TraitMech

TraitMech › MORPHOLOGY

fungal branched absorbing structure formation

traitmech:000665 · CLASS · PROPOSED

A morphological phenotype in which an arbuscular mycorrhizal fungus forms localized, dichotomously branched groups of progressively finer hyphae, called branched absorbing structures, on its extraradical runner hyphae.

Trait evidence (2)

  • DOI:10.1046/j.1469-8137.1998.00199.x
    small groups of dichotomous hyphae formed by the extraradical mycelium of arbuscular mycorrhizal (AM) fungi.

    Bago et al. (1998), New Phytologist 139:375-388; contiguous defining phrase from the Summary, read in the primary publisher PDF. The publisher's later online date is not the study year. Methods, Results and selected Discussion passages were read; actual figures were not inspected after screenshot/download failures. DAOM197198, named Glomus intraradices in this paper, formed BAS with non-transformed tomato cv. Vendor roots. Results distinguish progressively finer dichotomous branches from aborted short branches. Formation took about seven days under the tested conditions, not a universal lifespan. Some spore-associated BAS persisted and produced spores. Negative axenic and unsuccessful monoxenic cultures constrain these experiments, not every possible asymbiotic condition. The proposed absorptive role is not a direct uptake assay.

  • DOI:10.1093/pcp/pcz122
    highly branched hyphae called branched absorbing structures (BAS) differentiate on the runner hyphae

    Kameoka et al. (2019), PMID:31241164; Introduction clause before the Figure 1 citation, exact-matched in directly retrieved publisher HTML. Abstract, Introduction, Results, Discussion and Methods were read. Actual Figure 1C/G and its caption were inspected: six-week Rhizophagus irregularis DAOM197198 carrot hairy-root cocultures supply direct BAS morphology evidence. The RNA-seq comparison is not a direct uptake assay or causal perturbation. Runner-hypha and spore samples contained some BAS; negligible contamination influence was the authors' inference, not measured absence. Their historical no-direct-uptake-evidence statement is not a present-day knowledge claim. Remaining figure images and supplementary spreadsheet contents were not inspected.

Provenance

Identifier source
TraitMech local identifier
Definition source
DOI:10.1046/j.1469-8137.1998.00199.x

Parent traits (1)

kg-microbe context

No kg-microbe node embedding matched this record in the 2026-04-25 deepwalk.

Canonical examples (1)

Organisms cited as exemplars of this trait. Taxon ids are NCBITaxon and link out to the NCBI record.

  • Rhizophagus irregularis NCBITaxon:588596 DOI:10.1093/pcp/pcz122 DAOM197198 from Premier Tech in six-week carrot hairy-root coculture, Methods and actual Figure 1C/G. The Canadian GINCO catalogue https://agriculture.canada.ca/en/agricultural-science-and-innovation/agriculture-and-agri-food-research-centres-and-collections/glomeromycota-vitro-collection-ginco/catalogue-arbuscular-mycorrhizal-fungi-strains-available-glomeromycetes-vitro-collection lists DAOMC197198, herbarium DAOM197198/181602, MUCL43194, Pont-Rouge in Quebec, a tree plantation, and collectors/isolators C. Plenchette and V. Furlan. These collection fields support field-isolate origin and are not a synthesized evidence snippet. NCBI Taxonomy confirms species 588596 and its strain 747089, Rhizophagus irregularis DAOM 181602=DAOM 197198. The transformed carrot host does not imply an engineered fungus. This is a culture-qualified observation, not independent reidentification or evidence for every strain and condition.

Discussions and Knowledge Gaps (2)

Open questions attached to this trait. Seeded by just knowledge-gap-scan and curated; see the corpus-wide index.

Resolve a closer parent while preserving BAS morphology scope.

CURATION TODO OPEN fungal-bas-scope-and-hierarchy · raised by codex · 2026-10-07

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

Use phenotype METPO:1000059. Branched shaped METPO:1000687 and filament shaped METPO:1000674 classify cell shape, not this differentiated extraradical architecture. Mycelial growth traitmech:000074 is explicitly bacterial. Fungal arbuscule formation traitmech:000664 concerns structures within living plant cells; the historical arbuscule-like structures name does not make BAS intracellular arbuscules. Appressorium formation traitmech:000659 concerns penetration structures, hyphal anastomosis traitmech:000605 fusion, and pseudohyphal growth traitmech:000653 budding-cell chains. Bago et al. also distinguish pre-infection fan-like structures and aborted short branches. No exact synonyms, structure xrefs, SSSOM equivalences or disjoint-organism claims are asserted. A closer morphology parent needs upstream review.

Separate formation from absorption, host dependence and mechanism.

KNOWLEDGE GAP OPEN fungal-bas-formation-and-function · raised by codex · 2026-10-07

Not yet attached to a section of this record — a curator sets attaches_to (e.g. causal_graphs#some_edge) so the gap shows beside the mechanism it concerns.

Absorbing is the established structure name, not a required flux measurement. Do not infer mineral uptake, obligatory host contact, universal timing, inevitable degeneration or sporulation from morphology. Bago et al.'s host-dependence interpretation describes their tested media; later asymbiotic growth work DOI:10.1073/pnas.2006948117 remains a BAS-specific full-text/figure follow-up, not counted BAS evidence here. Transcriptional associations in Kameoka et al. do not identify a causal formation pathway. Their in vitro host system also does not establish expression patterns in soil-grown intact plants. A protein-resolved graph is deferred pending direct perturbation evidence and authority-verified protein anchors; it is not claimed biologically absent.

Curation history

  1. · MINTED_TRAITMECH_ID · codex

    Added fungal BAS formation with two primary DOI-backed snippets and a culture/provenance-qualified DAOM197198 example. Ignored-and-hidden novelty and main/worktree/open-PR checks support local ID 000665 and v541 block 1061800-1061899. Kept morphology separate from uptake, host-dependence extrapolation and causal mechanisms.

Recorded curation sessions

  • · codex
    • CREATE — Add source-qualified fungal BAS formation

      Added traitmech:000665 as PROPOSED MORPHOLOGY with primary DOI:10.1046/j.1469-8137.1998.00199.x and DOI:10.1093/pcp/pcz122 snippets, and a DAOM197198 culture-qualified Rhizophagus irregularis example supported by inspected microscopy, collection provenance and NCBI taxonomy. Reserved v541/METPO:1061800 in 1061800-1061899 after ignored-and-hidden current-main/worktree and paginated immutable-head PR checks. Kept uptake, universal host dependence and protein mechanisms out of the definition; two discussions remain OPEN. Writer dry run and all 20 focused writer tests passed before application. No existing trait was edited.

    Read this curation session