Abstract
In this paper the mechanism of increment of chlorophyll content in leaves of rice plants was discussed, when sprayed with 2, 4-dichloro-6-(orthochloroanilino)-1, 3, 5-s-triazine (Triazine, Dyrene). Rice plants were cultivated in nutrient solutions deficient in N, Mg and both of them respectively. After 5 days they were transferred to the complete nutrient solution, and then sprayed with Triazine. The chlorophyll content was measured 2 days after spraying. The chlorophyll content in the leaves sprayed with Triazine increased several folds irrelevant to the prior nutritional treatment.
After spraying of Triazine, rice plants were continued to cultivate 2 days in the respective nutrient deficient solution and then transferred to the complete nutrient solution. After 2 days the chlorophlyl content of these leaves were measured. No effect of Triazine spraying was recognized in these cases.
As the effect of Triazine spraying on the chlorophyll content seemed to diminish in a few days, and as Triazine might be decomposed and utilized as a nitrogen source, the effects of spraying urea and ammonium sulfate on the chlorophyll content were compared to that of Triazine. The result indicated that the effect of Triazine was nearly equal to that of urea and larger than that of ammonium sulfate in terms of chlorophyll content.
The rate of chlorophyll decomposition was compared between the Triazine-sprayed and non-sprayed plants raised in complete nutrient solution.
When the plants were transferred to deionized water after the spraying, the chlorophyll content increased about 8% in the Triazine-sprayed leaves 2 days after the spraying. The rate of decomposition of chlorophyll, however, seemed to be the same between Triazine sprayed and control leaves, at least for 8 days.
