Evaluation of selenium bioavailability to Brassica juncea in representative Chinese soils based on diffusive gradients in thin-films (DGT) and chemical extraction methods
Evaluation of selenium bioavailability to Brassica juncea in representative Chinese soils based on diffusive gradients in thin-films (DGT) and chemical extraction methods
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DOI：
10.1080/15226514.2020.1774502
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发表时间：
2020-06
影响因子：
3.7
通讯作者：
Zengyu Zhang;Fangke Shen;M. Gu;Yongxian Liu;Liushu Pan;M. Shohag;Tingting Li;Yanyan Wei
中科院分区：
文献类型：
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作者：
Zengyu Zhang;Fangke Shen;M. Gu;Yongxian Liu;Liushu Pan;M. Shohag;Tingting Li;Yanyan Wei
摘要 硒 (Se) 是人类必需的微量营养素，但通过食物链（例如蔬菜）摄入过量时会产生毒性。因此，了解土壤中硒的生物利用度与蔬菜可食部分吸收之间的关系势在必行。本研究通过比较薄膜扩散梯度（DGT）和化学提取方法，研究了用不同浓度的外源硒酸盐肥料（0–2 mg·kg−1）处理的六种中国代表性土壤中芥菜的硒生物利用度。不同提取方法测定的芥菜吸收硒量与土壤有效硒量的相关系数为：DGT>KCl>水>EDTA>KH2PO4>NaHCO3提取。此外，芥菜的土壤性质与化学提取方法测定的土壤硒浓度相关，而 DGT 方法与土壤性质无关。 DGT更适合测量Udic Ferrisols、Mollisols、Stagnic Anthrosols、河流壤质稻田土、粉质壤土和钙质风化土的Se阈值，其值分别为373.34、648.68、436.29、589.84、295.35和464.95 μg·L−1。因此，DGT可能是预测和评价不同土壤类型芥菜硒生物有效性的有效方法。
Abstract Selenium (Se) is an essential micronutrient for humans but is toxic when consumed in excess through the food chain, such as vegetables. Therefore, it is imperative to understand the relationship between the bioavailability of Se in soil and its uptake in edible parts of vegetables. This study investigated Se bioavailability of Brassica juncea in six representative Chinese soils treated with different concentrations of exogenous selenate fertilizer (0–2 mg·kg−1) by comparing diffusive gradients in thin-films (DGT) and chemical extraction methods. The correlation coefficients between the Se uptake by Brassica juncea and soil available Se determined by different extraction methods was as follows: DGT > KCl > Water > EDTA > KH2PO4 > NaHCO3 extractions. In addition, soil properties were correlated between Brassica juncea and soil Se concentrations determined by chemical extraction methods, while the DGT method was independent of soil properties. DGT was more suitable for the measurement of Se thresholds for Udic Ferrisols, Mollisols, Stagnic Anthrosols, Fluviogenic Loamy Paddy soil, Silty Loam soil, and Calcaric Regosols with values of 373.34, 648.68, 436.29, 589.84, 295.35, and 464.95 μg·L−1, respectively. Thus, DGT may be an effective method for the prediction and evaluation of Se bioavailability to Brassica juncea in different soil types.