Week 7: Border disputes

Fungal genet boundaries, contact-zone antagonism, and how far "territory" can stretch as a description of soil competition.

TB0815 · diorama S. Brandt, NHM Basel · CC BY 4.0

Dispatch 07

Date: 5 April 2027
Metaphor: Border disputes — contested territory and the recognition of who holds it
Phenomenon: Root and mycelial territoriality: competition for substrate between fungal genets, and self/non-self recognition at contact zones

Outline

a genet is one genetically distinct fungal individual, which can spread through soil far beyond any single visible fruiting body
where two different genets meet, competitive exclusion and visible antagonism at the contact zone is well documented
self/non-self recognition operates at these boundaries: compatible tissue can fuse, incompatible tissue rejects contact — the full genetic mechanism is deferred to week 10, where it is the week’s main phenomenon rather than a supporting one
root systems from different plants overlap and compete for the same nutrient patches, and a mycorrhizal partner can extend or contract that competitive reach on the plant’s behalf
“border dispute” fits the contest over a patch of soil; it fits less well as a claim that either side recognises the other’s claim as legitimate rather than simply failing to get past it