Studies on the Uptake of $Sr^{90}$ with the Growth of Rice Plant

A Pot experiment was conducted to study the uptake of by rice plants in five different types of paddy soils and its distribution in these plants as a function of the age of the rice. The uptake of by rice plants increased with the growth of the aboveground mass of the plants from the planting period, but content per unit of dry matter decreased as the organic mass of the plants increased during the vegetative growing period, except for the time of ripening. The content of Ca and in rice plants was higher in the stem and leaves than in grain parts in general. However, Ca content was decreased in the stem and increased in the grain part with the growth of the rice plant ; but content was increased in the leaves and decreased in the stem and grain parts.