Abstract
It has been found that the relative growth of the root and shoot in rice plants (Oryza sativa L.) may be expressed by allometric formula, y=bxα, where x is the dry weight of shoot, and y the dry weight of root, while b and α are constants. The constant α represents, in this report, the ratio of the logarithmic growth rate of root over the logarithmic growth rate of shoot, and b the weight of the root when the shoot weighs one gram. The formula may also be written as log y=log b+α log x, so that when the measurements are plotted on a double logarithmic grid the points fall on a straight line. The value of α is therefore equivalent to the regression of log y on log x. As it did not vary greatly in any of the experiments with one exception of H2-S treatment the effect of treatment on the value of α may be supposed not to be so large. The value of α drops strikingly at respective heading stage showing minus value. It has also been shown that this formula can be applied to the results reported by many other investigators of root and shoot growth in rice plants, however the values of α were higher than those of the author's data.
