identifier: traitmech:000665 label: fungal branched absorbing structure formation definition: 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. definition_source: DOI:10.1046/j.1469-8137.1998.00199.x trait_category: MORPHOLOGY term_kind: CLASS mapping_status: PROPOSED parent_traits: - METPO:1000059 evidence: - reference: DOI:10.1046/j.1469-8137.1998.00199.x snippet: small groups of dichotomous hyphae formed by the extraradical mycelium of arbuscular mycorrhizal (AM) fungi. notes: 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. - reference: DOI:10.1093/pcp/pcz122 snippet: highly branched hyphae called branched absorbing structures (BAS) differentiate on the runner hyphae notes: '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.' canonical_examples: - taxon_id: NCBITaxon:588596 taxon_label: Rhizophagus irregularis reference: DOI:10.1093/pcp/pcz122 note: 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: - discussion_id: fungal-bas-scope-and-hierarchy prompt: Resolve a closer parent while preserving BAS morphology scope. kind: CURATION_TODO status: OPEN rationale: 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. posed_by: codex posed_date: '2026-10-07' - discussion_id: fungal-bas-formation-and-function prompt: Separate formation from absorption, host dependence and mechanism. kind: KNOWLEDGE_GAP status: OPEN rationale: 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. posed_by: codex posed_date: '2026-10-07' curation_history: - timestamp: '2026-10-07T14:21:36Z' curator: codex action: MINTED_TRAITMECH_ID changes: 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. llm_assisted: true