In the present study, changes in the infectivity and effectiveness of four Glomus mosseae strains of different origin were investigated in calcareous loamy chernozem soils treated with Cd at three levels (0, 50, 100 mg Cd kg −1 ) in a pot experiment. Frequency of infection (F%), arbuscular richness (a%) and shoot dry matter, macro-(N, P, K, S, Ca, Mg) and microelements (Zn, Cu, Ni, Mn, Mo, Co) and the Cd content of the host plants were compared to determine whether there was any variability in infectivity and effectiveness between G. mosseae strains of different origin. Functional diversity was found in the infectivity and effectiveness of the studied G. mosseae strains. In Cd-treated soil, AMF inoculation was beneficial to the plant growth, P uptake and shoot Cd content of the host. However, the higher uptake of other macro- and microelements was noted for non-mycorrhizal plants compared to mycorrhizal plants. The lower shoot content of some elements did not cause nutrient deficiency in mycorrhizal plants. The present results support the hypothesis that in polluted soils, the development of mycorrhizal symbiosis has the potential for AMF to protect their hosts against Cd toxicity rather than to improve nutrient uptake.

……statistically lower than in water only after 16 hours exposure to the extracts from mixed AMF strains inoculated plants, but no difference was found among the different exposure times. Growth of T. vulgaris was significantly increased only by the infections of mixed AMF strains.

Adaptability of five Glomus mosseae cultures of different origins to the soil cadmium (Cd) content and the changes of the efficiency of the symbiosis between the arbuscular mycorrhizal fungi (AMF) strains and white clover (Trifolium repens L.) hosts were investigated in a pot experiment. The parameters of mycorrhizal colonization of the different strains and efficiency such as macroand microelement content of the shoots of mycorrhizal and nonmycorrhizal plants, the plant growth response to the increasing soil Cd content (0, 50, 100 mg kg 21 ), and the response to the AMF inoculation were compared at harvesting after 11 and 20 weeks. Variability was observed in the tolerance of different G. mosseae strains to soil Cd loading. Arbuscular richness of the probable Cd-adapted strain was not influenced either by increasing soil Cd content or harvesting time, whereas that parameters of nonadapted strains showed decrease in time. The effect of different AMF inoculation on plant biomass production also varied significantly. The phytotoxicity level caused by Cd was alleviated in the case of inoculation with two strains the most. Higher acqusition of some essential macro-and microelements were observed in case of mycorrhizal plants compared to controls. The general occurence and effectiveness of G. mosseae AMF species is obviously related to intraspecific variability. The adequate selected stress-tolerant AMF strains can be useful in phytoremediation.