The first author reported transcription of the sd1 gene derived from Jukkoku . RT-PCR of root RNA showed that the 779 bp fragment derived from the sd1 locus was clearly cleaved into 613 bp and 166 bp fragments by PmaCI digestion on the SNP in Jukkoku_sd1, but there was no cleavage of the Sd1 locus in Koshihikari (Figure 5). This is the first evidence of the transcription of sd1, a defective gene of GA20ox-2. Accordingly, Jukkoku_sd1, which is substituted by only a single nucleotide against the 385 bp-deficient IR_sd1  and is actively transcribed, has no deteriorative effect on the panicle and may have a positive effect on panicle elongation by the overflow of nutrition due to culm reduction.