Mycorrhizas are mutually beneficial associations between soil-borne fungi and plant roots. Mycorrhizal fungi provide their host plant with essential nutrients in exchange for sugars and/or lipids. Traditionally, transport and translocation of macronutrients, including nitrogen and phosphorus, throughout the fungal mycelium and towards the host plant are well studied. However, the regulation of nutrient exchange and their contribution in the morphogenesis and development of mycorrhizas remains unclear. In this Opinion, we argue that adding micronutrients in the current models of symbiotic transport is essential to fully understand the establishment, maintenance, and functioning of mycorrhizal associations. Homeostatic mechanisms at the cellular level and the first transport proteins involved have been recently documented for zinc (Zn) in arbuscular mycorrhizal, ectomycorrhizal, and ericoid mycorrhizal fungi. Mycorrhizal plants benefit from an improved Zn status in control conditions and are better protected when environmental Zn availability fluctuates. These recent progresses are paving the way for a better understanding of micronutrient allocation in mycorrhizas. Revising our vision on the role of micronutrients, particularly of Zn, in these interactions will allow a better use of mycorrhizal fungi in sustainable agriculture and forestry, and will increase management practices in waste land, as well as in agricultural and natural ecosystems.

菌根是土壤传播真菌和植物根系之间的互利关联。菌根真菌为宿主植物提供必需的营养，以换取糖和/或脂质。传统上，对包括氮和磷在内的大量营养素在整个真菌菌丝体中以及向寄主植物的运输和转运进行了深入研究。然而，营养交换的调节及其在菌根的形态发生和发展中的作用仍不清楚。在本意见中，我们认为，在目前的共生运输模型中添加微量营养素对于充分了解菌根协会的建立，维持和功能至关重要。最近，在丛枝菌根，外生菌根和类固醇菌根真菌中，锌（Zn）在细胞水平上的稳态机制和所涉及的第一个转运蛋白已有报道。在控制条件下，菌根植物可从改善的锌状态中受益，并且当环境锌的利用率波动时，可以更好地保护菌根。这些最新进展为更好地了解菌根中微量营养素的分配铺平了道路。修改我们对微量营养素（特别是锌）在这些相互作用中的作用的看法，将使菌根真菌在可持续农业和林业中得到更好的利用，并将增加荒地以及农业和自然生态系统的管理实践。在控制条件下，菌根植物可从改善的锌状态中受益，并且当环境锌的利用率波动时，可以更好地保护菌根。这些最新进展为更好地了解菌根中微量营养素的分配铺平了道路。修改我们对微量营养素（特别是锌）在这些相互作用中的作用的看法，将使菌根真菌在可持续农业和林业中得到更好的利用，并将增加荒地以及农业和自然生态系统的管理实践。在控制条件下，菌根植物可从改善的锌状态中受益，并且当环境锌的利用率波动时，可以更好地保护菌根。这些最新进展为更好地了解菌根中的微量营养素铺平了道路。修改我们对微量营养素（特别是锌）在这些相互作用中的作用的看法，将使菌根真菌在可持续农业和林业中得到更好的利用，并将增加荒地以及农业和自然生态系统的管理实践。