Arbuscular mycorrhizal fungi(AMF)can form symbiotic relationships with most crops,but their impact on the environmental migration of cadmium(Cd)in farmland is limited.A field experiment was per-formed in the rainy sea...Arbuscular mycorrhizal fungi(AMF)can form symbiotic relationships with most crops,but their impact on the environmental migration of cadmium(Cd)in farmland is limited.A field experiment was per-formed in the rainy season(May-October)for two years in Cd-polluted farmland used for maize cultivation.A fungicide(benomyl)was used to specifically inhibit native AMF growth in the farmland.The growth and Cd uptake of maize and the Cd concentration and loss in runoff and interflow were investigated.Benomyl strongly and significantly inhibited AMF colonization rate in maize roots,reduced the contents of total and easily extractable glomalin-related soil protein(GRSP)in soil and the Cd uptake in maize roots,and increased the Cd uptake in shoots.Particulate Cd was the main form of Cd loss in runoff,while dissolved Cd was the main form of Cd leaching loss at depths of 20 cm and 40 cm.Inhibiting AMF increased the Cd concentration in runoff and interflow and promoted dissolved Cd loss in runoff and interflow at 20 cm depth by 34.7%and 68.0%and particulate Cd loss by 46.4%and 19.7%,respectively.Furthermore,the AMF colonization rate in maize roots and the GRSP content in soil were significantly positively correlated with Cd uptake in roots and negatively correlated with the concentration and loss of Cd in runoff and interflow.These results indicated that the benomyl-induced inhibition of native AMF promoted Cd transfer to maize shoots and increased Cd loss via runoff and interflow from polluted farmland.展开更多
基金supported by the National Natural Science Foundation of China(Nos.42177381 and 41661056)the Reserve Talents Fund for Young and Middle-Aged Academic and Technological Leaders in Yunnan Province(Nos.2018HB043 and 202005AC160038).
文摘Arbuscular mycorrhizal fungi(AMF)can form symbiotic relationships with most crops,but their impact on the environmental migration of cadmium(Cd)in farmland is limited.A field experiment was per-formed in the rainy season(May-October)for two years in Cd-polluted farmland used for maize cultivation.A fungicide(benomyl)was used to specifically inhibit native AMF growth in the farmland.The growth and Cd uptake of maize and the Cd concentration and loss in runoff and interflow were investigated.Benomyl strongly and significantly inhibited AMF colonization rate in maize roots,reduced the contents of total and easily extractable glomalin-related soil protein(GRSP)in soil and the Cd uptake in maize roots,and increased the Cd uptake in shoots.Particulate Cd was the main form of Cd loss in runoff,while dissolved Cd was the main form of Cd leaching loss at depths of 20 cm and 40 cm.Inhibiting AMF increased the Cd concentration in runoff and interflow and promoted dissolved Cd loss in runoff and interflow at 20 cm depth by 34.7%and 68.0%and particulate Cd loss by 46.4%and 19.7%,respectively.Furthermore,the AMF colonization rate in maize roots and the GRSP content in soil were significantly positively correlated with Cd uptake in roots and negatively correlated with the concentration and loss of Cd in runoff and interflow.These results indicated that the benomyl-induced inhibition of native AMF promoted Cd transfer to maize shoots and increased Cd loss via runoff and interflow from polluted farmland.
