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

Thiacloprid + Deltamethrin on the Life-Table Parameters of the Cotton Aphid, Aphis gossypii (Hemiptera: Aphididae), and the Parasitoid, Aphidius flaviventris (Hymenoptera: Aphelinidae)

Journal of Economic Entomology ◽

10.1093/jee/toaa214 ◽

2020 ◽

Vol 113 (6) ◽

pp. 2723-2731

Author(s):

Marzieh Majidpour ◽

Nariman Maroofpour ◽

Mojtaba Ghane-Jahromi ◽

Raul Narciso C Guedes

Keyword(s):

Pest Management ◽

Life Table ◽

Sublethal Effects ◽

Aphis Gossypii ◽

Parasitoid Wasp ◽

Cotton Aphid ◽

Life Table Parameters ◽

Parasitism Rate ◽

Sublethal Exposure ◽

Negative Impacts

Abstract A combination of pesticides and biological control agents is frequently necessary to achieve successful pest management requiring the assessment of their compatibility for the intended purpose. Aphidius flaviventris Kurdjumov is one of the parasitoids of the cotton aphid Aphis gossypii Glover, whose susceptibility to pesticides was not yet investigated. Accordingly, we investigated the lethal and sublethal effects of the commonly utilized insecticide mixture thiacloprid + deltamethrin on the cotton aphid and its parasitoid wasp Aphidius flaviventris. The estimated LC50 for the aphid was 14.1 mg ai/l; the effects of sublethal exposure at LC10 (2.80 mg ai/l) and LC30 (7.28 mg ai/l) on the aphid life-table parameters led to significantly increase on the development time of third- and fourth-instar nymphs and preadult. Sublethal exposure to the insecticide mixture compromised aphid longevity, fecundity, and life-table parameters (r, R0, and T). Moreover, population growth and parasitism rate of the parasitoid were significantly compromised at both concentrations of the insecticide mixture under sublethal exposure. These results not only indicate the efficacy of thiacloprid + deltamethrin against the cotton aphid, but also raise concerns regarding its negative impacts on the parasitoid Aphidius flaviventris and caution against its use in pest management programs.

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Microbiome diversity of cotton aphids (Aphis gossypii) is associated with host alternation

Scientific Reports ◽

10.1038/s41598-021-83675-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Yan-jie Ma ◽

Hao-peng He ◽

Hai-meng Zhao ◽

Yi-dan Xian ◽

Hui Guo ◽

...

Keyword(s):

Bacterial Communities ◽

Host Plants ◽

Aphis Gossypii ◽

Principal Component ◽

Illumina Miseq ◽

Aphid Species ◽

Symbiotic Bacteria ◽

Host Alternation ◽

Specific Host ◽

Rdna Sequencing

AbstractAphids are infected by a series of bacteria that can help them survive on specific host plants. However, the associations between aphids and these bacteria are not clear, and the bacterial communities in many aphid species are poorly characterized. Here, we investigated the bacterial communities of cotton aphids (Aphis gossypii) on 2 representative winter host plants and transferred to 3 summer host plants by 16S rDNA sequencing using the Illumina MiSeq platform. Our results revealed that the bacterial communities varied among cotton aphids on hibiscus, cotton aphids on pomegranate, cotton aphids on cotton transferred from hibiscus, cotton aphids on muskmelon transferred from hibiscus, cotton aphids on cucumber transferred from hibiscus,. The diversity and richness of the bacterial communities were significantly higher in aphids on muskmelon and aphids on cucumber than in the other treatments. There were two main factors influencing the distribution of internal bacterial OTUs revealed by principal component analysis, including the differences among Punicaceae, Malvaceae and Cucurbitaceae. There were 28 bacterial communities with significant differences between two arbitrary treatments, which could be grouped into 6 main clusters depending on relative abundance. Moreover, our results indicated that in addition to the obligate endosymbiont Buchnera, with a dominant position (> 52%), A. gossypii also harbored 3 facultative endosymbiotic bacteria (Serratia, Arsenophonus, and Wolbachia) and 3 possibly symbiotic bacteria (Acinetobacter, Pantoea, and Flavobacterium). There were several correspondences between the symbiotic bacteria in cotton aphids and the specific host plants of the aphids. This study provides a better understanding of the interactions among symbiotic bacteria, aphids and host plants, suggesting that the selection pressure on aphid bacterial communities is likely to be exerted by the species of host plants.

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