Prasad T K, Cline M G
Department of Botany, Ohio State University, Columbus 43210, USA.
Plant Sci. 1987;49:175-9. doi: 10.1016/0168-9452(87)90038-0.
Ethylene evolution resulting from the gravity stress of shoot inversion appears to induce the release of apical dominance in Pharbitis nil (L.) by inhibiting elongation of the inverted shoot. It has been previously demonstrated that this shoot inversion release of apical dominance can be prevented by promoting elongation in the inverted shoot via interference with ethylene synthesis or action. In the present study it was shown that apical dominance release can also be prevented by promoting elongation of the inverted shoot via treatment with gibberellic acid (GA3). A synergistic effect was observed when AgNO3, the ethylene action inhibitor, was applied with GA3. Both GA3 and AgNO3 increased ethylene production in the inverted shoot. These results are consistent with the view that it is ethylene-induced inhibition of elongation and not any direct effect of ethylene per se which is responsible for the outgrowth of the highest lateral bud.
由茎倒置的重力胁迫导致的乙烯释放似乎通过抑制倒置茎的伸长来诱导牵牛（Pharbitis nil (L.)）顶端优势的解除。此前已经证明，通过干扰乙烯合成或作用来促进倒置茎的伸长，可以防止这种由茎倒置引起的顶端优势解除。在本研究中发现，用赤霉素（GA3）处理促进倒置茎的伸长，也可以防止顶端优势的解除。当乙烯作用抑制剂硝酸银（AgNO3）与GA3一起使用时，观察到了协同效应。GA3和AgNO3都增加了倒置茎中的乙烯产量。这些结果与以下观点一致，即导致最高侧芽生长的是乙烯诱导的伸长抑制，而非乙烯本身的任何直接作用。
