Nitrogen dioxide accelerates flowering without changing the number of leaves at flowering in Arabidopsis thaliana.

A negative correlation has consistently been reported between the change in flowering time and the change in leaf number at flowering in response to environmental stimuli, such as the application of exogenous compounds, cold temperature, day length and light quality treatments in Arabidopsis thaliana (Arabidopsis). However, we show here that the application of exogenous nitrogen dioxide (NO2) did not change the number of rosette leaves at flowering, but actually accelerated flowering in Arabidopsis. Furthermore, NO2 treatment was found to increase the rate of leaf appearance. Based on these results, reaching the maximum rosette leaf number earlier in response to NO2 treatment resulted in earlier flowering relative to controls.