Zou Li, Shang Qiuyao, Li Zhixian, Xing Zhenan, Chen Guoliang, Chen Zhang, Zhou Jianlin, Liu Xiling
School of Resource Environment and Safety Engineering, Hunan University of Science and Technology, Xiangtan, China.
Hunan Province Key Laboratory of Coal Resources Clean-utilization and Mine Environment Protection, Xiangtan, China.
J Sci Food Agric. 2025 Aug 30;105(11):5780-5794. doi: 10.1002/jsfa.14298. Epub 2025 Apr 24.
Intercropping emerged as an agricultural technique exhibiting remarkable potential and benefits in promoting safe crop cultivation in heavy metal contaminated soils. In the present study, we set up five treatments of maize monoculture, soybean monoculture, Sedum Alfredii monoculture, maize/Sedum Alfredii and soybean/Sedum Alfredii intercropping and revealed the mechanism of intercropping on the yield of maize and soybean, as well as on the uptake of manganese (Mn), cadmium (Cd) and lead (Pb), from the perspective of root exudates by a randomized block test in the field.
The results showed that intercropped maize yield increased by 16.35% compared to monoculture maize in the maize/Sedum alfredii system. Meanwhile, the contents of Mn, Cd and Pb in the rhizosphere soil of intercropped maize were lower than those of monoculture maize, with significant reductions in acid-soluble and reducible Mn and Cd. By contrast, the soybean/Sedum Alfredii intercropping system, showed no significant differences in soybean yield, heavy metal accumulation in organs, or rhizosphere soil concentrations between intercropped and monoculture soybeans. Further analysis of the maize rhizosphere microenvironment revealed that citric acid and malic acid, as secreted by intercropped maize roots, were key factors influencing the morphological transformation of Mn and Cd in the soil. These acids also reduced the absorption and accumulation of Mn and Cd in intercropped maize.
The findings of the present study provide critical insights into heavy metal uptake mechanisms in intercropping systems and offer a novel strategy for the sustainable remediation and utilization of heavy metal-contaminated farmland. © 2025 Society of Chemical Industry.
间作作为一种农业技术，在促进重金属污染土壤中作物安全种植方面展现出显著潜力和益处。在本研究中，我们设置了玉米单作、大豆单作、东南景天单作、玉米/东南景天和大豆/东南景天间作五种处理方式，通过田间随机区组试验，从根系分泌物角度揭示了间作对玉米和大豆产量以及锰（Mn）、镉（Cd）和铅（Pb）吸收的影响机制。
结果表明，在玉米/东南景天体系中，间作玉米产量比单作玉米提高了16.35%。同时，间作玉米根际土壤中Mn、Cd和Pb的含量低于单作玉米，酸溶性和可还原态的Mn和Cd显著降低。相比之下，大豆/东南景天间作体系中，间作大豆与单作大豆在产量、器官重金属积累或根际土壤浓度方面均无显著差异。对玉米根际微环境的进一步分析表明，间作玉米根系分泌的柠檬酸和苹果酸是影响土壤中Mn和Cd形态转化的关键因素。这些酸还减少了间作玉米对Mn和Cd的吸收与积累。
本研究结果为间作系统中重金属吸收机制提供了重要见解，并为重污染农田的可持续修复与利用提供了新策略。© 2025化学工业协会。
