de Oliveira Natalia Trajano, Namorato Filipe Aiura, Rao Sombir, de Souza Cardoso Arnon Afonso, de Rezende Pedro Milanez, Guilherme Luiz Roberto Guimarães, Liu Jiping, Li Li
Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture, Agricultural Research Service, Cornell University, Ithaca, NY, 14853, USA; Department of Agronomy, Federal University of Lavras (ESAL-UFLA), Lavras, MG, 37200-900, Brazil.
Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture, Agricultural Research Service, Cornell University, Ithaca, NY, 14853, USA; Soil Science Department, Federal University of Lavras (ESAL-UFLA), Lavras, MG, 37200-900, Brazil.
Plant Physiol Biochem. 2023 Jan;194:335-344. doi: 10.1016/j.plaphy.2022.11.024. Epub 2022 Nov 24.
Zinc (Zn) and iron (Fe) are essential micronutrients for all living organisms and the major targets for crop biofortification. However, when acquired in excess quantities, Zn and Fe can be toxic to plants. In this study, we examined the interaction between Zn and Fe in soybean plants under various Zn and Fe treatments. While the level of Zn accumulation increased with increasing Zn supplies, Zn content greatly decreased with rising Fe supplies. Moreover, Zn uptake rates were negatively correlated with Fe supplies. However, Fe accumulation was not greatly affected by elevating Zn supplies. Excess Zn supplies were found to induce typical Fe deficiency symptoms under low Fe conditions, which can be counteracted by increasing Fe supplies. Interestingly, leaf chlorosis caused by excess Zn and low Fe supplies was not directly associated with reduced total Fe content but likely associated with deleterious effects of excess Zn. The combination of high Zn and low Fe greatly activates FRO2 and FIT1 gene expression in soybean roots. Besides, Zn-Fe interaction influences the activities of antioxidative enzymes as well as the uptake, accumulation, and homeostasis of other essential micronutrients, such as copper and manganese in soybean plants. These findings provide new perspectives on Zn and Fe interaction and on heavy metal-induced Fe deficiency-like symptoms.
锌（Zn）和铁（Fe）是所有生物必需的微量营养素，也是作物生物强化的主要目标。然而，当过量获取时，锌和铁会对植物产生毒性。在本研究中，我们研究了在不同锌和铁处理下大豆植株中锌和铁之间的相互作用。虽然锌积累水平随着锌供应的增加而升高，但锌含量随着铁供应的增加而大幅下降。此外，锌吸收速率与铁供应呈负相关。然而，铁积累并未受到锌供应增加的显著影响。发现在低铁条件下，过量的锌供应会引发典型的缺铁症状，而增加铁供应可以抵消这种症状。有趣的是，过量锌和低铁供应引起的叶片黄化与总铁含量降低没有直接关联，而可能与过量锌的有害影响有关。高锌和低铁的组合极大地激活了大豆根中FRO2和FIT1基因的表达。此外，锌 - 铁相互作用影响抗氧化酶的活性以及大豆植株中其他必需微量营养素（如铜和锰）的吸收、积累和稳态。这些发现为锌和铁的相互作用以及重金属诱导的缺铁样症状提供了新的视角。
