This communication reports the rate of lamina inclination in intact plants under field condition and in excised leaves under experimental condition with various varieties, Japonica, Indica and dwarf types, of rice. Average rate of lamina inclination was 1.6 degrees per day in the intact rice plants at one month after planting. No difference in the rate was obtained among thirteen varieties used. In the intact plants the terminal leaves indicated average inclination rate of 1.3 degrees per day immediately after heading, but great difference was observed in the varieties used. The variety exhibiting the most rapid inclination rate is Te-Tep showing 4.1 degrees per day and the least rate is Jukkoku showing 0.2 degrees per day. From these results the gene control for lamina inclination may by supposed to exert conspicuously in the terminal leaves. In the leaves excised from etiolated rice seedlings, the variety which inclination rate is specially affected by IAA was found in Indica type. Further the inclination rate without IAA was striking in Vialone nano. From such experimental results, it will be effective to employ the rice leaves of Indica type in the new experimental method as established in the previous paper.
