Short-Term Effects of Genetically Modified Potato on Arbuscular Mycorrhizal Fungal Communities

Arbuscular mycorrhizal (AM) fungi, among other soil microorganisms, have been proposed as biological indicators of normal rhizosphere structure and functionality. This makes them a useful functional group to monitor potential risks related to the use of genetically modified plants (GMPs). In this work, the effects of transgenic potato plants, with over-expression of antifungal genes, have been analyzed in short-term experiments with AM fungi. Samples of soil from agricultural sites, where potato has been cultivated for more than 100 years, were collected. Indigenous AM communities from these soils were analyzed and used as inoculum for microcosm assays with potato lines. Genetically modified (GM) traits did not have a marked effect on intraradical AM composition, being the phylotypes of the Paraglomeraceae family which established symbiosis in roots of all potato lines in greater proportion. Our results showed no adverse effects on normal colonization by AM fungi of GM potato. However, this does not abrogate the need for in-depth monitoring of each transgenic event in the context of its target soil.