Three-season rotation of chicory-tobacco-peanut with high biomass and bioconcentration factors effectively remediates cadmium-contaminated farmland.

Traditional phytoremediation is one approach to remediate heavy metal pollution. In developing countries, the key factor in promoting practical application of phytoremediation in polluted soils is selecting suitable plants that are tolerant to heavy metals and also produce products with economic value. Therefore, a field experiment was conducted with a three-season chicory-tobacco-peanut rotation to determine effects on remediation of cadmium (Cd)-contaminated farmland in China. All crops had strong Cd accumulation capacity, with bioconcentration factors of 6.61 to 11.97 in chicory, 3.85 to 21.61 in tobacco, and 1.36 to 7.0 in peanut. Yield of total dry biomass reached 32.4 t ha, and the Cd phytoextraction efficiency was 10.3% per year. Aboveground tissues of the three crops accounted for 83.9 to 91.2% of total biomass in the rotation experiment. Cd content in peanut grain and oil met the National Food Safety Standard of China (0.5 mg kg, GB 2762-2017) and the Food Contaminant Limit of the European Union (0.1 mg kg, 18,812,006). Therefore, in addition to phytoremediation of Cd-contaminated soils, the chicory-tobacco-peanut rotation system can also produce economic benefits for local farmers.