2026-10-07T11:11:52Z https://api.figshare.com/v2/oai

oai:figshare.com:article/33684427 2026-09-14T03:46:01Z category_26887 category_24391 item_type_3 month_year_09_2026

<b>Do plant strigolactones follow macroecological patterns? The seed-borne endomicrobiome shapes two global gradients in an invasive plant </b> Sebastián A. Reyes (23806147) Marco A. Molina-Montenegro (22807572) Biosecurity science and invasive species ecology Plant physiology Biogeography Biological invasions Clinal variation Holobiont Seed-borne endomicrobiome Symbiosis <p dir="ltr">Strigolactones are rhizosphere-signaling hormones known for roles in mycorrhizal recruitment, abiotic stress tolerance and defense, but their variation across a species' geographic range remains largely unexplored. We tested two competing macroecological predictions using strigolactone concentrations from 42 populations of the globally invasive <i>Taraxacum officinale</i>, comparing plants with an intact or an experimentally reduced seed-transmitted endomicrobiome. A cold-tolerance hypothesis predicts a U-shaped distribution with latitude, while an enemy-release hypothesis (EICA) predicts a monotonic decline with distance from the species' region of origin. Distance from the region of origin predicted strigolactone decline consistently in both hemispheres, and this decline was significantly steeper in plants with an intact than a reduced endomicrobiome. Latitude predicted strigolactone levels only in the Northern Hemisphere, where the endomicrobiome again amplified the response. These results indicate that enemy release, not cold tolerance, is the dominant driver of strigolactone variation in this species, and that the underlying decline is specific to the endomicrobiome-dependent component of strigolactone production. Our findings add a macroecological dimension to a hormone whose signaling role has mostly been examined through its biochemistry and physiology, with implications for how microbe-dependent chemical signals are reshaped during biological invasion.</p> 2026-09-14T03:46:01Z Dataset Dataset 10.6084/m9.figshare.33684427.v2 https://figshare.com/articles/dataset/_b_Do_plant_strigolactones_follow_macroecological_patterns_b_b_A_global_case_study_case_in_the_common_dandelion_b_/33684427 CC BY 4.0 Embargoed