A method for rapid testing of the photosynthesis-inhibiting activity of herbicides by leaf disk infiltration

Krzysztof Bielecki, Halina Doroszewicz, Edward Grzyś, Zdzisława Szuwalska


A method for rapid detection of photosynthesis inhibitors in low concentration (0.25-1.25 ppm) was developed. The experiments were performed on disks cut from young bean leaves. The disks were infiltrated with solutions of the tested compounds and placed at the bottom of a crystallizer containing an acidic sodium carbonate solution and then illuminated. The toxicity of the tested substance was measured as the number of disks corning to the surface. It was found that linuron, monolinuron, metoksuron, atrazine and prometrine inhibited floating of the disks, whereas 2,4,5-T, MCPA and chlorpropham gave no effect. This confirms the specificity of the test which is appropriate for determining the phytotoxicity of typical photosynthesis inhibitors.

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