Dark Septate Endophytes: Important Partners of Mycorrhizal Fungi and Their Genomic Signatures for Adaptation

doi:10.7525/j.issn.1673-5102.2025.03.006

Abstract

Abstract:

Dark septate endophytes（DSEs） constitute an important component of root-associated mycobiome and typically develop microsclerotia-like structures in cortical cells. Generally， DSEs perform functions similar to those of mycorrhizal fungi in promoting plant growth， nutrient uptake and stress tolerance. Under certain extreme environments， the abundance of DSEs often exceeds that of mycorrhizal fungi. In this review article， we first summarized the species diversity， basic biological traits and eco-physiological functions played by DSEs， an important component of root-associated mycobiome. We then mainly focused on the advances concerning mechanisms underlying plant-DSEs mutualism as well as genomic signatures and evolutionary adaptation of DSEs. Together， our understanding of more adaptive potentials of DSEs and their extended effects on improving plant abiotic tolerance emerged. Promisingly， the development of robust DSE inoculants used for ecological restoration of soils and improvement of plant productivity in agro-forestry systems under stressful environment was briefly discussed.

Key words: dark septate endophytes, mycorrhizal fungi, mutualistic relationships, population divergence

CLC Number:

Q948.12

Zhongfeng LI, Zhiyong ZHU, Zhilin YUAN. Dark Septate Endophytes: Important Partners of Mycorrhizal Fungi and Their Genomic Signatures for Adaptation[J]. Bulletin of Botanical Research, 2025, 45(3): 352-360.

Figures/Tables 1

References 70

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