (FR)

D. King
International Federation of Agricultural Producers
Paris (FR)

R. Fray
University of Nottingham
Loughborough (UK)

J.A. Downie
John Innes Centre
Norwich (UK)

Y. Moënne-Loccoz
Université Claude Bernard Lyon 1
Villeurbanne (FR)

P. Wadoux
Merck Lipha (Lipha SA)
Meyzieu (FR)

Y. Okon
Hebrew University of Jerusalem (IL)

 
 
Previous project | Plant microbes contents | Next project | Top