α-amylase in germinating, decorticated barley—III : Effects of adding CCC and other chemical substances

Abstract

Chlorocholine chloride, CCC, has been shown to inhibit growth and the formation of α-amylase in germinating barley. The addition of gibberellic acid, GA 3, did not fully reverse the inhibition of growth caused by CCC, but α-amylase synthesis increased to the level found in grains cultured with GA 3 only. Thus CCC had a toxic effect on the embryo in addition to suppressing the endogenous formation of gibberellins. In the presence of GA 3 and large quantities of CCC α-amylase synthesis in barley was slow relative to the rate of enzyme formation with GA 3 only, but the rate of decline in enzyme was also retarded. Choline gave results generally similar to those produced by CCC, when applied to germinating barley. High levels of potassium sulphate slowed enzyme degradation but not synthesis in grain germinated with or without GA 3. Some twenty-three compounds were added to germinating barley in the presence and absence of gibberellic acid, and the results were interpreted in terms of varying damaging effects towards the endogenous production of gibberellins, embryo growth, and the system synthesizing α-amylase in the aleurone layer. The results suggest that choline, hordenine and other naturally occurring basic substances may regulate the endogenous synthesis of gibberellins in germinating barley.