In the presentation of part 1, we reported that blue-light and green-light showed the opposite effect on flowering timing in short-day plants and long-day plants. By the way, we already reported that combination treatment of GA_3 and SABA promoted flowering in long-day plants but not in short-day plants. So, we tested about the effect of combination treatment of light quality and plant hormons(GA_3+SABA) on flowering. The flower-promoting effect of GA_3+SABA treatment was recognized only in long-day plants. The efeect came out underblue-light and not under green-light.