Physiological Studies on the Effects of Silicic Acid upon Rice Plants : X. Effects of silicic acid on the growth of rice plant under the high and low air temperature

Abstract

In order to know the effects of silicic acid on the growth of rice plant under the high and low air temperature conditions, the present study was planned as follows, that is, plot (N) in wich no silicic acid was supplied, plot (s) supplied with SiO2 10 ppm and plot (S) supplied with SiO2 100ppm were set up in each treatment of high air temperature (H), low air temperature (L) and control (C). The following result are obtained. In the rice plant grown under sufficient amount of silicic acid, the amounts of nitrogen, phosphorus and potassium absorbed, the accumulated amounts in the panicle of these elements, and the production and accumulation of total sugar and starch in the panicle were respectively larger than in the rice plant of N wich had been raised without SiO2. As a result of it, the production of dry matter of rice plant supplied with sufficient SiO2 was larger than that of rice plant without SiO2. The productions of dry matter of rice plant of HN and LN were especially inferior to those of other treatments. In the treatment H, C and L the weights of dry matter were proportionally increased to increasing amount of silicic acid supplied. In the treatment H and L the differences between the amounts of growth of rice plants in S and N were respectively larger than in the control. Accordingly, it was clearly recognized that the sufficient supply with silicic acid reduced the bad influences on the growth of rice plant under the high and low air temperature.