Effect of organic acids on the growth of rice and wheat seedlings supplied with ammonium and nitrate.

Abstract

Using Norin No.41 of rice or Tohoku No.104 of wheat, effect of pyruvate, succinate and glycolate on the growth of seedlings supplied with ammonium or nitrate were studied. The results are summarized as follows : 1. Rice (Table 2 and 3) The growth of top, seminal root and crown root was promoted by the three organic acids. Ammonium enhanced the growth of top, but inhibited the growth of seminal and crown roots. Nitrate accelerated the growth of top, seminal root and crown root. In the mixture of each one of organic acids and either ammonium or nitrate, the growth of top was not affected, however, seminal root was facilitated. The growth of crown root was especially enhanced in the mixture of organic acids and ammonium. 2. Wheat (Table 4 and 5) The promoting effects were found on the top and seminal root in pyruvate and succinate treatments but not in glycolate. The growth of top was enhanced by nitrate, but seminal root was not affected by ammonium or nitrate. The growth of top was also progressed in case of the mixture of either pyruvate or succinated and ammonium, and, on the other hand, that of seminal root was promoted in the mixture of both ammonium and nitrate with every organic acid, excepting in combination of nitrate with glycolate. From above results, it was found that influences on the growth in accordance with these organic acids were greater in rice than in wheat, and the effect of glycolate on the growth of rice differed from that of wheat.