THE EFFECT OF GIBBERELLIC ACID AND N-ETHYLMALEIMIDE ON AMYLASE ACTIVITY, ASCORBIC ACID, AND GLUTATHIONE IN GERMINATING BARLEY SEEDS

摘要

The effects of treating germinating barley seeds with gibberellic acid and N-ethylmaleimide alone and in combination were investigated. Gibberellic acid treatment had no effects on the levels of beta;-amylase, ascorbic acid, and glutathione but increased production of alpha;-amylase. N-Ethylmaleimide suppressed the levels of alpha;-amylase and glutathione and delayed the attainment of peak for beta;-amylase. In combining gibberellic acid and N-ethylmaleimide, the effect on alpha;-amylase of 4ensp;mMN-ethylmaleimide was completely reversed and that of 8ensp;mMN-ethylmaleimide was almost completely reversed. The combination of gibberellic acid and N-ethylmaleimide produced lower levels of glutathione than those for N-ethylmaleimide alone, and had some peculiar effects on the activity of beta;-amylase. It is concluded that the increase of alpha;-amylase activity in germinating barley by gibberellic acid is not produced through the effect of gibberellic acid on ascorbic acid ndash; glutathione system. There is, however, an indication that gibberellic acid does affect some mdash;SH sensitive systems.