maneb and dichlofluanid

Laboratory results of the French ANPP/CEB guideline No. 167 and IOBC/WPRS Ring Testing Group methods for testing the side effects of pesticides on the predatory mite Typhlodromus pyri Scheuten were compared with respect to their suitability to evaluate the toxicity of three pesticides.. Results obtained with the ANPP/CEB guideline allow the demonstration of significant differences between two slightly toxic products, a dichlofluanid 500 g kg(-1) kWP (Euparen) 50WP) and a quinoxyfen 250 g L(-1) SCC (Legend), and a highly toxic cymoxanil 60/mancozeb 200/folpet 275 g kg(-1) WP [Remiltine F Pepite) (RFP)], on the basis of bioassays conducted in the laboratory. In contrast, results obtained with the IOBC/WPRS method classified all three as harmful.. The evaluation of the toxicity of RFP revealed that the concentration, the quantity of the wet deposit and the food source used in the IOBC/WPRS method maximise the toxicity, in comparison with those used in the ANPP/CEB protocol. Valid criteria in controls were all respected in the ANPP/CEB tests but not in the IOBC/WPRS samples. This result revealed difficulties related to the use of the IOBC/WPRS method in laboratories.

Topics: Acari; Acetamides; Aniline Compounds; Animals; Biological Assay; Fertility; Insecticides; Larva; Maneb; Nymph; Ovum; Phthalimides; Quinolines; Reproducibility of Results; Sensitivity and Specificity; Zineb

Two types of reactions were observed on the alteration of Drosophila vitellogenesis by the four fungicides used in this study. Dithane M45 resulted in stimulation associated with egg retention. However, the other three fungicides (Benlate, Bouillie bordelaise and Euparène) resulted in inhibition to a varying degree. Although the inhibition was comparatively limited due to Benlate it induced an egg retention. The inhibition was very high due to Bouillie bordelaise and Euparène. With Bouillie bordelaise an egg retention occured together with the reduction of vitellogenesis and caused an increase in the rate of the follicle resorption. The latter depended on the duration of treatment. With Euparène, no egg retention was observed and the toxicity was only noticed on vitellogenesis.

Topics: Aniline Compounds; Animals; Benomyl; Copper Sulfate; Drosophila melanogaster; Female; Fungicides, Industrial; Maneb; Ovary; Vitellogenesis; Zineb

Four day old Drosophila pairs were maintained on nutritive media surface treated with fungicide doses according to the standard level recommended by the manufacturers. The flies were treated for 1 to 6 weeks and the eggs laid in 3 hours were counted each week during and after treatment. The capacity of treated flies egg laying was determined on treated media and then on untreated one. For the benomyl preparation (Benlate) and the mancozebe preparation (Dithane M45), there was an overall reduction of the egg mass on treated media but not on untreated media. There appears to be an essential repulsive effect which perturbs egg laying and causes a retention of eggs. However, after 3 to 4 weeks the quantity of egg mass also diminished on untreated media. Once the treatment was terminated the capacity to lay eggs partially returned. The copper sulfate preparation (Bouillie bordelaise) also exhibited a repulsive effect as exhibited by a retention of a certain number of eggs, but there was a more direct and fast effect on fecundity. Effect was more brutal with the dichlofluanide preparation (Euparène), and rapidly irreversible: the egg masses were very reduced after only one week of treatment on both treated and untreated media, and after termination of treatment there was an incomplete and temporary recuperation of the capacity to lay eggs. The results presented here are in agreement with those obtained previously concerning longevity. At the doses recommended for agricultural treatments, Benlate and Dithane M45 showed low toxicity for Drosophila adults in comparison with Bouillie bordelaise and Euparène which revealed a high toxicity in agreement with the fecundity and longevity data.

Topics: Aniline Compounds; Animals; Benomyl; Copper; Copper Sulfate; Drosophila melanogaster; Female; Fertility; Fungicides, Industrial; Male; Maneb; Oviposition; Zineb