Quantitative relationship of application rate and pesticide residues in greenhouse tomatoes.

The association between application rate of a pesticide and its residue in ripe tomatoes was studied. The average residue level (R) of any pesticide in ripe tomatoes remained in quantitative relation to its dose (D), expressed by the following regression equation: R = 0.24 D (mg/kg), where the numerical factor, 0.24, represents the average residue in mg/kg after application of 1 kg active ingredient per hectare with relative standard deviation of 23%. Quantitative association between these 2 factors enables evaluation of greenhouse tomato growers with respect to their observation of Good Agricultural Practice rules and the Plant Protection Act, obligatory in Poland since 1996, and thus may be a reliable basis for the registration of new agrochemicals.