Molecular profiling of chemical signals enhancing plant invasion by
shaping mutualistic associations
Abstract
Chemical signals are crucial in mediating ecological and evolutionary
adaptation of plants to their environments. Invasive plants can release
distinct secondary metabolite mixtures in their new ranges, enhancing
their mutualistic interactions and improving their performance, but
genetic mechanisms of such adaptations are unexplored. We used
Triadica sebifera plants to investigate evolutionary changes in
chemical signals (flavonoids and strigolactones) that enhance arbuscular
mycorrhizal (AM) fungal associations. We found plants from invasive
populations produced higher concentrations of the flavonoid quercetin
and the strigolactone 5-deoxystrigol, and had higher AM fungal
colonization rates and biomass, relative to those from native
populations. Also, applications of either chemical increased AM fungal
colonization. Higher expression of genes in flavonoid (FLS) and
strigolactone (CCD8) biosynthesis pathways that increased levels
of quercetin and 5-deoxystrigol, respectively, were confirmed. These
results provide insights into genetic mechanisms that contribute to
higher AM fungal colonization and plant invasion success.