Effects of the arbuscular mycorrhizal fungi on cadmium accumulation and transport in Capsicum annum L.

【Objective】To investigate the effects of arbuscular mycorrhizal fungi on cadmium(Cd) accumulation and transport in Capsicum annum L.(pepper), so as to provide reference for the application of preventing Cd transfer to the above-ground part of pepper and phytoremediation.【Method】The experiment was carried out with Layan 201 as the material and planted in pot, pepper was inoculated Rhizophagus intraradices and Funneliformis mosseae respectively.Analyzed the variation of Cd content in soil with and without inoculation, pepper root and aboveground part, and explored and discussed the effects of inoculating R.intraradices and F.mosseae on accumulation and transport Cd in pepper.【Result】Compared with the non-inoculation treatment, the total content of Cd in soil with the R.intraradices and F.mosseae inoculated significantly increased by 10.80% and 9.98%(P< 0.05, the same below), and the proportion of Cd in different forms in soil changed.The residual Cd increased by 79.82% and 95.44%.While, with regard of the proportion of acid-soluble Cd, the migration risk decreased by 32.19% and 29.45%.With R.intraradices and F.mosseae inoculated in soil, Cd content in the root system increased by 39.57% and 53.13%, and Cd enrichment coefficient in the root system increased by 33.15% and 40.68%, while Cd content in the aboveground part decreased by 15.02% and 9.30%.Cd enrichment coefficient in the aboveground part decreased by 24.35% and 18.91% and Cd transport coefficient in pepper body decreased by 30.15% and 33.72%.Based on canonical correlation analysis, residual state Cd with a large typical weight had a positive effect on the change of Cd content in soil, and Cd enrichment coefficient in root and Cd transport coefficient in pepper had negative effect on the change of Cd content.For the analysis of typical loading and cross loading, Cd in low acid-soluble state in soil resulted in weak removal degree, while Cd in high residual state resulted in strong retention degree, so pepper had poor ability to accumulate and transfer Cd.【Conclusion】The distribution of Cd between aboveground part and root of pepper is controlled by inoculation of mycorrhizal fungi, and it can inhibit the transfer of Cd in soil from root to aboveground part.