However, the line with the Vrn1h allele that has
Figure 4. Comparison of apex development in T. monococcum plants. (A–B and E) Winter G3116 (vrn1); (C and F) PI 306540 (Vrn1h); (D & G) PI 266844 (Vrn1f). (A) Continuous LD, vegetative stage. Under the same conditions lines with the dominant Vrn1h and Vrn1f alleles had already headed (not shown). (B, C, D) Continuous SD. (E, F, G) 10 weeks at SD and 4 weeks at LD (SD–LD). Note the more advanced development of the inflorescence in Vrn1f relative to vrn1 and Vrn1h in both SD and SD–LD. White bars represent 0.5 mm.
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the same intron insertion but no CArG-box mutation, showed no increase of VRN1 transcripts under SD. In addition, the lines with the Vrn1g allele (34-bp deletion) that have no insertion in the first intron show increased levels of VRN1 tran- scripts under SD (Figure 3A).