Liu Yang, Qi Ming-Xing, Wang Min, Liu Na-Na, Pornpimol Kleawsampanjai, Zhou Fei, Zhai Hui, Wang Meng-Ke, Ren Rui, Liang Dong-Li
College of Natural Resources and Environment, Northwest A&F University, Yangling 712100, China.
Shaanxi Hydrogeological Engneering Geology and Environment Geology Survey Center, Xi'an 710068, China.
Huan Jing Ke Xue. 2021 Apr 8;42(4):2024-2030. doi: 10.13227/j.hjkx.202009017.
This study explored the discrepancy in the detoxification effects of different exogenous selenium (Se) species in cadmium (Cd)-contaminated soil to provide a scientific basis for the control of Cd pollution in the soil and the safe production of crops. A pot experiment was conducted to compare the effects of different concentrations (0, 0.5, 1.0, and 2.5 mg·kg) of selenite and selenate on the growth (root length, shoot height, biomass, and photosynthetic parameters), uptake, and translocation of Cd on pak choi in Cd-contaminated soil. The results indicated that the detoxification effect of a low Se concentration (≤1.0 mg·kg) treatment on Cd was better than that with a high Se concentration (2.5 mg·kg) treatment, and the selenite treatment demonstrated a greater detoxification effect on Cd than the corresponding selenate treatment. Meanwhile, the application of low-concentration selenite and selenate both increased the SPAD value, , , , biomass, and shoot length of the pak choi, and the 1.0 mg·kg selenite treatment had the most significant (<0.05) effect (except ). Nevertheless, the photosynthetic parameters of the pak choi under the high-concentration Se were significantly lower than those under the low Se concentration treatment (except , <0.05). Compared with the treatment without Se (control), the uptake of Cd in the pak choi was reduced under different Se treatments. Compared with the control, the Cd concentration in the shoots of the pak choi treated with 1.0 mg·kg of selenite and selenate decreased by 40.0% and 20.5% (<0.05), respectively. In addition, the translocation of Cd from the root to the shoot was significantly reduced under the 0.5 mg·kg selenate treatment, while the high-concentration treatments of either exogenous Se promoted the translocation of Cd. Overall, applying the appropriate amount of exogenous Se could promote the photosynthesis and biomass of pak choi, and reduce the accumulation of Cd in pak choi. Therefore, the 1.0 mg·kg selenite treatment is recommended for the control and safe utilization of Cd in Cd-contaminated soil.
本研究探讨了不同外源硒（Se）形态对镉（Cd）污染土壤的解毒效果差异，为土壤Cd污染治理及作物安全生产提供科学依据。通过盆栽试验，比较了不同浓度（0、0.5、1.0和2.5 mg·kg）的亚硒酸盐和硒酸盐对Cd污染土壤中小白菜生长（根长、株高、生物量和光合参数）、Cd吸收及转运的影响。结果表明，低硒浓度（≤1.0 mg·kg）处理对Cd的解毒效果优于高硒浓度（2.5 mg·kg）处理，且亚硒酸盐处理对Cd的解毒效果大于相应的硒酸盐处理。同时，低浓度亚硒酸盐和硒酸盐的施用均提高了小白菜的SPAD值、 、 、 、生物量和株高，其中1.0 mg·kg亚硒酸盐处理效果最显著（<0.05）（ 除外）。然而，高浓度硒处理下小白菜的光合参数显著低于低硒浓度处理（ 除外，<0.05）。与不施硒处理（对照）相比，不同硒处理均降低了小白菜对Cd的吸收。与对照相比，1.0 mg·kg亚硒酸盐和硒酸盐处理的小白菜地上部Cd浓度分别降低了40.0%和20.5%（<0.05）。此外，0.5 mg·kg硒酸盐处理显著降低了Cd从根向地上部的转运，而两种外源硒的高浓度处理均促进了Cd的转运。总体而言，施用适量外源硒可促进小白菜的光合作用和生物量，并减少Cd在小白菜中的积累。因此，推荐采用1.0 mg·kg亚硒酸盐处理来治理Cd污染土壤并实现其安全利用。
