Abstract
The extensive experiment on rice responses to its environmental conditions has been studied at a great number of agricultural experimental stations throu-ghout Japan since 1948. The analysis of these data gives many useful informations to both rice breeders and research workers on rice. This report is a part of this kind of analysis, especially from the standpoint of rice breeder. The analysis of variance on data which are derived from experiments in Tohoku, Hokuriku and Kanto districts shows us following interesting informations.