Department of Botany, University of Natal, South Africa.
Planta. 1969 Jun;85(2):157-9. doi: 10.1007/BF00388545.
The effect of different concentrations of abscisic acid on the growth of Spirodela oligorrhiza has been studied. Abscisic acid effectively permanently arrests growth at concentrations down to 10(-1) mg/l (one part per 10 million). Normal growth tends to be resumed at concentrations of 10(-2) and 10(-3) mg/l between 9 and 12 days after treatment. A concentration of 10(-8) mg/l, however, results in a significant increase in dry weight at both 9 and 12 days after introduction to the culture medium. It is suggested that the resumption of growth 12 days after treatment at those concentrations which inhibit growth up to 9 days, is due to a possible progressive inactivation of abscisic acid resulting in a lowering of its concentration to a level that is promotive. Sterile plants must be used since abscisic acid has shown no effect whatsoever in controlling growth of Saprolegnia, a water-mould of the Phycomycetes to which Spirodela apparently is the host.
研究了不同浓度的脱落酸对紫萍生长的影响。脱落酸在低至 10(-1) 毫克/升（每 1000 万份中有 1 份）的浓度下能有效永久停止生长。在处理后 9 至 12 天，浓度为 10(-2) 和 10(-3) 毫克/升时，正常生长往往会恢复。然而，在引入培养基 9 和 12 天后，10(-8) 毫克/升的浓度会导致干重显著增加。这表明，在抑制生长长达 9 天的浓度下，12 天后生长的恢复可能是由于脱落酸的逐渐失活，导致其浓度降低到促进生长的水平。由于脱落酸对水霉，即显然是紫萍宿主的藻菌纲的水霉，在控制生长方面没有任何作用，因此必须使用无菌植物。
