Technical rule 2011-06
This document specifies a method to evaluate the acute effects of pollutants on spore germination of a mycorrhizal fungus, Glomus mosseae. This acute toxicity bioassay allows the evaluation of effects of pollutants and contaminated soils on beneficial soil microorganisms important for plant growth within the concept of sustainable agriculture. This document is applicable to - chemical substances, and - contaminated soils, waste and soil-waste mixture and sludge. Mycorrhizal fungi are important components of the soil microbial community and key organisms in plant/soil systems. The root symbiosis they form represents a direct link between the soil and the large majority (80 %) of vascular plant species, in natural and agricultural environments. Mycorrhizal fungi provide several benefits to the host plant. This includes enhanced growth, improved mineral nutrition, greater drought resistance, and protection against pathogens and heavy metal stress. Several studies have shown that mycorrhizal fungi are sensitive to pollutants such as metallic trace elements and polycyclic aromatic hydrocarbons, and to sewage sludges even when no phytotoxic effects on the host plant are observed. As mycorrhizal fungi fulfil most of the criteria for bioindicator organisms (ubiquitous in soil, sensitive to pollutants, ecologically relevant role in plant health and ecosystems), it appeared important to take them into account in hazard and environmental risk assessments linked to pollutants, contaminated soils and to the use of sewage sludge in agriculture. This test can be directly performed with sludges or soils without any extraction step. The Committee responsible for this document is NA 119-01-02-04 UA "Biologische Verfahren" ("Biological methods") at DIN.