赤豆种子萌发中酰脲累积动态及若干碳氮化合物对其形成的影响

赤豆种子萌发中,幼苗迅速合成酰脲,萌发第4d达到最大值.谷氨酰胺和甘氨酸促进尿囊素合成,谷氨酸和天冬酰胺对尿囊素合成影响较小.外源铵促进幼苗合成尿囊素.三羧酸循环的部分中间产物(特别是琥珀酸或延胡索酸)或高浓度的乙醛酸(6-10 mmol/L)不同程度地抑制幼苗的尿囊索合成.

The Accumulation of Ureide and Effect of Some Nitrogenous and Carbonic Compounds in Germinating Seedlings of Adzuki Bean

Adzuki bean (Vigna angularis ) seedlings were analyzed quantitatively for ureidc, allantoin, allantoic acid content over a period of six days. The results showed marked accumulation of ureide (both allantoin and allantoic acid) in seedlings during the germination of adzuki bean. Ureide content in seedlings reached a plateau on the forth day of the germination. Several compounds respectively included in the growth medium were tested for their ability to affect the synthesis of allantoin, allantoic acid in seedlings. Repression of allantoin synthesis was observed with tricarboxylic acid cycle intermediates, especially with succinate or fumarate. Inhibition of high concentration of glyoxylate (6-10 mmol/L) on the allantoin synthesis was also found. Glycine or glutamine stimulated allantoin synthesis, but glutamate or asparagine did not show any significant effect. Exogenous ammonium promoted allantoin synthesis, which may be a response to ammonium toxification during the germination of adzuki bean.