Interaction of Abscisic Acid and 6-Benzylaminopurine on the Metabolism of Lemna minor L.

The effects of abscisic acid (ABA) and 6-benzylaminopurine (BAP)on growth and the contents of chlorophyll, protein and nucleicacid of fronds of Lemna minor were studied. The frond multiplicationrate was reduced by 10^–6 M ABA but increased by 10^–6M BAP. When both substances were added simultaneously to theculture medium, the growth inhibition expected from ABA wasreduced considerably by the presence of BAP. The chlorophyll content per frond was increased by ABA whilethat per flask was reduced by ABA and increased by BAP. WhenABA and BAP were added together, the ABA effect was reducedby BAP. A similar response was detected in the nucleic acidcontent; ABA caused a decrease during the early phase of treatmentwhile BAP increased it. In this case, treatment with ABA$BAPalso showed that BAP could reduce the ABA effect. However, thiseffect was not observed on the protein content. ² Present address: Departamento de Agricultura, Facultad deVeterinaria, Universidad Aut?noma de Barcelona, Bellaterra,Barcelona, Spain. (Received June 6, 1984; Accepted September 10, 1985)