Table I. Catalog of genes that segregate for allelic variation affecting flowering time plasticity.

For brevity, when orthologous relationships are clear, the name of the homologous gene in Arabidopsis is provided instead of species-specific nomenclature. Note that the pseudo-response regulator gene that causes the presence/absence of a vernalization requirement in beet is more closely related to those that affect photoperiod response than to those that affect the vernalization response in grasses.

Cue	Form of Variation	Gene or Gene Class	Species
Photoperiod	Response type	TERMINAL FLOWER1	Rose, strawberry
	Response magnitude	Phytochrome A	Soybean
		AP2-like transcription factor	Soybean
		GIGANTEA	Soybean
		EARLY FLOWERING3	Pea, lentil, barley
		Pseudo-response regulator	Barley, rice, maize
		FLOWERING LOCUS T	Sunflower, soybean, sorghum, Arabidopsis
Vernalization	Presence/absence	FRIGIDA	Arabidopsis
		FLOWERING LOCUS C	Arabis alpina
		Pseudo-response regulator	Wheat, barley, beet
	Duration of chilling necessary or response magnitude	FLOWERING LOCUS C	Arabidopsis, Arabis alpina, multiple Brassica spp., Capsella rubella
Temperature	Response magnitude	FLOWERING LOCUS M	Arabidopsis
		FRIGIDA	Arabidopsis
		FLOWERING LOCUS T	Arabidopsis