Abstract:

Phosphorus (P) is an essential macronutrient for plant growth and development, and its bioavailability has a profound impact on the structure and function of ecosystems. Most plants form symbiotic associations with either arbuscular mycorrhizal (AM) fungi or ectomycorrhizal (ECM) fungi, which can significantly enhance their ability to acquire and utilize P. Although numerous studies have explored the differences in P acquisition and utilization strategies between AM and ECM plants, few have systematically synthesized these strategies. In this paper, we comprehensively review the P acquisition and utilization strategies from four perspectives: root morphology and architecture, root physiological traits, root-microbe interactions, and P resorption efficiency. It is concluded here that there exist significant differences in P acquisition and utilization strategies between AM and ECM plants. Specifically, AM plants usually form a mutually beneficial relationship with microorganisms that rapidly mineralize organic matter, have a limited extracellular enzyme secretion capacity, and prefer to absorb inorganic P, therefore adopting an “acquisition strategy”. In contrast, ECM plants have a strong ability to secrete extracellular enzymes and other secretions that enable them to utilize organic P, and therefore adopt a “conservation strategy”. Finally, this review proposes six research directions that need to be addressed to overcome current limitations in the future research. Overall, this review not only deepens our theoretical understanding of mycorrhizal-mediated P cycling processes, species coexistence, and productivity maintenance mechanisms, but also provides theoretical guidance for species selection, species configuration, and nutrient management in agricultural and forestry production and ecological restoration practices.

Key words: phosphorus acquisition strategies, arbuscular mycorrhiza, ectomycorrhiza, root trait, mycorrhizal trait, root exudate, microorganism