Enhancing consistency in arbuscular mycorrhizal trait-based research to improve predictions of function

Abstract

Arbuscular mycorrhizal (AM) fungi (phylum Glomeromycota) are obligate symbionts with plants influencing plant health, soil a(biotic) processes, and ecosystem functioning. Despite advancements in molecular techniques, understanding the role of AM fungal communities on a(biotic) processes based on AM fungal taxonomy remains challenging. This review advocates for a standardized trait-based framework to elucidate the life-history traits of AM fungi, focusing on their roles in three dimensions: host plants, soil, and AM fungal ecology. We define morphological, physiological, and genetic key traits, explore their functional roles and propose methodologies for their consistent measurement, enabling cross-study comparisons towards improved predictability of ecological function. We aim for this review to lay the groundwork for establishing a baseline of AM fungal trait responses under varying environmental conditions. Furthermore, we emphasize the need to include underrepresented taxa in research and utilize advances in machine learning and microphotography for data standardization.

Keywords: Ecosystem processes; Environmental adaptation; Functional diversity; Standardization; Symbiosis; Trait-based ecology.

Fig. 1

Visual representation of key arbuscular mycorrhizal fungal traits, highlighting their morphological (e.g., spore wall number, hyphal architecture), physiological (e.g., enzymes, poly-P, lipids), and genetic features (e.g., G + C content, genome size, homo- versus dikaryosis). The figure provides an overview to help readers connect these traits to their functional roles. Note that the illustration is not exhaustive and further details can be found in Table 1. Illustration created by Pedro M. Antunes using Procreate

Fig. 2

Illustration of various approaches to study AM fungal traits, which can be used either in the greenhouse or the field. Illustration created by Pedro M. Antunes using Procreate