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Abstract

Using demographic toxicology, an experiment was carried out to evaluate effects of pyriproxyfen, and buprofezin (Insect growth regulators) as well as fenpropathrin (a pyrethroid) on population growth parameters in greenhouse whitefly T. vaporariorum. To determine these parameters, leaf cages were put on bean leaves which had already been immersed in sublethal concentrations of the above mentioned insecticides. A virgin female with two males were released into the cage, and the progenies were reared, at 26±1?C, 60±5% RH and a photoperiod of 16: 8 (L: D) until becoming adults. Thereafter, various parameters such as intrinsic rate of increase (rm), gross and net reproductive rate (GRR and R0) as well as doubling time (DT) were estimated. The estimated rm values in control, pyriproxyfen, buprofezin and fenpropathrin were 0.122, 0.067, 0.0759 and 0.0759 respectively, and in comparison with control, there were 29, 38 and 38% reductions observed respectively. R0 was 24.4, 9.6, 7.3 and 6.9, and with DT of 5.68, 7.99, 9.13 and 9.12 days in the treatments of control, pyriproxyfen, buprofezin and fenpropathrin, respectively. Moreover, other parameters indicated reliable reductions in the relevent treatments. Results indicated that pyriproxyfen and buprofezin didn’t have any detrimental effects on adult longevity, while they induced infertility for at least 8 days after adult emergence. In contrast, fenpropathrin caused heigh mortality as well as considerable reduction in longevity. Therefore, it could be concluded that pyriproxyfen and buprofezin might be the proper choices for pest control in an integrated pest management program.

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