Sublethal effects of some synthetic and botanical insecticides on Bemisia tabaci (Hemiptera: Aleyrodidae)

Abstract

In addition to direct mortality caused by insecticides, some biological traits of insects may also be affected by sublethal insecticide doses. In this study, we used the age-stage, two-sex life table method to evaluate the sublethal effects of the four synthetic insecticides: abamectin, imidacloprid, diazinon, and pymetrozin as well as the botanical insecticide taken from Calotropis procera (Asclepiadaceae) extract, on eggs of the cotton whitefly, Bemisia tabaci (Hem.: Aleyrodidae). The lowest and highest survival rates and oviposition periods were observed in whiteflies treated by diazinon and imidacloprid, respectively. We found significant differences in the net reproductive rate (R0), the intrinsic rate of increase (r), the finite rate of increase (?), and the gross reproductive rate (GRR) among different insecticides. Altogether, our results showed that pymetrozin and C. procera induced the most sublethal effects, thus they may be suitable candidates for use in integrated pest management programs of B. tabaci.

Effects of imidacloprid-induced hormesis on the development and reproduction of the rose-grain aphid Metopolophium dirhodum (Hemiptera: Aphididae)

“…Additionally, the population prediction results show that an exposure to sub-lethal concentrations of imidacloprid induced M. dirhodum population growth. Similar effects on population growth were observed in an earlier study on sweetpotato whitefly B. tabaci, which proved that imidacloprid Frontiers in Physiology frontiersin.org increases the gross reproduction rate, but does not significantly affect the mean generation time (Esmaeily et al, 2014). Another study involving field experiments in Australian revealed that the egg production and population development of the Australian predatory mite Amblyseius victoriensis (Womersley) significantly increase in response to systemic spray treatments of imidacloprid (James, 1997).…”

Impact of low lethal concentrations of buprofezin on biological traits and expression profile of chitin synthase 1 gene (CHS1) in melon aphid, Aphis gossypii

“…Previously, similar effects were documented on the offspring of white-backed planthopper, Sogatella furcifera 29 , cotton aphid, A . gossypii 63 , and brown planthopper, Laodelphax striatellus 64 when subjected to the sublethal concentrations of buprofezin, sulfoxaflor, and thiamethoxam.…”

Sublethal effects of buprofezin on development and reproduction in the white-backed planthopper, Sogatella furcifera (Hemiptera: Delphacidae)

“…These effects are related to reductions in the intrinsic rate of increase ( ri ), finite rate of increase (λ), net reproductive rate ( R 0 ), gross reproduction rate ( GRR ) and survival rate. Such effects on offspring growth have also been reported in the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) and the small brown planthopper, Laodelphax striatellus (Homoptera: Delphacidae) through treatment with sublethal concentrations of sulfoxaflor and thiamethoxam 39 , 40 . Other insecticides, such as imidacloprid, chlorantraniliprole and triazophos have also lead to significant effects on the life cycle of the white-backed planthopper 23 , 26 , 41 .…”

“…Other insecticides, such as imidacloprid, chlorantraniliprole and triazophos have also lead to significant effects on the life cycle of the white-backed planthopper 23 , 26 , 41 . Although imidacloprid significantly affects the GRR in various cases, the generation time ( T ) was not affected in B. tabaci (Hemiptera: Aleyrodidae) 40 . Lashkari et al .…”