Abstract

This project assesses the impact of three nonchemical strategies to control potato pathogens, i.e. via transgenic lines carrying T4 lysozyme or cecropin/attacin genes or avirulent mutants of Ralstonia solanacearum.

Three aspects will be addressed:

• The impact on the natural microbiota associated with potato.
• The impact on pathogen genetic diversity.
• The efficacy of the strategy.

The work will be executed in greenhouses and the field, in a concerted fashion. The field work will be concentrated at 2, i.e. Southern and Northern, locations. The Consortium consists of 7 partners, plus 3 commercial partners and a communication specialist. The evaluation of the impact of the 3 strategies will be useful for European decision makers.

Objectives

This project examines the ecological impact of three biotechnological approaches to the control of bacterial potato pathogens.

The specific objectives are:

• To assess the effects of the selected strategies for the control of potato pathogens on the structural and functional diversity of the microflora associated with potato.
• To assess the effects of the selected strategies on the genetic diversity of the pathogen populations targeted in the potato rhizosphere.
• To evaluate the feasibility of the selected strategies to reduce the threat posed to potato cropping by bacterial pathogens.
• To recommend the most viable strategy for non-chemical control of bacterial phytopathogens.

Description of the work

This project encompasses experimental work in seven laboratories, which have complementary expertise and tasks. The work has been divided into six workpackages numbered WP1 through WP6, each one of which is led by a work package leader. WP1 is concerned with the adaptation of available methods as well as the preparation of additional tools for the ecological assessments, and will have the involvement, in a complementary fashion, of all partners. WP2 deals with the establishment of the ecological baseline, i.e. will assess, in the field, the microbiota commonly associated with potato. In this WP, field work is to be performed at two locations (North-South), after which samples will be analysed by selected partners. WP3 is concerned with the screening, in the greenhouse, of the efficacy of the different available varieties of the transgenic plants and hrp mutants; four partners will be involved. This will result in a selection of a limited number of most promising strategies which will be assessed in greenhouse (WP4) and the field (WP5a and b). In WP4, two partners, supported by a further one, will perform an assessment of the selected strategies regarding the ecological behaviour (survival, plant tissue colonisation, localisation) of marked R. solanacearum as well as the hrp biocontrol agents. In addition, the efficacy in the control of Erwinia spp. will be assessed. In WP5a and b, the impact and efficacies of the selected transgenic plants and bacteria will be tested in the field at two locations, in a similar concerted effort as under WP2. Together, these workpackages will yield data important for a final assessment of the efficacy of the selected approaches versus their impact. WP6 is concerned with overall and specific coordination, and, most importantly, diffusion of the results. To achieve optimal diffusion, acceptability and marketability, a specialist who will focus on communication will be involved.

Deliverables

The (overall) deliverables are (T = months into the project):

• T6: European hrp mutants; M1b - website.
• T18: Efficacy screening.
• T24: Ecological baseline.
• T27: Strategy selected.
• T36: Impact on microbial and pathogen diversity; brochure.

Contacts

Coordinator

• J.D. van ELSAS / Plant Research International Crop and Production Ecology / NETHERLANDS

Participant

• A. SESSITSCH / ARCS, Division of Life Sciences Department of Biotechnology / AUSTRIA
• K. SMALLA / BBA, Insitute of Plant Virology Microbiology and Biosafety / GERMANY
• G SADDLER / CABI, Bioscience UNITED KINGDOM
• M.M. LOPEZ / IVIA, Dep de Proteccion Vegetal y Biotecnol Lab de Bacterio., Apartado Oficial / SPAIN
• A. TRIGALET / Lab de Biol. Moleculaire des Rel. Plantes- Microorganismes / FRANCE
• Janet K. JANSSON / SH, Section for Natural Sciences Sodertorn University College / SWEDEN