Influence of arbuscular mycorrhiza on the growth and cadmium uptake of tobacco with inserted metallothionein gene

The development of AM did not differ between the transgenic and non-transgenic plants in either experiment. AM improved the phosphorus nutrition of the tobacco plants in both experiments, their biomass production, however, was increased only in sand, while in soil, it was lower or remained unchanged compared to non-mycorrhizal plants. AM decreased the Cd uptake of the tobacco plants per unit of shoot biomass in both experiments and decreased the Cd accumulation in the shoots of the transgenic tobacco relatively to the non-transgenic tobacco. It is concluded that AM symbiosis is likely to influence the heavy metal (HM) accumulation ability of plants targeted by transgenosis. Thus, AM must be considered in testing the transgenic plants as it can change the relative performance of the transgenic plants compared to the non-transgenic plants.