Rehm M M, Cline M G
Department of Botany, The Ohio State University, Columbus, Ohio 43210.
Plant Physiol. 1973 May;51(5):946-8. doi: 10.1104/pp.51.5.946.
An angular position-sensing transducer was used to make continuous measurements of acid-induced elongation of Avena sativa coleoptile segments. Elongation rates at pH 4.5 (5 mm succinate buffer) were about 5-fold greater than those at pH 6.0. Buffered 0.1 mm abscisic acid produced a partial decrease of the growth rate. Pretreatments with abscisic acid buffered at pH 6.0 usually caused a further reduction of the elongation response when the coleoptile segments were subsequently placed in buffer at pH 4.5 containing abscisic acid. Abscisic acid did not completely prevent the pH effect in any of these experiments, and the brief latent period of the pH response was not affected by abscisic acid treatments. At pH 4.5, where the inhibitory effect of ABA was maximum, low pH-induced elongation was also inhibited by KCN and HgCl(2). These results suggest that pH-(4.5) induced elongation in this system may be dependent on some metabolic processes and that abscisic acid-induced inhibition of this elongation may involve an interaction with these processes.
使用角位置传感换能器对酸诱导的燕麦胚芽鞘切段伸长进行连续测量。在pH 4.5（5 mM琥珀酸盐缓冲液）下的伸长率约为pH 6.0下的5倍。0.1 mM缓冲脱落酸使生长速率部分降低。当胚芽鞘切段随后置于含脱落酸的pH 4.5缓冲液中时，用pH 6.0缓冲的脱落酸预处理通常会使伸长反应进一步降低。在任何这些实验中，脱落酸都没有完全阻止pH效应，并且pH反应的短暂潜伏期不受脱落酸处理的影响。在pH 4.5时，ABA的抑制作用最大，低pH诱导的伸长也受到KCN和HgCl₂的抑制。这些结果表明，该系统中pH-（4.5）诱导的伸长可能依赖于某些代谢过程，并且脱落酸诱导的这种伸长抑制可能涉及与这些过程的相互作用。
