identifier: traitmech:000667 label: fungal Hartig net formation definition: A morphological phenotype in which a fungus forms an intercellular hyphal network, called a Hartig net, within a plant root. definition_source: DOI:10.1111/nph.17940 trait_category: MORPHOLOGY term_kind: CLASS mapping_status: PROPOSED parent_traits: - METPO:1000059 evidence: - reference: DOI:10.1111/nph.17940 snippet: hyphae grow between rhizodermal cells, forming an intraradical, apoplastic hyphal network, the so-called Hartig net notes: Zhang et al. (2022; online 23 December 2021), Introduction, second paragraph, directly read publisher HTML. The contiguous clause defines the intercellular architecture, separately from the external mantle. Main text and captions were read; actual figure images and supplements were not inspected. RNAi reductions in network depth or colonized lateral-root frequency are not complete formation loss. The corrected LbGH28A cDNA must be compared with the reported reference sequence before protein grounding; no accession-level equivalence is asserted. - reference: DOI:10.1111/nph.15113 snippet: a loose hyphal weft has been formed between two rhizodermal cells to differentiate an intraradicular hyphal network, the so-called Hartig net notes: 'Zhang et al. (2018), Introduction, printed/physical p. 1, early-view author PDF: https://ri.conicet.gov.ar/bitstream/handle/11336/117651/CONICET_Digital_Nro.2f10e756-314d-4409-8829-81a4798588b0_A.pdf?isAllowed=y&sequence=2 The contiguous clause was exact-matched after joining PDF line wraps and hyphenated line breaks, and visually checked. Main text and actual Figure 2 on p. 7 were inspected. Panel d shows wild-type S238N root sections; panel c retains a thinner RNAi A4 network, not its absence. Other images and supplementary contents were not inspected.' - reference: DOI:10.1007/s00572-014-0590-7 snippet: Hartig net around epidermal cells para-epidermal in one row; hyphal cells roundish to cylindrical. notes: 'Kuehdorf et al. (2015; online 2014), Results, Anatomical characters of longitudinal section, printed p. 112 / physical p. 4: https://d-nb.info/1192098684/34 Complete contiguous descriptive sentence, exact-matched and visually checked. Main text through Discussion and actual Figure 3 on p. 114 were read. Panels e-f distinguish the Hartig net from intracellular hyphae in field-collected Leotia cf. lubrica-Comarostaphylis arbutoides roots. Anatomy was restricted to subgroup e; it does not identify every Leotia sample or the separately observed fruit bodies. No species-level canonical example or nutrient flux is inferred. Other figure images were not inspected.' canonical_examples: - taxon_id: NCBITaxon:29883 taxon_label: Laccaria bicolor reference: DOI:10.1111/nph.15113 note: Wild-type S238N, not an RNAi line or its haploid S238N-H82 progeny. Zhang (2018) Figure 2d documents the Hartig net in hybrid poplar INRA 717-1-B4 roots three weeks after contact; Methods specifies low-glucose Pachlewski medium. The laboratory provenance page https://mycor.iam.inrae.fr/IAM/?page_id=4555 traces S238N to a 1976 Crater Lake, Oregon fruitbody collection under Tsuga mertensiana. NCBI EFetch confirms species 29883 and child strain 486041 S238N-H82; the child is not substituted for the experimental culture. This qualified example is not independent reidentification or evidence for all strains and conditions. discussions: - discussion_id: fungal-hartig-net-scope-and-hierarchy prompt: Resolve a closer morphology parent without collapsing root interfaces. kind: CURATION_TODO status: OPEN rationale: Use active phenotype METPO:1000059 under quality METPO:1000188. METPO:1000198 mycorrhization is obsolete. Branched shaped METPO:1000687 concerns cell shape; mycelial growth traitmech:000074 is explicitly bacterial. Arbuscule formation 000664 and peloton formation 000666 concern intracellular architectures; BAS formation 000665 is extraradical. Haustorium formation 000663 is not asserted exact, broader or disjoint. Ecological symbiosis, mutualism and endosymbiosis are not this network morphology. Arbutoid usage is directly supported above. The directly retrieved PubMed abstract for DOI:10.1007/s00572-004-0305-6 (PMID:15490255) also describes paraepidermal Hartig nets in field-collected Monotropa uniflora and Pterospora andromedea roots; its full text and figures remain unread, and no fungal taxon is inferred. The label is not restricted to one mycorrhizal category, root cell layer or host species. No exact synonyms, structure xrefs or SSSOM equivalences are asserted; a bare Hartig net names a structure, not its formation. posed_by: codex posed_date: '2026-10-07' - discussion_id: fungal-hartig-net-mechanism-and-culture-identity prompt: Keep morphogenesis, symbiotic function and sequence identity separate. kind: KNOWLEDGE_GAP status: OPEN rationale: No universal nutrient-transfer rate, mutualistic outcome or cell-wall mechanism is part of the definition. Native RNAi perturbations are evidence leads, not proof that the entire network is absent; heterologous and purified-protein assays are separate. DOI:10.1111/nph.18358, directly read main text and actual Figures 3 and 8, reports shallower RNAi networks and deeper overexpression networks despite lower overall ectomycorrhizal frequency. Its T89 host is not INRA 717-1-B4, and Figure 8a/c are schematics. A causal graph is deferred pending authority-verified proteins and sequence-to-culture links, not because mechanisms are biologically absent. Keep S238N distinct from H82 reference/progeny material. The laboratory history calls an Oregon-derived antecedent S238-O, whereas DOI:10.7150/jgen.130158 assigns S238O to Quebec; those source-specific aliases are not silently equated. posed_by: codex posed_date: '2026-10-07' curation_history: - timestamp: '2026-10-07T18:15:22Z' curator: codex action: MINTED_TRAITMECH_ID changes: 'Added fungal Hartig net formation with three DOI-backed snippets and a qualified wild-type S238N example. Ignored-and-hidden novelty and main/worktree/pending-PR checks support 000667, v543 and block 1062000-1062099; BAS #1788 and peloton #1791 retain their separate reservations. Kept intercellular architecture separate from nutrient transfer, intracellular structures and unverified protein mechanisms.' llm_assisted: true