Effect of diflubenzuron and its major degradation products on the growth of Euglena gracilis Z. and incorporation of glycine-U-14C in protein.

Diflubenzuron (I) and its major degradation products 4-chlorophenyl urea (II), 2,6-difluorobenzoic acid (III) and 4-chloroaniline (IV) were tested for their activity on Euglena gracilis Z. The inhibition on the growth and on the incorporation of glycine-U-14C in the protein of Euglena was measured in the presence of I-IV ranging 10 to 200 ppm. 4-chloroaniline caused a considerable inhibition at every tested level whereas I-III slightly affected only the incorporation. Therefore, it must be inferred that diflubenzuron shows no effect on growth and protein biosynthesis for this nontarget organism.