Soil microbes play key roles in ecosystems and influence ecosystem processes, including nutrient acquisition, nitrogen cycling, carbon cycling, and soil formation. Soil microbes are the majority in soil and a large portion of the genetic diversity on Earth. Many microbes live in association with plant roots and can promote plant productivity and provide protection against stress and disease. Other microbes acts as pathogens and reduce plant growth. Sound environmental and agricultural practices favour balanced composition of biotic agents population in the rhizosphere. Well balanced micro-organisms population favours colonization of soil and nutrients intake, limits occurrence of pathogens (biotic stress), supports the development of commensal or symbiotic relationship between plant and micro-organisms, with a good tempering effect regarding abiotic stress (good water retention capacity, available macro- and micronutrients). Cultivated soils have been extensively studied. Pristine rhizospheres are less studied although these ecological niches contain important micro-flora and -fauna or help conceive the complex ecological microbes-plant relationship in soil, in the rhizosphere. The purposes of this project are:- to organize cooperation between specialised collections containing microbes isolated from the rhizosphere,- to constitute a common wide-range pool of micro-biodiversity exploitable for research and industry: the Pan-European Rhizosphere resources network (PERN).Collaboration between culture collections having material from West-European ecosystems and Russian Biological Resources Centres having micro-organisms from East-European biotopes will create a coordinated network of combined human expertise and culture collections. The network will offer scientists facilitated access to a wide range of micro-organisms coming from a broad spectrum of ecological zones spread over an extensive geographical range to study and exploit.