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  • The genetic architecture of floral trait divergence between hummingbird‐ and self‐pollinated monkeyflower ( Mimulus ) species

This content will become publicly available on December 19, 2025

Title: The genetic architecture of floral trait divergence between hummingbird‐ and self‐pollinated monkeyflower ( Mimulus ) species
Summary Pollination syndromes are a key component of flowering plant diversification, prompting questions about the architecture of single traits and genetic coordination among traits. Here, we investigate the genetics of extreme floral divergence between naturally hybridizing monkeyflowers,Mimulus parishii(self‐pollinated) andM. cardinalis(hummingbird‐pollinated).We mapped quantitative trait loci (QTLs) for 18 pigment, pollinator reward/handling, and dimensional traits in parallel sets of F2hybrids plus recombinant inbred lines and generated nearly isogenic lines (NILs) for two dimensional traits, pistil length and corolla size.Our multi‐population approach revealed a highly polygenic basis (n = 190 QTLs total) for pollination syndrome divergence, capturing minor QTLs even for pigment traits with leading major loci. There was significant QTL overlap within pigment and dimensional categories. Nectar volume QTLs clustered with those for floral dimensions, suggesting a partially shared module. The NILs refined two pistil length QTLs, only one of which has tightly correlated effects on other dimensional traits.An overall polygenic architecture of floral divergence is partially coordinated by genetic modules formed by linkage (pigments) and likely pleiotropy (dimensions plus nectar). This work illuminates pollinator syndrome diversification in a model radiation and generates a robust framework for molecular and ecological genomics.  more » « less
Award ID(s):
1350935 2421658 2319721
PAR ID:
10571514
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
New Phytologist
Volume:
245
Issue:
5
ISSN:
0028-646X
Format(s):
Medium: X Size: p. 2255-2267
Size(s):
p. 2255-2267
Sponsoring Org:
National Science Foundation
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