Causal analysis between rice growth and cadmium accumulation and transfer under arbuscular mycorrhizal inoculation

Abstract

Abstract Cadmium contamination of rice is a serious hazard to human health in recent years. To investigate the effects of AMF on cadmium translocation of rice, a pot experiment was adopted to compare and analyze the effects of AMF on the growth and Cd content of rice under seven soil Cd levels. The results showed that (1) AMF promoted the growth of rice especially the growth of root system. The number of large individuals of host plants increased and their plasticity was enhanced after AMF inoculation. (2) The Cd concentration in rice roots of AMF treatment group were significantly higher than those of blank control group, indicating that the AMF fixed more Cd in rice roots. It is the opposite in rice seeds and it indicated that the host plant actively reduce the Cd accumulation from the seed rather than dilution effect under AMF regulation. (3) The path coefficient of each variable were different in different treatment. It indicates that the direct effect of cadmium content in soil on the accumulation of cadmium content in seeds was reduced by AMF inoculation. In conclusion, the effect of mycorrhizal on cadmium transport in plants is complex. This is because the accumulation of Cd is always accompanied by the simultaneous growth dilution and compensatory accumulation caused by mycorrhizal effect, which is difficult to be quantitatively analyzed. The AMF inoculation is helpful to solve the safety of rice production under the condition of medium and light cadmium pollution