Abstract
We isolated the orthologues of WUS, STM and FUL (PnWUS1, PnSTM1, PnFUL1, respectively) in Pharbitis nil., a very sensitive plant for short-day treatment, aiming to reveal the control mechanism of early stage of flowering. The analysis by in situ hybridization in the shoot apical meristem showed that expression patterns of 3 genes were reminiscent of those observed for each orthologues in other plants. The quantitative analysis using RT-PCR showed that PnFUL1 mRNA was already accumulated in the flower induced SAM 10 times higher than that of the SAM without flower induction at the end of the 16 hours inductive dark span. In contrast, accumulations of PnWUS1 mRNA and PnSTM1 mRNA in the SAM were not significantly influenced by the dark treatment, at least within the 48 hours after the end of the dark span. The expected flowering mechanism of Pharbitis nil. will be discussed.
