اثرات زیرکشندگی حشره کش‌های آزادیراکتین و پالیزین بر ویژگی های زیستی، فراسنجه‌های جدول زندگی و پیش بینی روند جمعیتی Trialeurodes vaporariorum (Hemiptera: Aleyrodidae)

The greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae), is known as an economically important and polyphagous pest of different crops. Usage of low-risk and ecological friendly insecticides could be consider as a complementary method in integrated pest management of aforementioned pest. For this purpose, in this study, the sub-lethal concentration (LC25) of two insecticides, Azadirachtin and Palizin, on the biological properties and life table parameters of T. vaporarium were studied at controlled condition. The leaves of tomato were dipped into the related concentrations of insecticides, then the same-aged (24h) adults of, T. vaporariorum were released on the treated leaves. The sub-lethal (LC25) obtained concentration were used 5.3 and 5.6 p.p.m for Azadirachtin and Palizin, respectively. The biological and life table studies were done using at least 80 the same age of eggs for each treatments. The life history data of the greenhouse whitefly cohorts exposed to sublethal concentration of the aforementioned insecticides were analyzed using the computer program TWOSEX–MSChart based on the age-stage, two-sex life table theory. The results of this study were showed that the used insecticides affected the developmental time, survival rate, adult longevity, and fecundity of the F1 generation. The developmental time on control, Azadirachtin and Palizin treatments was obtained (21.72±0.21 days), (23.57±0.25 days) and (23.38±0.36 days), respectively. The fecundity rate of greenhouse whitefly was varied from 35.96± 2.53 (egg/female) on control to 8.64 ± 2.67 (egg/female) on Azadirachtin. Also, the sublethal concentration of both insecticides resulted in decreasing of the net reproductive rate (R0), intrinsic rate of increase (r), and the finite rate of population growth (λ). The highest and lowest net reproductive rate was obtained on control (9.58 ± 1.80 eggs/female) and Azadirachtin and Palizin (1.03 ± 0.042 and 1.67 ± 0.041 eggs/female), respectively. The highest values for the intrinsic rate of increase and finite rate of increase were obtained on control (r: 0.0865 ± 0.0074 day-1, λ: 1.090 ± 0.0080 day-1), respectively. The results also demonstrated that population growth of the greenhouse whitefly in different treatments was exactly in consistent with the estimated population growth parameters. For example, aphids treated with Palizin, had slower growth rate and, thereby prolonged mean generation time (T).Therefore, the findings of this research showed that, due to the sublethal effects of both insecticides on the biological and life table parameters of the greenhouse whitefly, they could be used in the management of aforementioned pest.