What are karrikins and how were they ‘discovered’ by plants?

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Waters MT, Scaffidi A, Moulin ALY, Sun YK, Flematti GR, Smith SM. A Selaginella moellendorfii ortholog of KARRIKIN INSENSITIVE2 functions in Arabidopsis development but cannot mediate responses to karrikins or strigolactones. Plant Cell. 2015;27:1925–44.

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