Figure 1.

Frequency distribution of flowering time in the F2 population derived from a cross between HK2 and its NIL carrying the spring allele for Vrn-H1 (NIL [Vrn-H1]) under field conditions. The 892 F2 plants could be classified into three types by the genotype of a causal gene for flowering time (PS [t]; A) as well as its candidate genes HvPhyC (A), Vrn-H1 (B), and HvCK2α (C). White, gray, and black rectangles indicate homozygote for HK2 allele, heterozygote, and homozygote for NIL (Vrn-H1) allele.