Arbusular Mycorrhizal Fungi Effects of the Growth, Cd Uptake and Physiology of <i>Solanum lycopersicum</i> Seedlings under Cd Stress

Abstract

The effects of three arbuscular mycorrhizal fungi (AMF) on the growth, Cd uptake and some physio-biochemical indexes of Solanum lycopersicum seedlings under different levels of Cd stress were investigated in a pot study. Generally, the symbiotic relationship between Solanum lycopersicum and AMF can be well established under Cd stress. This was reflected by the better physio-biochemical index of the plants inoculated with G. constrictum, G. mosseae and G. intraradices whose colonization rates were between 41.4% and 76.1%. Compared with the non-inoculated ones, G. constrictum inoculation enhanced the plant biomass at 50 mg kg-1 Cd addition level. AM colonization increased the Cd distribution to the roots in plants and alleviated shoots from high Cd stress, and thus increased the shoot biomass in the end. At the high Cd addition level, mycorrhizal plants reacted differently in the reduction of the contents of MDA, by influencing the soluble sugar, POD activity, SOD activity and so on. Our results showed that mycorrhizal colonization was beneficial to the Cd translocation in plants and reduced the membrane lipid peroxidation in plants under serious Cd stress. However, the mechanisms of mycorrhizal protection in plants were influenced by many factors and still need to be further studied.