Assessment of sublethal and transgenerational effects of spirotetramat, on population growth of cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae)

Abstract

The cabbage aphid (Brevicoryne brassicae L.) is a devastating pest of cruciferous crops causing economic damage worldwide and notably owing to its increasing resistance to commonly used pesticides. Such resistance prompts the development of integrated pest management (IPM) programs that include novel pesticides being effective against the aphids. Spirotetramat is a novel insecticide used against sap-sucking insect pests, particularly aphids. This study evaluated the toxicity of spirotetramat to adult apterous B. brassicae after 72 h using the leaf dipping method. According to the toxicity bioassay results, the LC50 value of spirotetramat to B. brassicae was 1.304 mgL−1. However, the sublethal concentrations (LC5 and LC15) and transgenerational effects of this novel insecticide on population growth parameters were estimated using the age-stage, two-sex life table theory method. The sublethal concentrations (LC5; 0.125 mgL−1 and LC15; 0.298 mgL−1) of spirotetramat reduced the adult longevity and fecundity of the parent generation (F0). These concentrations prolonged the preadult developmental duration while decreasing preadult survival, adult longevity and reproduction of the F1 generation. The adult pre-reproductive period was also extended by spirotetramat treatment groups. Subsequently, the population growth parameters such as the intrinsic rate of increase r, finite rate of increase λ and net reproductive rate R0 of the F1 generation were decreased in spirotetramat treatment groups whereas, the mean generation time T of the F1 generation was not affected when compared to the control. These results indicated the negative effect of sublethal concentrations of spirotetramat on the performance of B. brassicae by reducing its nymphal survival, extending the duration of some immature stages and suppressing the population growth of B. brassicae. Overall, we demonstrated that spirotetramat is a pesticide showing both sublethal activities, and transgenerational effects on cabbage aphid; it may be useful for implementation in IPM programs against this aphid pest.

Sublethal and Transgenerational Effects of Nitenpyram on <em>Acyrthosiphon gossypii</em> and Its Impacts on Symbiotic Bacteria

“…On the contrary, under the stress of sublethal concentration of nitenpyram, the mean generation time (T) of A. gossypii was significantly higher than that in the control group. This might be attributed to the energy shortage induced by insects' adaptation to the pesticide stress under the exposure to pesticides [48]. Furthermore, the reduced fecundity and lifespan indicate hormesis deficiency, which is an important manifestation of the sublethal effects of pesticides [46].…”

Sublethal Effects of Spirotetramat, Cyantraniliprole, and Pymetrozine on Aphis gossypii (Hemiptera: Aphididae)

“…Treatment of the cabbage aphids Brevicoryne brassicae and Frankliniella occidentalis with spirotetramat at sublethal concentrations prolonged the preadult development duration, while the preadult survival, adult longevity, and reproduction of the F 1 generation decreased [12,13]. At sublethal concentrations, chlorantraniliprole decreased the fecundity of Spodoptera frugiperda, S. cosmioides, and Helicoverpa armigera, which required a prolonged developmental period, resulting in significantly lower population growth parameters than those in the control group [14][15][16].…”

Sublethal insecticide exposure of larvae affects the blood-feeding behaviour of adult mosquitoes

“…Insecticides, for example, impair the olfactory systems of mosquitoes 19,20 , thus impeding their responses to attractants involved in host-seeking and oviposition 11,[21][22][23] . Some effects of an exposure to a low dose of insecticide can carry on to the next generation: the offspring of mothers that had been exposed to a low dose of a pyrethroid were bigger as larvae and pupae than those of unexposed individuals 24 , while a low dose of spirotetramat decreased body size and longevity in the offspring of cabbage aphids 25 .…”