Objective To screen the crop varieties with low accumulation of heavy metal Cd suitable for cultivation in Qinghai and evaluate of their agricultural product safety. Methods Through field experiments, 9 crops, including barley, oilseed rape and broad bean, were planted in heavy metal-contaminated arable land in a field trial to analyze the Cd content in the roots, plants, seeds and corresponding soils of different crops. Cd content of different crop samples was measured by inductively coupled plasma atomic emission spectrometer (ICP-OES) after digestion in a graphite furnace. The enrichment capacity of each tissue and organ of the crop was analyzed by the enrichment coefficient method, and the non-carcinogenic health risk of Cd in crop seeds was evaluated by the target hazard quotient (THQ) method. Results The soil Cd content of barley and wheat exceeded the standard, but the seed Cd content of all crops met the national standard; the Cd enrichment capacity of wheat roots and plants was lower than that of the other crops, and the lowest soil Cd enrichment capacity of crop seeds was found in oats and wheat; there was no health risk for adults due to the intake of Cd from the edible parts of the 6 kinds of crops, and there was a health risk for children due to the intake of Cd from the edible parts of barley and potatoes. Conclusion Oilseed rape and oats is a kind of Cd low-accumulating crop suitable for local cultivation, which can ensure the safe utilization of local farmland. Therefore, this study can provide a scientific basis for screening crop varieties with low Cd accumulation and applying them on a large scale to polluted croplands in Qinghai.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |