Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
Environ Geochem Health. 2013 Dec;35(6):767-78. doi: 10.1007/s10653-013-9533-z. Epub 2013 May 30.
Paddy rice (Oryza sativa L.) is a staple food and one of the major sources of dietary arsenic (As) and cadmium (Cd) in Asia. A field experiment was conducted to investigate the effects of four water management regimes (aerobic, intermittent irrigation, conventional irrigation and flooding) on As and Cd accumulation in seven major rice cultivars grown in Zhejiang province, east China. With increasing irrigation from aerobic to flooded conditions, the soil HCl-extractable As concentrations increased significantly and the HCl-extractable Cd concentrations decreased significantly. These trends were consistent with the As and Cd concentrations in the straw, husk and brown rice. Water management both before and after the full tillering stage affected As and Cd accumulation in the grains. The intermittent and conventional treatments produced higher grain yields than the aerobic and flooded treatments. Cd concentrations in brown rice varied 13.1-40.8 times and As varied 1.75-8.80 times among the four water management regimes. Cd and As accumulation in brown rice varied among the rice cultivars, with Guodao 6 (GD6) was a low Cd but high-As-accumulating cultivar while Indonesia (IR) and Yongyou 9 (YY9) were low As but high-Cd-accumulating cultivars. Brown rice Cd and As concentrations in the 7 cultivars were significantly negatively correlated. The results indicate that As and Cd accumulated in rice grains with opposite trends that were influenced by both water management and rice cultivar. Production of 'safe' rice with respect to As and Cd might be possible by balancing water management and rice cultivar according to the severity of soil pollution.
水稻（Oryza sativa L.）是主食，也是亚洲地区膳食砷（As）和镉（Cd）的主要来源之一。本田间试验研究了 4 种水分管理模式（好气、间歇灌溉、常规灌溉和淹水）对中国东部浙江省种植的 7 个主要水稻品种中 As 和 Cd 积累的影响。随着好气到淹水灌溉的增加，土壤 HCl 可提取态 As 浓度显著增加，HCl 可提取态 Cd 浓度显著降低。这种趋势与稻草、稻壳和糙米中的 As 和 Cd 浓度一致。分孽期前后的水分管理均影响了稻谷中 As 和 Cd 的积累。与好气和淹水处理相比，间歇和常规处理的稻谷产量更高。糙米中 Cd 浓度在 4 种水分管理模式下变化 13.1-40.8 倍，As 浓度变化 1.75-8.80 倍。不同水稻品种糙米中 Cd 和 As 的积累差异较大，其中，国稻 6 号（GD6）是低 Cd 但高 As 积累品种，而印度尼西亚稻（IR）和甬优 9 号（YY9）是低 As 但高 Cd 积累品种。7 个品种糙米中 Cd 和 As 浓度呈显著负相关。结果表明，As 和 Cd 随水分管理和水稻品种的不同而在稻谷中积累，呈相反趋势。通过根据土壤污染的严重程度平衡水分管理和水稻品种，可能生产出安全的 As 和 Cd 稻谷。
