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bioRxiv · 10.1101/563031

A meta-analysis on the benefits and costs of hosting secondary endosymbionts in sap-sucking insects

Zytynska, S. E.·Thighiouart, K.·Frago, E.
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Abstract

Herbivorous insects host various bacteria that help them to feed, grow, and survive. Sap-sucking insects, in particular, feed on a nutrient-poor resource and have evolved obligate symbioses with nutritional bacteria for survival. Additionally, sap-sucking insects have formed facultative associations with bacterial symbionts that are not essential for growth and survival but assumed to confer some benefits, such as resistance to natural enemies. Several recent reviews have highlighted the importance of these symbionts in understanding their hosts biology, but currently there is a lack of a quantitative and systematic analysis of the published evidences exploring whether the different endosymbionts are actually beneficial or not. In this meta-analysis we explored the potential costs and benefits associated with hosting facultative endosymbionts in sap-sucking insects. Our first result is that most of the empirical experimental data information is limited to a few species of aphid and one species of whiteflies. Through the meta-analysis we showed that hosting symbionts generally leads to costs through increased development time, reduced longevity, and reduced fecundity, and benefits via increased resistance to parasitic wasps in sap-sucking insects. However, the impact of these costs and benefits was strongly insect and symbiont species dependent. Many of the insects studied are agricultural pests, and understanding the impact of bacterial symbionts on their hosts across different environments can benefit sustainable management of greenhouses and agricultural land.

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Zytynska, S. E., Thighiouart, K., Frago, E.. 2019-02-28. A meta-analysis on the benefits and costs of hosting secondary endosymbionts in sap-sucking insects. https://doi.org/10.1101/563031

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