Transfer of Gaseous Iodine to Rice Plants

Abstract

Transfer rate of gaseous elemental iodine from the atmosphere to rice plants was investigated. The estimated transfer rates of iodine to rough rice and leaves, which were given as the ratios of iodine uptake rate per unit weight of plants to iodine concentration in the air, were approximately 0.08 to 0.1 and 2.0 cm³/g⋅sec, respectively. These values are concordant with those previously reported for other plants. Almost all iodine deposited on rough rice is maintained in the hulls and only about 10% of total iodine is contained in brown rice. The pattern of loss of iodine from rice plants are largely different among organs of the plants. Iodine concentration in leaves decreased exponentially with the half life of about 14 days, whereas that in rough rice seemed to depend only its weight. Migration of iodine in rice plants was barely perceptible.