The rice variety, Nongkwang was used iu two factorial experiments with the combination of 15 ㎏ and 20 ㎏ of H per 10 a, 3 levels of P_2O_5 (0,4 and 8 ㎏ per 10 a) and 4 levels of potash (0,2,4 and 8 ㎏ per 10 a) in the reclaimed soil areas containing 0.48% of the average salt content througrout the year (0.67% at the end of April).
The absorption of N, K and Ca was accelerated by increased N applications. The absorption of P itself was not enhanced by the increased application of P_2O_5 but the absorption of K_2O reduced the absorption of Mg was affected. The increased application of K_2O reduced the absorption of Si and seemed to increase the content of carbohydrate in the rice plants.
Twenty ㎏ of N and 4 ㎏ of P_2O_5 per 10 a produced satisfactory yields of rough rice, potash applications are ineffective in this experiment on rice grain production.
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