Effects of Silicic Acid Absorbed from the Surface of the Leaves upon the Paddy Rice Plant Growth

[摘要] The experiment was made as to what would be the effect of silicic acid upon the growth of rice plants cultured without supply of silica, when it was applied through their leaf blades. The experiment was designed as follows: Plot non-Si: Rice plants were cultured without supply of silica. Plot spray: Na2SiO3 solution (0.1-0.2 ppm, Aug. 23-Sept. 27) was sprayed every other day on the surface of top of the rice plants cultured under the same conditions as rice plants of plot non-Si. Plot Si: Na2SiO3 was added in the culture solution. The results obtained were as follows: The rice plants of plot spray were superior to those of the other two plots in the following points; plant height, leaf number, stem number, panicle number, and dry matter weight at harvest time (fig. 1∼5). Contents and percentages of P2O5 in the whole plant and each of its organs (except its root) of plot spray were larger than in those of plot non-Si (fig. 7). Total N and P2O5 in the rice plant of plot spray were translocated to culms more smoothly than in those of plot non-Si, but not smoothly to panicles (fig. 6∼7). The serious differences of percentages of total N and K2O among three plots were not found (fig. 6, 8). The number of silicified cells in a leaf blade of the rice plant of plot spray was larger than that of the plant of plot non-Si (table 1), which proves that silica was absorbed in the leaves. Generally, the growth of the rice plant of plot spray were superior than that of the other two plots. The absorbtion of N, P, K through the roots of the rice plants of plot spray was easily; so was the translocation of N, P in the rice plants of plot spray. It is recognized that silicic acid absorbed from the surface of the leaf blade positively affected on the growth and physiological activity of the rice plant. It has need of silicic acid for the good growth of the rice plant.

[学科分类] 农业科学（综合）