Lasiodiplodia theobromae as a Model Latent Pathogen: Molecular Mechanisms, Global Impact, and Sustainable Management.
TL;DR
A testable model wherein environmental triggers and host hormone balance converge temperature-regulated virulence gene expression to govern the endophyte-to-necrotroph transition is proposed.
Abstract
Lasiodiplodia theobromae (Botryosphaeriaceae) is a cosmopolitan ascomycete that endophytically colonizes over 500 plant species and switches to necrotrophy under host stress. In mango (Mangifera indica), it causes stem-end rot, dieback, gummosis, and collar rot, driving substantial pre- and postharvest losses worldwide. This review integrates five thematic areas: (i) multilocus phylogenetics (ITS, tef1-α, tub2, and rpb2) resolving cryptic species within the L. theobromae species complex; (ii) disease epidemiology centered on latent colonization of inflorescences and stress-triggered activation; (iii) molecular pathogenicity mechanisms, including secreted effectors, cell wall-degrading enzymes, fungal phytohormones, and regulatory small RNAs; (iv) multi-omics advances revealing expanded CAZyme and secondary metabolite biosynthetic gene clusters, plus emerging multi-class fungicide resistance (MBC, QoI, and DMI) driven by β-tubulin mutations, alternative oxidase upregulation, and CYP51 overexpression; and (v) sustainable biological control using Streptomyces, Bacillus, and Trichoderma strains, alongside host priming with hexanal or methyl jasmonate. We propose a testable model wherein environmental triggers (temperature and drought) and host hormone balance (ethylene and jasmonic acid-salicylic acid crosstalk) converge temperature-regulated virulence gene expression to govern the endophyte-to-necrotroph transition. Critical gaps include the limited genomic resources for mango-derived isolates, infection-stage dual RNA-seq, population genetics, and climate-informed epidemiological models. Future directions encompass CRISPR-enabled susceptibility gene editing, RNAi biocontrol, and integrated pest management tailored to this latent pathogen. [Formula: see text] Copyright © 2026 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
