Sublethal Exposure to Deltamethrin Stimulates Reproduction and Alters Symbiotic Bacteria in Aphis gossypii

Abstract

In aphids, hormesis and symbiotic bacteria are the drivers for the development of pesticide resistance. However, the related mechanism remains unclear. Here, we evaluated the sublethal and transgenerational effects of the extensively used pyrethroid pesticide deltamethrin (DMT) on the population dynamics in Aphis gossypii and tested its influence on symbiotic bacterial communities. The leaf-dip bioassay revealed that DMT was highly toxic to A. gossypii, and at a low lethal concentration of DMT, the intrinsic (r) and finite rates of increase (λ) of the initially exposed aphids (G0) significantly decreased. Intriguingly, the r, λ, and net reproductive rate (R 0) of G1 and G2 significantly increased, but the r and λ decreased in G3. The adult and total preoviposition period increased in G3 but decreased in G4. Additionally, the diversity of the bacterial community decreased, while the abundance values of Buchnera, Pseudomonadaceae, and Burkholderiaceae increased after 24 h of exposure to LC30 DMT in G0 aphids, and the latter two decreased in G1 but increased in G2. In summary, sublethal DMT has intergenerational hormesis effect on cotton aphids in G1–G2 and remarkably altered their symbiotic bacterial community and abundance. These results broaden our understanding of the relationship of hormesis and symbiotic bacteria in aphids under insecticide exposure.

Sublethal and transgenerational effects of pyridaben exposure on the fitness and gene expression of Panonychus citri

“…Thus, pyridaben exposure led to reproduction stimulation on the F 1 generation of P. citri at LC 30 concentrations. Similar effects have been observed for several pesticides like sulfoxaflor, deltamethrin, and acetamiprid on A. gossypii 48,49,61 . Age‐specific fecundity ( m x ), age‐specific net maternity ( l x m x ), and age‐specific reproductive value ( v xj ) parameters can provide important details regarding the reproductive capacity of pest populations.…”

“…Similar effects have been observed for several pesticides like sulfoxaflor, deltamethrin, and acetamiprid on A. gossypii. 48,49,61 Age-specific fecundity (m x ), age-specific net maternity (l x m x ), and age-specific reproductive value (v xj ) parameters can provide important details regarding the reproductive capacity of pest populations. The m x , l x m x and v xj parameters of F 1 generation P. citri individuals exposed to LC 30 levels of pyridaben were higher than those of the controls for the pyridaben-resistant strain.…”

Contribution of insect gut microbiota and their associated enzymes in insect physiology and biodegradation of pesticides

“…However, it offers an appropriate environment that stimulates the proliferation and diversification of insect gut microbiomes ( Bruno et al, 2019 ). Many studies have reported that insect gut microbiota plays a significant role in developing symbiotic insect interactions facilitated by secondary metabolites ( Shang et al, 2021a ). Besides this, they also play an essential role in the detoxification of pesticides, providing a natural defense system, nutrient availability, development of resistance against toxins and pathogens, breakdown of food, and suitable for proper growth of insects ( Jang and Kikuchi, 2020 ; Jing et al, 2020 ; Mogren and Shikano, 2021 ; Tilottama et al, 2021 ).…”

Sublethal phosphine fumigation induces transgenerational hormesis in a factitious host, Corcyra cephalonica

“…104 As in the present study, increased abundance of a few phyla or species of symbionts in a particular sublethal treatment group has been previously reported in other pest insect, A. gossypii. 105 Furthermore, earlier research has demonstrated that xenobiotic stress can cause changes in abundance of symbionts in soybean aphids. 106…”