Changes in beta-cyanoalanine synthase activity during stratification of Japanese apricot [Prunus mume] seeds
1999
Mizutani, F. (Ehime Univ., Matsuyama (Japan). Coll. of Agriculture) | Hirota, R. | Moon, D.G. | Bhusal, R.C. | Akiyoshi, H. | Amano, S. | Hino, A. | Kadoya, K.
Changes in beta-cyanoalanine synthase (CAS) activity and amygdalin content of Japanese apricot (Prunus mume Sieb. et Zucc.) seeds were monitored during stratification at different temperatures. When seeds were kept under moist conditions at 5, 10, 18, 24 and 30 degree C, beta-CAS activity increased at 5 and 10 degree C from the start to 20 and 40 days, respectively, followed by slight declines. The lower temperature was more efficient in the elevated activity. However, beta-CAS activity was gradually decreased at temperatures higher than 18 degree C. The higher the temperatures, the greater the activity declined. The content of amygdalin, major seed cyanogenic glycoside of Japanese apricot, seemed to be slightly declined at 5 and 10 degree C for a long stratification, but tended to increase slightly and then decreased at 24 and 30 degree C. Seeds germinated only at 5 degree C. Furthermore, whenever seeds kept at 24 degree C were transferred to 5 degree C, the beta-CAS activity increased and seeds germinated. Upon the transfer, amygdalin content seemed to be lowered compared with the control. Benzylaminopurine (BA) enhanced both seed germination and beta-CAS activity. Therefore, the beta-CAS activity is associated with cyanide metabolism in dormancy breaking of Japanese apricot seeds
显示更多 [+] 显示较少 [-]